Feel free to ask Myles

[myles_rose]

Originally posted by dave251:

Myles- What would be the audible difference between AC heated filaments and DC heated filaments? We're getting ready to start on the second amp and this question came up....

 

Thanks,

dave251,

 

There is not a difference in program material sonic quality, but there can be a difference in background noise sonic quality.

 

With DC heaters, the amp may have less 60 cycle hum on the preamp tube which depending on the rest of the circuit may make a difference.

 

DC heaters are a bit more expensive, but are worth it in the long run, especially in an amp that you may want to be as quiet as possible. It is also a sign of a good design when somebody turns on an amp and it is not noisy.

 

Regards,

[myles_rose]

Originally posted by overcomer:

oh yeah, that is a tremendous help, i had thought ( while i was waiting for your reply) about getting a pair of the new groove tube 6L6 ge's. and the info you have given is really quite extensive. too bad i live so far away, i would definitely give you some business. now all i have to do is advise my sometime tech, who is very capable, of your insight and go from there... thanks again.

overcomer,

 

I'd love your business, but I do not sell tubes. When I work on amps, I have clients bring their own tubes, and then I test and classify them. I do keep preamp tubes for my clients, but these are not for sale, they are in reserve for their use.

 

As far as the GT 6L6GE's, these would be magic in your amp. There was a great article that was done by Harmony Central on this tube on 4/29, a few days ago. I copied this article and posted it in the Groove Tubes area of my website, so there is now even more information on this tube. Its at www.guitaramplifierblueprinting.com/groovetubes.html

 

In any case, good luck, and you are welcome.

 

Regards,

[myles_rose]

Originally posted by mikey:

Thanks Miles for all the great info. I am still working with my Fender Deville I picked up last week. Would I be disappointed by using a 12AT7 in the rectifier spot? Also what's better Svets 6L6 or Groove Tubes?

mikey,

 

If you mean using a 12AT7 in the phase inverter position, it will give you more clean headroom in teh output section. Just give it a try, its a matter of taste. Turn your master all the way up and then set the volume to the point, when your guitar is all the way up, that you just get the onset of output tube distortion.

 

Then, with the same settings, try the same thing with the 12AT7 in place of a 12AX7, and you will see you have a cleaner sound. This assumes that the 12AX7 you have in there now is about where one is supposed to be, spec wise, which is something of a crap shoot, and the 12AT7 is also close to mid spec. The only way to know for sure is to measure your tubes, but for the cost of a 12AT7, its a cheap experiment where you might love the results.

 

As far as Groove Tubes vs. the Svets, the Groove Tubes 6L6R2 is a Svetlana tube. The difference on this tube is how it is matched. This is why GT tubes last about 20% longer than most tubes from the "same" maker, and turn out to generate a more symmetrical output waveform. In the case of some GT tubes, GT gets involved with the tube factory and makes some subtle changes specifically for them. If you look at a JJ E34L and an GT E34Ls, which are supposed to be the "same tube", you will see a different plate structure on the outside of the assembly.

 

The GT 6L6R2 is a great tube, and the Svetlana 6L6 is a great tube, and if properly matched, they are both terrific. I prefer them to the JJ's, but then I am an old coot, and more into blues than speed metal. In the case of EL-34 amps though, I prefer the E34L JJ tube or GT E34Ls over the Svetlana EL-34. Then again, its personal preference. Actually, if I had a choice and could afford them, for EL-34 amps I'd always pick a KT-77 GEC as second choice and a good USA 6CA7 as first choice if I could afford them.

 

Regards

[overcomer]

well, what i meant to day and didnt was that the term conscientious used to be known only in the term "conscientious objecter", in the days of the draft, which dates me, my number was high in 1970. i am glad you are putting this info out, it is a great resource. it seems the tube world, and also the UPS, USPS, and fedex "gods" of this realm are taking their due of our dollar, but i dont fault the tube world really, with modeling amps and things coming in, tubes are really taking a beating. my amp tech, the one i will take my super to, does not use tubes that are over 40 bucks a pair, he is a super "rebuilder" from tulsa named rick potter, and quite good and really, i am glad that new tubes are available. it would be a shame to have amps with no tube tone. one fellow came into the music store i visit and was talking about how he was looking for a solid state amp because his peavy classic 30 fell off the back of the seat of his car and it messed up a tube. his idea of amps is, if it has the least bit of problem it is no good. i have a 100 watt harry joyce head with 4 el34s and 4 ei 12ax7s, but i cant find a rectifier tube on it, it must have a solid state in there. i am through amp searching, but thought it would be a good idea to find a way to lower the head room on this super, use it in conjunction with the joyce, which is mammoth clean and also overdriven. it is a beast like no other i have ever played, harry joyce is dead now, but i am glad i got one of them. it is great for huge stage clean, but then again, so is evans, hah, but tubes have the warmth. well, i have rambled, and again, this is a great resource...i meant to say that it is very cool that you are conscientious, as many are not, it is a gift. sorry for the multiple posts...

[Gearasameanstoamusicalend]

Originally posted by myles111:

[QB] . . . if you have a question or have a comment, just post a comment here and when I see the email notification I will answer back here as quickly as I am able . . . /QB]

Dear Myles, Have enjoyed reading your posts and have learned from them. Thank you. My questions regard an older solid state amp. I purchased a Polytone Mini-Brute amplifier. However, this is an older model, head only, no speakers. I think that it is a PA application. However, it has instrument inputs only, and no XLR. It has three channels and one line out. I bought this at an auction very cheap, sound unheard. It is one of the black velour models, pre vinyl tolex. My questions follow: Is the line out an instrument line, or a speaker line, meaning what kind of cable would I use to connect to a speaker? What ohm rating would be the proper match in a speaker cabinet? Does it matter whether it is 4 or 8 ohms? Thanks for having this post. Best regards!

[sgguitarzz]

Hey Miles. I am hoping you can help me. I was hoping you can give me some tube advice for my Boogie Mark IIB. It sounds okay but we are all always looking for better. It has the 60/100 option which I always use on 60 which is still too loud anyway. I use it with two Reverend Alltone 1250's (one internal and one external). I really like these speakers. Great versatile and warm sound. It also has reverb and equalizer. I was using 4 JJ 6L6GC's for the power tubes but switched out the outer two and replaced them with THD Yellowjackets. My preamp tube setup is as follows:

 

V1 - Telefunken ECC83

V2 - Mullard CV4004

V3 - Brimar CV4004

V4 - Telefunken ECC83

V5 - RCA 5751

 

Any comments or suggestions would be appreciated. I play classic rock so I need to cover a lot of sounds and I cannot go too far in any one direction. Also, my main guitar is a 69 Gibson SG backed up with a newly aquired PRS Santana SE which I like. Finally, I use a pedalboard with various effects such as wah (Teese RMC1), overdrive/distortion (Visual Sound J&H), chorus/echo (Visual SOund H20), EQ (Dano Fish & Chips), Flanger (Ibanez FL9), Phaser (Akai Intelliphase) and booster (MXR micro amp).

Sorry for the long post. Thanks.

 

Dennis

[myles_rose]

Originally posted by overcomer:

well, what i meant to day and didnt was that the term conscientious used to be known only in the term "conscientious objecter", in the days of the draft, which dates me, my number was high in 1970. i am glad you are putting this info out, it is a great resource. it seems the tube world, and also the UPS, USPS, and fedex "gods" of this realm are taking their due of our dollar, but i dont fault the tube world really, with modeling amps and things coming in, tubes are really taking a beating. my amp tech, the one i will take my super to, does not use tubes that are over 40 bucks a pair, he is a super "rebuilder" from tulsa named rick potter, and quite good and really, i am glad that new tubes are available. it would be a shame to have amps with no tube tone. one fellow came into the music store i visit and was talking about how he was looking for a solid state amp because his peavy classic 30 fell off the back of the seat of his car and it messed up a tube. his idea of amps is, if it has the least bit of problem it is no good. i have a 100 watt harry joyce head with 4 el34s and 4 ei 12ax7s, but i cant find a rectifier tube on it, it must have a solid state in there. i am through amp searching, but thought it would be a good idea to find a way to lower the head room on this super, use it in conjunction with the joyce, which is mammoth clean and also overdriven. it is a beast like no other i have ever played, harry joyce is dead now, but i am glad i got one of them. it is great for huge stage clean, but then again, so is evans, hah, but tubes have the warmth. well, i have rambled, and again, this is a great resource...i meant to say that it is very cool that you are conscientious, as many are not, it is a gift. sorry for the multiple posts...

Your "number" dates you? I have you beat there. When I got out of high school, they did not even have the lottery yet! We had limited options ... enlist, get drafted, go to Canada, go to prison after burning your draft card, or hold down 16 1/2 units in college. The last choice was not an option for a screw up like me, so I enlisted.

 

Modeling amps have their place in the studio or for composition, but I have yet personally heard one that I feel can stand on its own without any effects and have the dynamics of a tube amp. Perhaps someday.

 

I think having a price of less than $40 for a set of tubes is somewhat limiting, but if your tech can make your amp sound good to you with tubes like that, then that is super. I wonder how it would sound with some closely matched great ones though? It would be fun to do something of a blind test where your amp had its output tubes pulled and something else tried, to see what you felt about the difference. I will say, I have heard some great Fender amps with the least expensive Sovtek's in there, but that were set up properly, and they sounded a LOT better than the same amp model with expensive NOS tubes that were not matched and had the bias improperly set for the amp. A good tech can make a good amp sound great.

 

Your Joyce head has a solid state rectifier, and solid state rectifiers are pretty much the only choice in a 100 watt amp, as a GZ34 is doing about its best with a 50 watt amp. These amps are monsters and a nice tight regulation circuit is just what these amps need. When was the last time you saw a tube rectifier after 1965 in a 100 watt head like a Marshall or Hiwatt? Never, with the exception of the Mesa Rectifiers, and they use one for each 50 watt section.

 

As far as the multiple posts .... nobody is counting (and of they are, maybe they need something better to do).

 

Regards,

[freddynl]

Hello Miles,

I could not find the answer with the search so I guess the question was not asked yet.

It looks like I will start with some gigging after 20 years of absence..

Now I undusted an old fender concert amp (1983 black faced- 60 watts rms) I still had in a corner.

It probably needs some new tubes.

So my question is what tubes would you recommand for this amp, to get as clean as possible!

(I will use it for jazz so I don't want dirty output )

 

Thanks for advice,

 

Fred

[myles_rose]

Originally posted by Gearasameanstoamusicalend:

Originally posted by myles111:

[QB] . . . if you have a question or have a comment, just post a comment here and when I see the email notification I will answer back here as quickly as I am able . . . /QB]

Dear Myles, Have enjoyed reading your posts and have learned from them. Thank you. My questions regard an older solid state amp. I purchased a Polytone Mini-Brute amplifier. However, this is an older model, head only, no speakers. I think that it is a PA application. However, it has instrument inputs only, and no XLR. It has three channels and one line out. I bought this at an auction very cheap, sound unheard. It is one of the black velour models, pre vinyl tolex. My questions follow: Is the line out an instrument line, or a speaker line, meaning what kind of cable would I use to connect to a speaker? What ohm rating would be the proper match in a speaker cabinet? Does it matter whether it is 4 or 8 ohms? Thanks for having this post. Best regards!

Gearasameanstoamusicalend,

 

All the Polytone amps I have ever seen had about 110 or so watts of output.

 

They are considered by a lot of folks to be one of the finest amps for Jazz and acoustic guitars around.

 

The line out is is to run to a board, with a line level output. It is not a speaker driving output.

 

The amps I have all seen have a speaker output, and these are solid state output sections that work very nicely at any impedience, as long as it is not less than 2 ohms.

 

I hope this was of some help. I am not aware of any of these amps that were just preamps without a speaker output.

 

Regards,

[myles_rose]

Originally posted by sgguitarzz:

Hey Miles. I am hoping you can help me. I was hoping you can give me some tube advice for my Boogie Mark IIB. It sounds okay but we are all always looking for better. It has the 60/100 option which I always use on 60 which is still too loud anyway. I use it with two Reverend Alltone 1250's (one internal and one external). I really like these speakers. Great versatile and warm sound. It also has reverb and equalizer. I was using 4 JJ 6L6GC's for the power tubes but switched out the outer two and replaced them with THD Yellowjackets. My preamp tube setup is as follows:

 

V1 - Telefunken ECC83

V2 - Mullard CV4004

V3 - Brimar CV4004

V4 - Telefunken ECC83

V5 - RCA 5751

 

Any comments or suggestions would be appreciated. I play classic rock so I need to cover a lot of sounds and I cannot go too far in any one direction. Also, my main guitar is a 69 Gibson SG backed up with a newly aquired PRS Santana SE which I like. Finally, I use a pedalboard with various effects such as wah (Teese RMC1), overdrive/distortion (Visual Sound J&H), chorus/echo (Visual SOund H20), EQ (Dano Fish & Chips), Flanger (Ibanez FL9), Phaser (Akai Intelliphase) and booster (MXR micro amp).

Sorry for the long post. Thanks.

 

Dennis

Dennis,

 

First off its mYles .... not related to Miles Davis

 

Second ..... don't worry about the length of your post, nobody is charging by the line here

 

I like specific posts like this.

 

Okay .... lets take a crack at this.

 

The Mesa Mk IIB is a terrific amp, and a workhorse. It can withstand a ton of abuse and toleraltes impedience mismatches better than a lot of others. The bad aspect of these amps are twofold:

 

1. Way too loud

2. Way too heavy when you get fooled by their size!

 

Even in the 60 watt setting, you are only dropping the volume by about 2 1/2db, so that is not too much help in making them quiet. I know a lot of folks these days that use the THD Hotplate with Mk. series amps.

 

Your Reverend speakers make the problem worse, as these are really articulate speakers and they have a really broad sound dispersion, and are efficient to boot. Your amp in the 60 watt setting with only one of these is about 5-7db louder than a Marshall 100 watt #1959 full stack, so again, you are in sonic db violation territory with most local enforcement laws.

 

The JJ's continue to make things worse in this aspect. JJ's are VERY strong tubes, and at least with Mesa tubes, they are in a range where the amp runs cool, and is down at least 20 watts from what you are probably putting out. If when you bought the tubes you told them they were for a Mesa amp, a smart cookie would have given you tubes to get the amp into a warmer range, and the drawback of that in your case, is even more power. A Mk III that I looked at recently at a clinic was putting out over 145 watts with JJ's in it.

 

The yellow jackets will help over the amp in its full on config, but you still have to contend with the fact that your 60 watt section is probably putting out over 75 or close to 80 watts. Be sure to swap these JJ's with the other two that are removed, so they wear evenly ever once in a while.

 

V1 - Telefunken ECC83

This is always a great choice, but they can be microphonic in these amps. If yours is quiet, then it probably has a bit less gain than some others in the same family, which will help. The ECC83 to me is a bit bright in your amp. You may want to try a 12AX7C, which will tone down the brighness, and keep that nice tube in a drawer or for special occasions.

 

V2 - Mullard CV4004

This is also a great tube, but with the gain cascade circuit, if its a strong example, you may find that with your volume 1 at 3 and your volume 2 at 4-5, you are already getting so much drive, that the articulation and sparkle starts to go away and you need to raise your presence. I would like to be able to test each of these tubes, and I'd take the one with the lower gain and slower rise time, put it in V2, and a 12AX7C in V1 with about a 90 rating (a way I grade tubes for my clients). On your V1 I would want a rating no higher than 80. That gives a nice usable gain over a wider range, say up to 6 on volume 1 and 6 on volume 2.

 

V3 - Brimar CV4004

This is fine, but this is not really in the tone generation stage, so a nice tube like this can be replaced with a less expensive tube.

 

V4 - Telefunken ECC83

I'd also remove this and use a 12AX7 or 12AX7C for the same reason as V3.

 

V5 - RCA 5751

This is a step in a good direction. The 5751 typically has about 70% of the gain of some 12AX7's but does not have the current drive of a 12AT7. You may want to try a 12AT7 here, which will give you the basic gain structure of the 5751 but give you more headroom in the process.

 

Perhaps try this 5751 in V1 and then V2 and see how that sounds to you.

 

One very important aspect of V5, is that you want the A and B sides to be equal in spec. Mesa's really sing with a matched output section, and die almost as badly as some class A amps when this is not a close match. You can get matched phase inverters from Watford Valves in the U.K., but for now, they are one of the few folks that do this. Do not rely on folks that say they can match on a common tester, as these testers work on a static voltage and static bias, and that is NOT how guitar amps work. It may look matched at the static setting, but in real life, the curves will not be the same. This is also the same sort of problem I see all the time with output tubes that were matched in a static state. They work very very well, but when you listen to those amps that ring, sing, and sustain at all levels all over the fretboard, these are the ones I end up finding have a very balanced output section.

 

The above starting points will let you cover a wider sonic ground, but in the classic rock area, you will have more articulation and definition.

 

The 69 SG could not be a better match for this amp. These amps like 10k and up pickups plugged into their input jack! With single coil pickups, I do things a little different on the V1 tube to try to compensate for single coil pickups.

 

Your Santana is also a cool match, but your amp likes the Dragon II PRS pickups a bit better for some styles, but the SE pickups to my ear are better than the ones in the PRS 24 series guitars. In any case, any humbucker or PRS pickup sounds great in this amp.

 

If you are getting any hum that is bothersome, drop me another post, as there is something we can do about that too.

 

If you find you are loosing highs from your pedal board .... (try the guitar alone, then plug it in with effects and see if you miss highs), let me know that too, as there is something we might be able to do about that too, but with those JJ's, you probably are not lacking in the treble department!

 

Regards,

[myles_rose]

Originally posted by freddynl:

Hello Miles,

I could not find the answer with the search so I guess the question was not asked yet.

It looks like I will start with some gigging after 20 years of absence..

Now I undusted an old fender concert amp (1983 black faced- 60 watts rms) I still had in a corner.

It probably needs some new tubes.

So my question is what tubes would you recommand for this amp, to get as clean as possible!

(I will use it for jazz so I don't want dirty output )

 

Thanks for advice,

 

Fred

Fred,

 

If your amp has sat unused for a few years, the filter caps in the power supply need to be checked as they probably dried out.

 

A good tech can check this pretty quickly for you with a capacitor checker. They should also be inspected visually to see if the weep hole has stuff coming out of it, as this is what is supposed to happen when they go bad.

 

If they are on their way out, this can be checked by having a tech check the noise floor on your amp using a scope. This is pretty easy, it is something we do at the amp clinics as part of our normal routine.

 

Your tubes may be just fine and dandy. Can you write back at some point and tell me what they are?

 

If they do need replacement, the tubes that sound the most like Fender in the days of Fender in these amps and the earlier 60's blackface amps to most of my clients are the Tung-Sol 5881 NOS tubes. You can get these from Groove Tubes in the USA and Watford Valves in the UK. To keep the amp clean, you want something with a rating the same as about a Groove Tubes #7 rating.

 

If your old tubes are good or if you stick in new ones, be sure to have your bias checked and adjusted if necessary. Your Concert is one of the amps designed by Paul Rivera, and is a pretty strong amp. The best place to start with bias is at about -50 volts.

 

Make sure if you change the output tubes, you also put in a fresh 12AT7 in the phase inverter position. If there is a 12AX7 in there now, somebody changed it, and get rid of it. Make sure to get a balanced or matched phase inverter. This tube is V7 on your tube chart.

 

V1 and V2 should be 7025's and not 12AX7's.

 

These amps can have up to 500 volts on the plates (B+ voltage) so should not be looked at by a tech in the same way as a Concert with the earlier AB763 circuit, as they had abot 40 volts less on the plates.

 

Spray in all the pots with a good tuner cleaner/lube, not just contact cleaner, or the pots may stick and freeze up.

 

Let me know if you need any more help. Let me know how it turned out.

 

If you are in the Los Angeles area, I would be happy to check your amp and the caps for free at the upcoming amp clinic on May 11th. Details are on my website.

 

Regards,

[jetboy]

Myles,

 

you are amazing, I'm just getting back into all this after some time off for kids, I'm finding all kinds of info both here and at harmony-central. Can't imagine how you keep up.

 

Anyway, like I said, just getting back at this. Traded some old gear that I didn't need/want and bought a new rig. A Badcat Cub Reverb, a 15watt class A. 2 EL84's, 2 12AX7's in the preamp, a 5AR4 rectifier and a 12AX7 phase inverter. I like the amp and to me it sounds pretty darn good as is, however in reading some reviews about it, other users are replacing the OEMs with NOS tubes and they claim major improvement. Well I'm all for that but not so sure where to put the $.

 

Badcat supposedly uses a Chinese 5AR4 and ruby tubes for the power section, not sure about the preamp section.

 

After reading/lurking most of the amp section at HC seems like some NOS tubes would give an improvement but where should I start?

 

The rectifier seems like a logical choice since there seems to be agreement that the Chinese tube is less than stellar and maybe a NOS tube in V1.

 

Any thoughts on this? Seems like I could spend another $200+ and retube the Cub with all NOS but that seems like overkill at least for what I do/want.

 

Am I just experiencing major GAS from reading all this stuff about amps again?

 

thanks so much for all the time you spend on the boards giving out so much info to the uniformed.

 

Mark

[myles_rose]

Originally posted by jetboy:

Myles,

 

you are amazing, I'm just getting back into all this after some time off for kids, I'm finding all kinds of info both here and at harmony-central. Can't imagine how you keep up.

 

Anyway, like I said, just getting back at this. Traded some old gear that I didn't need/want and bought a new rig. A Badcat Cub Reverb, a 15watt class A. 2 EL84's, 2 12AX7's in the preamp, a 5AR4 rectifier and a 12AX7 phase inverter. I like the amp and to me it sounds pretty darn good as is, however in reading some reviews about it, other users are replacing the OEMs with NOS tubes and they claim major improvement. Well I'm all for that but not so sure where to put the $.

 

Badcat supposedly uses a Chinese 5AR4 and ruby tubes for the power section, not sure about the preamp section.

 

After reading/lurking most of the amp section at HC seems like some NOS tubes would give an improvement but where should I start?

 

The rectifier seems like a logical choice since there seems to be agreement that the Chinese tube is less than stellar and maybe a NOS tube in V1.

 

Any thoughts on this? Seems like I could spend another $200+ and retube the Cub with all NOS but that seems like overkill at least for what I do/want.

 

Am I just experiencing major GAS from reading all this stuff about amps again?

 

thanks so much for all the time you spend on the boards giving out so much info to the uniformed.

 

Mark

Mark,

 

For being out of this for a long time, I have to say that when you got back into it, you sure did it right!

 

I am very familar with the Bad Cat line, and I have talked to Mark Samson now and then about the Bad Cat line he developed as their designer. In the area of Bad Cat, there are a few differences from the Matchless in the DC-30 type amp, that are slight and subtle, but I don't see how these two companies compete, as they are all Mark Sampson amps any way you look at it.

 

In any case, your particular amp is perhaps my favorite of the entire line. I like it a bit more than the Matchless version mostly because of the addition of reverb over the older Matchless.

 

Your amp sounds pretty great the way it is. There is not a lot to do to them.

 

In the case of the Chinese rectifier, these have over a 50% failure rate, but the failures are usually in the first hours of use. If you have more than a week or so on your amp, you are probably fine. The Russian Sovtek rectifier is a more sturdy part, but if you are not having problems, I would just leave it as it is.

 

On your output EL-84's .... look at them, and if they are the Sovtek's and not the JJ's, you may want to get a set of the JJ's. They are much better tubes, and in this amp, you want them to be closely matched. The best place for these is Eurotubes. They are at www.eurotubes.com and you may want to call there and ask to speak to Bob Pletka. He is the owner, and sells these tubes for what is probably less than anybody I can think of, $15.00 for a pair. He will match them really closely, much closer than most folks.

 

You can also ask him if the new JJ GZ34 rectifier is available, and if it is, that might be a nice consideration for a spare or replacement, as it will raise your plate voltages a bit and give you even more output.

 

In V1, there are so many choices, it all boils down to personal preference. There are a lot of NOS tubes that are rationally priced, such as the RCAs, GEs and others at times.

 

In these amps, a nice ECC83 is always super for the VOX sound, and then have a 12AX7C to smooth things out for more blues if you like.

 

There are lots of things one can do to improve most amps, but in the case of yours, there is not much left to do. It was done right from the get-go. Mark Sampson used to hand pick tubes for his Matchless amps, but stopped doing that when he had Matchless because people would get the amps home and start to swap things all around.

 

So, at this point you are into the changes for $15.00 for a possible new set of output tubes, and probably less than $20 for a rectifier. I guess at about $35 we are below your $200 limit

 

Remember, on this amp, you can plug a 5Y3 in the rectifier to drop the voltages and you will also have a different feel to the amp as the rise time for voltage on the 5Y3 is really long compared to the 5AR4. The 5AR4 hits it max voltage in about .12 seconds while a 5Y3 takes almost .5 seconds (a full half a second) to recover to max voltage from 0 volts. It takes about .25 seconds to recover from 200 volts to 300 volts. This makes the amp feel and play a lot differently. You can also use a 5U4 in there, which is sort of a split between the other two.

 

These amps are great in clubs and bars, but they are also a lot louder than their false 15 watt rating. These amps typically put out more than their claimed 15 watts, and remember, these are "class A watts", which technically are the same as class A/B watts, because a watt is a watt, but for various reasons, they seem like "louder" watts. If you ever hear a 30 watt Vox AC-30 compared to an 85 watt Fender Twin Reverb, you will see what I mean. They are both LOUD amps.

 

These are also great in the studio, and much more like the Vox AC-15's that Brits used in the studios so much more often than the AC-30.

 

If your amp is too loud, there are ways to tame that too, just drop me a line.

 

Happy playing, and nice choice.

 

Sorry I could not spend more of your money. next time buy a $300 amp and we'll take it from there and triple its original price with ease .... speakers, transformers, tubes, and hours of replacing parts to middle spec rather than spec at the edge of the envelope, and then adjustments and more adjustments to things like bias (in a class A/B amp) and resistor changes to the preamp tubes to get the proper factory plate voltages, etc., etc., etc.

 

You actually saved yourself a lot with this type of amp, and chances are your grandkids will play it someday as a "vintage" amp from the 20th century, or the turn of the 21st century.

 

Regards,

[sgguitarzz]

Thank you Myles (got it right this time). I appreciate your very detailed response. You make reference though to my use of the JJ tubes but actually I am really not using the JJ's 6L6's. I replaced the two outer tubes with the Yellowjackets (which are using JJ EL-84's) and the two JJ's on the inside are not really used in the 60 watt position (I believe they are kind of in standby) so I do not think they have any influence on the sound.

I will try your suggestions on moving the 5751 to the V1 or V2 spot. I mostly use the clean channel anyway so I guess V1 would be more appropriate. I will also look into getting a matched 12AT7 for the phase inverter from Watford Valves. Any suggestions for which one? I have one or two 12AT7's around to replace it with for now. Also, any suggestions for the 12AX7C's? How do these differe from the 12AX7?

As you said these guitars do sound nice with this amp. I will probably upgrade the pickups in the Santana with something stronger. You mentioned the PRS Dragon II's. I was thinking of a set of Rio Grandes (Texas for the neck and BBQ for the bridge). What do you think about this?

The amp is very quiet. The only time I had a hum was in the reverb circuit once which turned out to be a bad tube.

I do love these Reverend speakers but they are very efficient. What would be a better match and would the difference be worthwhile?

I know I have asked a lot of questions. I do appreciate your time and expertise.

 

Dennis

[TurboDog]

Heya Myles,

 

I had a chance to get an old Martin amp from a local music shop. It was only $150, but I passed. My friend who works there snatched it up and still has it.

 

Do you know anything about the old Martin amps? I can find no info whatsoever. I remember hearing that they were made for Martin by somebody else.

 

It's a small amp, with maybe an 8" or 10" speaker. It was very simple. I played it, and remember it having a sweet tone. I have no clue what tubes it used or anything.

 

I may could get thios amp off my friend, but he's been offered some decent money for it.

 

Any info?

 

Oh, and thanks for the EL34 test results. I'l be retubing my Rivera 30-12 soon and will take all your results into account. I can get EH's pretty cheap, so I think I'll try them.

[myles_rose]

Originally posted by sgguitarzz:

Thank you Myles (got it right this time). I appreciate your very detailed response. You make reference though to my use of the JJ tubes but actually I am really not using the JJ's 6L6's. I replaced the two outer tubes with the Yellowjackets (which are using JJ EL-84's) and the two JJ's on the inside are not really used in the 60 watt position (I believe they are kind of in standby) so I do not think they have any influence on the sound.

I will try your suggestions on moving the 5751 to the V1 or V2 spot. I mostly use the clean channel anyway so I guess V1 would be more appropriate. I will also look into getting a matched 12AT7 for the phase inverter from Watford Valves. Any suggestions for which one? I have one or two 12AT7's around to replace it with for now. Also, any suggestions for the 12AX7C's? How do these differe from the 12AX7?

As you said these guitars do sound nice with this amp. I will probably upgrade the pickups in the Santana with something stronger. You mentioned the PRS Dragon II's. I was thinking of a set of Rio Grandes (Texas for the neck and BBQ for the bridge). What do you think about this?

The amp is very quiet. The only time I had a hum was in the reverb circuit once which turned out to be a bad tube.

I do love these Reverend speakers but they are very efficient. What would be a better match and would the difference be worthwhile?

I know I have asked a lot of questions. I do appreciate your time and expertise.

 

Dennis

Dennis,

 

I messed up here. I thought you were using the yellow jackets with the other tubes.

 

What you are saying is that the yellow jackets are your source and with the amp in 60 watt mode the other pair are effectively off (actually the B+ is off on these in that setting.

 

Got it.

 

In that case your amp can probably be played without the police making a house call.

 

If you use the clean channel, then you are correct and experiment with V1.

 

Watford carries a number of 12AT7's, but my favorite ones of theirs are the PHILPS and the G.E 12AT7/ECC81 tubes. I think the Philips is less expensive, I do not remember their pricing, but each of these is offered in what they call a "balanced valve" which really makes a nice difference in the phase inverter position.

 

12AX7C's need to be off the new tooling. How you tell this is by looking inside the tube at the top of the tube just under the silver getter flash. If you see a little square or rectangle, than avoid it. If you see a little round halo, then its a better bet. These tubes are darker than non-Chinese 12AX7's, and blues players, slide players, and jazz folks prefer them a lot of the time.

 

One problem with them though, is sometimes their rise time is very fast, too fast for some folks, and that can make them sound almost solid state in nature. This is due to inconsistancy where some of their characteristics are not in a range where they should be in relation to their gain. This is where things get a bit tricky unless you have access to a curve tracer. Maybe when you contact Watford you can ask if you can specify something with a transconductance less than 1650, as this will help.

 

I have not heard the Rio Grande's in the Santana. Maybe somebody that has more experience with them can say something here.

 

Good - your amp is quiet!

 

On your speakers, you could always stick in some inefficient speakers, but these amps sound best with speakers like yours or EV's. They are loud, but they were designed to be. One thing you can do is refrain from using your second speaker. When you double your radiating area, you get a LOT more sound and air moving out there. Save the second speaker for the big arena or something.

 

Regards,

[myles_rose]

Originally posted by TurboDog:

Heya Myles,

 

I had a chance to get an old Martin amp from a local music shop. It was only $150, but I passed. My friend who works there snatched it up and still has it.

 

Do you know anything about the old Martin amps? I can find no info whatsoever. I remember hearing that they were made for Martin by somebody else.

 

It's a small amp, with maybe an 8" or 10" speaker. It was very simple. I played it, and remember it having a sweet tone. I have no clue what tubes it used or anything.

 

I may could get thios amp off my friend, but he's been offered some decent money for it.

 

Any info?

 

Oh, and thanks for the EL34 test results. I'l be retubing my Rivera 30-12 soon and will take all your results into account. I can get EH's pretty cheap, so I think I'll try them.

TurboDog,

 

Valco, Supro, Premier, and Gretsch amps were at times made under the same roof, and perhaps that is where the Martin amps came from too. I don't know.

 

Sometimes I am a vast storehouse of useless information, but there are a LOT of times that I am stumped. This is one of them.

 

You may want to look up Trace from Voodoo Labs, as he's a lot smarter than I am, or talk to Dan Torres over at Torres Engineering.

 

The EH tubes are a nice match in that amp and will make that Rivera a pretty versitile amp. If the price is right, that is always nice too!

 

Regards,

[TurboDog]

Woohoo!!

 

I stumped Myles! Do I get some kind of prize for that?

[myles_rose]

This is a reply I wrote for a fellow over on Harmony Central. Generally I tell people to come over here, as that way it benefits folks here and forms something of a FAQ list, but I did answer this over there and felt it would be of benefit to Marshall folks over here.

 

He initially let me know he had an older Marshall that he wanted to start playing again that had been dormant for a long time.

 

Here it is:

 

quote:

--------------------------------------------------------------------------------

Originally posted by soundelixir:

Agghrrrr....... 3 things I don't have...... So, my Bias Rite Bias King is worthless then? I guess I'll just have to get my tech to install them from now on. Also, he and I have been discussing possible filter cap changes (my amp is 31 years old), and he told me that they are responsible in a large part for the "tone" of the amp. Is this so? So, would there be a cap combination that would more of an "Eddie" tone or an "AC/DC" tone? Well, anyways, it sounds like the JJ's might be right up my alley; I'll probably try them out soon. I'd love to bring my amp to you, but I'm on the east coast and probably won't get to Cali for a while. I really appreciate the offer though!

--------------------------------------------------------------------------------

 

soundelixir,

 

Don't fret! (no pun intended).

 

You can use your bias king, it just takes a few steps to get it right. If you bias out too much of the crossover notch, then the amp sounds too clean and looses the characteristic Marshall crunch.

 

Here is the drill:

 

1. First, measure your B+ voltage. To get an accurate reading, you need to have the tubes in place, because if one is pulled the B+ will rise.

 

2. Once you know your B+, if you are using normal EL-34 tubes, you want to divide 25 by your bias voltage. If you are using E34L or E34Ls tubes, then use a value of 30.

 

3. Lets say we have 450 plate volts off pin 3 of the tube socket as an example. 25/450 = .0555

 

4. Multiply that .0555 by 1000

 

5. That gives us 55.5, which is the maximum idle dissapation of that particular tube in your amp at that B+ voltage for a 25 watt tube.

 

6. Write down your B+ voltage for future reference, as this will not change unless there is some problem, and the more to steer clear of those voltages, the better it is for your health depending on your luck.

 

7. Now we take 50% of the 55.5 as a starting point. That gives us about 28mA. With your volume all the way down, tone controls set to 5, and no input signal, adjust your bias probe to 28.

 

8. Now play the amp with it turned to "7". You can leave the bias probe in place. You will see some big numbers as you play, but ignore all of these.

 

9. If your amp is too clean, then drop down to say 27, 26.5, 26, 25.5 etc., to get the crunch you want.

 

10. If the amp is too dirty, raise it in the same way as above, but go no higher than 36mA or your amp will be running very hot.

 

You may get lucky right off the bat, but your bias king or bias probe can be used, it just takes a bit of time. The benefit is that you get to hear how things change as you make the changes. You may find you prefer a setting that may not be the same setting as you get with a scope anyway. Whenever I adjust bias, I always make folks play, and we rarely end up at our starting point anyway.

 

Filter caps in Marshalls are VERY important. The caps in the tone circuit are also important as they are right in the signal path. Its the bit caps that dry out though, and your tech is right on the money.

 

Now as far as those caps, we are all used to seeing the big blue LCR caps that are about as big as the tubes themselves. There is a new cap around that has the same base and mounting, but they are much shorter, newer, last much longer, and cost less. They are made by the JJ factory, the same folks that make the tubes. In a power supply, 50mf @ 500v is pretty much 50mf @ 500volts, so you have an option here. Talk to your tech about them. Eurotubes sells them, and so does Antique Electric Supply at tubesandmore.com

 

The retail cost on the 50mf caps is $10.95 each and on 100mf caps its $12.95 each from AES. Eurotubes may be cheaper. The LCR's are about $20 each retail. They have a pretty big markup as a lot of folks pay more to have the "blue" caps in their amp as original, but keep in mind the orignal caps can go away in as little as 5 years in a Marshall. The newer caps last much longer.

 

My cost on LCR's is $7.95

My cost on JJ 50mf is $6.55 (if I buy 10 its $5.79)

My cost on JJ 100mf is $8.85 (if I buy 10 its $7.87)

 

Those prices are for each one.

 

Now you have a general idea of markup on cost vs. retail, so you can check what you are being charged when you have work done.

 

Hope this was of some benefit.

 

Regards,

[myles_rose]

Originally posted by TurboDog:

Woohoo!!

 

I stumped Myles! Do I get some kind of prize for that?

TurboDog,

 

Yes.....

 

Free amp checkout at one of our free amp clinics? But there is also free candy there, AND I will buy you a beer or a coke at the bar next door also.

 

Myles

[jetboy]

Originally posted by myles111:

Originally posted by jetboy:

[qb]Myles,

 

For being out of this for a long time, I have to say that when you got back into it, you sure did it right!

 

I am very familar with the Bad Cat line, and I have talked to Mark Samson now and then about the Bad Cat line he developed as their designer. In the area of Bad Cat, there are a few differences from the Matchless in the DC-30 type amp, that are slight and subtle, but I don't see how these two companies compete, as they are all Mark Sampson amps any way you look at it.

 

In any case, your particular amp is perhaps my favorite of the entire line. I like it a bit more than the Matchless version mostly because of the addition of reverb over the older Matchless.

 

Your amp sounds pretty great the way it is. There is not a lot to do to them.

 

In the case of the Chinese rectifier, these have over a 50% failure rate, but the failures are usually in the first hours of use. If you have more than a week or so on your amp, you are probably fine. The Russian Sovtek rectifier is a more sturdy part, but if you are not having problems, I would just leave it as it is.

 

On your output EL-84's .... look at them, and if they are the Sovtek's and not the JJ's, you may want to get a set of the JJ's. They are much better tubes, and in this amp, you want them to be closely matched. The best place for these is Eurotubes. They are at www.eurotubes.com and you may want to call there and ask to speak to Bob Pletka. He is the owner, and sells these tubes for what is probably less than anybody I can think of, $15.00 for a pair. He will match them really closely, much closer than most folks.

 

You can also ask him if the new JJ GZ34 rectifier is available, and if it is, that might be a nice consideration for a spare or replacement, as it will raise your plate voltages a bit and give you even more output.

 

In V1, there are so many choices, it all boils down to personal preference. There are a lot of NOS tubes that are rationally priced, such as the RCAs, GEs and others at times.

 

In these amps, a nice ECC83 is always super for the VOX sound, and then have a 12AX7C to smooth things out for more blues if you like.

 

There are lots of things one can do to improve most amps, but in the case of yours, there is not much left to do. It was done right from the get-go. Mark Sampson used to hand pick tubes for his Matchless amps, but stopped doing that when he had Matchless because people would get the amps home and start to swap things all around.

 

So, at this point you are into the changes for $15.00 for a possible new set of output tubes, and probably less than $20 for a rectifier. I guess at about $35 we are below your $200 limit

 

Remember, on this amp, you can plug a 5Y3 in the rectifier to drop the voltages and you will also have a different feel to the amp as the rise time for voltage on the 5Y3 is really long compared to the 5AR4. The 5AR4 hits it max voltage in about .12 seconds while a 5Y3 takes almost .5 seconds (a full half a second) to recover to max voltage from 0 volts. It takes about .25 seconds to recover from 200 volts to 300 volts. This makes the amp feel and play a lot differently. You can also use a 5U4 in there, which is sort of a split between the other two.

 

These amps are great in clubs and bars, but they are also a lot louder than their false 15 watt rating. These amps typically put out more than their claimed 15 watts, and remember, these are "class A watts", which technically are the same as class A/B watts, because a watt is a watt, but for various reasons, they seem like "louder" watts. If you ever hear a 30 watt Vox AC-30 compared to an 85 watt Fender Twin Reverb, you will see what I mean. They are both LOUD amps.

 

These are also great in the studio, and much more like the Vox AC-15's that Brits used in the studios so much more often than the AC-30.

 

If your amp is too loud, there are ways to tame that too, just drop me a line.

 

Happy playing, and nice choice.

 

Sorry I could not spend more of your money. next time buy a $300 amp and we'll take it from there and triple its original price with ease .... speakers, transformers, tubes, and hours of replacing parts to middle spec rather than spec at the edge of the envelope, and then adjustments and more adjustments to things like bias (in a class A/B amp) and resistor changes to the preamp tubes to get the proper factory plate voltages, etc., etc., etc.

 

You actually saved yourself a lot with this type of amp, and chances are your grandkids will play it someday as a "vintage" amp from the 20th century, or the turn of the 21st century.

 

Regards,

Myles,

 

thanks for the incredible reply, from reading the posts here and at HC I'd say i'm getting advice I should be payin' for so thanks for your dedication to making amps sound better.

 

As for the last part of your post, funny i already did that the year before. I knew I wanted the real deal (TUBES!!!!) and I'd been searching for that full out sound of my former Super Reverb but with a lot less volume. I ended up building a Torres Tiny Tone ($400 + $120 for a small cab and a weber 10) which was fun and it did give me pretty good tone at speaking volume but the versatility wasn't there, no clean tones to speak of and no reverb. Ended up playing it as an effect into my Super (with all the clicks and pops and still too much volume).

 

Bought a pod ($300)and that was better, more versatility and a fake reverb and stopped using with the Super. Still not quite right but closer.

 

Then I had my latest bout of what could only be called male menopause ( I will be 50 this month) I finally decided it was worth the effort and $$. I bought a custom built JET guitar (hence the Jetboy moniker) and traded my '67 SG, which I never really liked as much as I thought I would, for the Bad Cat and sold my '68 Super.

 

Now here's what ever wisdom I can impart to those in NEED of that tone. You can do it the long way or just break out your wallet ;-)

 

So much for the rambling....

 

I pulled the tubes from the Cub and they are all sovteks, and the rectifier is a Ruby. I'm going to order some JJ's and give'm a try. Also after going to your web site and reading the tube tests I decided to go for broke (literally) and order a combination of a NOS mullard 4004 and a NOS ge jan 12ax7 and a set of NOS ge el84's from KCnostubes. I guess I'll find out whether there is real or just poseur (me) tones in this rig, after this it certainly won't be the amps fault.wAN8qE

 

I know there will be some that will moan about dumping the Super, and it was a real nice amp but way too loud for me (the Cub is still too loud but not as bad) and the Super needed some real overhauling, caps and tubes etc.

 

again thanks so much for the help on this and i hope someone is paying you for all the time you spend here and at HC.

 

Like you said, 20 years from now my daughters boy friends will be playing the Cub wondering who will inherit it.

 

Mark

[TurboDog]

Ah Myles,

 

I'm closer to Atlanta, so I'll have to take a raincheck. Sooner or later you'll get to our neck of the woods and me and Chip and a few others will pay a visit.

 

Actually with all of your advice, I will be buying you a few beers.

 

Hey, how safe would it be for me to turn the bias down a hair and just drop some new EH's in there? I know there are some amp techs areound, but I don't know any and I'm afraid I'd be ampless for a few days.

[sgguitarzz]

Hey Myles. Thanks for the tips. I was able to pick up two of the GT 12AX7C's at Sam Ash ($14 each). I checked and the both have the round halo thing under the silver getter flash. I was amazed SA had them. I will try putting the 5751 in V1, 12AX7C in V2 & V4, and put a 12AT7 in V5 (I have an Amperex Bugle Boy and a JJ to choose from). I will switch out the V3 Brimar and replace it with a JJ 12AX7 I have. I guess we will see what happens.

As far as using one speaker the problem is the Alltones can only handle 50 watts and the Boogie is on the 60 watts setting. That is why I always used the two speakers.

I have a gig Saturday night so it will be a good test.

 

Dennis

[freddynl]

Many thanks for your advice Myles, I am pretty sure I could not have these advices easily in

netherlands, in fact I would not know where to find a capable technician for these amps.

 

Originally posted by myles111:

 

If your amp has sat unused for a few years, the filter caps in the power supply need to be checked as they probably dried out.

 

----

Initially when I switched the amp on, there were a lot of crackles, which made me turn it off and send my post to you.

Now I did switch it on again today and only a few crackles, which were gone within a few minutes.

They did not come back.

Crackles came back as soon as I plugged a guitar, and after some moving a bit of the inputjack to get some possible corrosion off hence crackles gone as well..

The sound is as clear,warm and dynamic as I could remember.

In fact I played last night on a practice with the other guitarists amp, a line6 modular whatever it is, I could not get it sound like I wanted. just cold/metallic sound.

I really thought that I had it wrong (nobody complained, anyway about the sound) but when I am now listening to the concert amp..I can tell you these modular amps don't come even close...

 

So it looks like it just needs some cleaning of pots and cleaning of input contacts like you said

 

-------------

A good tech can check this pretty quickly for you with a capacitor checker. They should also be inspected visually to see if the weep hole has stuff coming out of it, as this is what is supposed to happen when they go bad.

----

wright this is something to cheque on

 

-----

If they are on their way out, this can be checked by having a tech check the noise floor on your amp using a scope. This is pretty easy, it is something we do at the amp clinics as part of our normal routine.

 

Your tubes may be just fine and dandy. Can you write back at some point and tell me what they are?

 

----

I think by now they are in great condition.

This is what's written on the tubes by the way;

Fender special design

023556 (30,11,23) ACS

-----

 

If they do need replacement, the tubes that sound the most like Fender in the days of Fender in these amps and the earlier 60's blackface amps to most of my clients are the Tung-Sol 5881 NOS tubes. You can get these from Groove Tubes in the USA and Watford Valves in the UK. To keep the amp clean, you want something with a rating the same as about a Groove Tubes #7 rating.

 

If your old tubes are good or if you stick in new ones, be sure to have your bias checked and adjusted if necessary. Your Concert is one of the amps designed by Paul Rivera, and is a pretty strong amp. The best place to start with bias is at about -50 volts.

 

Make sure if you change the output tubes, you also put in a fresh 12AT7 in the phase inverter position. If there is a 12AX7 in there now, somebody changed it, and get rid of it. Make sure to get a balanced or matched phase inverter. This tube is V7 on your tube chart.

there's no tube with 12ax7.

In fact I bought this amp new myselve in 1983 and I never replaced any tube, so it is in original state. (even the control cheque card before it leaves the factory was in it.)

 

V1 and V2 should be 7025's and not 12AX7's.

 

----

there is 7025 on most of the preamp tubes. (7x)

I could not read four of them, And I did not

want to pull them out as the amp is fine so far and I could not pull them out without using heavy force, which I like to avoid if not needed.

 

-------

Spray in all the pots with a good tuner cleaner/lube, not just contact cleaner, or the pots may stick and freeze up.

 

----

wright,,, mmm. this means I have to unmount the amp to get there..

as soons as it start's crackling will do that..

thanks.

----

Let me know if you need any more help. Let me know how it turned out.

 

----

If you are in the Los Angeles area, I would be happy to check your amp and the caps for free at the upcoming amp clinic on May 11th. Details are on my website.

 

I whish I was, but there's a long distance between netherlands and L.A.

 

Regards,[/QB]

Thank's again

Fred

[myles_rose]

Originally posted by TurboDog:

Ah Myles,

 

I'm closer to Atlanta, so I'll have to take a raincheck. Sooner or later you'll get to our neck of the woods and me and Chip and a few others will pay a visit.

 

Actually with all of your advice, I will be buying you a few beers.

 

Hey, how safe would it be for me to turn the bias down a hair and just drop some new EH's in there? I know there are some amp techs areound, but I don't know any and I'm afraid I'd be ampless for a few days.

TurboDog,

 

You can be pretty safe in the bias area. There is normally a pretty wide range where tubes will run safely.

 

With the amp off, find the max and min ranges of your bias pot, set it in the middle, and then after a few minutes of tuning on and running, just make sure the outer plate structure is not glowing red or orange. If the amp sounds fine enough, you may not be where is best for sound, but it will get you by. You may even like it just fine and want to leave it there.

 

As far as Atlanta, that is a possibility this summer along with D.C./Virginia, Orlando, and New Orleans.

 

Regards,

[sgguitarzz]

Just a suggestion - come to NYC. We could use you here also. I will be first in line .

 

Dennis

[myles_rose]

Originally posted by sgguitarzz:

Just a suggestion - come to NYC. We could use you here also. I will be first in line .

 

Dennis

Dennis,

 

Well, unless it was in the line of work already there or a vacation, you'd have to talk to some store about paying my travel and expenses out there

 

Besides, on the East Coast you guys have Trace over at Voodoo!

 

Regards,

[myles_rose]

Originally posted by freddynl:

Many thanks for your advice Myles, I am pretty sure I could not have these advices easily in

netherlands, in fact I would not know where to find a capable technician for these amps.

 

.... cutting by Myles for brevity ....

 

I whish I was, but there's a long distance between netherlands and L.A.

 

Regards,

Thank's again

Fred[/QB]

 

Fred,

 

You are on the right track. As far as the codes on the tubes, they are usually batch codes and date codes, but the best way to tell what they really are is to look at them.

 

Just clean those pots and jacks when you get the time, and the tube sockets too.

 

By the way, from September 1969 to November of 1970 I live in Holland ... in Amsterdam, on the canal (Singel) at 27 Singel. It was great. If the Paradiso is still there, drop in for me

 

Regards,

[jetboy]

Hi Myles,

 

after reading everything I could find, I went crazy (must be the old age) ordered the NOS tubes including a mullard 4004 and a NOS GE 12ax7 and el84's and THEN ordered some JJ's from Bob at Eurotubes. The JJ's are a balanced ecc83 for the phase inverter and a variety of graded ecc83's with a set of lower value el84's to reduce some volume on the Bad Cat. Man I'll have enough tubes to last a lifetime, at least my lifetime.

 

Too much info!!!! I guess the analysis part of all this got to me, I'm just gonna try'em all and see what I like.

 

I figure ultimately it will be cheaper now then later and I'll pretty much know the limits of the Bad Cat and will be able to decide for myself whether all this NOS stuff is for real or just for people (like me I guess) with too much time on their hands.

 

Harkens back to my youth where I spent way too much time thinking about hifi gear ;-) or my (current) other hobby/job Mac computers.

 

talk about anal..... I'm starting to think like the posters at HC, looking for the holy grail. good thing I still have some $ left over from selling my Super. My kids will just have to allow their ol' dad a few eccentricities and a little less inheritance.

 

the Torres was fun, I probably should rewire some of it to reduce the hum a bit but it was as you said a real learning experience, especially learning the hard way about capacitor discharge, wahooooo.

 

I felt the same way about the SG, it was what I wanted BAD in high school, I settled back then for an Epi w/ 2 mini buckers but that neck was even worse as far as neck play... I finally got my '67 to celebrate my 2nd daughter's birth but the reality was not as good as the dream. Turns out that one of the PU's had a short and was a single coil (previous owner removed the covers) I never realized it, so maybe I just didn't get the best it had to offer. The guy I traded it to for the Bad Cat sent the pu's to lindy fralin to get rewound. Looks like he's fixing it up to get some real $$$ for it. Maybe you'll see it on Ebay or someplace like that.

 

Same thing with the '78 Les Paul I got when my 1st daughter was born, I can now say I had one but it was also less than I expected and I traded it for some computer gear.

 

As you can probably tell I've been at this off and on for a long time and it pretty much coincides with times of major change in my life... some people opt for comfort food I seem to opt for the comfort of music. I suppose/know if I had the talent I would opt for a career somewhere in the biz.

 

Anyway thanks again for your advice and for the friendly conversation. The business may be nasty but you still meet some mighty nice people in it.

 

Mark

[myles_rose]

Originally posted by jetboy:

Hi Myles,

 

after reading everything I could find, I went crazy (must be the old age) ordered the NOS tubes including a mullard 4004 and a NOS GE 12ax7 and el84's and THEN ordered some JJ's from Bob at Eurotubes. The JJ's are a balanced ecc83 for the phase inverter and a variety of graded ecc83's with a set of lower value el84's to reduce some volume on the Bad Cat. Man I'll have enough tubes to last a lifetime, at least my lifetime.

 

Too much info!!!! I guess the analysis part of all this got to me, I'm just gonna try'em all and see what I like.

 

I figure ultimately it will be cheaper now then later and I'll pretty much know the limits of the Bad Cat and will be able to decide for myself whether all this NOS stuff is for real or just for people (like me I guess) with too much time on their hands.

 

Harkens back to my youth where I spent way too much time thinking about hifi gear ;-) or my (current) other hobby/job Mac computers.

 

talk about anal..... I'm starting to think like the posters at HC, looking for the holy grail. good thing I still have some $ left over from selling my Super. My kids will just have to allow their ol' dad a few eccentricities and a little less inheritance.

 

the Torres was fun, I probably should rewire some of it to reduce the hum a bit but it was as you said a real learning experience, especially learning the hard way about capacitor discharge, wahooooo.

 

I felt the same way about the SG, it was what I wanted BAD in high school, I settled back then for an Epi w/ 2 mini buckers but that neck was even worse as far as neck play... I finally got my '67 to celebrate my 2nd daughter's birth but the reality was not as good as the dream. Turns out that one of the PU's had a short and was a single coil (previous owner removed the covers) I never realized it, so maybe I just didn't get the best it had to offer. The guy I traded it to for the Bad Cat sent the pu's to lindy fralin to get rewound. Looks like he's fixing it up to get some real $$$ for it. Maybe you'll see it on Ebay or someplace like that.

 

Same thing with the '78 Les Paul I got when my 1st daughter was born, I can now say I had one but it was also less than I expected and I traded it for some computer gear.

 

As you can probably tell I've been at this off and on for a long time and it pretty much coincides with times of major change in my life... some people opt for comfort food I seem to opt for the comfort of music. I suppose/know if I had the talent I would opt for a career somewhere in the biz.

 

Anyway thanks again for your advice and for the friendly conversation. The business may be nasty but you still meet some mighty nice people in it.

 

Mark

Mark,

 

It does sound like you put together a nice tube inventory. What you will find in almost all probability, is you will like the 4004 for some things and the GE for others, and you will find yourself swapping tubes every so often, somewhat like folks change patches on a modeling amp Your amp really responds to different tube characteristics in V1. I think you will like the surprises and changes.

 

Bob at Eurotubes is a terrific fellow, and when it comes to output tubes, he already gets something of the "cream of the crop" from the factory as he has family back there and is thought of as part of the JJ family because his real family is from the area. Then he takes these tubes that were already hand picked for him, and goes through them himself, and matches them even closer. His output sets are typically matched within 1mA, and on an EL-84 that is a 98% match on a average characteristic tube. Usually a match of 90% is considered pretty good, and anything at 95% or over, and your output section gets nicer on something of an exponential scale on class A amps like Matchless and Vox types, and is even more apparent on Dr. Z. amps.

 

The NOS tubes are different. Whether that is good, bad, or whatever, is up to the listener. The GE's are really terrific but pricy. What you will hear there, is when you are at high levels with a lot of output distortion, you will still be able to hear individual notes within a chord as an example. At low levels, there is more texture and complexity where the amp appears louder and more full at reduced settings. If you want to hear a DRAMATIC difference, even for folks that think they have no interest in music or sound, plug in your GE's play a bit, and then replace those with Sovtek EL-84's. It sounds like a big felt blanket was tossed over the top of your amp.

 

But ... if you get the sound you are after, have effects and pedals in the front end, and are happy with what you get with inexpensive tubes that are easily available, then that's terrific, and less expensive! Some of the best sounds in the world are on very inexpensive amps with cheesy effects that are just magic. I have one of those little plastic Vox AC-1 amps. It gets used for a lot more than most could imagine. I also have a modified 100 watt Rivera Fandango head with a ported CS-410 cabinet, a sub system, and a 4x12 cabinet, running hand picked 6L6GC's and is fully blueprinted. It puts out about 170 watts max, and gets used less than anything else I own.

 

On your interest of Mac computers. I used to do a lot with them a decade or so back. I was the music consultant for Apple on the Vivarium project and worked for Alan Kay's group.

 

Stay away from those caps, and on pins 2 and 5 of preamp tubes on your Torres, get those wires off the chassis as much as you can, and that will get rid of a lot of your hum issue.

 

Working in the music biz is great at times, but like any other sort of job, can be a JOB at times. I worked in corporate environments for a few decades, since 1973, when I started with Control Data right out of school. I prefer this work, although financially it is more chicken and less steak, but I have never been as broke or as happy in my life.

 

Regards,

 

Myles