Feel free to ask Myles

[RoughDraft]

My amp is a Reverend Hellhound. You may not know much about it since its not too popular. The website states that in order to change to EL-34 there is some kind of mod done. Also the amp is fixed bias.

 

Jon

[rsf1977]

Ok there is something wierd going on now.

 

I put all the original meas 12AX7s back in and everything sounded whisper quiet and perfect. So then I began checking all my EH12AX7s to try and fing the one that was causing the hum. It seems that most of them are humming when I have it set to the clean channel (which is actually the Red Modern channel cloned with the clean switch on, if that means anything). Some are blatant offenders and others have a slight hum to them. I had to try all the tubes one-by-one in the v2 slot cause the v1 only uses one side of the tube. But it seems that they all go whisper quiet except one when it's on channel 2 the high gain channel but on the clean channel is where the problem seems to be hapening.

 

So what do you think is happening or happened to my preamp tubes. Again this all started happening when I swapped in the Groove Tube GE6L6s (6 rating) could they have over loaded them or something. I have a show this Sat. night and this is starting to stress me out. What should I do.

[myles_rose]

Originally posted by RoughDraft:

My amp is a Reverend Hellhound. You may not know much about it since its not too popular. The website states that in order to change to EL-34 there is some kind of mod done. Also the amp is fixed bias.

 

Jon

Jon,

 

I know these amps, they are not too popular because Reverend does not flood the advertising market, and has a home waiting for every amp they make.

 

The mod is to change the bias, so it would be best to contact Reverend directly and ask them what resistor change(s) need to be done.

 

Myles

[myles_rose]

Originally posted by rsf1977:

Ok there is something wierd going on now.

 

I put all the original meas 12AX7s back in and everything sounded whisper quiet and perfect. So then I began checking all my EH12AX7s to try and fing the one that was causing the hum. It seems that most of them are humming when I have it set to the clean channel (which is actually the Red Modern channel cloned with the clean switch on, if that means anything). Some are blatant offenders and others have a slight hum to them. I had to try all the tubes one-by-one in the v2 slot cause the v1 only uses one side of the tube. But it seems that they all go whisper quiet except one when it's on channel 2 the high gain channel but on the clean channel is where the problem seems to be hapening.

 

So what do you think is happening or happened to my preamp tubes. Again this all started happening when I swapped in the Groove Tube GE6L6s (6 rating) could they have over loaded them or something. I have a show this Sat. night and this is starting to stress me out. What should I do.

The output section would not affect your preamp section. The #6 rating is the same as Mesa's top two ratings of their six scale system.

 

Mesa amps are high front end gain amps, and the most critical tube is V1, as any noise with it, will be sent and amplified down the signal chain.

 

I would find the MOST quiet of your 12AX7 preamp tubes and put that in V1.

 

If that is not quiet enough, then let me know. Also let me know again what happend on what channel.

 

Myles

[johnny5]

i have Reverend Hellhound combo (2 6L6's, 60W, 1X12) that has Electro Harmonics 6L6's in it. i have read that these tubes are not very good. and in listening i notice that when these suckers are pushed, they get less and less sweet. almost flabby. i was looking the groove tubes site at the CB's looks like i can get a little more power tube distortion out of those.

 

any thoughts or recomendations?

[myles_rose]

Originally posted by johnny5:

i have Reverend Hellhound combo (2 6L6's, 60W, 1X12) that has Electro Harmonics 6L6's in it. i have read that these tubes are not very good. and in listening i notice that when these suckers are pushed, they get less and less sweet. almost flabby. i was looking the groove tubes site at the CB's looks like i can get a little more power tube distortion out of those.

 

any thoughts or recomendations?

johnny5 ...

 

The CB's are Chinese with a softer vacuum, but do have more mids than the EH's .... most 6L6 tube actually do.

 

In your amp my favorite tube is the KT-66HP, that is also now one of the least expensive in the GT line as we dropped price from $85 a duet to $60.00 a duet ( $5.00 cheaper than the Chinese KT-66 we also carry with the price drop now ).

 

I like these with a #5 rating in your amp and in the Dr. Z Route 66 amp (that was designed around this particular tube if you check with them). I also use this in a JTM-45 and a GT Solo 45.

 

Myles

[rsf1977]

ok when the buzzing originally started it was equal on both channels with all EH12AX7s in. Then I replaced them with the original stock mesa 12AX7s and it was perfectly fine. Then in the V2 position I started swapping in and out all my EH12AX7s to try to find the bad one(s). So I then started to notice that all of them had a certain hum, one of which was really bad. The only thing was all but one I believe hummed on the clean channel and then was whisper quiet on the high gain channel. It seemed like the clean channel was not liking the EH12AX7s all of a sudden. But no problems with the Mesa 12AX7s in either channel.

 

Any Ideas?

 

Oh and I forgot I had aNOS Mullard ECC83 in the V1 position which as I remember now when I switched it back to the EH12AX7 was at the same moment I switched to the GE6L6 could the mullard have screwed the rest of the tubes up some how?

[ManInTheBox]

Hey Myles,, do you ever get tired of answering all these questions? I see we keep you pretty busy.

Just in case your answer is no(you don't ever get tired). I am sure you have answered this question many times before, but how do you know when it is time to change a tube? I ask this, because I have a Crate blueVoodoo 6212 combo. I bought it about eight years ago, because it had an awesome clean channel, and a helacious overdrive channel. I would say the clean sounded very Fender, and the dirty definitely had the hot rodded Marshall sound. Back then, it was almost unheard of to get that in one amp. Anyhow, I changed the output tubes on the thing about two years ago, and then the preamp tubes this year, and I just don't hear the Magic in the clean channel that it used to have. It was there before I changed the preamp tubes. Anyhow, now it is very Bright, and I can hear the attack on the strings, it is very painful at loud volumes. I was thinking about going back with the old tubes one by one, until I found one that I liked, but I keep thinking that if they were bad, they were bad, and I don't know if this will help. I don't know much about tubes, so going into a store and asking for a specific one seems kinda scary to me.

[johnny5]

Originally posted by myles111:

Originally posted by johnny5:

i have Reverend Hellhound combo (2 6L6's, 60W, 1X12) that has Electro Harmonics 6L6's in it. i have read that these tubes are not very good. and in listening i notice that when these suckers are pushed, they get less and less sweet. almost flabby. i was looking the groove tubes site at the CB's looks like i can get a little more power tube distortion out of those.

 

any thoughts or recomendations?

johnny5 ...

 

The CB's are Chinese with a softer vacuum, but do have more mids than the EH's .... most 6L6 tube actually do.

 

In your amp my favorite tube is the KT-66HP, that is also now one of the least expensive in the GT line as we dropped price from $85 a duet to $60.00 a duet ( $5.00 cheaper than the Chinese KT-66 we also carry with the price drop now ).

 

I like these with a #5 rating in your amp and in the Dr. Z Route 66 amp (that was designed around this particular tube if you check with them). I also use this in a JTM-45 and a GT Solo 45.

 

Myles

myles,

can i just directly replace the EH's with the KT's with out changing anything (considering the amp does not have a bias adjustment))?

 

thanks for the tip,

john

[myles_rose]

Originally posted by rsf1977:

ok when the buzzing originally started it was equal on both channels with all EH12AX7s in. Then I replaced them with the original stock mesa 12AX7s and it was perfectly fine. Then in the V2 position I started swapping in and out all my EH12AX7s to try to find the bad one(s). So I then started to notice that all of them had a certain hum, one of which was really bad. The only thing was all but one I believe hummed on the clean channel and then was whisper quiet on the high gain channel. It seemed like the clean channel was not liking the EH12AX7s all of a sudden. But no problems with the Mesa 12AX7s in either channel.

 

Any Ideas?

For now I'd get rid of the EH's.

 

Where did they come from?

 

Myles

[myles_rose]

Originally posted by johnny5:

Originally posted by myles111:

Originally posted by johnny5:

i have Reverend Hellhound combo (2 6L6's, 60W, 1X12) that has Electro Harmonics 6L6's in it. i have read that these tubes are not very good. and in listening i notice that when these suckers are pushed, they get less and less sweet. almost flabby. i was looking the groove tubes site at the CB's looks like i can get a little more power tube distortion out of those.

 

any thoughts or recomendations?

johnny5 ...

 

The CB's are Chinese with a softer vacuum, but do have more mids than the EH's .... most 6L6 tube actually do.

 

In your amp my favorite tube is the KT-66HP, that is also now one of the least expensive in the GT line as we dropped price from $85 a duet to $60.00 a duet ( $5.00 cheaper than the Chinese KT-66 we also carry with the price drop now ).

 

I like these with a #5 rating in your amp and in the Dr. Z Route 66 amp (that was designed around this particular tube if you check with them). I also use this in a JTM-45 and a GT Solo 45.

 

Myles

myles,

can i just directly replace the EH's with the KT's with out changing anything (considering the amp does not have a bias adjustment))?

 

thanks for the tip,

john

John,

 

You should still have the bias checked as the draw of a KT-66HP is different than that of a 6L6EH.

 

Let me know your B+ voltage and I will be happy to give you a mA range that if you are within, will be fine.

 

Myles

[El Glom-o]

Hi, Myles - When wiring a single speaker to an amp, is there a particular way the wires should be attached? What I mean is, does it matter which way the cone moves when the string is first put into motion by the pick or finger? Should the cone move forward as the string is being moved by the pick, or should the forward motion of the cone occur as the string snaps off of the pick? Or does it matter at all? Also, it would matter if one were using multiple amps, the cones should all be moving in the same direction at any one time, so is there a standard as to which speaker terminals the output wires attach to?

 

Thank you.

 

El Glom-o

[rsf1977]

So you think it's just bad tubes at this point and I got them from thetubestore.com

 

Oh and I forgot I had aNOS Mullard ECC83 in the V1 position which as I remember now when I switched it back to the EH12AX7 was at the same moment I switched to the GE6L6 could the mullard have screwed the rest of the tubes up some how?

 

Originally posted by myles111:

Originally posted by rsf1977:

ok when the buzzing originally started it was equal on both channels with all EH12AX7s in. Then I replaced them with the original stock mesa 12AX7s and it was perfectly fine. Then in the V2 position I started swapping in and out all my EH12AX7s to try to find the bad one(s). So I then started to notice that all of them had a certain hum, one of which was really bad. The only thing was all but one I believe hummed on the clean channel and then was whisper quiet on the high gain channel. It seemed like the clean channel was not liking the EH12AX7s all of a sudden. But no problems with the Mesa 12AX7s in either channel.

 

Any Ideas?

For now I'd get rid of the EH's.

 

Where did they come from?

 

Myles

[RoughDraft]

Hey Myles, thanks for taking the time to answer my questions. Could I just install a bias pot? What would the range have to be to change between these tubes? Would it just go in place of the bias resistor that is in there now?

 

Jon

[myles_rose]

Originally posted by tundrkys:

Hey Myles,, do you ever get tired of answering all these questions? I see we keep you pretty busy.

Just in case your answer is no(you don't ever get tired). I am sure you have answered this question many times before, but how do you know when it is time to change a tube? I ask this, because I have a Crate blueVoodoo 6212 combo. I bought it about eight years ago, because it had an awesome clean channel, and a helacious overdrive channel. I would say the clean sounded very Fender, and the dirty definitely had the hot rodded Marshall sound. Back then, it was almost unheard of to get that in one amp. Anyhow, I changed the output tubes on the thing about two years ago, and then the preamp tubes this year, and I just don't hear the Magic in the clean channel that it used to have. It was there before I changed the preamp tubes. Anyhow, now it is very Bright, and I can hear the attack on the strings, it is very painful at loud volumes. I was thinking about going back with the old tubes one by one, until I found one that I liked, but I keep thinking that if they were bad, they were bad, and I don't know if this will help. I don't know much about tubes, so going into a store and asking for a specific one seems kinda scary to me.

tundrkys...

 

I've been answering them for years, over two decades, but in the past it was in person, via mail and email, and phone. Now its also in this forum. Guess I am not sick of it yet

 

Your problem is pretty common. Your preamp tubes, when changed, probably had drastically different values than the replacements. Preamp tube are a crap shoot. Tubes of the same type, same vendor, same date code, all are different. They range from -50% below 1960's spec to +40%, with the vast range (80+% of them) below spec by at least 30%.

 

So .... say you had a tube in V1 that was putting out 1.1mA .... and now its replaced with a "new" tube ... that happens to be 0.7mA. Voila ... you are now down 37% on gain than the "old tube". The transconductance and rise time of the tube will also be very different. The life in the amp is gone.

 

What I do with my clients, before any work is started, is pull ALL their tubes and throw them on test equipment and tracing equipment. That is how we get a "baseline", and then in the future, we can go up or down on gain, compression and rise time. That's where the SAG came from (Special Applications Group) over at Groove Tubes. I had enough customers that required "graded tubes" that GT asked me to come to work for them in May, and start the SAG.

 

There is info on this on my personal website and on the GT website in the preamp tube area.

 

Myles

[myles_rose]

Originally posted by El Glom-o:

Hi, Myles - When wiring a single speaker to an amp, is there a particular way the wires should be attached? What I mean is, does it matter which way the cone moves when the string is first put into motion by the pick or finger? Should the cone move forward as the string is being moved by the pick, or should the forward motion of the cone occur as the string snaps off of the pick? Or does it matter at all? Also, it would matter if one were using multiple amps, the cones should all be moving in the same direction at any one time, so is there a standard as to which speaker terminals the output wires attach to?

 

Thank you.

 

El Glom-o

Yes, it does matter.

 

If two speakers are out of phase, there will be phase cancellation.

 

USA amps are generally set up where the string when hit produces forward speaker movement. Some Marshall amps are the opposite. In live applications I wire the amps (when different) to be in the same phase.

 

I wire the tip to + and the Sleeve to -

 

Myles

[myles_rose]

Originally posted by RoughDraft:

Hey Myles, thanks for taking the time to answer my questions. Could I just install a bias pot? What would the range have to be to change between these tubes? Would it just go in place of the bias resistor that is in there now?

 

Jon

Jon,

 

Installing a bias resistor that is adjustable is easy, fast, and cheap. I'd need to see the print to know what value is in there now, but you can probably just call the factory and ask their advice, as they probably do this as special order for a lot of their customers.

[steve f]

Myles,

 

I believe that you have commented on the fact that Marshall amps need to be biased a bit cold to retain the traditional Marshall tone.

 

I'm going to be biasing a friends JCM 600 (2 EL 34s) shortly. Since I don't know the plate voltage yet I'll just speak to the static dissipation figures. Normally I'd figure on approx 17.5 - 18.0 watts for EL34s. How much below that would you recommend for a Marshall?

 

I'm thinking of putting in either Svetlana EL34s or JJ E34Ls. I don't know if you have any recommendations as far as Svets vs JJs in master volume Marshalls, but feel free to state your preference if you have one. I'm just looking for good tone over the entire range, with tight bottom end.

 

Also I think you may have referred to the JJ E34Ls as being a higher powered tube. Would you suggest adjusting upward for this when biasing?

[dondottcomm]

Originally posted by myles111:

Originally posted by dondottcomm:

Hey Myles,I've got a 25/50 Jubilee Marshall 1/2 stack..And when Im playin the sound drops it gets real soft{volume} I know the chord is good ect. What is goin on with it..is it a pre tube or power tube or something like that??Thanks in advance!

dondottcomm,

 

First exchange V1 and some other tube, and see if that changes anything. If it does, it is a bad preamp tube. If not, try V2, etc.

 

This sounds more like a power tube problem though, how old are the output tubes?

 

Myles

Myles Thanks, it was a bad Pre tube..I changed all three out..Works perfect now..Just wanted to say thank you!

 

Don

[myles_rose]

Originally posted by steve f:

Myles,

 

I believe that you have commented on the fact that Marshall amps need to be biased a bit cold to retain the traditional Marshall tone.

 

I'm going to be biasing a friends JCM 600 (2 EL 34s) shortly. Since I don't know the plate voltage yet I'll just speak to the static dissipation figures. Normally I'd figure on approx 17.5 - 18.0 watts for EL34s. How much below that would you recommend for a Marshall?

 

I'm thinking of putting in either Svetlana EL34s or JJ E34Ls. I don't know if you have any recommendations as far as Svets vs JJs in master volume Marshalls, but feel free to state your preference if you have one. I'm just looking for good tone over the entire range, with tight bottom end.

 

Also I think you may have referred to the JJ E34Ls as being a higher powered tube. Would you suggest adjusting upward for this when biasing?

Steve,

 

Marshall's are a bit different in some regards to a lot of other amps as setting by idle dissapation does not always yield the best results. Typically I set up Marshall amps using a scope and a 1000 Hz signal, so when the amp is set to about "7", there is still a hint of crossover notch.

 

The EL-34's are 25 watt tubes, therefore using 50% ID as a guideline, we are talking 12 1/2 watts. As far as mA, with 450 B+ volts, this is about 28mA.

 

The E34LS is a 30 watt tube, and a lot stronger than the other EL-34's. It needs a different bias.... 33mA in the same example with the same B+ as above.

 

The Svetlana is the closest to the original Siemens tubes from the response curves of the currently made tubes, more linear than the LS, but not as strong .... boils down to personal preference I guess.

 

I like the Svets and the LS (JJ) for different reasons, but they are both very nice tubes. In my own Marshall amps I have used both, but being an old guy, I prefer the Svets a lot of the time as in a low range, I can get a 50 watt amp to breakup earlier and at a lower level. The LS's (JJ's) in a model 1987 will produce well over 70 watts in most Marshall 1987's, so the Svets in a rating of #3's for me, help quiet things down a bit .... but then again, most younger folks prefer the JJ's when you want to go for broke.

 

Myles

[myles_rose]

Originally posted by dondottcomm:

Originally posted by myles111:

Originally posted by dondottcomm:

Hey Myles,I've got a 25/50 Jubilee Marshall 1/2 stack..And when Im playin the sound drops it gets real soft{volume} I know the chord is good ect. What is goin on with it..is it a pre tube or power tube or something like that??Thanks in advance!

dondottcomm,

 

First exchange V1 and some other tube, and see if that changes anything. If it does, it is a bad preamp tube. If not, try V2, etc.

 

This sounds more like a power tube problem though, how old are the output tubes?

 

Myles

Myles Thanks, it was a bad Pre tube..I changed all three out..Works perfect now..Just wanted to say thank you!

 

Don

Don ... you are more than welcome....

 

Myles

[mikey_dup1]

Miles,

I am working with a Fender DeVille 410. I would like to get some more gain and smooth distortion. It hs quite a bit of harsh bark now. I've got a lot of headroom and this thing is so loud I rarely have enough space to open it up. I recently had Svetlana 6L6's put in and I mistakingly told them to match them for a lot of headroom. Had just got the amp. Can I offset it with some preamp tubes and if so what would they be (without breaking the bank). God Bless.

[myles_rose]

Originally posted by mikey:

Miles,

I am working with a Fender DeVille 410. I would like to get some more gain and smooth distortion. It hs quite a bit of harsh bark now. I've got a lot of headroom and this thing is so loud I rarely have enough space to open it up. I recently had Svetlana 6L6's put in and I mistakingly told them to match them for a lot of headroom. Had just got the amp. Can I offset it with some preamp tubes and if so what would they be (without breaking the bank). God Bless.

Mikey,

 

The first thing you may want to try is a 12AX7C in your V1 position. These are a bit warmer and darker than the probable Sovtek 12AX7WA that is stock in these amps.

 

There are a lot of folks that have these ... and most any guitar store that has tubes should have these in stock.

 

If you are not concerned about the random nature of preamp tubes, any "new tooling" 12AX7C will be fine. You can get those from a number of folks on my website from the links below on my website.

 

Info on the GT 12AX7C is at:

http://www.groovetubes.com/product.cfm?Product_ID=1158

 

If you want a 12AX7C with a specific character and rise time, then it's going to cost a lot more for a curve traced tube.

 

Info on this tube is at:

http://www.groovetubes.com/product.cfm?Product_ID=1730 but these are not stocked items, they are specifically made per request.

 

For a start though, you should be able to get a decent 12AX7C for under $15 at the most.

 

Myles

[Oscar]

Myles,

 

I have a '98 HotRod DeLuxe. When playing on the clean channel, on certain chords and notes a glassy, rattling sound comes out of the amp that's very annoying. This does not occur on the overdrive channels. It really sounds as if a small part in a tube is rattling, so I replaced the preamp tubes one-at-a-time with a NOS '60's Telefunken 12AX7 but the problem remained. I turned up the amp with no guitar connected and softly tapped the 6L6's with the back of a pencil - no weird noises. This leads me to conclude that the tubes are OK. I also disconnected the reverb tank - the problem persisted. I can't think of anything else to do. Do you have any suggestions? Thanks!

 

Regards,

Oscar

[Jamesian]

Myles, I have a mid-80's 60 watt Boogie Mk III head run through a Marshall cab. It is an absolute tone-machine for recording and I have no complaints, but I would like to expand its range if possible. I'm looking for: 1. that warm,early Fender,soft-attack tone (in the clean channel). 2. more of a British voice (Vox/Hi-Watt). Is there any kind of tube swap that will give me either of these changes in tone and response? Thanks. J.

[myles_rose]

Originally posted by Oscar:

Myles,

 

I have a '98 HotRod DeLuxe. When playing on the clean channel, on certain chords and notes a glassy, rattling sound comes out of the amp that's very annoying. This does not occur on the overdrive channels. It really sounds as if a small part in a tube is rattling, so I replaced the preamp tubes one-at-a-time with a NOS '60's Telefunken 12AX7 but the problem remained. I turned up the amp with no guitar connected and softly tapped the 6L6's with the back of a pencil - no weird noises. This leads me to conclude that the tubes are OK. I also disconnected the reverb tank - the problem persisted. I can't think of anything else to do. Do you have any suggestions? Thanks!

 

Regards,

Oscar

Oscar,

 

I wish I could get the amp on a scope. You have done all the normal things.

 

The issue with the Hot Rod Deluxe/Deville series, is the ribbon interconnects and the design of the overdrive circuit and reverb drive circuit are all solid state generated. There are a few tuning tricks to getting rid of the interactions that come up, but I'd need to get the amp on the bench.

 

Sorry ....

 

Myles

[myles_rose]

Originally posted by Jamesian:

Myles, I have a mid-80's 60 watt Boogie Mk III head run through a Marshall cab. It is an absolute tone-machine for recording and I have no complaints, but I would like to expand its range if possible. I'm looking for: 1. that warm,early Fender,soft-attack tone (in the clean channel). 2. more of a British voice (Vox/Hi-Watt). Is there any kind of tube swap that will give me either of these changes in tone and response? Thanks. J.

J...

 

This is a real common request. My personal buisness clients had me make kits up for them for years, so when I came to GT in May of this year, part of what was on my list was to do the same thing here. I finally got around to it:

 

http://www.groovetubes.com/product.cfm?Product_ID=1768

 

Myles

[johnny5]

Originally posted by myles111:

Originally posted by RoughDraft:

Hey Myles, thanks for taking the time to answer my questions. Could I just install a bias pot? What would the range have to be to change between these tubes? Would it just go in place of the bias resistor that is in there now?

 

Jon

Jon,

 

Installing a bias resistor that is adjustable is easy, fast, and cheap. I'd need to see the print to know what value is in there now, but you can probably just call the factory and ask their advice, as they probably do this as special order for a lot of their customers.

Jon and/or myles,

i also have the hellhound and am curious in your results / sounds. would be neat to be able to use 6L6's OR EL34's though!

 

let us know!

[myles_rose]

Originally posted by johnny5:

Originally posted by myles111:

Originally posted by RoughDraft:

Hey Myles, thanks for taking the time to answer my questions. Could I just install a bias pot? What would the range have to be to change between these tubes? Would it just go in place of the bias resistor that is in there now?

 

Jon

Jon,

 

Installing a bias resistor that is adjustable is easy, fast, and cheap. I'd need to see the print to know what value is in there now, but you can probably just call the factory and ask their advice, as they probably do this as special order for a lot of their customers.

Jon and/or myles,

i also have the hellhound and am curious in your results / sounds. would be neat to be able to use 6L6's OR EL34's though!

 

let us know!

Jon,

 

You can also modify the bias circuit with a switch and resistor network to all the use of 6L6's or EL-34's as some amps do, but I'd rather use a wider range adjustable system than a switch, as 6L6's are very different in bias (from about -49 volts to - 62 volts .... and a lot of older Fender's were factory set at -52 as a matter of info I guess for you folks), which can be way far from optimum.

 

In the case of EL-34's, it can range from about -45 to -50, and with 6550's -63 to -68 or so (which is why the 70's Marshalls initially shipped with 6550's didn't even have the bias adjusted, so they were way off, and that is why people said "the old Marshalls were better than the new ones" back then, when in actuality, they were made a bit better. Once the USA Marshalls that were shipped with 6550's that were correctly biased, they were a lot better sounding than the 6550 versions with the wrong bias.

 

If you look at an E34Ls and a 6L6S, the bias is very close. The 6L6S is more of a EL-34 than a 6L6 when it comes to bias, and has a sound to me that is half way between an EL-34 and 6L6. Its a great tube in Mesa amps for me.

 

The best bet is always to be able to properly adjust an amp for top performance. The ones that are not done that way are the vintage amps that sound good, but don't have "the magic" that some amps have that folks just figure they are just one of the rare examples.

 

If you look at the +/- 20% parts, and get those closer, look at transformers, tubes, voltages, etc., any amp that has the magic can have its settings applied to any amp in the same type and model, and greatly improve the "average" amp.

 

Myles

[myles_rose]

Bumping for new forum folks