Feel free to ask Myles

[garyrogue]

Thanks Myles,

May be awhile before before this stock of tubes is burned up, but I'll be going the GT rated ones as replacements. So those Siemens should be able to be dropped into the 6545 head without a rebias?

 

Forgot to mention I have two used Mullard EF-86's I place in the head.

 

Can not believe how the Maz-18 2x10 combo sounds through the Zbest 2x12 cabinet (which I just got) when plugged into it. The vol and tone, it is like there are no vol chokes/governers on his amps.

Thank again, have a good weekend.

[myles_rose]

Originally posted by garyrogue:

Thanks Myles,

May be awhile before before this stock of tubes is burned up, but I'll be going the GT rated ones as replacements. So those Siemens should be able to be dropped into the 6545 head without a rebias?

 

Forgot to mention I have two used Mullard EF-86's I place in the head.

 

Can not believe how the Maz-18 2x10 combo sounds through the Zbest 2x12 cabinet (which I just got) when plugged into it. The vol and tone, it is like there are no vol chokes/governers on his amps.

Thank again, have a good weekend.

garyrogue ....

 

The Siemens can "probably" be dropped right in, but if they are high current draw tubes, you may have too high of a current draw. You might want to keep an eye on them, in the dark, after 10 minutes or so, just to make sure the plates are not glowing.

 

The Mullard EF-86's are terrific. These will need to be replaced, if you play about three hours each day, in about 6-10 years A new EF-86 will go about the same amount of time ... but in MONTHS, not YEARS.... but ... chances are, the new one will become microphonic long before it wears out! If the new ones meet spec (which 95% of them do not), then you will be fine with a new one. Not too many folks test them closely enough though to know.

 

EF86's should be tested at 250 volts on the plates, 140 volts in the screen, a -2 volt bias and in PENTODE mode, and show 3mA of output (NOT 4mA+ as most new tubes ... these are very noisy) and have a Transconductance of 2000 .... not 3000+ as most new ones.

 

So, there is a bit of info for your tube vendor.

 

The Dr Z. amps rated at 18 watts are just silly. If they are 18 watt amps, then my Marshall JTM-45 must be a 10 watt amp in comparison. The 18 watt Z's are a LOT louder than my amp, even through the same cabs and speakers.

 

You have a great weekend too

[garyrogue]

Thanks, I'll let know how the measurment turns out. Tube tester is at work and we just have to be unbusy at same time to do tests.

Gary

[teleboy 59]

Hi Myles, I have enjoyed reading some of your comments,very helpful.

I was wondering if you could help me.I have a mesa boogie nomad 100 and am contemplating putting some NOS tubes that I own in it,actually I already tryed it out for a few minutes.The tubes are Jan Phillips WGB.Hopefully I didn't do any damage.A tech that I know told me it would probably be okay so I tried it.Any help or answers you may have would be helpful.The reason I am asking is another tech I know told me I was playing russian roulette.

[myles_rose]

Originally posted by garyrogue:

Thanks, I'll let know how the measurment turns out. Tube tester is at work and we just have to be unbusy at same time to do tests.

Gary

Gary,

 

Let me know what "numbers" you come up with and perhaps I can make some sort of conversion scale if I send you a "known" value tube and then you see what your tester says with that one.

[myles_rose]

Originally posted by teleboy 59:

Hi Myles, I have enjoyed reading some of your comments,very helpful.

I was wondering if you could help me.I have a mesa boogie nomad 100 and am contemplating putting some NOS tubes that I own in it,actually I already tryed it out for a few minutes.The tubes are Jan Phillips WGB.Hopefully I didn't do any damage.A tech that I know told me it would probably be okay so I tried it.Any help or answers you may have would be helpful.The reason I am asking is another tech I know told me I was playing russian roulette.

teleboy 59 ....

 

I will more than happy to try to help you.

 

First of all, the JAN Philips WGB's are great tubes for your amp (especially in V1 and V2), and if you took them out ... PUT THEM BACK ... as they are MUCH better than the stock tubes. You did not, or will not cause any damage. There is no adjustment at all required ... you can swap these in and out at will or whim.

 

If a tech says you are playing russian roulette doing this, I would have to venture two or so guesses ....

 

1. He wants to do it and charge you.

 

2. He is not a bright tech, and I would suggest you find a new one.

 

There are a lot of folks these days that call themselves amp techs that learned most of what they know via trial and error, not by any sort of understanding or education in electronics or electronic design.

 

I recently had a letter to me at GT, where I had recommened a tube for V1, and the person wrote me back saying his "tech" needed to know what "V1" meant. I also suggested a "new tech" for him.

 

I am not trying to ruin anybodies business here, or attack their credentials, but my first job here is to give true data and advice, and if there are folks out there taking advantage of "MY" forum folks, I take offense to that.

 

I apologize if any amp techs out there take offense to this, but the good ones know what I mean and would benefit with more business and less messy cleanup from the bad ones out there.

[teleboy 59]

Hi Myles,

Thank you so much for responding so quickly and so informative to.I am sorry I wasn't perfectly clear in my last reply.These tubes are output tubes, 6L6's to be exact, does this make any difference.Thank you so much for the advice

[myles_rose]

Originally posted by teleboy 59:

Hi Myles,

Thank you so much for responding so quickly and so informative to.I am sorry I wasn't perfectly clear in my last reply.These tubes are output tubes, 6L6's to be exact, does this make any difference.Thank you so much for the advice

teleboy 59 ....

 

There are a lot of different 6L6's and anytime output tubes are changed, it is best to have the bias checked and adjusted.

 

If you have something "known" such as "white" Fender 6L6's, then you can replace them with "white" Fender 6L6's without the need to rebias, but, if you change tube type or change tubes, even within the same type, maker, and brand, you should have your bias checked.

[JonObi]

Hi Myles,

 

I am looking to re-valve my Marshall JCM900 4100 (Hi-gain Dual Reverb)head, used with a Marshall 1960A cab. It still has the stock tubes in it and, while i'm not unhappy with it's sound, i'd like to try and improve it.

 

I have very little knowledge of tubes and have been looking at your site + read many of your informative posts on the Harmony Central website,and i was hoping you could offer some advice.

 

Basically, I would like slightly more gain (i.e - modern rock), yet I want some amount of versatility as I also play Jazz and Blues, so a good,deep clean sound would be nice. I appreciate it's impossible to cover all bases, so please forgive me if what i'm saying is totally unrealistic. I find that the JCM as it is can be versatile, just a little too...well..."Marshall-like" :-). Doh!! I liked it when I got it.

 

Anyway, could you recommend a pre-amp and power-amp tube combination that will come closest to my requirements. I've been looking at the

Electro-Harmonix 12ax7's and have read good things about them, and alos the EH EL-34's. My only reservation with these is will they provide enough gain?

 

Thanks very much for your time and assistance. I look forward to hearing your reply.

[Franknputer]

By the way - sorry, Miles, but...

 

let's play bump the XXXXX...

[Brakka]

...

[not coaster MODERATOR]

Keep this thread on page 1.

[michael saulnier]

Originally posted by Cereal - friend of Thanksgiving:

Keep this thread on page 1.

And bless us, every one.

 

guitplayer

[mark_dog]

boomp

[Anifa]

[myles_rose]

Originally posted by JonObi:

Hi Myles,

 

I am looking to re-valve my Marshall JCM900 4100 (Hi-gain Dual Reverb)head, used with a Marshall 1960A cab. It still has the stock tubes in it and, while i'm not unhappy with it's sound, i'd like to try and improve it.

 

I have very little knowledge of tubes and have been looking at your site + read many of your informative posts on the Harmony Central website,and i was hoping you could offer some advice.

 

Basically, I would like slightly more gain (i.e - modern rock), yet I want some amount of versatility as I also play Jazz and Blues, so a good,deep clean sound would be nice. I appreciate it's impossible to cover all bases, so please forgive me if what i'm saying is totally unrealistic. I find that the JCM as it is can be versatile, just a little too...well..."Marshall-like" :-). Doh!! I liked it when I got it.

 

Anyway, could you recommend a pre-amp and power-amp tube combination that will come closest to my requirements. I've been looking at the

Electro-Harmonix 12ax7's and have read good things about them, and alos the EH EL-34's. My only reservation with these is will they provide enough gain?

 

Thanks very much for your time and assistance. I look forward to hearing your reply.

JonObi....

 

For more gain and a more agressive nature in these amps, I use a high gain selected ECC83 in V1 and V2. These have a lot more output than the stock tubes.

 

GT has them in kits in the SAG (Special Applications Group), but not a lot of them, actually, at this moment, three kits (they stay in my desk).

 

http://www.groovetubes.com/product.cfm?Product_ID=1737

 

The problem is, for Jazz and Blues, these will be too noisy, and too much front end gain and not the right ratio of power amp section gain.

 

For that sort of sound, I use in V1, a 12AX7C9.

 

To cover "more" bases, but not all, most of my clients have what is called a TT kit. This has a selected ECC83 for the "Brit" stuff, a 7025 for the "brite" stuff (60's rock), and a 12AX7C for overall stuff ... 60's, 70's, jazz and blues. Depending on the need, V1 is swapped.

 

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

 

I also make up specific tube for specific applications:

 

http://www.groovetubes.com/product.cfm?Product_ID=1773

 

The 12AX7EH is a good tube, and perhaps the most consistant of any of the current Russian offerings.

 

The EH EL-34 is close in curves to the old Siemens, but most of my clients prefer the new tooling Chinese EL-34's. These are sold under the Ruby Tubes name, as they developed this tooling. I reviewed these tubes not too long ago:

 

http://www.guitaramplifierblueprinting.com/el34.html

 

On that page, ignore the old data on Chinese tubes. This is older stuff that Watford has not gotten around to updating. The new Chinese tubes are stronger than the Russian tubes and handle modern amp B+ voltages very well now.

 

The Chinese EL-34's are available in a straight bottle and a slightly larger bottle. Both trace about the same, both better (or at least more linear and consistant than the current Russian tubes).

 

I use the EL-34C in a LOT of clients amps.

 

The EL-34's that are NOT the E34Ls, are more in line with the original Marshall sound. The E34Ls is more agressive with more pronounced mids and lows. It is also a 30 watt tube, not a 25 watter as all other EL-34's.

 

Hope this was of some help.

[JonObi]

Thanks for the help Myles.

I will look in to the Ruby Tubes and the ECC 83's.

 

Do you know any good uk stockists for groove tubes or ruby tubes?

 

Once again, thanks very much for your help Myles - much appreciated.

[myles_rose]

Originally posted by JonObi:

Thanks for the help Myles.

I will look in to the Ruby Tubes and the ECC 83's.

 

Do you know any good uk stockists for groove tubes or ruby tubes?

 

Once again, thanks very much for your help Myles - much appreciated.

JonObi ....

 

In the UK ....

 

Groove Tubes Europe c/o Guitar XS Ltd. - Doug Chandler or Tina Shapre

Thomas Point 12a Waterside

Upper Brents, Faversham, Kent, ME13 7AU

Kent, Email: Doug@guitarXS.com

Phone: +44 (0)1795 538877

Fax: +44 (0)1795 538877

 

Hope that is of help ....

[JonObi]

Thats great Myles, thanks very much. Again, your help has been very useful. Cheers.

[Edward]

Hey Myles,

I recently ordered a hand wired single-ended Class A 8 watt combo [built by Rob of Fab Enterprises of Vancover Canada].The amp has two pre-amps stages [high gain early Plexi and clean Tweed] with seperate tone stacks.Also,each channel has it's own gain control.The 8 watt power section runs a single 6L6 tube and has the master volume and bright switch.Mine will have a single Celestion G12H-30 and a tube buffered series fx loop.My question to you is what power tube [be it NOS,Eastern Euro,6L6,5881,etc...] would you recommend.I play mostly modern blues,classic rock and some jazz and really like that touch dynamic,"in-between" tone of a tube amp on the verge of going into overdrive.The pre-amp tubes are all NOS,but the stock 6L6 is a generic Sovtek.Of course the stock tube might sound quite good but,like the Class A THD UniValve,tubes of higher quality would probably bring out the best in what looks to be a killer little Class A combo.Thanks Myles,for any help or advice that you can give.

Ed

[myles_rose]

Originally posted by Edward:

Hey Myles,

I recently ordered a hand wired single-ended Class A 8 watt combo [built by Rob of Fab Enterprises of Vancover Canada].The amp has two pre-amps stages [high gain early Plexi and clean Tweed] with seperate tone stacks.Also,each channel has it's own gain control.The 8 watt power section runs a single 6L6 tube and has the master volume and bright switch.Mine will have a single Celestion G12H-30 and a tube buffered series fx loop.My question to you is what power tube [be it NOS,Eastern Euro,6L6,5881,etc...] would you recommend.I play mostly modern blues,classic rock and some jazz and really like that touch dynamic,"in-between" tone of a tube amp on the verge of going into overdrive.The pre-amp tubes are all NOS,but the stock 6L6 is a generic Sovtek.Of course the stock tube might sound quite good but,like the Class A THD UniValve,tubes of higher quality would probably bring out the best in what looks to be a killer little Class A combo.Thanks Myles,for any help or advice that you can give.

Ed

Ed ....

 

First off ... good luck in getting this amp in a fast timeframe. These are now the deal of the century, even the last century. Rob up there and I have talked. I could not figure out how he could sell his amps for this price, as his BOM (bill of materials) would exceed the cost of the amp! He explained he is selling them at a loss to gain a reputation faster ....

 

I guess when you have a great product and give it away, that will build a rep faster as you have more amps out there.

 

On the 6L6, his amps are very articulate due to proper design and a non "garbage" front end. I'd have a few 6L6's for this amp .... a NOS GE or the newer USA GE from Groove Tubes (these are sold in single tube qualtities), a KT-66 for sure, and an NOS Tung Sol 5881 (try Mike at www.kcanostubes.com). These will all sound different.

 

The KT-66 IS THE KILLER blues tube. I have written a bit on what "KT" meant, and that is why these are so linear and huge sounding. They are also an amazing rock and jazz tube. I probably prefer these in Fenders most of the time these days when not using the GE's. I personally, for my taste, prefer them to the GE's. If you want one of these at a great cost, one fellow that supplies a lot of my clients is Doug Preston. He can be contacted at: djp@optonline.net

 

The stock Sovtek can be improved upon with virtually any tube in most cases. They are reliable and nice sounding, and inexpensive, but for what Rob is charging for these amps, I am surprised he puts any tubes in them at all!

 

Hope this helped.

[Edward]

Thanks Myles!As usual,you are a virtual fountain of knowledge and information.The options,ideas and explanations for each have given me very much and are most appreciated.BTW,thanks for giving me a couple of more reasons for feeling positive about my CM8 purchase.Myles...you are the best!

Cheers,Ed.

[myles_rose]

Originally posted by Edward:

Thanks Myles!As usual,you are a virtual fountain of knowledge and information.The options,ideas and explanations for each have given me very much and are most appreciated.BTW,thanks for giving me a couple of more reasons for feeling positive about my CM8 purchase.Myles...you are the best!

Cheers,Ed.

Ed ...

 

You are more than welcome. As my wife puts it ... I am a "vast storehouse of useless information".

 

As far as your CM8, Rob does super work, and you are basically getting the amp for just about nothing, or in the real world, about a 85% discount over what an average amp like this would sell for at retail levels, but these are anything but average amps.

 

I think you are going to be very happy. Write a review when you get it!

[Edward]

Will do,Myles and thanks again.BTW,what is the going price on the new USA GE 6L6 from Groove Tubes?

Ed

[myles_rose]

Originally posted by Edward:

Will do,Myles and thanks again.BTW,what is the going price on the new USA GE 6L6 from Groove Tubes?

Ed

Ed,

 

They are $90 a duet retail, and $180 a quad retail. Yup ... not cheap, but that is what happens with USA materials and labor, and the materials are very high.

 

Most dealers do discount though, so that may be of help.

 

The prices and some photos (badly taken by me ... sorry ....) are at the bottom of each of the 6L6GE pages:

 

http://www.groovetubes.com/product.cfm?Product_ID=1713

[johnny5]

myles,

quick and easy;

can you switch preamp tubes while a tube amp is on? maybe if both gain and volume controls are all the way down?

 

curious to see if i have to power on and off when going through preamp tubes to fine tune my sound.

 

john

[myles_rose]

Originally posted by johnny5:

myles,

quick and easy;

can you switch preamp tubes while a tube amp is on? maybe if both gain and volume controls are all the way down?

 

curious to see if i have to power on and off when going through preamp tubes to fine tune my sound.

 

john

John,

 

You bet ... just remember, they can get warm. Don't try this with power tubes though.

 

Make sure the volumes are all the way down, as there is going to be a big POP when you pull preamp tubes, and you don't want to stress a speaker.

 

We do this all the time with the tripple tone kits for V1.

[johnny5]

thank you!

 

Originally posted by myles111:

Originally posted by johnny5:

myles,

quick and easy;

can you switch preamp tubes while a tube amp is on? maybe if both gain and volume controls are all the way down?

 

curious to see if i have to power on and off when going through preamp tubes to fine tune my sound.

 

john

John,

 

You bet ... just remember, they can get warm. Don't try this with power tubes though.

 

Make sure the volumes are all the way down, as there is going to be a big POP when you pull preamp tubes, and you don't want to stress a speaker.

 

We do this all the time with the tripple tone kits for V1.

[myles_rose]

Originally posted by johnny5:

thank you!

 

Originally posted by myles111:

Originally posted by johnny5:

myles,

quick and easy;

can you switch preamp tubes while a tube amp is on? maybe if both gain and volume controls are all the way down?

 

curious to see if i have to power on and off when going through preamp tubes to fine tune my sound.

 

john

John,

 

You bet ... just remember, they can get warm. Don't try this with power tubes though.

 

Make sure the volumes are all the way down, as there is going to be a big POP when you pull preamp tubes, and you don't want to stress a speaker.

 

We do this all the time with the tripple tone kits for V1.

.... you are more than welcome

[dave251]

Just unpacked the new Fender Pro Junior a while ago...I was bummed...sounded like a motorboat. I tried swapping places with the two 12AX7's...made it worse. Hmmmm. Pulled out the "bad" one, moved the other back to the preamp, and put a 12AT7 in the splitter hole....MUCH better, more quiet, although not as quiet as it should be...so it's going back. They'll ship me another.

 

These tubes are labelled "GT" by the way...

 

Even with all the noise, I like this little amp. Should be just the right thing for the neighborhood jam. Hopefully the next one they send will be a bit quieter....

 

BTW, one of our regulars here at the B&B is bringing me several boxes full of NOS tubes. I'll be going through them....most of them will be from the 50's and 60's, as his dad shut down the radio/tv repair about 1970...been hiding all these years. He's supposed to be sending me a list...so I'll let you all know what we've got.