Welcome to the MacNN Forums.

RAILhead · Jul 11, 2006, 02:27 PM

First off, I've been playing the guitar for about 23 years, mostly solid state, until I got my Carvin and Traynor tube amps. I sold the Carvin and now I have a small Traynor Custom Valve 20 tube amp — but since I've never really messed with the tubes in any of my amps, I have some questions. My Traynor has 2 12AX7 preamp tubes in V1 and V2), 1 12AX7 phase splitter in V3, and 2 6BQ5s in V4 and V5.

Here are my "dumb" questions...

1) If I want to play around with tweaking my sound (to get brighter tone, etc.), which tubes should I change? My understanding is that I need to play with the preamp tubes (and change the phase splitter at the same time). Is this correct?

2) Do I have to use "12AX7" tubes, or will others, like ECC83s work?

3) Can my 6BQ5s be replaces with 5881s?

4) As for pre and power tube replacement, how do I know what will work in my amp?

Thanks!

ratter · Jul 11, 2006, 02:41 PM

1. V1 will likely have the most drastic tonal effect. You can try different brands of 12AX7/ECC83's in there.

2. 12AX7 and ECC83's are two different names for the same kind of tube.

3. I believe 6BQ5's are interchangeable with EL84's, not 5881's.

4. For the preamp (V1, V2, and V3), you can pop any kind of 12AX7 in there. Just power down and swap them out, nothing more needs to be done. There are also some interchangeable types like 12AY7 or 12AU7's that will also work in there. For the power tubes (V4 and V5), you may be able to swap them on the fly without doing any extra work, OR your amp may require a rebias (adjusting the bias current going to the tubes), which is something you would probably want to leave to a tech. I'm not familiar with your particular amp but a quick net search should turn up that information for you, or a call to the company's customer service.

Also, any good tube vendor should be able to make recommendations and sell you tubes that will work in your amp.

http://www.dougstubes.com/
http://www.kcanostubes.com/

Those are two reputable dealers that you can start with.

Kevin · Jul 11, 2006, 02:46 PM

bias is important!! Get it done right. Or you'll hate your sound.

olePigeon · Jul 11, 2006, 02:57 PM

I suggest switching to a gazoo.

ratter · Jul 11, 2006, 03:15 PM

Just checked on your particular Traynor. Like most EL84 amps, it's cathode-biased. What that means is, you can replace the power tubes without rebiasing. Buy a matched set of EL84/6BQ5's, pop them in, and you're done. Changing power tubes likely won't have as large of a tonal effect as changing V1 and then V2, though.

RAILhead · Jul 11, 2006, 03:18 PM

My amp has auto-bias capability. Don't know how good it works, but it's advertised as being able to handle different brads, etc., without needing to be reset. You also don't have to buy matched pairs (supposedly).

RAILhead · Jul 11, 2006, 03:19 PM

Heh, beat me to it.

Thanks for the info so far!

analogika · Jul 11, 2006, 03:56 PM

Tube substitution key: http://www.project.llaky.fi/audiocre...ge/tuberef.htm

Tube lettering codes: http://www.project.llaky.fi/audiocre...ge/tubekey.htm

RAILhead · Jul 11, 2006, 04:15 PM

Thanks for the links and info. Now I just need to find out what brand Marshall used in 1959...

Doofy · Jul 11, 2006, 05:05 PM

Originally Posted by RAILhead

Thanks for the links and info. Now I just need to find out what brand Marshall used in 1959...

I was unaware that Marshall existed in 1959.

If you mean the 1959 model, ask 'em what they're using in the current 1959HW, since they're supposed to be identical to the original.

BTW, I love it when folks embark on their quest to find "the tone".

RAILhead · Jul 11, 2006, 05:50 PM

Yeah, that's what I meant.

And yes, I'm planning on trying several different tubes until I get a combo I totally love (once I get the amp fixed).

Doofy · Jul 11, 2006, 06:05 PM

BTW, have you seen what Randall are doing with their MTS series?

http://www.randallamplifiers.com/pro.../mts/index.asp

I really like that idea. Sort of like the old Seymour Duncan Convertible range.

RAILhead · Jul 11, 2006, 06:31 PM

Yeah, that's pretty freaking sweet!

RAILhead · Jul 12, 2006, 10:40 AM

I just shipped it off. It ought to arrive on Tuesday, and they said their turnaround is just 1 to 2 weeks.

In the mean time, I'm starting my collection of tube replacement stock with the following:

V1 and V2: Hi-Gain Sovtek 12AX7LPS
V3: Electro-Harmonix 12AX7EH with balanced triodes (my phase splitter)
V4 and V5: Ei EL84 Elite

I found a place that still had some original Mullard power tubes, but they wanted $99 for ONE. Anyway, this is my first set of test tubes (pun intended) once I get my amp back.

kobi · Jul 12, 2006, 11:10 AM

Railhead,
Try Groove Tubes for the El84's. They have a distortion rating system with there tubes. The higher the rating the less distorted the tubes will get.

With that you can "tailor" the amount of distortion that your getting from the power amp section.

BTW those Traynor amps are great. I have a Bass Mate 1x12 15 watt EL84 combo and a YBA-1A Bass Master 50 watt that I put KT-88's in. They are great amps, basically handwired copys of Fender. Marshall and Vox's. Great guitar amps.

Where did you ship your amp to do get the work done? What city do you live in? I used to do the guitar show circuit, I might know of a local guy for tube work depending on where you live.

RAILhead · Jul 12, 2006, 11:41 AM

I sent it back to Yorkville, which is in Niagra Falls NY. And yeah, I totally LOVE my little CV20. It's a mere 15 watts, but it sounds superb in all situations — plus all the onboard controls, etc.

I'm in South Texas and I called all the places Yorkville lists on their site, but none service them any longer for some reason.

I'll check into Groove Tubes again, too.