Valves

[TelePaul]

Are all valve series interchangeable? Like if I want a new ECC83 for my Marshall AVT can I buy any va;ve that says ECC83 or does it vary between manufacturer?

[mrface2112]

an ecc83 = ecc83 = ecc83 in terms of pinouts and 'compatibility'.

by all means YES try different valves from different manufacturers. new/different valves are about the easiest and cheapest mod/change you can make to an amp and can often be quite dramatic in sound.


cheers,
wade

[TelePaul]

Originally Posted by mrface2112

an ecc83 = ecc83 = ecc83 in terms of pinouts and 'compatibility'.

by all means YES try different valves from different manufacturers. new/different valves are about the easiest and cheapest mod/change you can make to an amp and can often be quite dramatic in sound.


cheers,
wade

Oh right okay, but in terms of...I dunno, volts and stuff like that they're all switchable?

[ocnor]

Yes they are all 12AX7 type tubes which are 12 volt and use the same pinout. A JJ/Tesla ECC83 would be a good choice for your amp.

[TelePaul]

Thanks OCNOR I'm not even sure if this will solve my problem...I've a marshall AVT 50, it just ahs the one valve.

[ocnor]

What problem are you having?

[mrface2112]

Originally Posted by ocnor

A JJ/Tesla ECC83 would be a good choice for your amp.

+1 for the JJ/Tesla. I refitted my silverface champ and my epi VJ with JJ's from eurotubes and they really sing now. MUCH nicer than the ElectroHarmonix and Sovteks that were in there, respectively.


cheers,
wade

[TelePaul]

Originally Posted by ocnor

What problem are you having?

A ringing undertone, like somethign is rattling inside the amp....but I opened her up and checked thoroughly.

[ocnor]

That could be the tube. Does it rattle on the clean channel as well as the distortion channel?

[TelePaul]

Originally Posted by ocnor

That could be the tube. Does it rattle on the clean channel as well as the distortion channel?

It seems to be rattling only on the clean; hoenstly, I can't hear it under the distortion. It's annoying, but only seems to happen on certain notes. I might open up the reverb tank tomorrow. It's the only thing - along with fitting a new valve - that I have yet to check.

[boingoman]

Originally Posted by TelePaul

It seems to be rattling only on the clean; hoenstly, I can't hear it under the distortion. It's annoying, but only seems to happen on certain notes. I might open up the reverb tank tomorrow. It's the only thing - along with fitting a new valve - that I have yet to check.

In anything that has tubes in it, the tube is always pretty much the first thing you check. Quick test- with the amp on and volume up, rap the tube with a pencil or something. You'll be able to tell if it's microphonic.

[Track Rat]

You might have microphonic tube. But as far as cross referencing tubes, this is VERY handy.
http://www.nj7p.org/Tube.php

[TelePaul]

Originally Posted by boingoman

In anything that has tubes in it, the tube is always pretty much the first thing you check. Quick test- with the amp on and volume up, rap the tube with a pencil or something. You'll be able to tell if it's microphonic.

Oh, clever, I'll check that tomorrow. Thanks everyone.

[TelePaul]

Originally Posted by boingoman

In anything that has tubes in it, the tube is always pretty much the first thing you check. Quick test- with the amp on and volume up, rap the tube with a pencil or something. You'll be able to tell if it's microphonic.

Should I play as well, no?

[ocnor]

Originally Posted by TelePaul

It seems to be rattling only on the clean; hoenstly, I can't hear it under the distortion. It's annoying, but only seems to happen on certain notes. I might open up the reverb tank tomorrow. It's the only thing - along with fitting a new valve - that I have yet to check.

That sounds more like a problem with the speaker. It could be that the speaker can't handle the lows at the volume that you are playing. You might need to use a compressor pedal in front of the amp.

[TelePaul]

Originally Posted by ocnor

That sounds more like a problem with the speaker. It could be that the speaker can't handle the lows at the volume that you are playing. You might need to use a compressor pedal in front of the amp.

I don't think it's the speaker, I'll try it with a compressor and see what happens.

[TelePaul]

Originally Posted by mrface2112

+1 for the JJ/Tesla. I refitted my silverface champ and my epi VJ with JJ's from eurotubes and they really sing now. MUCH nicer than the ElectroHarmonix and Sovteks that were in there, respectively.


cheers,
wade

Where does one get a JJ/Telsa Wade? I'm gonna try the valve even to rule it out as a possibility. Failing that, I'm gonna ring a local guy that fixes amps and see what he thinks.

[Track Rat]

http://www.tubedepot.com/

[TelePaul]

Originally Posted by Track Rat

http://www.tubedepot.com/

Wow thanks Mike! I was wondering about the 'tetsing', what tests should I have done? Also, if anyone's interested I sent an e-mail to Marshall tech support and got an e mail back today. I think they have representatives in different country, because the guy that got back to me - saying he was forwarding my request to an engineer - works in the music store in town. Small world, I was surprised by the good service though.

[Outlaws]

Originally Posted by TelePaul

A ringing undertone, like somethign is rattling inside the amp....but I opened her up and checked thoroughly.

95% of the time that will be a bad tube.

[TelePaul]

Originally Posted by Outlaws

95% of the time that will be a bad tube.

Yeah, I've been hearing this quite alot now, so I'm definetely ordering a JJTesla, even to rule the tube out as the problem. Thanks!

[mrface2112]

Originally Posted by TelePaul

Where does one get a JJ/Telsa Wade?

I got mine from www.eurotubes.com. Great service, fast delivery, good prices and excellent tubes. All around good folks and I will definitely be ordering from them again.

I ordered a "regular gain" 12ax7 for my Champ and one of the "high gain" 12ax7's for my Epi VJ. there's definitely a difference in sound between the two and the "high gain" definitely has more bite and is a good fit for the VJ.

I can't vouch for the site that Mike posted, but if he's posting it, I'm sure they're good folks too.


cheers,
wade

[Outlaws]

Originally Posted by TelePaul

Yeah, I've been hearing this quite alot now, so I'm definetely ordering a JJTesla, even to rule the tube out as the problem. Thanks!

When you get it, shake it first next to your ear. If it makes any sort of rattling sound, it is already bad and will only get worse. Quality control is not what it used to be on anything in this world, and it holds true for tubes too.

[TelePaul]

Originally Posted by Outlaws

When you get it, shake it first next to your ear. If it makes any sort of rattling sound, it is already bad and will only get worse. Quality control is not what it used to be on anything in this world, and it holds true for tubes too.

Hmm now I'm worried, I guess it's like a light bulb. Well I have some options thanks to Wade and Mike, I'll see if Mike gets back to me about the testing.

[capnkid]

Originally Posted by ocnor

Yes they are all 12AX7 type tubes which are 12 volt and use the same pinout. A JJ/Tesla ECC83 would be a good choice for your amp.

Actually RCA N.O.S. would be better.