pre-amp tubes

[Lonewolf]

I looked at my amp tubes because I wanted to buy a set to have as spares. They now have a 12ax7, a 12ax7wa, and a 12ax7. The 12ax7wa is on the clean channel. I found the specs for the tubes for this amp and it says they should all be 12ax7wa, in there. Would the sound or anything else be different if I bought all the same tubes, or should it stay the way it is? The amp is a ycv40wr. Thanks for any replies.

[NB-SK]

Who, where, and when they were made, that's the main difference. They are also known as ECC83, ECC83s, CV4004, and 7025.

I really like the Tungsol reissues. The Tesla ECC83 was also nice at a few dollars less a tube.

For a nice cleaner sound, I don't use a 12ax7 at all but its lower gain siblings, the 12at7/ecc81/cv4024 and the 5751. I've got a couple of NOS Mullard 12at7 (nice middle 'bark'), a bunch of NOS Jan 12at7 from the early 80s (nice even sound) and some NOS Jan 5751 from the early 70s (some stores claim this was SRV's favorite preamp tube) that I really like.

What do you play? We might be able to make some suggestions.

[Lonewolf]

The 12ax7a's are Penta's made in China. The 7025/12ax7wa is a Sovtex. The amp was bought new last November. I play 80% rythym on the clean channel, with chorus, delay and reverb pedals. Also is there any difference in a 6l6gb, 6l6b and the 5881wxt? I've been a solid state man till last fall, and am new to tubes.

[NB-SK]

I'm no expert, but I've got some info that might come in handy.

You can experiment with the pre-amp tubes. Usually the tube placed in position one in the preamp chain has the most affect on the sound of the amp, so you don't have to buy a full set 12ax7 to find out which one sounds best for you. You could also use a 5751 or 12at7 as a reverb driver if you feel the reverb has too much gain.



What you've got there are all 6L6 tubes.

I'm not sure if that amp is self biasing, but the different power tubes will also affect the sound. I remember reading that some 6L6 type tubes are not great replacements for others. Something to do with the bias (some will say you need to bias your amp every time you change power tubes, even if they are of the same type).

I have a Jan 6L6GAY (solid, maybe not the best sounding tube but it's quiet and can be had for close to nothing on Ebay. Besides, there's something cool about using a 50 year old tube in my amp), some NOS Tungsol 5881 (nice nasal sound. I can see why these are sought after) and NOS GE 5881 (slightly more even sounding than the Tungsol). I also have a reissue Tungsol 5881 that is really close to the NOS, but maybe even better (it's a bit punchier, which I like) (the reissue sounds great with the reissue Tungsol 12ax7 (one of the best 12ax7 you can find (NOS or current production)).

Keep the 5881wxt if you play high gain/distortion stuff. They may not produce the cleanest of tones (and they do snap crackle and pop sometimes), but they are well suited for the heavier music because they are built tough. They were designed to be used on the servodirection system of Soviet Air Force planes, if I remember correctly.

[gpower]

I'd suggest contacting Bob at eurotubes.

http://www.eurotubes.com/

He's great to deal with and an excellent source of advise for tube recommendations for your particular amp and playing style.