Ampeg SVT3-Pro: Which Tubes Are Best

roqblok · #1 12-24-2011, 10:40 AM

Greetings,

I bought my Ampeg SVT3 Pro used about 2 years ago. My guess it's was originally purchased in 2007 (I saw a QC label inside the amp). For some reason I think it was originally made in St Louis so maybe it's older? So over the last year I have been playing about 3+ hours per week and the sounds seems like it's been getting muddier.

I don't know anything about tubes and have been trying to read up on them here and on tubestore.com. The info seems to be a bit subjective and I have also read only the first preamp tube is important.

I have no idea if the tubes that are in my amp are original or not. Currently inside are:

1 - Groove Tube 12AX7
2 - Sovtek 12AX7
3 - Sovtek 12AX7
4 - Electro Harmonix 12AU7
5 - Sovtek 12AX7

I play punk/alt covers and have a 4x10 Ampeg Classic cabinet.

So my question(s) are:

1. Is there a preferred tube?
2. Do the gold tipped tubes make any difference?
3. Should I ordered them 'matched'?

btw, recently I also noticed that I have to play with the EQ set to on. When I play with it in bypass the EQ seems to turn on & off for some reason. This was my original rational that maybe something was going wrong with the tubes.

Thanks in advance for all your thoughts and advice

**B-string** · #2 12-24-2011, 02:00 PM

JJ's, Gold Lion, SED some EH offerings are pretty decent, TungSol re-issues. For the 12AU7 you should be able to still reliably find NOS (New Old Stock) valves: RCA, Silvania, GE, ect.
Gold pins mean very little except more cash spent. NOS 12AX7's are available and some grand ones get REALLY expensive, just saw last night a Bugle Boy 12AX7 sell for $800.00
The EQ cutting in and out is probably not tubes.

grendle · #3 12-24-2011, 03:43 PM

EH imo.

JimmyM · #4 12-24-2011, 03:52 PM

Quote:

Originally Posted by roqblok

1. Is there a preferred tube?
2. Do the gold tipped tubes make any difference?
3. Should I ordered them 'matched'?

btw, recently I also noticed that I have to play with the EQ set to on. When I play with it in bypass the EQ seems to turn on & off for some reason. This was my original rational that maybe something was going wrong with the tubes.

1. Not really. B-string 2 gave you a few good brands to check out.

2. No.

3. No, only power tubes need to be matched.

Not sure about the EQ but try cleaning your effects loop jacks. Sometimes that can cause shorting and other types of weirdness. Also, spray some deoxit on the EQ on-off switch. It could be dirty, too.

roqblok · #5 12-24-2011, 05:27 PM

Guys, Thanks for the messages. I appreciate the info.