can yall recommend me tubes for my vintage ampeg svt...

DrowningBrian · #1 07-19-2011, 07:40 AM

i want to do all new tubes in my 80's ampeg svt. i know dont replace it if it aint broke, but the power tubes are like 15 years old. a tech recommended me sed winged c, but they are super expensive, like $350 for sextet. he also recommended me chinesse power tubes, but he didnt mention a brand. i just want tubes that last. i know tubes make subtle changes in tone but an svt will sound like an svt regardless.
would i be ok with the sovtek 6550we, jj 6550, or tung-sol 6550? which ones have the best rep?
i just want quality tubes that last and dont cost so damn much.

the other tubes are 6c4, 12ax7, 12ax7, 12ax7a, 12ax7
12ax7
12bh7 12bh7

is the 12ax7 different from 12ax7a?
what brand for pre amp tubes do you recommend?

jmpiwonka · #2 07-19-2011, 07:51 AM

12ax7a is supposed to be a quieter version of the 12ax7.

there is a good thread on 6550 tubes in an svt.
The end-all SVT Tube post..Opinions required.

i just had a new to me svt-II gone through, it had ruby power tubes in it, 6550. i put some tung sol 6550 in it that i got from tctubes.com
my tech was satisfied with their matching, he said the tung sol seem to have a little less headroom than the ruby's had and they sound a little puffier.
the ruby's sounded way way clean, not sure how old they were but one was slightly microphonic. have a feeling i'm going to like the tung sol tubes better but i just got the head back yesterday so i can't comment on them yet.

Groover · #3 07-19-2011, 07:57 AM

Yeah, re-tubing can add-up quickly. Someone whom has recently done a tube swap may be able to chime in and give you some more recent pricings, but what your tech quoted is about how much I paid for a matched sextet about a year or so ago.

The 12AX7 and the version with the "A" are pretty much interchangeable from what I gather. I think the A came later on in years as it was supposed to be less microphonic and more suited for Audio applications, as well as something about the heating time (shorter on the A I think)

In that amp, you can also try 7025 and 5721 in place of where the 12AX7's should go - For some reason I never liked any of the 7025 that I used, but they are supposed to be super-quiet. I did like (and I have) 5721 in the first and mid slot on my amp, and I think it really gave it some beefy tone and more depth in the sound, but could all be in my head as it is subtle.

I also have a mid-80's SVT with the same tube layout as yours (SVT-HD)

DrowningBrian · #4 07-19-2011, 09:17 AM

im gonna go thru thetubestore.com

12ax7 tubes i'll use the tung-sol x4
6c4wa jan-philips x1
12bh7 electro-harmonix x2
12ax7a shuguang x1, Is this one a good tube?

would yall recommend other preamp, driver tubes?

Groover · #5 07-19-2011, 09:25 AM

12ax7 tubes i'll use the tung-sol x4 - Good Choice
6c4wa jan-philips x1 - Good Choice
12bh7 electro-harmonix x2 - Not sure, I'd suggest NOS RCA
12ax7a shuguang x1, Is this one a good tube? - Not sure. Is this last for the phase inverter? (the front 12AX7?) - If so, I think anything will work there similarly, but most people would recommend balanced triodes on this particular tube.

DrowningBrian · #6 07-19-2011, 09:42 AM

Quote:

Originally Posted by Groover

12ax7 tubes i'll use the tung-sol x4 (Good Choice)
6c4wa jan-philips x1 (Good Choice)
12bh7 electro-harmonix x2 (Not sure, I'd suggest NOS RCA)
12ax7a shuguang x1, Is this one a good tube? (Not sure) Is this last for the phase inverter? (the front 12AX7?) - If so, I think anything will work there similarly, but most people would recommend balanced triodes on this particular tube.

12ax7a, its the 2nd to last tube on the top of the amp. yeah i heard ehx tubes suck. lol.

Groover · #7 07-19-2011, 09:45 AM

If it's the one next to the 6C4, then I think that has some effects over the Mids/Channel2 - I'll have to dig through some of my old post to make sure.

DrowningBrian · #8 07-19-2011, 09:50 AM

Quote:

Originally Posted by Groover

If it's the one next to the 6C4, then I think that has some effects over the Mids/Channel2 - I'll have to dig through some of my old post to make sure.

6c4, 12ax7, 12ax7, 12ax7a, 12ax7
thats the exact order.

jmpiwonka · #9 07-19-2011, 10:08 AM

the NOS 6c4 and 12bh7 tubes are pretty inexpensive, i would use NOS in those spots...

Groover · #10 07-19-2011, 11:06 AM

Here is an old thread where there is some good information on tube functions.

SVT-HD Tube Functions?

Hope that helps.

D Bopp · #11 07-19-2011, 11:08 AM

Since you are from Atlanta, I am assuming you spoke with Andrews Amp Lab?
If you get the tubes from tubestore, and want Jeff to install them, I think he will charge $5 per tube. If you get the tubes from him, he wont charge you the extra money.

DrowningBrian · #12 07-19-2011, 03:25 PM

Quote:

Originally Posted by D Bopp

Since you are from Atlanta, I am assuming you spoke with Andrews Amp Lab?
If you get the tubes from tubestore, and want Jeff to install them, I think he will charge $5 per tube. If you get the tubes from him, he wont charge you the extra money.

yup andrews amp lab is who im gonna use. he said to let him order and install them.