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previous: Wyatt Okay, I've a ST-70 on it's way to m... -- 6/16/1999 6:37 PM

Re: Dynaco ST-70's, some ?????

6/16/1999 11:52 PM
Steve M.	Re: Dynaco ST-70's, some ????? Hi Y, > My questions were what do you all use with it? I found a matching PAS-2 preamp to go with it. The CD player is low-end Sony. > It's eventually going to be part of a simple set-up for > music in my bedroom. That means it will probably be > paired up with a variable output CD player (Dynaco > CDV-Pro?) and some speakers and that's it. It is supposed to be a 35w amp, but the tech who fixed it up a while back said it was closer to 25w, FWIW. IMHO, this amp sounds pretty good with a decent set of bookshelf speakers. > But in the meantime, I was wondering about preamps and > such. Do those of you who have one use a tube preamp...SS > preamp, Dynaco PAS 2 or 3, etc.? At first I had it paired with a $75 AGI 511 SS preamp. Now it is paired with the aforementioned PAS-2. > And if I did pair it up with a nice but affordable SS > preamp for now, will the tone suck? Yes. I don't claim to have golden ears, so if I can tell a difference, there probably is one The SS pre sounded a little flat for the want of a better word. The PAS 2 sounds much more lively and warm. Of course this would depend on the preamp, too. > Also, any suggestions on tubes. Are the Sovtek 7199's any > good or should a pay for NOS? The Sovtek 7199s are re-pinned 6BL8s according to Ned at Triode Electronics, a similar tube with slightly different ratings. The amp will work best with NOS 7199s, but they are getting pricey, upwards of $25 each the last time I checked. Mine has been modified with the Sound Valves/Sound Values replacement driver board. It isn't an modification of the circuit per se, it merely corrects some problems of the original board has 30+ years later. Mainly drifing carbon comp resistors, leaky coupling caps, and inferior material for the PCB substrate. It uses the 6GH8 tube which is similar to a 7199, but with a different pinout. I just bought a lifetime supply at a hamfest for $1 each. The 6GH8 has the same pinout as the 6BL8 and 6U8. Some people don't think that the 6GH8 sounds as good as the 7199, FWIW. If you can afford it, I would recommend a replacement driver board, or at the very least upgrading all the components on the original driver board. Ned at Triode Electronics sells a nice replacement board using EF-86s and a 12AU7, I believe. http://www.triodel.com Check it out. > And, what are your opinions of current model EL34's for > HiFi use? Mine has NOS Siemens EL-34s in it. I've also heard that the Sovtek EL-34WXT and the Svetlana EL-34 sound great in this amp. Maybe someone else can elaborate on the various differences in sound. > Thanks for any answers, guys. No problem, let us know how it turns out for you. Regards, Steve

6/16/1999 11:52 PM

Steve M.

Re: Dynaco ST-70's, some ?????

Hi Y,

> My questions were what do you all use with it?

I found a matching PAS-2 preamp to go with it. The CD player is low-end Sony.

> It's eventually going to be part of a simple set-up for

> music in my bedroom. That means it will probably be

> paired up with a variable output CD player (Dynaco

> CDV-Pro?) and some speakers and that's it.

It is supposed to be a 35w amp, but the tech who fixed it up a while back said it was closer to 25w, FWIW. IMHO, this amp sounds pretty good with a decent set of bookshelf speakers.

> But in the meantime, I was wondering about preamps and

> such. Do those of you who have one use a tube preamp...SS

> preamp, Dynaco PAS 2 or 3, etc.?

At first I had it paired with a $75 AGI 511 SS preamp. Now it is paired with the aforementioned PAS-2.

> And if I did pair it up with a nice but affordable SS

> preamp for now, will the tone suck?

Yes. I don't claim to have golden ears, so if I can tell a difference, there probably is one

The SS pre sounded a little flat for the want of a better word. The PAS 2 sounds much more lively and warm. Of course this would depend on the preamp, too.

> Also, any suggestions on tubes. Are the Sovtek 7199's any

> good or should a pay for NOS?

The Sovtek 7199s are re-pinned 6BL8s according to Ned at Triode Electronics, a similar tube with slightly different ratings. The amp will work best with NOS 7199s, but they are getting pricey, upwards of $25 each the last time I checked. Mine has been modified with the Sound Valves/Sound Values replacement driver board. It isn't an modification of the circuit per se, it merely corrects some problems of the original board has 30+ years later. Mainly drifing carbon comp resistors, leaky coupling caps, and inferior material for the PCB substrate. It uses the 6GH8 tube which is similar to a 7199, but with a different pinout. I just bought a lifetime supply at a hamfest for $1 each. The 6GH8 has the same pinout as the 6BL8 and 6U8. Some people don't think that the 6GH8 sounds as good as the 7199, FWIW. If you can afford it, I would recommend a replacement driver board, or at the very least upgrading all the components on the original driver board. Ned at Triode Electronics sells a nice replacement board using EF-86s and a 12AU7, I believe.

http://www.triodel.com

Check it out.

> And, what are your opinions of current model EL34's for

> HiFi use?

Mine has NOS Siemens EL-34s in it. I've also heard that the Sovtek EL-34WXT and the Svetlana EL-34 sound great in this amp. Maybe someone else can elaborate on the various differences in sound.

> Thanks for any answers, guys.

No problem, let us know how it turns out for you.

Regards,

Steve

Replies:

dan Re: Dynaco ST-70's, old hardware -- 6/17/1999 3:52 AM