School me on Dynaco amps

crouse

crouse

Poorly known member
There are some Dynacos for sale in BT. Unfortunately, I can't swing a purchase right now. But it got me to thinking I should learn a little about them in case I ever do get off my wallet!
So, I would appreciate any feedback on the ST-35 and ST-70 from you guys. What you like about them, what you don't like about them. Also, it would be nice to hear some feedback on the current offerings available, such as the Bob Latino amps.

Thanks!
 
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As I understand it, the ST-70 was a classic and known to be easily amenable to customizations to hot-rod them. They were certainly famous in their day and aren't badly-regarded even today. That's about all I know about them!
 
One other thing to note. I've owned or listened to over 100 tube amps and must say that the dynaco st-70 modded or factory just doesn't do it for me...

That's not to say they arnt loved by many it's just not the amp I'd choose..

I'd even go as far as saying a very well built Magnavox console amp sounds better..

Hope you find what you are looking for and if you are anywhere near Houston please come by I've got a very nice modded st-70 you can hear..

Jason
 
jbryant_77 said:
One other thing to note. I've owned or listened to over 100 tube amps and must say that the dynaco st-70 modded or factory just doesn't do it for me...

That's not to say they arnt loved by many it's just not the amp I'd choose..

I'd even go as far as saying a very well built Magnavox console amp sounds better..

Hope you find what you are looking for and if you are anywhere near Houston please come by I've got a very nice modded st-70 you can hear..

Jason
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Thanks for the response.
 
ST-35s are highly sought for their iron and are generally regarded as one fine sounding 6BQ5 amp.

I'd snag one no problem...
 
They are not my cup of tea but that has more to do with the particulars of the output tube. There are several advantages to them: (1) well understood, so easy to get help and service them, (2) good resale value and (3) reasonably powerful.

There are many other amps one could get for about the same money that to me are better (fancier EL84 models, 7591 models, SET's) but without listening to other amps for comparison to determine your tastes it is hard to recommend anything. Other amps to compare in the same class are Fisher, Scott and EICO to name but a few. My 2 cents of advice: try to listen to other AK'ers systems in your area before committing to anything.
 
I have a Dynaco ST70 and it's driving a pair of Klipsch Forte speakers.
I think the sound quality is quite remarkable. Clean, great soundstage, lotsa detail. So IMO you should be quite pleased wiht an ST70 stock refurbed or one of the many varients available. The Bob Latino product looks very apeeling. Mine is stock except for new Rs/Cs on the driver board and the few improvements installed but not modified otherwise.
Scott, fisher, eico, etc. are also highly regarded by many.
 
I have both a modded ST70 and a complete reboarded SCA-35 integrated. The ST70, with VTA board and Russian 6P3s-e tubes is a great sounding amp (I run the tubes through Klipsch KG4s..) that was easy to work on and is a delight to listen to. The SCA-35, which is basically an ST-35 amp with the PAS2 preamp circuitry onboard as I understand it, is a GEM of an amp. I put the full monty of Dave Gillespie upgrade boards in it as it needed a frame up refurb anyway, and it just sounds amazing. I'm about to pop on a SET amp-likely a Bottlehead Stereomour- so my worldview may well change, and I do NOT consider myself any kind of expert on tube tech-just a hobbyist with solder skills.. I guess I'd say that the Dynacos are a perfect starting point for getting into tubes as their costs are reasonable, they are easy to work on, and the sound is worthwhile and enjoyable. As ferninando mentions, there are many other tube amps that are each sonically and esthetically regarded quite highly. Every tube amp I've listened to/worked on had its own "sound" and character. The journey is the reward, imo.
David
 
friarmac207 said:
... The SCA-35, which is basically an ST-35 amp with the PAS2 preamp circuitry onboard as I understand it, is a GEM of an amp. ...
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The SCA-35 actually combines the power amp circuitry of the Stereo 35 with a passive line stage and an active phono stage based on the one in the PAS. The first gain stage in the SCA-35's power amp has a higher gain than the comparable stage in the Stereo 35 to compensate for the passive preamp's attenuation. I agree that the SCA-35 is a gem, even in stock form, and there are some very good upgrades out there for it.
 
jbryant_77 said:
I'd even go as far as saying a very well built Magnavox console amp sounds better..Jason
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I had been using and enjoying a modded ST-70 for a couple of years. Then I built a Magnavox 175 and did good a/b comparison. Much to my surprise, the Maggie won out and the Dynaco is on the shelf.

That's not to say that the Dyna isn't a fine amp. Maybe I was just ready for a change. :yes:

John
 
I've had the Stereo 70 and a pair of Mark IIIs. Back in the day they offered great bang for the buck and tubes were just beginning to get a bit expensive. IMO, today it's an expensive way to go. Used prices are high and a retube with anything decent is too expensive to do at the intervals where you really should. If you have to go tubes, I'd try to find something more obscure or hope you luck on a really good deal from somebody who doesn't know the current values.
 
I have two ST-70's run in mono mode each (paralleled the outputs and flip switch to mono) driving two Martin Logan Quest (6ft. tall) electrostatic/dynamic hybrid speakers. They sound awesome!

I also have a Harmon Kardon Citation II power amp (60w/ch) costing three times as much as the ST-70 and the difference is very subtle.

Like anything else in audio, it's up to your personal taste. Some like Chevy's, some like Fords, some like Toyota, etc. If you are driving to your local grocery store in a Toyota or a Ferrari, you probably won't notice any difference in performance. But once you are on a mountain road trying to handle a 90 degree curve at 80mph, then you'll see the reason for the cost difference.

I recommend you get a stock ST-70 because they are usually cheaper than a modified one. Unless you have "golden ears", you probably won't notice any difference between a stock or modded one. Also the resale value is one of the highest of all the power amps, so most likely you will recover your cost when you get tired of it and sell it.
 
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I should admit up-front that I'm probably more of an audio "historian" than "audiophile", but I think that Dynaco's basic power amps (ST35, ST70, Mark II, III or IV) are wonderful amps properly rebuilt stock. The problem is that most folks pick up a ST70 that was soldered by an amateur in the 1960's, plug it in and conclude that the sound isn't what they expected. They then do lots of modifications and notice how much better it is with the mods.

I've taken many Dynaco's - resoldered everything, replaced wiring, replaced all caps, all out of spec resistors, selenium rectifier, and often the PC board with a new production clone of the original circuit. They actually perform nicely, especially given that they were of modest cost initially. They are also great first tube amps, as all parts are readily available including cosmetic parts - and if you do a good job they will never go down in value.

I have scans of all of the original Dynaco tube manuals on my website. They are a good place to start.

http://www.the-planet.org/Dynaco.html

- Gary
 
I just can not say enough good about the Dynaco ST 70s. I have two I run bi amped and it is amazing. I have had other stuff and even sold two of them and ended up going back to them. I have the modified versions with the Latino mod and new out put tubes. I will say for the price point I would challenge anyone to find something that sounds better. Yes there are much better tube amps out there but you will spend much more on them and to me it is diminishing returns because these amps sound pretty sweet to me for sure.
 
After reading all the post here I think you have a lot more reasons to not buy a dynaco..

It has been stated over and over that they only sound good with a lot of mods well that is no longer a dynaco...

I dont know anyone that buys a Mac or marantz or any other nice tube amp and then proceeds to replace all the circuitry for better sound...

If you honestly read the thousands of post on the dynaco you will see they are over priced junk that require expensive tubes and reworked circuit boards to even be enjoyable..

I'm not against dynaco in anyway I just think people should be more honest with themself and others.. A fully modded st-70 IS NOT an st-70!!!
Jason
 
jbryant_77 said:
After reading all the post here I think you have a lot more reasons to not buy a dynaco..

It has been stated over and over that they only sound good with a lot of mods well that is no longer a dynaco...
Click to expand...

Perhaps my eyes are faulty, but I'm pretty sure I read several comments about how they sound great when stock.

jbryant_77 said:
If you honestly read the thousands of post on the dynaco you will see they are over priced junk that require expensive tubes and reworked circuit boards to even be enjoyable..
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I get that you don't like them, but this seems a little hyperbolic, IMHO.

For the avoidance of doubt: I don't have an opinion on them, nor do I expect to in the immediate future. I do have an SCA-35 on my to do pile, but Heaven knows when I'll get around to it.
 
jbryant_77 said:
After reading all the post here I think you have a lot more reasons to not buy a dynaco..

It has been stated over and over that they only sound good with a lot of mods well that is no longer a dynaco...
Click to expand...

It has also been stated that they sound good in stock circuit form if the tired caps and out-of-tolerance carbon comp resistors are replaced. That has been my experience with multiple Dynaco tube components including an ST-70, an SCA-35 and several FM-3s.

jbryant_77 said:
I dont know anyone that buys a Mac or marantz or any other nice tube amp and then proceeds to replace all the circuitry for better sound...

If you honestly read the thousands of post on the dynaco you will see they are over priced junk that require expensive tubes and reworked circuit boards to even be enjoyable..
Click to expand...

See my comments above. It's also worth noting that the Dynaco components were marketed at a far lower price point than vintage Marantz or McIntosh gear. The company's mission, as stated by their longtime tech writer Bob Tucker, was to bring "...the greatest sonic good to the greatest number."

jbryant_77 said:
I'm not against dynaco in anyway I just think people should be more honest with themself and others.. A fully modded st-70 IS NOT an st-70!!!
Jason
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So what's wrong with using Dynaco's superb iron to build something better? Audio Research did just that in the late 1970s with an upgrade kit for the ST-70, changing the outputs from EL-34s to 6L6s and replacing Ed Laurent's simple driver and phase splitter circuit with something more sophisticated, and the resulting amp drew rave reviews.
 
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So what's wrong with using Dynaco's superb iron to build something better? Audio Research did just that in the late 1970s with an upgrade kit for the ST-70, changing the outputs from EL-34s to 6L6s and replacing Ed Laurent's simple driver and phase splitter circuit with something more sophisticated, and the resulting amp drew rave reviews.[/QUOTE]

Once again that would not be a dynaco!!!
a dynaco st-70 is only an st-70 with original circuitry.. not modded..
I would agree the iron is nice but like all things you can get way better vintage iron for your money.. The chassis is to small for a proper power supply to be built.
Jason
 
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