Dynaco Mk III question help me decide

jptinc

john
Subscriber
Hi Everyone,
Currently using Marantz 15 with 7t. love the sound of the mono blocks.
I have other SS Marantz stuff 2245,2270 recapped by AKer, Salbreath (he does great work BTW)
and a 250m, 1120,1060.
But I keep on comong back to the Marantz 15 mono blocks

I would really appreciate the any and all opions on these ( I know nothing about tubes)
Going to listen to them this Wednesday. One of my concerns is, is this still a Dynaco mk III
with the mods it has. All of my Marantz is stock except for the 2245 and 2270 recaps.

here is the listing
These Dynaco Mark III Tube Monoblock amplifiers are in excellent working and cosmetic condition. Highly modified. Upgraded circuit board and power caps upgraded. Just spent $300.00 on a set of four Genelex Gold Lion cryogenic treated power tubes. Other tubes are Telefunken and NOS RCA. This pair has the rare hand-wound transformers so many lovers of these units search for. Upgraded the lamp cord power cords to Furutech silver over copper 14 gauge with top-of-the-line Wattgate silver plug ends.....HUGE difference. New OEM power switches installed. New binding posts installed, 8 ohm tap only. Come audition. $1,600. Just back from shop tube sockets cleaned, complete checkup diagnostic. Ready to go. Plinths not included. Please understand price is firm. Come audition and you will hear these superb monoblocks are worth it.
thanks -john

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my two cents worth and as per my signature, I know Dyanco stuff pretty well.
They are, in my opinion, overpriced for what they are. Too many sellers try to oversell Dynaco gear, just because they happen to be somewhat popular at the moment.
Great amps, don't get me wrong, but all those 'fancy' mods and parts does not make them worth the $ being asked for them. Not to mention they are not original Dynako MKIII's.
I am also always careful with sellers' claims of 'hand-wound' transformers and fancy power cords...yadda yadda yadda....sorry if I sound cynical here, but I've pretty much seen it all!
You can get a brand new pair of MKIII kits with a modern driver circuit including tubes for around $1400.00 plus shipping, that actually sound pretty amazing, without all the flashy plugs, cryo tubes, super duper silver power cords etc etc..
 
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Thumbs down. These are not dynaco MkIII, it is something built upon a dynaco MkIII
I'd get new ones from dynakitparts.com instead and buy music for the leftover money.
 
Thanks for the comments guys.
That's pretty much what I gathered from my readings. Mods of this type are a no no. Even more so where tubes are involved.
I just needed to hear it from someone else. Going to pass on these.
Happy New Year.
-john
 
The problem with Dynaco gear is that everyone has an opinion on it. yeah its not a stock Mark III but that may or may not be a good thing depending on your opinion. Listen to it, maybe you will like it, maybe not. Everyone tells you the board in their Dynaco whatever is the best one, and it doesn't matter which one that is. They are all better than everything else, so the only way to possibly know if its good or not is to listen. The only real performance data that exists is the stock amplifier so you can't even compare them that way.
 
Rare hand-wound transformers? Something sounds fishy. If you do talk to the seller again, ask about those. The output transformers are arguably the single most important component in the tube amp, and those that come on the stock mono blocks are very very good already.
 
If you really want one look into the VTA kits. Cheap, easy to build and already comes with upgraded parts.

Me personally, once I start hearing about all the upgrades, I start to ask myself WHY is he selling it?

I almost bought a set of the Marantz 15 monoblocks. I instead went with a fully rebuilt 250m. I have no
regrets but I would like to hear a fully restored set of 15's. The closest I had was a Marantz 18
 
Rare hand-wound transformers? Something sounds fishy. If you do talk to the seller again, ask about those. The output transformers are arguably the single most important component in the tube amp, and those that come on the stock mono blocks are very very good already.

more like rare home grown bullshit!...........
 
Thanks for the comments guys.
That's pretty much what I gathered from my readings. Mods of this type are a no no. Even more so where tubes are involved.
I just needed to hear it from someone else. Going to pass on these.
Happy New Year.
-john

in general, mods can be good if they were done correctly. But as soon as you read 'rare hand-wound transformers' and the like, walk away!!! :wtf: :crazy:
 
Rare hand-wound transformers? Something sounds fishy. If you do talk to the seller again, ask about those. The output transformers are arguably the single most important component in the tube amp, and those that come on the stock mono blocks are very very good already.

First time I ever heard of "rare, hand wound transformers" for one of these. I agree with Kward here, output transformers are the one component, above all the others, that define the character of what you hear. Dynaco's were very good indeed.

My opinion is that the box stock original circuit, restored to box stock specs makes a very fine amp indeed. A very few mods, for modest amounts of money can offer some improvement. Going beyond that is probably more about kidding yourself then any real audible improvement. Silver power cords? - why? All the power cord does is carry the current from the power outlet to the power transformer. Cryogenic tubes? - again why? What changes that would still be changed once the tube is up to operating temp?

I think you see where I'm coming from here.

Shelly_D
 
Hi Everyone,
Currently using Marantz 15 with 7t. love the sound of the mono blocks.
I have other SS Marantz stuff 2245,2270 recapped by AKer, Salbreath (he does great work BTW)
and a 250m, 1120,1060.
But I keep on comong back to the Marantz 15 mono blocks

I would really appreciate the any and all opions on these ( I know nothing about tubes)
Going to listen to them this Wednesday. One of my concerns is, is this still a Dynaco mk III
with the mods it has. All of my Marantz is stock except for the 2245 and 2270 recaps.

here is the listing
These Dynaco Mark III Tube Monoblock amplifiers are in excellent working and cosmetic condition. Highly modified. Upgraded circuit board and power caps upgraded. Just spent $300.00 on a set of four Genelex Gold Lion cryogenic treated power tubes. Other tubes are Telefunken and NOS RCA. This pair has the rare hand-wound transformers so many lovers of these units search for. Upgraded the lamp cord power cords to Furutech silver over copper 14 gauge with top-of-the-line Wattgate silver plug ends.....HUGE difference. New OEM power switches installed. New binding posts installed, 8 ohm tap only. Come audition. $1,600. Just back from shop tube sockets cleaned, complete checkup diagnostic. Ready to go. Plinths not included. Please understand price is firm. Come audition and you will hear these superb monoblocks are worth it.
thanks -john

i have included the picturesView attachment 1095839


John,

like all the others, would take a pass on the hot rodded MK3s...but thought I would also add a few comments on your Marantz 15s.

15-20 years ago, I had a large collection of every marantz solid state amp and pre amp made during their golden age, with 2 or 3 copies of each model, including a quartet of the 500s.

And would have to agree with your comments on the 15s. from a sonic perspective, the 15, 16 and 16b, were the best sounding of all the marantz amps from that period. Between the 3 amps mentioned, they were very close; can't say I would prefer one over the other. But compare any of the monoblock amps to anything else in the product line, and the monoblocks always won.

If you ever get the chance, give your 15 a listen with the signal coming from a model 7 tube unit. Very nice.
 
Hi Everyone,
Currently using Marantz 15 with 7t. love the sound of the mono blocks.
I have other SS Marantz stuff 2245,2270 recapped by AKer, Salbreath (he does great work BTW)
and a 250m, 1120,1060.
But I keep on comong back to the Marantz 15 mono blocks

I would really appreciate the any and all opions on these ( I know nothing about tubes)
Going to listen to them this Wednesday. One of my concerns is, is this still a Dynaco mk III
with the mods it has. All of my Marantz is stock except for the 2245 and 2270 recaps.

here is the listing
These Dynaco Mark III Tube Monoblock amplifiers are in excellent working and cosmetic condition. Highly modified. Upgraded circuit board and power caps upgraded. Just spent $300.00 on a set of four Genelex Gold Lion cryogenic treated power tubes. Other tubes are Telefunken and NOS RCA. This pair has the rare hand-wound transformers so many lovers of these units search for. Upgraded the lamp cord power cords to Furutech silver over copper 14 gauge with top-of-the-line Wattgate silver plug ends.....HUGE difference. New OEM power switches installed. New binding posts installed, 8 ohm tap only. Come audition. $1,600. Just back from shop tube sockets cleaned, complete checkup diagnostic. Ready to go. Plinths not included. Please understand price is firm. Come audition and you will hear these superb monoblocks are worth it.
thanks -john

i have included the picturesView attachment 1095839
It seems like a "high" price for these amps but the seller put quite a bit of money into it. So, breaking it down i would guess around 1000 bucks for the original pair, since they look pretty nice cosmetically. and around 600. for the tubes and new parts (Mundorf caps can set you back a bit) although i think spending money on audiophile power cords is a bit of a waste. So, the amp looks like a complete rebuild.
While the term hand wound is dubious it is not disingenuous since the work to set up the transformer winding machine and spools is certainly done by hand, so a bit of advertising hype.
In the end, if you are considering KT88 PP monoblocks, of which there are not many around, the 1600 for a completely rebuilt pair may be a reasonable price. If you could find out who did the work and inspect it in detail it may change your mind if the sound is as good the seller claims.
 
Here is my opinion,although I quoted myself just out of laziness;) Frankly,you can do far better....



I would like to add the following term to the AK Glossary: BSA ( BULL S**T ARTIST )

BSA: This term generally applies to sellers and/or flippers who engage in extremely ''flowery'',long winded prose to describe whatever piece of crap they are selling.

See also: exaggeration, overstatement, magnification, embroidery, embellishment, excess, overkill,rhetoric,hyperbole

Thanks,

Art
 
That set of amps, as with all of that series had too much B+. They put the filter caps at risk during warm up. The new boards may be worth it; it is not so difficult to top the original. IMO, there are no *REALLY* good ones...there are lots of 'Better' though. For the cost, I'd go elsewhere.
cheers,
Douglas
 
I would very much like to know:

How this: ''Upgraded the lamp cord power cords to Furutech silver over copper 14 gauge with top-of-the-line Wattgate silver plug ends.....''
Equates to this: ''HUGE difference''
Despite this: ''New OEM power switches installed''

I'm guessing that when you've got plugs and cables that good, even a crappy 25¢ plastic slide switch is no obstacle:rflmao:
 
That set of amps, as with all of that series had too much B+. They put the filter caps at risk during warm up. The new boards may be worth it; it is not so difficult to top the original. IMO, there are no *REALLY* good ones...there are lots of 'Better' though. For the cost, I'd go elsewhere.
cheers,
Douglas

HUH??...would you like to elaborate on that?
 
How exactly do they have "too much B+" if they are operated within the range of AC mains specified in the original Dynaco manual? If you refer to turn on surges, it can't be an immediate problem, as these amps ran for years before failures set in, or at least that is my impression. Would not a very inexpensive thermistor in series with the power transformer primary help the situation without trashing the whole series?

That 'original design' flashed voltage well over the cap's ratings as it came up to operation( as in cathodes warmed up ), was hard on power tubes due to the level at which it runs the screen grids, and it sags a fair bit due to penny-pinched PS components. It was another of the low end, horsepower race amps, and as such did pretty well.
cheers,
Douglas
 
If you don't mind the look, there is pair of Allen Organ 75s on ebay for that money.
That would be something else than a Dynaco, left alone a clone.
 
Dynaco MKIII uses a GZ34/5AR4 Rectifier.Indirectly heated cathode. HV and load ramp up together. No surge whatsoever.

I have yet to have a TS 6550, a GE 6550A or a GEC KT88 beat *ANY* GZ34 to conduction temperature. Not metal based ones, not the big base f31, or the f32/f33 later versions. There was always a surge.

As far as that old, 'it was always like that, and they didn't break very often'...bad engineering is still bad engineering. A solid PS that delivers current to the load at the operating voltage those amps run at, *AND* does not flash over the voltage ratings is quite possible. It will be heavier, and more expensive though.
cheers,
Douglas
 
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