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Anyone has any knowledge of these amps?
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RuSsMaN
Pudknocker
You can't get 120w (per amp) out of pair of 6550's, can you?
I've got some with MKIII Iron that Ralph Karsten (OTL Atma-Sphere) owned, then sold to Chris Ossanna (Audio Research). Dual 6550's, Altec style front end. About 60-70w each.
I'm looking to move them for $600. Cool ad, thanks for pointing it out!
Cheers,
Russ
I've got some with MKIII Iron that Ralph Karsten (OTL Atma-Sphere) owned, then sold to Chris Ossanna (Audio Research). Dual 6550's, Altec style front end. About 60-70w each.
I'm looking to move them for $600. Cool ad, thanks for pointing it out!
Cheers,
Russ
RuSsMaN
Pudknocker
If you are serious, or semi-serious, let me know. I've been pondering throwing them up on Agon / eBay in the not so distant future....
I just need to get my money out of them, I want my Spendor's more than the amps. Truth be known, I'd like to keep them ALL, but I just can't swing it financially.
Those are GE, Mullards, Amperex and RCA cleartop btw.... I figure about 300-400 in tubes alone, and the Mk III iron, hell, its worth it parts alone, no?
Cheers,
Russ
I just need to get my money out of them, I want my Spendor's more than the amps. Truth be known, I'd like to keep them ALL, but I just can't swing it financially.
Those are GE, Mullards, Amperex and RCA cleartop btw.... I figure about 300-400 in tubes alone, and the Mk III iron, hell, its worth it parts alone, no?
Cheers,
Russ
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: :lmao: :lmao: :lmao: :lmao:
RuSsMaN
Pudknocker
I think they will go, and go quick, once I go 'public' with them. I've only offered here so far.
I mean, Dynaco Iron, GOOD tubes, owned by 2 well respected amp designers, 60 TUBE watts - for $5 / watt? Seems like a no-brainer. I honestly think you'd be hard pressed to find anything substantially better, without going to the mega-buck amps.
I've got a Sharpie around here somewhere, should I try and stencil the Pioneer logo on the front?
Cheers,
Russ
I mean, Dynaco Iron, GOOD tubes, owned by 2 well respected amp designers, 60 TUBE watts - for $5 / watt? Seems like a no-brainer. I honestly think you'd be hard pressed to find anything substantially better, without going to the mega-buck amps.
I've got a Sharpie around here somewhere, should I try and stencil the Pioneer logo on the front?
Cheers,
Russ
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RuSsMaN
Pudknocker
Looks like the same Iron (top pic looks like a little rust has set in) and same Tube compliment. There is NO way they could hide the capacitance mine have under that thin chassis though. Just for a size reference, on the pic I posted of the fronts - those are 12" floor tiles in the background.
Maybe they are similar, but running a lower wattage, lower plate voltage? I know mine are high, but within reason.
They look good, heavy little F'ers I guarantee.
I don't see the 'heater' and 'b+' toggles, but maybe that is unique to the design I have, or a tweek someone added.
*edit* Just noticed - the top pic is running KT88's, I KNEW you could.
Cheers,
Russ
Maybe they are similar, but running a lower wattage, lower plate voltage? I know mine are high, but within reason.
They look good, heavy little F'ers I guarantee.
I don't see the 'heater' and 'b+' toggles, but maybe that is unique to the design I have, or a tweek someone added.
*edit* Just noticed - the top pic is running KT88's, I KNEW you could.
Cheers,
Russ
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Yep, that's my take on the situation... unless your name is Roger Modjesky, you're not going to get more than 100W out of 6550/KT88 output pairs. However, somehow, Modjesky has built an amp, he claims is like 110W or so out of these tubes... and tests (Stereophile, IIRC) reveal, that he comes DARN CLOSE to doing it, if not doing it completely.
I can't remember which amp it is now, but it's one of the Music Reference amps. I think it's up on the Music Reference website, I just haven't looked on there lately to be sure...
But, ordinary "mortals" aren't going to get that kind of power. In actuality, the ARC D75 is pretty typical- like 75-80w/ch...
Regards,
Gordon.
Thatch_Ear
Addicted Member
I believe that is the bias adjust and the red and black round jack holes close to the 6550s are the meter jacks for reading the bias. One thing that many people are not aware of is that the PS tends to be noisy. You will notice on the mono blocs of Russ's that the drivers are basically as far away from the power transformer as they could be placed on the chassis. The amplifier circuit looks to be well laid out and the binding posts for instance are copper based and were the SOTA when these were built. My 300B amp has the same BPs and possibly TOTL Vampires are better but not enough to warrent changing them.
One thing from looking at the plugs is that it appears that there are 1/4" phonos that Russ has put some RCA adaptors in, but I sure can't be posotive by looking at the photo.
One thing from looking at the plugs is that it appears that there are 1/4" phonos that Russ has put some RCA adaptors in, but I sure can't be posotive by looking at the photo.
At this website: SDS Vintage Audio Refurbishing
(that does refurbishing stuff for Dynacos)....it said the following....I wonder if that is the reason, Russman's amps have such massive caps on top.
"The Dyna MKIII has a basic design flaw that none of the other Dynaco products have. The capacitors in the power supply are not rated at a high enough voltage for the power transformer. This results in the quad cap being run over it's rated voltage every time the amp is turned on. The first section of the original quad cap is rated at 525 volts and the B+ goes as high as 585 volts during start up. This is due to the fact that the rectifier heats up and begins conducting before the power tubes heat up and start drawing power from the high voltage supply. The capacitor fatigue due to this over-voltage problem just get's worse with age, and to make matters worse, there isn't any 525 volt can caps available anymore. The amplifier doesn't have much room underneath to add a large capacitor bank either. "
(that does refurbishing stuff for Dynacos)....it said the following....I wonder if that is the reason, Russman's amps have such massive caps on top.
"The Dyna MKIII has a basic design flaw that none of the other Dynaco products have. The capacitors in the power supply are not rated at a high enough voltage for the power transformer. This results in the quad cap being run over it's rated voltage every time the amp is turned on. The first section of the original quad cap is rated at 525 volts and the B+ goes as high as 585 volts during start up. This is due to the fact that the rectifier heats up and begins conducting before the power tubes heat up and start drawing power from the high voltage supply. The capacitor fatigue due to this over-voltage problem just get's worse with age, and to make matters worse, there isn't any 525 volt can caps available anymore. The amplifier doesn't have much room underneath to add a large capacitor bank either. "
RuSsMaN
Pudknocker
I want to say the caps are 450v each (x4) for each mono. Plenty of room, not to worry.
Also, these amps have the 'heater' switch to turn on first (filament voltage only) to bring the tubes up to temperature, before hitting them with B+. I've found 1 or 2 minutes is more than adequate, a soft start if you will.
Yes, go pick up a $15-$20 jobbie at Rat Shack. I'll Bias and mark them before they leave - but you'll want to re-check after shipping. You will also want to check them periodically the first night, after a couple minutes, another couple minutes, then maybe 20 minutes....then maybe an hr....then maybe 2hrs....
Then, Ronco that mofo, set it and forget it.
Cheers,
Russ
Also, these amps have the 'heater' switch to turn on first (filament voltage only) to bring the tubes up to temperature, before hitting them with B+. I've found 1 or 2 minutes is more than adequate, a soft start if you will.
Yes, go pick up a $15-$20 jobbie at Rat Shack. I'll Bias and mark them before they leave - but you'll want to re-check after shipping. You will also want to check them periodically the first night, after a couple minutes, another couple minutes, then maybe 20 minutes....then maybe an hr....then maybe 2hrs....
Then, Ronco that mofo, set it and forget it.
Cheers,
Russ
