[spritzer]

We know that the mini tube amps have the same transformer setup (and run very hot), some of the larger tube amps (SDS-XLR for instance) have filament transformers which are way too small and the same goes for most if not all the "high current" upgrades. Some of the basic stock amps might have these 266 Hammond transformers but there is no way to really check.

Another potential issue was the common SP policy of reusing parts from other amps. Hard to know for sure if something was reused as the way the P-P amps were built it would be easy enough to just removed a whole section and put it in another amp.

 

[Skylab]

My only point from a while ago is that I felt it was going to DISCOURAGE SP amp owners from actually having their amps evaluated and repaired by proclaiming that every SP amp ever made will require complete gutting except the chassis. This was not true in the case of my amp, and I expect not true in the case of others. Mine DID require serious repair - a new trafo and some new resisters. But that was still more economical than buying a new amp of similar quality.

Saying they all have to be completely junked and can't be just repaired is likely to cause some people to just keep using amps that really need to be examined and repaired.

Bottom line is that EVERY SP amp should be checked out thoroughly by a truly qualified person/company before being used again. I am very grateful to Nate for originally pointing out that my Extreme had a dangerous flaw.

 

[spritzer]

Fair point and every amp should be looked at. Most often opening it up and posting pics is enough to identify the majority of the issues and some can be minor. I do prefer to start over as you will end up with a better amp in the end, better design with better execution. I'm certifiable though with 3K$ in DIY parts this month already so I may be living on the fringe...

 

[tagosaku]

I really appreciate this thread even though I don't understand most of it. Question from a lazy MPX owner.
I have a MPX with Piltron upgrade. (2004 built, last visit to Denver was 2008 but he didn't charge me for the fix so I am assuming he didn't lie to me.)
1. The transformer becomes luke warm at most. Nothing close to 'hot'.
2. I am usually in the room when the amp is on.

Will this make a good enough excuse not to take the unit in?

 

[Happy Camper]

Internal pics posted will let some knowledgeable people check the known areas for visual evidence of problems. Transformers aren't the only problems with these units.

 

[mrarroyo]

Quote:

Originally Posted by spritzer /img/forum/go_quote.gif Again there is a difference between fixing and properly fixing. Take the ES-1 for instance, the most horrible "design" error that has to be fixed is the shared filament supply. With the amp running like this it will eat up the tubes in no time but the fix shouldn't take anybody experienced more then a couple of hours to fix. With some shuffling of parts you can even use the same umbilicals (though I'd replace the internal wires) and it costs nothing but time. The amp is now pretty much safe to use but is it running at 100%? Far, far from it actually. With the other amps this is the same. You can fix the worst of Mikhail's mistakes easily but the amp is not running at 100%. Worse yet, you have no idea in what shape those parts are and what stresses they have suffered over the years. If the diodes have almost burnt through the PCB can you imagine what they did to all the nearby parts? Missing leveling resistors on the main reservoir caps affect other components as well. While most of the amps will probably be just fine with a few simple mods doing the same on my ES-1 would have been utter madness. Main coupling caps were 400V but should have been 1000V, damaged caps in the PSU and resistors running on the bleeding edge.

If this response is w/ regards to my post above I continue to disagree with you. You would be hard pressed to find a better technical/knowledgeable person than the individual who looked at my amp. I even asked if there was anything else that had to be done or should be done and he said no. If your response has nothing to do with my post, please disregard what I just wrote here.

Quote:

Originally Posted by nurxhunter /img/forum/go_quote.gif ... MR: hard to defend someone who simply slipped off The Big Boat and ended in the Deep End and rear ended many as he was going down. Clearly, was not and is not trustworthy. EOS. ...

If this is due to my post I fail to see the significance of your response.

 

[Happy Camper]

If you have a safe unit, yes, the amp works well with the 70x.

 

[Frihed89]

I have to agree with Miguel. We only see the worst examples, here. There are a lot of PPXs and MPX models that are doing just fine. The problems with Supras, MPX3 Slam SEs, and Extremes seen here are all fixable by an experienced tube tech. Some of the other SP "mistakes" (like the one with the fancy case with a bunch of wall warts in it) are in an entirely different category, perhaps totally or close to totally FUBAR.

It's hard to generalize across all the amps they made.

 

[CrackBerry9000]

Is there a sticky with places that can be used for repair? Maybe if people see a listing that is not on the other side of the country then having an amp evaluated and or fixed wouldn't seem like such a big task. People could add to it and rate their experiences. Seems like it would be useful anyway

 

[markmaxx]

Quote:

Originally Posted by CrackBerry9000 /img/forum/go_quote.gif Is there a sticky with places that can be used for repair? Maybe if people see a listing that is not on the other side of the country then having an amp evaluated and or fixed wouldn't seem like such a big task. People could add to it and rate their experiences. Seems like it would be useful anyway

The person that went through my balanced Extreme, did it as a favore to me and wants to remain anonymous, because of the sheer volume of work. Not everyone with a Singlepower amp that's should be gone through has posted here. Their is a lot that goes on by PM.
Also my Guy said Makhails electrostatics amps are a mess! Too

 

[CrackBerry9000]

Quote:

Originally Posted by markmaxx /img/forum/go_quote.gif The person that went through my balanced Extreme, did it as a favore to me and wants to remain anonymous, because of the sheer volume of work. Not everyone with a Singlepower amp that's should be gone through has posted here. Their is a lot that goes on by PM. Also my Guy said Makhails electrostatics amps are a mess! Too

Then obviously you would not add him to the hypothetical list, right? I wasn't really talking about friends of friends but professionals that some of you may have used. This would be a good resource for the community right?

 

[mrarroyo]

A few have used Boulder to fix their Singlepower amp.

 

[HeadphoneAddict]

Quote:

Originally Posted by mrarroyo /img/forum/go_quote.gif A few have used Boulder to fix their Singlepower amp.

I think it's Bolder? (no "U")

 

[mrarroyo]

Ok, who put that U there? It wasn't me!

that is my story and I am sticking to it.

 

[yuinlover]

Maybe we need to pm a link to this thread to all users who list "Singlepower" in their profile. Or just send it to all, better be safe than sorry.