No bad thing considering the scarcity and commensurate price of genuine NOS, or really good used valves .
SET amp owners thread
- Thread starter bonzo75
- Start date
it is german post tubes, they are trimmed for longevity if you don't squeeze them out for maximum poweroutput last a lifetime. ten years ago they were really expensive 700€ per tube nos unplayed today they are cheaper. Thank God..
on the subject of the construction of a tube amplifier because it was discussed here
A klangfilm v 402 amp is a masterpiece, learning from the past how to build a good dead quiet amp. These guys know exactly how to do exsample.
Thats great for current amplifier owners … They must have reached a high water mark back when I was acquiring them .. maybe 10-12 years back …ten years ago they were really expensive 700€ per tube nos unplayed today they are cheaper. Thank God..
It seems that this is a PP amplifier. The PP amplifier is easier to make silent.
It was easier then, tubes were not in short supply, so soft-start and electronic bias were not done, there was no remote control, etc. And it is difficult to do without PCB and it is not necessary.
And the amplifier itself must be made without a PCB.
Why are you so married to this Audion amp that seems to cause problems? Just try another SET…there are several quite good ones out there.
I guess its hard to throw away $12,000. Its the hum that bothers me. Not the tone. I have a lot of tools. If I can make a normal case and drop the parts onto it, then have someone make a $500 power supply, I may be able to rid the issue. I hope. Or I have wasted $12,500.
It can buzz not only because of the power supply. Improper ground connections also cause buzzing. Bad PSU gives 100Hz hum, ground hums like 50Hz (in Europe).
was this your first SET? First set would ideally be something like a mastersound. Great value for money. Then, keep auditioning till you hit one that knocks your b@@@@ off. And mastersound sells off
if the hum is coming from the power supply, it's easy to find out. you pull out all the tubes and turn on the amp. if you hear humming in the speaker, this is induced via the output transformer. if not it comes from the circuit maybe a defective coupling capacitor in the stages. a ground loop is often caused by unshielded rca cables or different grounding concepts of the connected devices. in rare cases interference from mains transformers positioned too close to output transformers or interference from halogen lamps (transformers).
to rule out that the problem comes from outside the device. buy a cheap rca plug, then solder a jumper wire signal pin to ground in it. put it on the amplifier input (short-circuit plug) switch on the amplifier the when hum is gone then it comes from outside the amplifier is ok.
just to one try, please disconnect the grounding of the powercable to amp and hear if the hum is gone. if it's gone you have a ground loop, these are difficult to get a grip on. then immediately reconnect the grounding there are life-threatening voltages. This is how I would proceed to find the error without measuring devices.
if you don't trust it and it's dangerous for you, let a professional come to your house and do it. Good luck
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Seems like at that point let the builder use the iron and parts they like, otherwise it could end with a conversation like " doesn't sound great but did what I could with those parts you gave me".
Where did you get this amp? If used I can sort of see that you got stuck. But if its new, the manufacturer has a warranty, right??
And even if it's out of warranty, good people would want to help you, provided the amp hasn't been abused. Seems like the manufacturer could be a better line to solution than what you are trying to do. Or at least a first step?
I see now, thank you for straightening me out on what you are up to. When you jump into some of these threads half way you miss the context of what people are saying.
Thank you also for your mentions on more neutral components. I havent heard most of them. I did think the sound in the Air Tight, Wolf Von Langa and Primary Control room at last years Munich Hi End show was excellent! At the end of the day it is all about the whole system.
I think your objective to get transparency to recordings is admirable. You are right they should not all sound the same and the system should be able to portray the differences. I would have to say that Shindo is guilty of imposing its lovely house sound on recordings so I understand why this colouration is not acceptable to you.
In principle I agree with you but I find so many of today's hi end systems brightly etched on the top, cumbersome at the low end and devoid of personality and life so at the present time I find the overall musicality of the Shindo a relief.
Its old. Used. Was rebuilt by the Importer to the US. Did not resolve any issues.
Rebuilt by a local guy and at the time added wide bandwidth transformers. That helped a lot, but there is still hum.
Shorting the input there is hum. its small. Pretty much close to I could live with it. But I would prefer it not be there. Its heard at the chair.
I forget if the hum is there when I remove the signal or driver tube. I would have to hook them up and try to confirm.
I know for sure there is power transformer injection of noise. I have done some shielding work around the power transformer (toroid) and heard a large reduction in noise. Not all.
If you don't lift the grounds, there is a high level of hum.
When you lift the grounds, there is an unacceptable level of hum. But it is much reduced.
Part of my thinking of putting it on a bread board. If I do, my local guy says it shaves hours upon hours of time for him to scope and test the equipment. My issue is its hard to find someone to tell you how to lay out the breadboard as I could create all sorts of issues by improper spacing and layout. But hey, I can't usually help myself so at some time I will take a stab at it. In the meantime, I am really waiting on Scott Sheaffer with Found Music to bring a Blade amp to Seattle for people to hear. That is what I will probably purchase. But some others look interesting to try.
FWIW, my local tech at one time said it was leaking voltage to ground. He wants $2000 to chase it down. Most of that is time to break the amp down based upon the poor design that does not allow servicing without dismantling the amp.
Rex
Rebuilt by a local guy and at the time added wide bandwidth transformers. That helped a lot, but there is still hum.
Shorting the input there is hum. its small. Pretty much close to I could live with it. But I would prefer it not be there. Its heard at the chair.
I forget if the hum is there when I remove the signal or driver tube. I would have to hook them up and try to confirm.
I know for sure there is power transformer injection of noise. I have done some shielding work around the power transformer (toroid) and heard a large reduction in noise. Not all.
If you don't lift the grounds, there is a high level of hum.
When you lift the grounds, there is an unacceptable level of hum. But it is much reduced.
Part of my thinking of putting it on a bread board. If I do, my local guy says it shaves hours upon hours of time for him to scope and test the equipment. My issue is its hard to find someone to tell you how to lay out the breadboard as I could create all sorts of issues by improper spacing and layout. But hey, I can't usually help myself so at some time I will take a stab at it. In the meantime, I am really waiting on Scott Sheaffer with Found Music to bring a Blade amp to Seattle for people to hear. That is what I will probably purchase. But some others look interesting to try.
FWIW, my local tech at one time said it was leaking voltage to ground. He wants $2000 to chase it down. Most of that is time to break the amp down based upon the poor design that does not allow servicing without dismantling the amp.
Rex
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