supply change

[kingfisher]

Hello Power supply builders
I have a question about my Sony intigrated amp. Can someone buy and off the shelf power supply and replace the one in my amp? providing it is designed beter then Original design will it better my sound?
I saw an ad for kit type supplies and was wondering about this. Also, is it possible to change the input section to a Tube based unit and create a hybrid? I'm grasping at straws, maybe? Thre is nothing wrong with my system, only wish to elevate the quality.
Kingfisher

 

[ChrisA]

Hello Power supply builders
I have a question about my Sony intigrated amp.

Yes of course you can do anything you want to the amp up to just replacing it with another one.

But before you replace anything you need to characterize it. Measure it and then be able to describe why it is not good. Next come up with a specification for the improved supply

Don't expect any replacement to fit inside the same chassis

About the tubes. What you are talking about is a tube based "line level amp" or "preamp". The best way to try would be to get/build it in another chassis then run your source through that. Turn the volume of the present amp way down so the new tube pramp supplies some gain. An amp running at near unity gain have not much of a sonic signature. Building a tube basedline level gain stage is an easy first tube project.

What you draw it all out and compute the costs you may find "replacing it with another one." cost effective. The other advantage of replacement is that during the weeks or months that you work on it you still have something to listen to.

 

[kingfisher]

Hi ChrisA, I bought this amp at a fleamarket for $30 and thought that it works well, but could be improved on. I had a CJ and a Sonic Fr. preamps in front of Marchand Electronics MB501 Mono blocs in the past and liked their sound. But the Sony is a but sharp and not as smooth as these. For the money I figured "Waht the heck!" At best, given your advice I will only consider the Power supply. If a no go, then scrap the idea and move-on!
Thanks for your input.
Kingfisher

 

[ChrisA]

Hi ChrisA, I bought this amp at a fleamarket for $30 and thought that it works well, but could be improved on. ...

My bet is that the harshness is caused by the hugh amount of negative feedback they used on old solid state amps and a new power supply would not address that.

 

[Th3 uN1Qu3]

I wouldn't say it's the NFB amount. Check any capacitors in the signal path, replace as needed. Check for power supply sag under large transients, if it's more than a few volts it could benefit from a bigger transformer.

 

[ChrisA]

I wouldn't say it's the NFB amount. Check any capacitors in the signal path, replace as needed. Check for power supply sag under large transients, if it's more than a few volts it could benefit from a bigger transformer.

He describes the sound as "harsh". That means highs that do not sound musical. Sag realy does not sound bad and some even like the compression effect. Big filter cps go bad but couplers don't. I'm betting the sound is because it was simply designed that way at the factory. Is so a new power supply will not help

But I agree with what you say __measure__ it first. Don't go fixing things untill you can point at a number you don't like

 

[AndrewT]

But I agree with what you say __measure__ it first. Don't go fixing things untill you can point at a number you don't like

Yes.
A product that performs within specification is likely to please.

If it is out of specification, this may be audible.
If it is seriously out of specification, repair it.

Don't start modifying replacing until you know what is wrong.