Parasound HCA 1000 upgrade

[srinath]

I just got one of these. I was thinking of upping those power supply caps.
There is a HCA1000 on ebay now with some big silver body caps in it.
The seller doesn't know what they replaced etc.
Could someone be able to tell me what else can be modded with bigger caps in this amp ?

Thanks.
Srinath.

 

[phase]

I looked at that, and the parts that have been replaced are the ones that are best just removed.
Very nice design, built to a price point.
Probably a lot you can do here and there as far as parts go to make better smoother sound from that, as well as just for maintenance.
Main filter capacitors, local decoupling capacitors, bypasses, servo film capacitors, servo op amp, feedback resistor, diodes can be replaced for benefit, amp is fairly easy to work on.

 

[srinath]

Let me look at what the original parts that were replaced were.
Also I will see if I can replace the power supply caps to the 1000 a specs.
Thanks.
Srinath.

 

[mjstriker5]

I looked at that, and the parts that have been replaced are the ones that are best just removed.
Very nice design, built to a price point.
Probably a lot you can do here and there as far as parts go to make better smoother sound from that, as well as just for maintenance.
Main filter capacitors, local decoupling capacitors, bypasses, servo film capacitors, servo op amp, feedback resistor, diodes can be replaced for benefit, amp is fairly easy to work on.

I would be interested in a little more detail on your recommendations on making this amp better. I have a Parasound HCA 2205 that is going to need a recap soon. Since I am in there might as well have a little fun with it. Don't know how similar these amps are but I do know from looking at the schematic for my amp that is also fairly straight forward.

 

[john curl]

Keep it simple! Just raise the bias to as much as the amp can handle.

 

[mjf]

got a hca 1000a...........led lghts up, but did not want to start.
the psu electrolytics looked " bulged ", not very beautiful........
changed these , now new epcos (siemens) inside.
works without problems.

 

[srinath]

Nice, and this is one of those amps of mine I can still find - So many of em are crammed all over the place from my move in 16. Now mine has a weird hiss anytime I switch it on, I have it bridged powering a center B&W C-NT and I don't turn it on due to that hiss. Would you guys know why it may be hissing ?
Thanks.
Srinath.