Oh Dear...Replacement needed for Caiman big smoothing cap?

[Covenant]

Ask Jerry if he still likes his.

Yes-with a capital Y!

[Ali Tait]

Anyone have links for the John Swenson PS?

[Covenant]

Actually scratch that Rob, the next job is swapping out the Murata 12V reg for a non switching discreet type, probably one of the Dexa'a.

Theres a low high freq "whistle" in the background after fitting the Gator board, and after asking around it seems to be switching noise being picked up by the Gator board, as its not there with the original.
Any other potential reasons for this?

I had assumed the Gator board to be the culprit but as the whistle is there with two different units (and different psu's), I guess its just my Dac with all its modifications adding up to the noise.
Maybe a case of with the Gator board its a more open window letting more crap in?
Dunno...

Going to swap out the Reg anyway methinks.

Baby steps....before I take on a PSU build project!

Gaz,
Your dac and mine must be pretty similar as we have followed the same upgrade path more or less. I dont get any whistle. Have you tried moving around SMP supplies on other bits of equipment to see if you can alter or eliminate the problem as it might be RF?

[Covenant]

Anyone have links for the John Swenson PS?

http://forums.slimdevices.com/showth...t=82648&page=4

[Ali Tait]

Cheers Jerry.

[leo]

Strange regarding the Murata's, I'm not sure of the switching frequency, maybe its in the audible range for certain ones and not for others? I presume you all use the same model? not really looked at the Murata's much tbh.
Thing to note is that although a good discrete op-amp can give best sound , IC based op-amps tend to have better PSRR than basic discrete citcuits so you need clean as possible supplies for them for best results.

A discrete super reg would be the best choice although obviously more costly. I had wonderful results using Paul Hynes regulators with a Sabre based dac, as already mentioned Martin had good results with the Dexa's , Audiocoms newest ones are also supposed to be very good so you have plenty to choose from.
You could also try a few of the simplish diy ones if your feeling brave, I doubt they'll be as good as the best commercial discretes though

[leo]

BTW I tried John Swensons diy 5v discrete regs, they was pretty good

[Gazjam]

Gaz,
Your dac and mine must be pretty similar as we have followed the same upgrade path more or less. I dont get any whistle. Have you tried moving around SMP supplies on other bits of equipment to see if you can alter or eliminate the problem as it might be RF?

Worth a go Jerry, I'll try that.

Yeah, our dacs must be pretty close...I did the "wire" mod (well Ali did ) to remove the resistor behind the 12V Reguator..dont know if that might have done something which the Gator board might have revealed?

Its annoying actually...especially on quieter pieces, quite noticable.

[Gazjam]

Gaz, you ought to make one of the super regulators with a 7805. Have a look on Pink Fish. I can send you the bits you need. Costs about £10. Mind you, you could be waiting a long time if my performance with the caps for the passive mod is anything to go by

Hi Rob,

caps for passive mod? Cant remember anything about that old chap

I scoured PFM and theres a lot of threads about the "super regulator".
TOO many actually and there seems to be different types?

From PFM I got a link to this (useful?) page, but I don't know where to look?
http://www.gammaelectronics.com/powe...hi-fi-diy.html

Could you help out a hapless Jock and point me in the right direction?

ta.

[Gazjam]

Strange regarding the Murata's, I'm not sure of the switching frequency, maybe its in the audible range for certain ones and not for others? I presume you all use the same model? not really looked at the Murata's much tbh.
Thing to note is that although a good discrete op-amp can give best sound , IC based op-amps tend to have better PSRR than basic discrete citcuits so you need clean as possible supplies for them for best results.

A discrete super reg would be the best choice although obviously more costly. I had wonderful results using Paul Hynes regulators with a Sabre based dac, as already mentioned Martin had good results with the Dexa's , Audiocoms newest ones are also supposed to be very good so you have plenty to choose from.
You could also try a few of the simplish diy ones if your feeling brave, I doubt they'll be as good as the best commercial discretes though

Thanks Leo.

Its a good clean linear supply feeding the Dac so I would hope discreet regs would not be wasted.
The Dexa's can be sourced for about £25, do the Paul Hynes come in at much more?

Also, would they fit inside the Caiman case?


ta.
G.