Pass Labs XVR 1 upgraded pot replacement ?

One of mine's noisy too - use contact cleaner. I replaced the stock power supply diodes with hexfreds.

I wouldn't replace the pots as I find I need very fine adjustments here and I'm not sure the typical 24 step pot or even a 32 would be discrete enough. If you're still inclined I'd use a DACT unit as they're small & they'd fit. let me know waht you do.

For a technical thread with schematics on an XVR-1 copy see below.

http://www.diyaudio.com/forums/showthread.php?s=&threadid=27651&perpage=25&highlight=&pagenumber=1

Hello Barry,
Thank you.
Hexfreds are on my list.
I have contacted Parts Connexion and they suggested the DACT C2-1 device, also. Until my XVR 1 is in their shop only then PC can tell me if the DACT's will fit and operate properly.
The other reason apart from noise pots, I would like to find out if resistor networks volume attenuators are of better sonic performance in this case.

Sadly the hexfreds are not a drop-in as the XVR-1 uses a bridge package not discrete units.

Looking at the data sheet & the unit inside you've got about an inch of clearance behind the pots so I think you'll be ok fit-wise.

The more problematic issue could be dB attenuation. As you know the pots come in two types -- fine w/ 12 dB total attenuation and standard with about 70 dB. If your current settings on the dial are close (e.g. amps with same sensitivity) go with fine & .5 dB steps if you can (My system is tri-amped and 1 of the amps varies quite a bit in sensitivity).

You should notice a sonic difference - the pots are in the signal path according to the schematic. I've replaced ALPS Black Beauty carbon pots with metal film ladder attenuators on preamps with very good sonic results. Pass uses good parts but the DACTs are suppose to sound very nice.

Please let me know how this works (e-mail me)- I might try it on one of my units. Oh, PC shouldn't charge much for labor on this ($~75 max?). It's 12 simple solder connections. Even a caveman could do it. Have them send the old parts back to you in case you ever want to sell it.

Hello Barry,
Thank you.
Yes, of course I will let you know how it works out.
My XVR 1 will be shipping out to PC first week Sept.
Do you feel besides, the Hexfreds, by replacing the psu filtering caps with better unit will make any differences.

thx Terry

The Hexfreds (or schottkys) didn't make a huge difference but they're easy to change and not expensive.

Replacing the psu caps is not possible as some of the uF values are very large with no ready higher-end substitutes. There's probably something else in your system worth throwing money at than this.

It might be possible to change some of the smaller hi & lo pass filter caps. That may not be worth it either (they're ok sounding). Send Chris J. the MOX link I sent you & see what he says.

Hello Barry,
Thank you again for your kind reply.
Yes, I will skip the PSU caps and only do the pots and diodes.
By any chance, would you know the resistance value of the stock pots on the XVR 1 ?
I presume that the value is the same on each pot.

Thx Terry.

Well if tou open the unit up you'll see that they're PEC (Precision Electronic Components) 10K pots made in Canada and yes they are all the same value.