Pass Labs heatsinks temperature

My XA60.5 needles ran a little left of center at idle as well. If they're not moving, I wouldn't be too concerned. There is an article on the Pass site titled "Leaving Class A" that might be worth a read.

Icorem,
Judging from your report, it "looks" like your amps are okay. The fact that they aren't bouncing means you are not leaving class A.

Seems like I remember my manuals saying the heatsinks should be "around" 50 degrees "F" above the ambient temp. Don't know what that converts to in "C". My heatsinks run a little hotter in the summer than in the winter. What is your room temp these days?

Icorem - I though you are from the US. If you are from Israel, sending them back for sth as trivial as biasing, would be a total waste of money and effort. Just take the amps to your local tech, or ask one to come over.

Here is XA-30.5 bias procedure for reference purposes only - it is really easy !

(pls note that you need XA-60.5 biasing manual to perform this task on your amps !)

1) Measuring across test points adjust bias for each channel to 125mV. Pay attention to DCO across the two speaker terminals and from each terminal to ground, aim for as close to zero as possible. (P1 and P2 on the socket mounted module adjust offset.)

2)Replace cover allow unit to warm up to 53 degrees C at the heatsink, which wil take a couple hours.

3)Final adjust which will take several attempts with time lapse to allow For stabilization of temperature, and bias which tracks temp as a NTC.

4)Target Bias is 135 mV, again paying attention to DCO, absolute and differential

PS. From what I remeber, I needed 4 Digital Multimeters (you can get the cheapest one you could fing from ebay - no name ones are ~ $10 each) to perform biasing on my XA-30.5:

- one to measure DCO across the two speaker terminals
- one to masure DCO from each terminal to ground
- one for each of two bias test points (A nad B)

Hi. Im not sure if this helps at all, but i have a pass xa30.5 and it just gets warm to the touch. After an hour or so the whole thing is warm, certainly not hot. even the whole thick metal front panel is warm as well as the fins. im no expert on amplifiers, but it seems fine and has always reached that temperature since the day i acquired it five years ago.
i observe that the sound quality is not optimal until it is warm. i would be very cautious about opening a piece of kit like that. i wouldnt attempt it.
regards.

I have had two XA30.5 amps and I can/could keep my hands
on the heatsinks for as long as I want/wanted. Not sure
what temperature they actually get/got to, but it definitely
is not as hot as advertised. My hot water heater is set
to around 120F and our hot water is much hotter (by the time
it gets to a faucet).