Greetings! The meters on both of my XA60.5 amps are running significantly off center, one worse than the other per the attached pic. Meanwhile the XA30.5 is fine.
Should I be worried? Is there an adjustment that I can perform?
Thanks!
John
Should I be worried? Is there an adjustment that I can perform?
Thanks!
John
Did this just happen, or have both gradually drifted off?
Seems like it might be power supply related. Or a leaky capacitor.
Is there any DC voltage on the speaker outputs? Hopefully not.
Seems like it might be power supply related. Or a leaky capacitor.
Is there any DC voltage on the speaker outputs? Hopefully not.
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question:
ready to open the case and check few points, using your mV-meter?
that, just to be sure that amp is in order and you need to deal just with front meters ....... or maybe you need to dial-in amps first..........
what's temp on heatsinks, in temp. equilibrium, and what's temp of room, in same time?
ready to open the case and check few points, using your mV-meter?
that, just to be sure that amp is in order and you need to deal just with front meters ....... or maybe you need to dial-in amps first..........
what's temp on heatsinks, in temp. equilibrium, and what's temp of room, in same time?
Attachments
Yes of course I can do that, but I thought I would take advantage of the knowledge here first in case it was common situation.
That is 22 degrees above ambient. That is not too far off. Pass Labs shoots for I believe 25 degrees above ambient.
There are some bias points on the board that you can check. You will want to do this at the operating temp. Also check:
Differential DC offset - DC between black and red binding post. Should be less than +-10mv or so
absolute DC offset - The DC between one of the binding post and ground should be less than +-100mv
There are two sections to check for bias per XA60.5. Positive output bias and negative output bias. It is good to know how to do this as a basic health check that you can do once in a while. I believe there are little jumpers that you can purchase that have wires that you can tie into your multimeter. Also, it is good to have multimeter leads long enough that you can place the lid on to let the offset stabilize for a couple of minutes after you open it.
There are some bias points on the board that you can check. You will want to do this at the operating temp. Also check:
Differential DC offset - DC between black and red binding post. Should be less than +-10mv or so
absolute DC offset - The DC between one of the binding post and ground should be less than +-100mv
There are two sections to check for bias per XA60.5. Positive output bias and negative output bias. It is good to know how to do this as a basic health check that you can do once in a while. I believe there are little jumpers that you can purchase that have wires that you can tie into your multimeter. Also, it is good to have multimeter leads long enough that you can place the lid on to let the offset stabilize for a couple of minutes after you open it.
Call Pass Labs and talk to Kent. He is in charge of customer service and usually is the guy who answers the phone.