ScooterMcTav
I know less than I think
I realize that 17 year old pieces are not as vintage as we normally see here, but have been stumped with a problem with my used Arcam A85.
First off, I really like the piece. Not the most powerful integrated I own, but it has a lovely balance of solid sound, and detail without becoming glaring.
This integrated has an internal pre-power amp switch which can be defeated, then a device such as an EQ or DSP could be inserted. When I first received the unit, this is exactly what I did with a vintage Realistic EQ.
However, when i turned on the EQ, it issued a "pop" which then turned off the speaker relays, and gave me the message "DC Offset - Check Connections". This suggests the EQ had some DC in its outputs that was triggering a protection mechanism in the amp.
So I proceeded to leave the EQ on, and things worked relatively OK for a while.
Then, someone turned off the amp by using its main power button - when I powered it back on, the sound was somewhat muffled, and the volume control didn't work. So I turned it off and on again, and another pop, speaker relays cut out, and the DC Offset message returned.
Unplugging the amp for a few minutes seems to reset everything appropriately, and the error does not occur for a bit.
This seems to be happening intermittently, and now I do not have anything hooked between the pre/power sections. The previous owner did use a DSP between the pre and power sections, so my thoughts were:
a) There is a problem with the output of the EQ - be that it is too hot, or is throwing some DC into the mix
b) There could be a problem with the internal switch contacts, causing some issues when using the internal jumpers
c) There is a yet undiagnosed problem with the speaker wires, or a loose wire somewhere
d) There is an actual problem with the speakers themselves, though I cannot hear anything that would suggest this
Curious if anyone else has had the same issues, and/or if they were able to solve them. I did read online that there appears to have been a post-manufacturing mod made to lower the unit's sensitivity to the DC Offset error, but can't find anything other than this simple high level information.
First off, I really like the piece. Not the most powerful integrated I own, but it has a lovely balance of solid sound, and detail without becoming glaring.
This integrated has an internal pre-power amp switch which can be defeated, then a device such as an EQ or DSP could be inserted. When I first received the unit, this is exactly what I did with a vintage Realistic EQ.
However, when i turned on the EQ, it issued a "pop" which then turned off the speaker relays, and gave me the message "DC Offset - Check Connections". This suggests the EQ had some DC in its outputs that was triggering a protection mechanism in the amp.
So I proceeded to leave the EQ on, and things worked relatively OK for a while.
Then, someone turned off the amp by using its main power button - when I powered it back on, the sound was somewhat muffled, and the volume control didn't work. So I turned it off and on again, and another pop, speaker relays cut out, and the DC Offset message returned.
Unplugging the amp for a few minutes seems to reset everything appropriately, and the error does not occur for a bit.
This seems to be happening intermittently, and now I do not have anything hooked between the pre/power sections. The previous owner did use a DSP between the pre and power sections, so my thoughts were:
a) There is a problem with the output of the EQ - be that it is too hot, or is throwing some DC into the mix
b) There could be a problem with the internal switch contacts, causing some issues when using the internal jumpers
c) There is a yet undiagnosed problem with the speaker wires, or a loose wire somewhere
d) There is an actual problem with the speakers themselves, though I cannot hear anything that would suggest this
Curious if anyone else has had the same issues, and/or if they were able to solve them. I did read online that there appears to have been a post-manufacturing mod made to lower the unit's sensitivity to the DC Offset error, but can't find anything other than this simple high level information.