Audio Research D400 mk2

Hi,

Were you able to address the problem with your D400?  I'm an owner as well, was curious.

Thanks

Adam

Yes it's ,fixed. I figured out that when connecting the 2 pairs of speaker cables for my bi-wires speakers one hot lead got loose when moving amp around and was shorting out. it's strange as it would power up and spark but play. at times the left channel (which was shorted) would not play. I tightened all up and no sparks and all is good. this is a Hefty amp and still sounds good after 20 years plus!!

Might be time to have those caps replaced before you run into a serious problem.
20 years is were you start to see them fail. I actual believe D400 mk2 was discontinued in 96 that would make your unit at least 24 years old.

I was in a car wreck years ago .To make a long story short my capacitor(coil ) that charges up for the high tension spark plug outputs had come loose so it wasn’t connected either .It continued  to work even though it wasn’t connected for about a year and then finally stopped working .When the mechanic saw it he showed me what had happened .Tge spark had jumped the gap to the capacitor and completely eaten away the top of the coil,nothing left .It used50,000 volts since it was for the high tension lead on the car .So no surprise rthat the amp still worked even though the speaker wires were not all connected .

Responding to this thread because the OP had Audio Research quote him $2,000 for repairs.

The issue is ARC no longer services this unit and "doesn’t" have replacement caps for the Philips units in the amp that tend to go bad. Last time I talked to ARC they said the D400 mkii was "unserviceable." Not sure if anything has changed with new ownership.

The issue is the caps are direct-soldered to the boards, which makes the amp a PITA to work on. The tech at Pyramid Audio did me a solid by feeling sorry for me because the amp I bought on Ebay (with leaking caps) wasn't working, and he didn’t want me to be left with a very expensive paperweight.

Without the receipt I think it cost me $650 or so for the repair. So, Pyramid Audio is a place that can possibly help, but he wasn’t exactly excited about working on one again lol