DC offset question.

[farflungstar]

This is my worry. I really can't say for absolutely sure what caused it (the techie said it was DC at the input) - but what other equipment did it? The problem came up (or was very apparent) when I bought that ill fated CDP and connected it direct to the amp using its inbuilt volume. That was returned but I cannot be 100% sure it was the cause.

I checked the DC at the outputs of the truth pre after the techie told me about the DC - one channel (at the 200m setting) was 00.2 the other 01.7 - but had I checked it at the 2000 setting I don't know what that would have been. For this reason I contacted the maker (who said it was negligible and not likely to cause any issue) and adjusted the input buffers and output buffers to 0 on both channels using the 200m setting on the meter. In theory there is no DC in the circuit except perhaps the anomoly of bad probe contacts on the outputs when measuring.

The truth is never switched off and I never connect or disconnect stuff when things are switched on. The only components are the cart, Vida, hashimoto, truth, ref 75, Tannoys.

Is there a possibility that the small input tubes in the 75 could have an effect? It was soak tested using them at the centre without a problem but I have a brand new set of power and signal tubes.

It's silly but I still haven't switched the amp on - I just dare not.

The truth has caused no problems with the Hiraga amp but of course it's a different animal to the ARC.

One more doubt - I bought the 75 second hand, and the CDP shortly afterwards - there is the possibility that the ref 75 was faulty when I bought it - this is the problem - so manyy variables I feel like dumping the lot.

I just remeasured the pre outputs having rigged up an RCA plug to the meter probes. Right 000 left -000 - set at 2000m. At 200m I get right 00.4 left -00.2.

I have replaced ALL tubes with new.

Should I try it?