AVI ADM 40 balanced input.

[oldric_naubhoff]

like I said a few post before; RCA is good for short run. if you dig into the history of the connection on wiki you'll see that RCA used it to make internal connections for their phonographs. RCA has never been meant to be a long run interconnect. AFAIK 1m is border length. take look at pro audio. there's miles of cabling lying around on each stage and yet you hear no hum, no hiss through the speakers. this is because balanced interconnects cancel common mode interference. OK you could have RCA with shielding, but it will never be as efficient as balanced interconnects.

I use studio monitors with studio XLR interconnects and an audio interface. My speakers hum and hiss.

The hum greatly diminishes when the preamp section is active and the hiss is induced by the preamp (I am almost certain).

:?

but to be honest I was always quite suspicious about balace-ness )) of budget gear... I'd like to know how is the balanced signal managed in your pre...

 

[Phileas]

and I don't think it's about just fashion.

Tradition?

 

[oldric_naubhoff]

I use studio monitors with studio XLR interconnects and an audio interface. My speakers hum and hiss.

The hum greatly diminishes when the preamp section is active and the hiss is induced by the preamp (I am almost certain).

I remembered something this morning and decided to tell you. maybe it'll be of interest to you. I had similar problems with hissssing of my previous amp. it was Teac AGH600. hissing was easily audible from at least 1m (Dynaudio Focus 110). but the SNR ratio per spec sheet go up to 110 dB. very good. then it was replaced by Pathos. 90dB SNR. much poorer result. but the hissing disappeared almost completely. you have to have your ear up to the tweeter to hear anything. and Pathos uses tubes in its pre section which are said to be more "noisy".

I believe that if you change your pre for something more robust you'll appreciate the difference.

 

[Overdose]

It's in the pipeline.

 

[oldric_naubhoff]

It's in the pipeline.

and as far as the hum is concerned. this AFAIK is symptom of poorly designed power supply. a decent one should filter out mains interference. is your DAC/pre USB powered maybe? do you know if it has isolation from computer power supply noise?