KJF Audio MA-01 Review (Multi-channel Amplifier)

[Robbie010]

Firthermore……

As an additional test, I plugged the RCA out from Wiim directly in to the channel on the MA-01 running the midrange compression horn and the background noise was massively reduced without the DSP unit inline.

Dag nammit, surely it must be a grounding issue causing this?

 

[levimax]

Firthermore……

As an additional test, I plugged the RCA out from Wiim directly in to the channel on the MA-01 running the midrange compression horn and the background noise was massively reduced without the DSP unit inline.

Dag nammit, surely it must be a grounding issue causing this?

Sounds like the DSP to me. To confirm you need to "short" the RCA inputs on the DSP (with a shorting plug that connects the RCA plug center to RCA plug ground or something similar you make from RCA cables and a piece of wire) and hook the DSP up to the amp and turn it on. If you hear hiss with shorted inputs it is the DSP which was not designed to be used with such efficient speakers. If it is quiet then your problem lies elsewhere. Previously you mentioned the amp made noise with the inputs disconnected which is not unusual, in order to check a component for noise you need to short the inputs otherwise they can pick up noise from many different sources.

 

[Robbie010]

Just a quick update on this, after more research and reaching out to Stefan at KJF Audio, I think we have found a solution.

What is required is a bespoke RCA to XLR cable connect as follows:

RCA Signal (Tip) to Pin 2
RCA Ground to Pin 3 & Ground
RCA Shield to Pin 1 & Ground


I will update this thread for posterity when new cables are installed.

 

[manisandher]

... and reaching out to Stefan at KJF Audio...

Stefan is local and has done a number of things for me, including the acoustic treatment of my room. Totally excellent guy.

Mani.