Just got a new power amp

PS Audio S300 is not fully balanced. "Bridged" output might suggest that, but it isn't a bridge of two amps but 4 Mosfet bridge to flip speaker direction between V+ and GND, since output is single voltage supplied.  Some class D modules, like Hypex, use dual +/- supply and only 2 output Mosfets.  S300 is based on 300AS1 Icepower module, almost identical to 200ASC (in my Rowland 102), but  with stronger output Mosfets.  Both my amps Benchmark AHB2 and Rowland 102  don't have RCA inputs.  

The most important thing is what you can hear.  Some features of XLR, like higher noise rejection or locking connectors with female input side (pins recessed - not exposed) might be very important in a large studio - not so much at home.

PS: Both speaker terminals have about 30V DC (half of supply) on them - do not short  either to GND.

 

kijanki

PS Audio S300 is not fully balanced ...

You might want to check the specs of the amplifier here. They certainly reflect those of a balanced amp.

@cleeds   I don't see anything in specs showing fully balanced operation.  

Look at page 5, Fig 1  300AS1 datasheet  showing block diagram.  After balanced input, there is only one path (one amplifier).

https://shop.icepoweraudio.com/wp-content/uploads/2023/02/ICEpower300AS1_Datasheet_2_2.pdf

kijanki

I don't see anything in specs showing fully balanced operation.  

Look here. Big clue:

Input impedance 

Unbalanced 50KΩ
Balanced 100KΩ

After balanced input, there is only one path (one amplifier).

So? You seem to not understand how a balanced amp works.

This amp looks like it's differentially balanced, a perfectly valid approach. This is taken from the data sheet you provided:

Input Stage
The balanced input section provides signal buffering and anti-aliasing filtering. The balanced configuration helps to avoid hum and noise pick- up from poorly shielded cables. An unbalanced input can be obtained by applying a short circuit
between Signal In- and Signal GND ...

Output Stage
The output stage is a full bridge topology with a 2nd order filter, thus the power output on the terminals Vo+ and Vo- is balanced ...
Warning: The balanced speaker outputs are both “hot”  (emphasis added)

@cleeds  It is amplifier with balanced input and not the "Fully Balanced Amplifier".  "Fully Balanced Amplifier" term refers to amplifier consisting of balanced input followed by two separate amplifiers - each driving one terminal of the speaker.