Wiring SSB01 buffers for balanced/XLR + questions

[ssmith]

I've ordered a set of 4 SSB01 boards. They will be be placed at the input of Class D monoblocks I'm making -- the Class D units (Anaview AMS0100-2300) have a very low input impedance so I wanted to make them more universal. They will be fed balanced XLRs from a DAC.

I have a few questions:

1) I need 4 SSB01 boards for stereo (2 for left and two for right). Is it correct that the boards should be built identically, with, at the inputs and outputs, the '+' signal being sent though one board, the '-' though the other board, and the ground attached to both?

2) I may also add signal capacitors on the +/- of the balanced inputs. Would it be a good idea to protect the amp with input capacitors -- and if so should the input capacitors be put between the XLR-in socket and the SSB01's, or between the SSB01's and the amp module?

3) Is there any downside of having an input impedance of 1Mohm (SSB01), being fed by a DAC with an output impedance of 200 ohms?

many thanks!

[peranders]

1 Yes

2 It could be a better idea to have the cap to the SSB01 input since you then can have smaller caps. It could be better to have the caps between the buffers and the amps. It depends of switch on/off transients.

3 No, but it depends of how the DAC output is designed.

[ssmith]

Many thanks for the reply!

for the caps, I'm not too worried about size as I have a bunch of different types and values to experiment with, including some old Blackgate NH 150uf/350v which I've tried before as signal caps and have been really impressed with. The value is way too high for their intended purpose but last time I did a comparison (with some Audyn caps and Sonicaps of around 2uf) the result was better with the BGs. I'll experiment again and try different placements...

The dac I have now is a Teac UD-301 which I assume has a fairly standard buffered output. I'll use XLR balanced outs with cables of about 2.3-3 metres.

Thanks again and will keep you posted on the build and the result!