Is it possible to down-mix stereo outs to mono amp

Hi Mofi,

Yes, if the source is switched to mono using a y-adapter would not cause any problems. But in this particular situation, at least, if the source is outputting mono just hooking up one of the outputs should work just as well. (In other situations, where sonics are more critical, there could conceivably be some benefit to summing the two nominally identical signals together).

BTW, the issue I cited with summing a stereo pair of signals together via a y-adapter has no relation to the power supply quality. It just relates to the output impedance of the output stage of the DAC, and to how robustly that output stage is designed. And in most cases it would probably work fine, with no effects on long-term reliability. But as I said, shorting two outputs together is poor practice at best, IMO, and I would expect that with at least a few designs it would eventually cause problems.

Arguably I could be over-reacting a bit, given that many people do that kind of thing without issue, but shorting together two outputs that are producing different signals is offensive to my EE sensibilities :-)

Best regards,
-- Al

Right you are Al, your original post wasn't up yet when I made mine. As for sound quality loss from a Y-adaptor, with the Grundig being the final link would that really be of much concern?

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09-22-15: Mofimadness
Al...ZD's suggestion doesn't address the OP's hook up question. It is software based, BUT, if the source in question can be switched to mono, then would a "Y" adapter work?"

If the OP uses software to convert stereo to mono, there is no hook up question. The same exact signal goes to the R & L channels. If actual components like a source or preamp has the ability co convert the signal to mono, its the same thing, as well. If you just have 1 mono amp, all you need to do is plug one of the channels into the amp. You don't need to combine the two.

09-22-15: Zd542
"If the OP uses software to convert stereo to mono, there is no hook up question."

Yes, there is a hook up question. Just because the signal is converted from stereo to mono "at the source", how would the OP get that from his DAC to the Grundig? You never addressed that in your original comment.

At the risk of sounding wishy-washy, Almarg is right - it's better to work into a load for any output - otherwise, you're basically shorting the left and right channels to each other.