I read some jibber jabber over at HF about the gumby's single-ended outputs gimping the performance big-time.. Any truth to this?

performing meaningful line level matched comparisons between balanced/unbalanced would be a PITA without 2 Gumbys and 2 identical amplifiers side by side.

if you're worried about the extra summing circuit in the path, i assume you can bypass the unbalanced summing circuitry with an XLR to RCA cable that leaves pin 3 floating. this is how i have my DS Gungnir connected, but i would double check with Schiit in the case of the Gumby.

I tried balanced vs. SE. Balanced sounded slightly better, but it wasn't something I would freak out about. For Yggy or Gumby, the proper way might be an Jenson XLR to SE ISOBOX. You really do want both legs of the differential output.

Here's something I don't understand. Basically, what the Jenson Isobox does (and the balanced XLR inputs of amps like BA, Studio and my L-2 amp) is not merely converting XLR to RCA but summing a pair of balanced signal to unbalanced using balanced transformers. Am I correct?

If so, isn't the RCA single-ended output signal of Yggy/Gumby also produced by summing the balanced output signal that would've otherwise gone to XLR? That there's also a pair of balanced transformers inside Yggy that handles this job?

And if so, it's only a matter of whether this "summing balanced to unbalanced" duty is handled inside the DAC right before the output, or between DAC and amp (as in the case of Jensen Isobox), or inside the amp right after the input (as in the case of stock BA/Studio/L-2)?

I remember you saying in another thread that the Jensen Isobox is just as good as the Cinemag balanced input transformers inside BA. Since you're recommending people to use this Isobox, am I safe to assume that Yggy's output balanced transformers (the ones that sum balanced output signal to unbalanced) isn't as good as external Jensen Isobox or Cinemag transformers inside the BA?

And since I'm asking this, did you hear a noticeable improvement by using Jensen Isobox between Yggy and BW? In other words, Yggy XLR output -> Jensen Isobox -> Black Widow sounds superior to Yggy RCA output -> BW?

I can confirm the single leg cable solution is worse sounding than SE summed. I've tried both cable configs on Yggy and will never try that again.

The proper way to do this is summing both positive and negative legs from each XLR channels.

Not being an engineer at all, let alone uber, but this is what I understand....

Balanced and unbalanced line connections are completely different technologies. The purpose of balanced connections is to detect noise collected by the  cable and eliminate it. Summing the +ve and -ve identifies the noise.

Balanced and unbalanced gear can be connected simply by using and adaptor cable (been there, done that, recently) but it is not the right way to do it because the voltages are very different. Hence the availability of converter boxes which convert the voltage as well as the pin-outs.

right?

In an ideal world. Wait... In my ideal world, everything would be balanced.

It is absolutely completely and utterly unnecessary for the short runs of hifi-audio interconnects but, hey, it is such a superior technology. In fact, would it be fair to say that balanced connection is a technology, whereas all that RCA stuff is just an accident?