OK, it's definitely a DC offset issue. Measuring the balanced output of my interface while playing back that problematic bloc party track, I get a whopping 3.5v of DC:
That's *really* bad - I did a quick scan of some of my library and the worst I could find otherwise was around 0.1vdc on some amateur soundcloud stuff. My best guess is the Topping is either going into DC detection/protection directly, or the DC offset in the signal is causing the amplifier to overload, and the Topping then goes into overload protection. I suppose that's nicer than the Topping just allowing it to happen unnoticed until the front end fries itself. Some clarification from Topping on this would be great.
So, warning: if you're lucky enough to have an interface with a DC-coupled output, (most high end converters, a lot of professional/recording interfaces), take note of what you're playing. If you find the Topping switching itself off and not coming back on until you stop playback - it's probably DC in your source material. Anyone brave enough to play back the Bloc Party track I linked on the last page should be able to recreate this without issue, it does seem to at least be harmless as it goes into protection (at least for now). And to the mastering engineer of this Bloc Party album, which peaked at #3 in UK Albums Charts at one point: give me some of that crack rock you were smoking
Also happens in D30pro?
I don't know what you mean.
Can't you just use the balanced trs outputs?
Circuit topologically, and actually, single ended. From line, and balanced signaling, it's effectively balanced.
A30 Pro has no PRE but only pass through, so RCA in TRS out or XLR in RCA out can't work. TRS to RCA cable might work but it might introduce noise or distortion, TRS is balanced RCA is unbalanced. So there's no telling if this will work properly. Voltage-wise it'll drop half since RCA is not balanced so no issue there. But overall I'm not sure your set-up would be the best idea. You can try though..
You can use either RCA input or XLR input, and all headphone outputs will work in either case. No problems there.
2V single ended vs 4V balanced input will make quite the difference, for HE6 a balanced DAC wouldn't be a bad idea..
Do you have any recommendations? Not wanting to pay 400$ just for a dac.
Have you already ordered the A30 Pro? If yes, just try D50s and high gain on A30. Might suffice. If you need more, check out SMSL SU-8. Or Grace SDAC balanced on drop. Geshelli J2 should also be good... I see it's not orderable right now though.
Yes, the idea was that..TRS Cables to RCA, but yeah that's the problem, TRS is balance and RCA is not, so not sure if that could cause troubles.
Would make more sense yeah. The source is the DX7 after all. No sense to use the passive TRS out from the A30 Pro, can only cause issues and at best won't make anything better.
