Hegel Design Flaw?

Almarg,

I connected the REL and the H20 together. The ground wire was attached to the left channel. The problem was the sound coming out of the right speaker. So, the REL could not have caused this problem.

Even supposing the REL may have been the culprit in some hidden way, why would the dealer or Hegel not ask about sub connections and make appropriate suggestions instead of saying I needed to dismantle my system? Surely, this problem would have shown up earlier with thousands of Hegel products out there, some of which must surely be attached to REL subs. I think it is clear that the REL was a moot point.

08-25-15: Sabai
I connected the REL and the H20 together. The ground wire was attached to the left channel. The problem was the sound coming out of the right speaker. So, the REL could not have caused this problem.

Agreed.

Even supposing the REL may have been the culprit in some hidden way, why would the dealer or Hegel not ask about sub connections and make appropriate suggestions instead of saying I needed to dismantle my system?

Yes, the (non-)support they provided sounds like it was very poor, as I said earlier.

Surely, this problem would have shown up earlier with thousands of Hegel products out there, some of which must surely be attached to REL subs.

Several manuals I've seen for various REL subs state that when the sub is connected to the outputs of a fully balanced stereo amp, and if the amp does not provide a circuit ground terminal (such as some of the Pass amps do, for example), the ground wire should be connected to a chassis screw, not to a negative output terminal.

I would expect doing that to work well in at least most cases, and for that matter you may want to try it with your S-30, as it may provide better sonics than connecting the ground wire to a negative output terminal (that has a signal on it, and a signal which corresponds to just one channel). If and when you try that, keep in mind that you may have to re-tweak the level control on the sub.

Regards,
-- Al

Almarg,

Thank you very much for this helpful suggestion. I will give it a try.

Knghifi,

The Atma-Sphere S-30 drives the Raidho C1.1s with more than enough headroom thanks to Paul Speltz Zero-Autotransformers.

The Atma-Sphere S-30 drives the Raidho C1.1s with more than enough headroom thanks to Paul Speltz Zero-Autotransformers.

I never understood why adding a transformer to an OTL just to make it work. Either buy a bigger OTL or different type of amp IMO.

I auditioned Atma-Sphere M-60 with Paul Speltz Zero-Autotransformer driving Acoustic Zen Crescendo. It sounds fantastic on less demanding material but overall had trouble controlling the speaker. Acoustic Zen Crescendo is much easier to drive than C1.1.