How to wire audionics cc-2 in mono mode

... how is circuit complete without a ground

The two black output terminals of the amp are almost certainly connected directly together within the amp, as well as to the amp’s circuit ground (to which the ground sleeves of the RCA connectors are undoubtedly also connected, by the way).

In bridged mono mode the red output terminals of the amp would both have full amplitude signals on them, with the polarity of the signal on channel B being the inverse of the polarity of the signal on channel A. The speaker won’t "know" that neither signal corresponds to the circuit ground of the amp. And the current supplied by each channel of the amp through the red terminal of that channel would be returned to the red terminal of the other channel, and from there through the output stage of that channel to the amp’s circuit ground.

From the perspective of each amplifier channel, a given output voltage will result in it having to supply twice as much current as it would have to supply under the same conditions in stereo mode, as a result the other channel of the amp supplying an equal and opposite voltage to the other terminal of the speaker. In effect the doubled current for a given output voltage results in each channel of the amp "seeing" the speaker’s impedance divided by two, which is why the amp is not intended to be used in bridged mono mode with speakers having less than an 8 ohm nominal impedance.

Regards,
-- Al

Thank you  Almarg for explaining I can't wait to get them back from the shop .thank you all

I'm thinking of picking up another CC-2 to run both bridged into my Martin Logan ESL speakers who's nominal impedance is 6 ohms. Can this work if I'm carful with the volume?

So without any feedback on the warning I found about not using CC-2s in bridge mode with speakers less than 8 ohms, I went ahead and bought a second CC-2 on eBay for $61.56 to my door. I figured at the very least I could use it for spare parts. But it sounds great so I looked up bridge-mode wiring. I don't remember the source but it's pretty simple. On each amp use the Channel A input from the preamp, then wire each speaker from the Channel A positive to the Channel B negative. Don't forget to throw the bridge switch to Mono. I currently have them stacked one above the other but I really need to re-organize the components on my shelves so they are side by side. Obviously the previous arrangement causes the amp above to run much hotter than the beneath. So how do they sound driving my 6 ohm Martin Logan EM ESLs?  ONE WORD - W O N D E R F U L L Running them up to 95db via an old Realistic SPL Meter, there is no sign of any problems with amps or speakers. Love these little amps. BTW my Apt 1 amp (below my Apt Holman Preamp) drives my two 12" subwoofers for the bottom two or three octaves with bass you can feel in your gut. (variable cross-over point) In the meantime I'm loving my 1980's system (excepting the ESLs and an Oppo BDP-95 multi-disc player) I'm guessing no one will read this since my past post when completely unanswered.