Ayre amplifier to Subwoofer connections


I am trying this question again with a more specific title to try to get responses . . .

I am intending to hook an Ayre, fully balanced amplifier to a subwoofer via the high level (speaker) inputs. Ayre has told me NOT to connect negative to black but to chassis ground. A balanced amplifier cannot be connected to anything with a common ground.

The subwoofer amplifier manufacterer (O-Audio) says the plate amplifier has no common ground by virtue of the fact that it only connects 2 prongs to the outlet.

I have also heard that other audiogoner's have connected Ayres to subs via the red and black speaker connections without a problem. How have you accomplished this?

Can anyone explain to me in more detail what is up with this technically and what connections I should be using.

Additionally, can you tell me the pros and cons of connecting the speaker leads to the sub from the speakers vs the amp. Does it have to do with length, noise, etc?

thanks to everyone in advance!
drewh1
Ouch! Yes, by all means what was meant was sub black to amp chassis, not vice versa. Keep in mind that with a fully balanced amp, both the red output and the black output of the amp have signals on them (in fact, the same signal except with opposite polarity, as you now appear to realize). When you connected both of the amp's black outputs to sub chassis, you were connecting two different amp output signals together, a definite no no!

I don't quite follow the two alternatives you listed at the end of your post, but let me re-state how I envision the connections should be made:

-- Left main speaker red to Ayre left channel red.
-- Left main speaker black to Ayre left channel black.
-- Right main speaker red to Ayre right channel red.
-- Right main speaker black to Ayre right channel black.
-- Sub left channel red to Ayre left channel red.
-- Sub right channel red to Ayre right channel red.
-- One or both of the two black terminals on the sub to the chassis of the Ayre. I suspect that it won't make any difference whether you connect both of them, or only one of them, since they are most probably connected directly together within the sub's amp.

Regards,
-- Al
Al,

I get it and appreciate your help - now I am going to leave things as they are and enjoy it.

drew.
This is an interesting and timely topic as I just today picked up an AX-7 to play around with. I connected my REL to it the way I normally would, with the one black lead connected to one channel's "-" terminal. Drewh1, did Ayre suggest what to use for chassis ground on the unit? There are no obvious screws on the back to use.

(In case anyone at Ayre is reading this, the Cardas binding posts are not ideal when you are connecting a subwoofer this way because you end up tightening down for the terminal with the subwoofer lead and then it's not tight enough on the other pole.)

For subwoofers that only offer line level connection, such as the JL Audio subs, how would you connect them to the Ax-7, which has no pre out -- through the tape out?
I connected my REL to it the way I normally would, with the one black lead connected to one channel's "-" terminal.

Drubin -- What model REL is it? And does it have a 3-prong power cord? If so, you definitely don't want to do that. For the reasons I explained above, and also note the cautions on page 5 of the AX7 manual:

http://www.ayre.com/pdf/Ayre_AX7e_Manual.pdf

Regards,
-- Al
It's an R-205 and, yes, it uses a 3-prong power cord.

I've lifted the ground. Sound seems to be the same either way.