Ayre amplifier to Subwoofer connections

the sub leads should ideally be connected at the amp end of the speaker cables, not at the speaker end. That way the current drawn through those cables by the main speakers, and any consequent voltage drops that might result from interaction of that current with cable impedance, will not affect the signals to the sub.

This is as debatable as the long interconnects vs. long speaker cable argument, as there are pros and cons to each approach. While a technical argument can also be made for connecting the sub the speaker's binding posts, simple logistics makes the strongest argument.

almarg,

A follow up on this.

I connected my r/l speaker outs to the sub, red to speaker positive input and black to chassis ground. The sound was good but not what I expected from the Ayre, the soundstage was compressed into the center and some harshness in instruments such as trumpets etc. As I listened to more music, I definitely felt as though something was not right and started swapping cables. I found that with the either input pulled from the amp, I still got sound from both speakers. Connecting the negative speaker leads both to chassis ground created crosstalk (at about -6b) and so I basically had a very expensive mono system.

So I changed to connecting negative to black speaker input and now everything sounds as it should - which is terrific: great bass, expansive soundstage, space and transparency of instruments (the Ayre is a very musical amp).

Seems to me that the only option is to make sure the sub has no common ground (ground lug on the plug) and connect to the speaker terminals unless I am missing something.

Drew.

Hi Drew,

Not sure what you mean by "with either input pulled from the amp, I still got sound from both speakers." Are there two subs, or one? I assumed there is only one sub, and its amplifier has inputs for both the left and right channel outputs of the main power amp, which it sums together to feed a mono signal into the sub's driver. The left and right main speakers are separately connected to the left and right amp outputs, and I assume are unaffected by whether or how the sub is connected. Correct me if I'm misunderstanding the situation.

If my understanding is correct, my suggestion would be to try connecting sub left red to amp left red; sub right red to amp right red; and one and only one of the two sub amp black inputs to amp chassis (leave the other sub black input unconnected).

Regards,
-- Al

Drew -- A further thought: Try connecting as described in my previous post, but with the sub black terminal connected to preamp chassis, rather than amp chassis.

Regards,
-- Al

Al,

One subwoofer only. What I meant to indicate was when either the left or right input from the DAC is pulled from the Ayre AX7 integrated amp (only one stereo side connected) I hear output from both main speakers (whether or not the sub was on)with the alternate speaker down about 6 - 10 db. When the black leads were removed from the subwoofer amp chassis, there was no crosstalk. Meaning the energy from the balanced negative speaker outs was crossing over and back the negative leads to the main speakers.

So, you are correct and I am having a "duh" moment. When Steve at Ayre suggested grounding the subwoofer speaker connections to chassis ground, he meant on the Ayre, not on the subwoofer. (not a pre-amp chassis as the Ax7 is an integrated that actually doesn't have a pre-amp stage per-se).

I think I get it now and will try the grounding sub negative to the Ayre and not to the subwoofer amp chassis. Although I am still confused about one piece.

Should I do this:

1. Positive speaker outputs on Ayre connected to red speaker inputs on sub.
Negative leads from speaker out to chassis on Ayre - seems like this would ground the mains to chassis as well?

or
2. positive the same
negative from chassis ground on the Ayre to black speaker outputs on sub.?

Drew.