Sub connection to CARY SLP-05 preamp

Impedance is usually well wihtin range with parallel downstream loads. However, adding to the complexity, I am using the fully balanced modwright 36.5 to drive my subs and mains, and the manufacturer explicitly advises against using RCA and XLR at the same time, because it will create an uneven load on the output transformer. I presume the Cary would have the same issue. So you either use 2 RCA outputs or get a high grade XLR splitter to split your XLR output (only possible if you subs have XLR inputs of course). Purist audio design makes a beautiful XLR splitter, which is an adaptor with no cable.

Al, thanks for explaining.

Grandtech, probaby wise to check with Cary as Marty suggested. Regarding your other question, I'm also with Marty on using speaker level inputs. You want to use EQ with the subs if at all possible which such a setup would preclude you from doing. I am not even sure how you would use the Xover build into the DD-12 on a speaker level signal. I could be wrong here but I believe the Xover works on the line level input. This would make this a complete non-starter, since you need to apply a low pass filter.

I don't know how the DD-12 works, but I presume it has a separe line level input and speaker level input and the EQ and Xover can only be applied to the line level input - I could be completely wrong on this. If this is the case you cannot use the speaker level input, because your subs would run on a full range signal, which would be a complete mess with your mains.

I also would personally never run my mains with a high pass signal out of a relatively low grade Xover build into the sub. (not to mention long runs of cabling from preamp to cabling back into your main power amp.

So to me the only option would be to split the line level signal from the preamp and run parallel into mains and sub, applying EQ in the sub and using the sub xover for low pass filtering. If there are no impedance issues with this approach this would be preferable IMO. Of course, you run your mains at full range in this setup. In my (limited) experience this is not an issue, as long as you use a low crossover point for your subs.

Could very well be. Lack of EQ would still be an issue, but may be even EQ works on speaker level inputs as well.

Marty, I use the NHT X2 as well, but strictly as a low pass filter for my 2 JL113s. The low pass also runs through a SVS sub EQ unit before reaching the subs. My mains run at full range as I am a firm believer of keeping any circuitry (in this case an active high pass filter) out of the mains signal path if you can help it.

If I were to try a high pass filter for mains I would get a Marchand instead of using the NHT x2 (which has very limited slope and cross over frequency options), but I confess that part of that decision would be an irrational suspicion of a $400 device in my mains signal path doing high pass filtering (i.e. the NHT x2).

What we seem to agree on not to use the high pass filter of the sub's Xover for your mains.

Marty, the irrational suspicion of cheap components which a share with many an audiophile, no doubt greatly contributes to the survival of the high end audio industry. Nonetheless I have been very happy with my NHT x2. The reason I bought mine is it was the only Xover I could find that allowed me to integrate discrete left and right channels with the LFE channel for multi channel applications, which is precisely what I am doing. Marchand could custom build me one, but based on your experience I am glad I stayed away from it.