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Reverse Phase Preamp with HT Bypass

I am considering purchase of reverse/inverted phase preamp. So, here is the situation as I understand it:

- In order to have the preamp operate properly, the phasing of my speakers need to be reversed. They are bi-wired, so the wiring of the positive (red) versus negative (black) speaker wire needs to be reversed coming from the amp on both posts.

- That means instead of red (positive) speaker wire to red (positive) post, it would now be red (positive) speaker wire to black (negative) post ... is that correct?

Issue: The way my system is set up now with pre/pro (AVR with HT and 2-channel capabilities) going into speakers "in phase" ... everything seems to be working properly. If I reverse the phase - in order to accommodate the new preamp reverse phasing - then what happens when control is returned to the AVR pre/pro via HT bypass? At that point the AVR pre/pro output load is "in phase" going into "reverse phase" speakers in the FL/FR channels of a 5.1 configuration. Will that create a phasing issue? If so, then what is a possible workaround? Please help me understand.
strateahed
zd542
5,339 posts
 
I wouldn't be concerned. The difference between in phase and out of phase, is very small and very difficult to hear. Honestly, it took me a long time using revealing equipment to actually figure out what the difference was. And I could only do it by going back and forth using a source component that has a phase invert button like Brf mentions. Not onlt that, an album can be in or out of phase. And its about a 50/50 split. So even if set your equipment up in phase, the recording itself may be out of phase. That's why I say don't worry about it.
atmasphere's avatar
atmasphere
11,651 posts
 
Phase makes a difference if the recording uses a minimal mic recording technique- either 2 or 3 mics (if the third mic is a center channel).

If more than that are used, valuable phasing information becomes jumbled and the effects of absolute phase is nearly impossible to make out.

Other posters are correct- 50% of all recordings are out-of-phase. That is why a switch on the preamp is nice to have.
strateahed OP
299 posts
 
Sounds like most are confirming mfg comments regarding phase. He basically stated that reversing phase on speakers is necessary to make sure everything works properly with the preamp - in terms of SQ. Then he said don't worry about passive signal with HT bypass engaged ... as this is no big deal for movies or surround sound. Frankly, I did not buy that explanation. That's how the thread ended up here. I'm more comfortable now. Thanks everybody!
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