Preamp inverts phase question:

Benie,
I agree with Almarg. If a pre inverts the signal, it takes either a inverting amp or a switching of the speaker cable polarity to correct it (uninvert it). It is similar to the way positives and negatives work in math. A minus times a plus is a minus, and it takes two minuses to make a plus.

I'm not a tech, are you?
But I have had it explained to me by a very highly skilled Designer and I don't mean someone into DIY.

As far as a article about: Google is your friend!

Can you kindly offer either a technical explanation saying how I might be incorrect, or a link that would provide one?
I am not talking about, Recording or Speakers!!!

Since you asked, I have both Bachelor's and Master's Degrees in Electrical Engineering, and more than 30 years experience as an electronics circuit designer and manager (although not in audio). I also have close to 30 years experience as an audiophile, and I am widely read on the subject, including high end publications (TAS, Stereophile, etc.), mainstream publications, the Journal of the Audio Engineering Society, etc.

I have never in all that time encountered the claim you have made, that inverting preamps work best with non-inverting power amps, and vice versa. By that logic, every properly set up system should invert absolute phase/polarity overall. That conflicts with everything that has been written indicating that maintaining absolute phase can be important in some systems with some recordings, to a subtle degree. You can start with the papers that Jea linked to.

I understand that you are not talking about the recording or speakers. You appear to be saying that somehow a preamp/power amp combination will function best together if the combination of the two components is inverting. As I say, in all of my experience that I cited above, I have never encountered such a claim. Likewise, I have never encountered any claim that having a combination that is non-inverting is necessarily better, either, other than the fact that it maintains the polarity of the recording without having to interchange speaker connections. So I don't think that asking me to provide a link that will "prove a negative," so to speak, is quite a fair question. Questions that have no basis tend not to be discussed.

Regards,
-- Al

I agree with Almarg and Zargon. In my case, I have an American pre and a German amp. To run them in balanced mode while preserving polarity, I bought an interconnect that had the XLR pins reversed at the factory (2 to 3 and 3 to 2). That works very well, and I have not had to reverse speaker cables or otherwise fuss with the system. The cable manufacturer, by the way, was quite familiar with my problem and how to correct it, and reversed the XLR pins at no additional charge.

I concur with both Almarg and Zargon, Bernie is incorrect. Once the phase is inverted, it does not magically 'uninvert' on it's own. If the preamp inverts and the amp inverts, then you are back to absolute phase. One more option could be an inverted source. An inverted source with an inverted preamp and a non-inverting amp would also produce absolute phase.

To make it simple, think of absolute phase as a '+' and inverted phase as a '-' . 2 X '-' = '+' , 1 or 3 X '-' = '-' .
You can simply change the '-' to a '+' by switching + and - on your amp terminals, no big deal.
Of course since 50% of recordings are recorded out of absolute phase, it really shouldn't matter at all.

Cheers,
John

Maybe I should just buy an absolute polarity checker?