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Impact of phase inversion by preamp

This will be my first post on this forum so I thought I’d pose a question I’ve always wondered about.  I have a Conrad Johnson Premier 18LS preamp that I’ve been extremely happy with since first acquiring it some years ago.  This is a solid state single ended, single stage design that inverts the phase of the input signal at the output.  The manual states that you should reverse the connections to the speakers to account for this.  Obviously this is easily done but I really can’t see how it would really matter as long as things are connected consistently between the left and right channels.  I’d be interested to hear what others have to say on this subject.
ligjo
ligjo OP
7 posts
 
Wow!  Thanks rodman.
rodman99999
5,984 posts
 
Hopefully, you can find something helpful/enlightening, in all that.  
boxer12
8,654 posts
 
One of the things I like about the Jeff Rowland preamps is the phase switch. I use it all the time & sometimes it makes a pretty big difference. CD's seem to be more prone to be recorded out of phase than analog LP's. Just my experience.  
merosen
45 posts
 
I have fully balanced system. Tonearm/cartridge, cd, Atmas Sphere preamp and mono blocks . The preamp has an inversion switch. One effect Ive notice when experimenting with the switch is you can get an out of phase effect that gives you an ultra wide soundstage (sort of unbelievable) and a deadened hole in the middle.
bdp24's avatar
bdp24
9,420 posts
 

This subject has been brought up a number of times, and every time it is once again pointed out that many (most?) loudspeakers have their two or three drivers wired in opposing polarities. As an example, the midrange driver will be opposite the woofer and tweeter (Wilson's, I believe). Reversing the polarity at the pre-amp will result in each driver then being opposite of what it was. What remains constant is that different frequency bands are being reproduced by drivers in polarities opposite each other. Which frequency bands do you want in "correct" polarity? Wire your speakers (or flip your pre-amp control) so as to achieve that.

But as almarg said above, many recordings are themselves already of mixed-polarity, so what does it matter?! If you play a single-polarity recording through a single-polarity loudspeaker, phase reversal should be more audible than in the above scenario. Phase reversal of the Sheffield direct-to-disk LP's is more audible than of "normal" recordings, and many of the Sheffield's are themselves in reverse polarity (a snare drum strike creates rarefaction, not compression). Sheffield recommended the playback system polarity be reversed when playing their LP's.

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