Preamp inverts phase question:

Adampeter- Pick up one of the test CDs I mentioned: (http://www.amazon.com/Stereophile-Test-CD-Vol-1/dp/B0000049XN/ref=sr_1_1?ie=UTF8&s=music&qid=1231724213&sr=8-1) (http://www.amazon.com/Chesky-Records-Sampler-Audiophile-Compact/dp/B000003GF3/ref=sr_1_1?ie=UTF8&s=music&qid=1231724265&sr=1-1) They both have tests that will remove any doubt as to proper phasing on the recording.

Al, remember that when you switch speaker cables you are also affecting wire directionality, or so I've read. In fact, I remember Doug Blackburn writing an essay on polarity suggesting that the primary audible change you hear (if you hear ANYTHING) is the effect of wire directionality rather than polarity. IME, there IS a more pronounced effect from switching speaker wires rather than changing polarity via the preamp's remote. Anyone for listening to some music? Dave

Hmm, some interesting food for thought. I'll say first that I am not in a position to take a position on cable directionality, but I have the following questions and comments:

1)Which end did you switch? Interchanging + and - at the speakers would not change cable directionality -- the electron flow would be in the same direction through each wire, and in the reverse direction only within the speaker.
Interchanging at the amplifier end would reverse the direction of electron flow through each leg of the cable.

2)Was your experience with speaker cables that were basically unshielded wire, or did they incorporate passive networks (a la MIT) that might have been direction sensitive, or did they perhaps have shields (whose physical configuration and grounding might contribute to directionality).

3)In this reference, http://www.6moons.com/industryfeatures/polarity/polarity.html, it is stated that reversing polarity at the amp end can reduce overall distortion, by causing amplifier-generated harmonic distortion to be out of phase with speaker-generated harmonic distortion. I haven't thought that through sufficiently to conclude whether or not it makes any sense, and offhand it is very conceivable to me that it does not, but if so perhaps that was a factor in your findings.

Regards,
-- Al

Al, I switched the cables at the speaker end. The cables I was using at the time were shielded. Doug Blackburn's contention was that the cable-switching affected signal flow directionality of wire and other devices (capacitors, etc.) inside the speakers (soundstage.com/maxdb/maxdb101999.htm) if i understand him correctly. Further, he questions the audibility of polarity-switching per se.

Needless to say, self-proclaimed polarity guru Clark Johnsen ("The Wood Effect") opposes Blackburn's views, to put it mildly. I'm honestly not sure who's right. I only know what I think I hear, and fortunately it's repeatable.

Thanks for the 6moons article. Very interesting. Dave

Will the mono setting on my preamp help me in any way to determine correct phase via listening tests?

Will the mono setting on my preamp help me in any way to determine correct phase via listening tests?

Well, maybe a little bit, by cancelling out the stereo information and simplifying the sounds you are listening to.

As you probably realize, the mono switch makes for a very convenient way of checking relative phase (that the two channels are in phase with each other). In mono mode if relative phase is correct a sharply focused image will be heard centered between the speakers, and if it is incorrect an unfocused diffuse image will be heard.

But I would expect the relevance of the mono switch to assessing absolute phase/polarity to be subtle at most.

Regards,
-- Al