Newbie question about reversing Phase??

That's all you have to do. Just be sure your amp doesn't reverse phase as well (if it does, you don't have to do anything).

I don't know why but every product,whether amp or pre says; do the reversing at the speaker.--I have an amp in one system and a pre in a different system that do this.--Each manual says do it at the speaker terminal.

Newbie:
There is something called "absolute phase". If a single speaker is wired out of phase, it's initial excursion is back, not forward. You can feel this by putting your finger on the speaker cone and feel if it pushes out or in when, for instance, a bass drum kicks. All the speakers can be in phase with each other but the whole system can be 180 degrees out of phase in reference to the original recording. Even a turntable cartrige can be wired out of phase and screw everything up from the start.
So begin with a single speaker and make sure it's not 180 degrees out of phase and reference the other speakers to it. Also some speakers can be mismarked at the terminals. A simple test is to take a 9 volt transister battery and, using a test lead with aligater clips, connect the positive of the battery to the positive of the speaker. With your finger on the diaphragm, feel the excursion as you touch the negative aligater clip to the negative lead on the speaker. If it is correctly wired the diaphragm will push out when you touch the terminal with the aligater clip. This will tell you if positive is really positive with respect to the internal speaker wiring. To be sure, test all the speakers in our system. Finally, rocket science explained!

Dc2, there was a previous discussion of this. I had always thought as you do that the contact with direct current should be an outward push of the driver. Now I am less certain. Consider the microphone and the initial impulse of a horn. The microphone moves backward. If this electronic impulse is a positive pulse the driver would be pushed outward, but if the impulse is negative, it would pull the diaphram backward. All would depend on the microphone being hooked up out of phase. I wonder if there is any consistency to this.

Some speaker manufacturers (JBL is one) use opposite polarity...plus voltage pulls the cone IN.

There is little consistency from recording mics, mixing consoles, amplifiers and speakers, so the likelyhood of getting it "right" is small. Fortunately only a few golden ears can detect the effect.

Also, it is improbable that a preamp with phono will maintain absolute polarity throughout or between the phono and non-phono inputs.

I have a little unit for inverting polarity on phono but never use it. Most often, however, you can hear polarity differences on LPs. With purist digital players I no longer have the easy choice of polarity on digital. My old parafeed Exemplar preamp could easily have had a polarity switch by just reversing the output side of the transformer.

Which way the speaker goes is based on patents and not theory.JBL's excuse was that they were using the current theory of direction when the movement was "In" during the positive cycle. Actually that had already been patented using electron flow with the movement being "Outwards" during the positive cycle. JBL now "Phase Corrects", since sometime in the '90's, all of it's systems at the output of it's crossovers.

To: eldartford, Having worked with professional audio since the ’60’s I can assure you that the issue of polarity is not that bad. Until the late ’80’s all of Europe was pin 2 positive on any device that used an XLR balanced connector, America was mostly standardized on pin 3,than in the late ’80’s it was finally standardized as pin 2 representing an inward deflection on a microphone diaphragm resulting in a positive going signal with the speaker pushing outward with that same positive going signal. Now with that in mind you can see where when (phase timing), is more useful than which direction (polarity), the signal goes, when listening to music.
However you do bring up a very important point. There are tremendous differences in the quality of electronics. Some are for creative purposes but many are the realities of budgets. Just as in consumer electronics not all studio"s have the "best" or even close to best. It started with TEAC in the '70's bringing WAY down the cost and quite often the quality of recording studio's. Mostly gone are the traditional go to studios of the audiophile. Fewer symphonic recordings are being done with simple but high quality microphone systems. Most pop albums suffer from saturation distortion due to the "Loudness Wars". Many home studio's use "Monitor Speakers" that you wouldn't put in a dog house. Paying attention to the label and producers make a bigger differences than absolute phase, as long as it matches

Which preamp?