Does the Audio Research PH-3 Invert Polarity?

Mine doesn't.

Doesn't look like it based upon the schematics.

Thanks guys. Usually ARC and other manufacturers let you know whether a piece of gear inverts phase or not. I see nothing that comes with the PH-3SE that mentions phase.

Don't most good preamps have a polarity reversal swith?Seems like an overpriced phono preamp that doesn't allow you to adjust ANYTHING!? Like you have to get inside and change resistors just to adjust the input imped!!.(And this is from a hugh ARC fan). I haven't really done analog for a long time, so is this typical? I think i would look for a phono stage that has a allot more to offer. Just some idle comments.:)

I am quite aware that every gain stage changes the polarity. However, I wasn't sure how many gain stages the PH-3SE has. And most preamps do state whether they invert phase or not.

As for 6550C complaining about the ARC PH-3, many phono sections require the insertion of resistors to change loading. Others require you to remove the top cover and flip a bunch of switches. ARC just requires you to solder them in place as obviously they feel any other means is a comprimise in sound quality.

Having owned a McIntosh C2300 preamp, I am a little leary of the swiss army knife approach to preamps. Yes, it was cool to switch cartridge loading from your seat with the remote, but I was not fond of the C2300 in general and the phono section in particular. I got rid of this preamp because I just didn't think it sounded very good. I can tell you the ARC PH-3SE is a way better phono preamp than the C2300. I am using it with an ARC LS-17 and I find the combination to be outstanding so far.

And lastly, I don't know of many stand alone phono stages that allow you to flip phase. 6550 stated that he would look for a phono stage that has a lot more to offer. That is fine and I understand that comment. However, I am fine with the trade-offs that the ARC PH-3SE has. I will gladly make those trade-offs as long as it sounds great and it does. I paid $1100 from the original owner and it came with everything it did the day it was shipped from ARC and it is in great shape. Plus it has 3 Amperex 7308 gold pin tubes. I feel it offers outstanding value and sound quality for the money I paid.

The reason for invert is EVERY stage inverts.

Actually every stage with voltage gain inverts. To have a non-inverting preamp with gain you need at least two stages of voltage gain.. an inversion and another inversion puts you back to non-inverted. In almost all cases you can get enough gain from a single stage so CJ and others choose a single gain stage followed by a buffer stage that does not invert. Why add a buffer? By it's nature a voltage gain stage has an output impedance that is too high so the buffer lowers the output impedance, has unity gain, and does not invert. Net result.. voltage gain inversion followed by buffer non-inversion = inversion.

Since you can correct for the inversion by reversing the speaker cables why add another gain stage that isn't needed?

Don't most good preamps have a polarity reversal switch?

In a perfect world they would but adding that feature means some additional circuitry that some feel degrades performance.

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"Since you can correct for the inversion by reversing the speaker cables ..."

True enough, but since so many disks/tapes were recorded in inverted polarity, this gets to be a terminal pain in the butt. I did it for over a year, wearing out banana plugs in the process, but getting an Aesthetix Calypso (with polarity switching available via remote) was a godsend. If your speakers are really polarity-coherent, you NEED a better way to switch polarity, IMHO. Dave

For those interested, the VAS Citation I pre amp has a phase switch. I've found it useful and have been very pleased with the unit. I did have a ARC PH3 initially and when I compared it to the VAS, it was no contest, VAS was much better.

Looking at the schematic, there is a FET gain stage followed by a cascoded tube gain stage, followed by a cathode follower output. Ergo, two gain stages means it does not invert phase.