Nearly all of the Balanced Audio Technology pre-amps have polarity inversion and feature a button on the remote for that as well. I know the VK-3i does NOT have the feature, but it's my understanding that every other pre-amp in their line does have switchable polarity (phase).
My older Klyne SK-5 preamp has a polarity invert position on the front panel. I don't know if the current models ( System 6 and System 7 ) have retained it.
The excellent Lavry DAC 10 has a front panel polarity inversion capability.
Guys, thanks, I appreciate the responses so far. I forgot to mention that I'm looking for RCA outputs as well.
I think some of the Audio Research preamps have the polarity invert feature, but I can't recall which models.
That feature is available on Aesthetix Callisto with remote.
My Bryston BP26 Preamp has that feature.
What does polarity inversion do to the sound? I have a Chesky test CD that contains a phase inversion track. I cannot hear any differences?
What am I missing?
Vett93, your speakers are probably not polarity coherent (most aren't). I never heard polarity differences on that Chesky CD either, before I got my Gallo Reference 3 speakers.
I ended up with an Aesthetix Calypso linestage for this very reason (polarity switching via the remote). Plato, the Calypso offers both RCA and XLR inputs/outputs -- all of them -- another reason I like it. Dave
I really appreciate your help on this. Another fellow e-mailed me privately and suggested the Parasound Halo JC-2, which is also a very good candidate.
Regarding the audibility of absolute polarity, I have always had phase-coherent speakers and have always heard differences in my recordings when going from absolute polarity to inverted polarity. For whatever reason, I usually hear more of a difference if there is a tube component somewhere in the signal path.
The Modwright 36.5 has a phase inversion switch, and would be another fine candidate in your search. Not sure which of your amps you are looking to pair it off with so I cannot speak to synergy. There are a few reviews you could read online. The phase inversion is also on the remote for the 36.5.
My Audio Synthesis DAX decoder has switch.
Aesthetix Calypso. Adjustable via remote control or face panel.
The PS Audio GCP-200/GCPS is an outstanding value, discrete balanced pre, XLR/RCA- I/OS PLUS polarity control(though it is misnamed phase) on the remote!
IMHO, one needs polarity on the remote because many records/CDs are mixed up, and one needs to hear it from the listening position.
Another choice that's twice as much (MSRP) is the newish Parasound JC 2
My Bent Audio TVC has both a panel button and a remote button. I find the remote to be of particular value as some recordings have phase changes from track to track.
The focus seems to be on preamps, but I'll ofer that the Marantz SA11-S2 and SA7-S1 SACD/CD players have a polarity switch. They are excellent palyers for the money too.
Spectron Musician Signature III MK2 Amp
The Tube Audio Design TADAC has polarity switches for each channel. It helps that it's a wonderful tube output DAC with adjustable gain and "tubyness" control.
One of the first preamps to have the invert feature was the original Atma-Sphere MP-1 (1989). It is the one signal processing feature that we have on our preamps (easy enough to do since our preamps are internally fully balanced).
Spectron Audio power amplifiers and pre-amplifiers have this feature on EACH CHANNEL separately - extremely useful
Can someome explain why one would need phase inversion? I still don't understand....
I assume that it will invert both the L and R channels. So why is it useful?
If you have a recording that was done with 2 or 3 microphones, the effect can be heard. The effect has to do with the fact that audio waveforms are not always symmetrical. Take a look at an audio waveform on an oscilloscope and you will see what I mean. So the theory goes that if the waveform has some asymmetry, that there is only one way to reproduce it right.
The problem is that 50% of all CDs and LPs are 'out-of-phase', so its useful to have a switch. I knew an audiophile years ago that always reversed both speaker leads in order to determine which way was right, and then marked his recordings... a switch is a lot handier :)