[ricmon]

Phase inversion has really transformed my system.  The effect is so draymadic that I'm wondering who else is using this technique.  Some of the effects are:

Alot more depth to the sound stage.
A dead quite background.
Resolution has seriously increased..............and the music is much easier to connect to.

As far as products on the market that offer phase inversion I have only found 3.

Audio Illusions, Audio by Van Alstine and Joule Electra.   So, has any one else using phase inversion?   Thoughts?

Ric

[Wayne1]

I'm not quite sure what you mean by phase inversion.

Are you referring to polarity reversal?

That is easy to do by switching speaker wires.

At the line level it is a bit harder. It would need a balanced circuit and a switch or a transformer and a switch.

Some tube preamps do invert polarity and you have to switch speaker wires to restore "absolute" phase.

There are some DACs that switch phase.

[ted_b]

What do you mean "it has transformed my system"?  What has?  The use of inverting absolute phase so recordings that are "accidentally" done in inverted phase can be tightened up?  You, of course, need to re-invert for those correct phase recordings (90%+)....and remember, any mutli-miked or multitracked recordings may have multiple layers that are either one phase state or the other.....

There are very many preamps and DACs that offer phase switches....Modwright, Bent Tap, Audio Research, Bryston, etc etc.   Squeeze Center has an absolute phase switch in its settings for the Transporter player.  I own three(Modwright pre and Transporter, and Bent pre) that do, and find the need to switch absolute phase on about 5% of my recordings, especially small single miked ones.  Somewhere on the web someone went through and denoted those minimally miked recordings where polarity was the inverted accidentally.

P.S.  I am not talking "out of phase" where one speaker is reversed from the other.  No switch will fix that, only fixing one of your red/black leads.

I would say that if leaving phase invert "on" has transformed your system then it was wired incorrectly to begin with, and you fixed it by inverting.

[Wayner]

I believe ricmon is actually referring to a Phase Inverter Bridge that is used to operate stereo amplifiers in "monaural mode, thus usually tripling the power output. To do this, you must have a phase inverter bridge that will put one of the signals of the preamplifier 180 degrees out of phase to run the other side of the amplifier times 2 for the other channel. In other words, the Phase Inverter Bridger has 4 outputs. This also requires 2 identical amplifiers.

Here is a link to the AVA Inverter Bridge: http://www.avahifi.com/root/equipment/bridge/insightbridge.htm

Here is a block wiring diagram:

http://www.avahifi.com/root/equipment/bridge/bridge_wiring_dual_mono.htm

Wayner 

[ricmon]

The system was not wired wrong and I have no idea how these amps are able to do this but I'll try to explain.  I'm using two stereo amps to power my system.  Orginaly I was using one channel per amp.  It is said that in this configuration the amps are able to some how draw power from both channels.  One day I decided to span the speaker connections across the positive post from both the left and right speaker post while suppliying input into only one channel per amp.  Yes at this point the speakers were out of phase.  I switched the positive/negative orintation and speaker phase restored with the aforementioned results.  Again I have no idea whats going on inside of these amps.

Ric

[Wayner]

Ricmon,

Perhaps I don't understand what you are doing, but what you described sounded scary. 

Wayner

[ricmon]

Ricmon,

Perhaps I don't understand what you are doing, but what you described sounded scary. 

Wayner

I thought so too......But all is well......the amps seem just fine but I am interested in other ways to achieve the same results.

[ted_b]

Sorry, Ricmon, you did not explain it was an amplifier bridging technique.  Most talk about inverting polarity via a preamp switch.

OK, so my Spectron monoblocks use phase inversion to double their power and triple their headroom.  They are both stereo amps, but then, in balanced mode, you invert the phase (switch on back of each amp, each channel) of one channel of each amp, and you y-adapter the balanced cables (or have it split internally)....directions explained on page link below.  The result has been an enormous increase in soundstage depth, blackness and overall dynamics over an already great stereo amp.

Here's an excerpt from the Spectron monoblock page link, possibly relevant for Ricmon's discovery:

Regardless of the efficiency of the speakers, balanced mode of operation doubles the slew rate and bandwidth by virtue of the out of phase transmission. This also suppresses the noise and buzz originated upstream from the amplifier. The other major advantage of mono balanced mode in Spectron amplifiers is that transmission of both positive and negative signals (in each amplifier) is maintained separately from the amplifier's input to the speakers binding posts. Assuming that the signal path electronics are matched, all of the intrinsic amplifier distortions arrive at the speakers with practically identical amplitude but with opposed polarity and essentially cancel each other. The result is a largely noise and distortion free sound transmission, leading to a spectacular improvement in three-dimensionality and resolution of detail in the music.

http://www.spectronav.com/monoblocks.htm

[Wayne1]

Ricmon,

Bridging amplifiers by that method has been around a LOOONG time. It is used in car audio, pro audio and home audio.

I am glad you are enjoying you amps.

[ricmon]

You guys have nailed it  The results are as exactly as describe by Spectron.

thanks  it's nice to know you hear what you hear.   Fantastic   

[JerryM]

I believe ricmon is actually referring to a Phase Inverter Bridge that is used to operate stereo amplifiers in "monaural mode, thus usually tripling the power output. To do this, you must have a phase inverter bridge that will put one of the signals of the preamplifier 180 degrees out of phase to run the other side of the amplifier times 2 for the other channel. In other words, the Phase Inverter Bridger has 4 outputs. This also requires 2 identical amplifiers.

Here is a link to the AVA Inverter Bridge: http://www.avahifi.com/root/equipment/bridge/insightbridge.htm

Here is a block wiring diagram:

http://www.avahifi.com/root/equipment/bridge/bridge_wiring_dual_mono.htm

Wayner 

Frank's Inverter Bridges can be used successfully with only one amplifier as well. 

Have fun,
Jerry

[ricmon]

For all that read this thread.........run don't walk over to AVA and pick up an inverter bridge.  This by far the most significat and profound change that I have ever made to my system.  BTW I not using an AVA inverter but the results should be the same.................  It's the only way to really HEAR the music.   

Enjoy