Out of phase breaking in, Anywone ever hear of it?

This is a technique I have used to break in speakers in the past.

Basically you place the speakers face to face with the drivers seperated by a small amount, maybe 2 inches or less between drivers. They you connect one speaker out of phase, negative wire to positive terminal. Finally you feed a mono signal, to the amplifier and play the sound at moderate levels.

The outcome of the process produces only a mild sound output since the out of phase signals largely cancel each other out. The cone range of motion is relatively large, and the speakers compliance is quickly opened up.

Care must be taken not to use this technique too long, you don't want to damage the speakers, just open the range up.

This has worked magic for me, shortening break in time dramatically.

Anyone else have any experience with this technique?
Thoughts would be appreciated.

Thank you,
Sure, I've used it many times. It really reduces the sound output sound and allows me to play my system 24X7 in order to decrease the break-in time required for my new speaker purchases. I sometime also cover the face to face speaker pair with blankets to further reduce the sound output.

I agree that caution is necessary because the sound is greatly reduced by cancellation and you could drive you amp into clipping or overdrive the speakers without knowing it. It's best to first play your system in a regular layout to determine what position on the volume control is moderately loud before doing the cancellation setup. Never exceed the volume control level that you previously determined was loud in a normal setup.

Thanks for the reply.

It doesn't look like many folks are familiar with this technique. You have made very good points about finding the appropriate volume level to do this with.

In my experience under normal conditions many speakers never break in properly. I have found many "used" speakers that I have purchased were not broken in at all.

As an example I once pruchased a pair of Klipsch Heresey's from a professional video recording studio. They carried them around for the audio portion of their demos. The seller said that they were "too much" for their application and were going for something smaller. After using this breaking in technique the bass really opened up. I would say the low end increased by a third in apparent volume and depth. I wonder what the seller would have thought hearing the vastly improved in performance the Heresys were really capable of.

Thank you,

I have also done this for the first couple of days to expedite the process. But typically after 3-4 days, I break down and just put the speakers in my system for the rest of the break-in period.
I use this technique regularly. Works great. It makes me wish for a preamp with an old fashioned Mono switch, though.
It's a standard method of break-in. Check the thread archives and you'll find it's used often.
"It doesn't look like many folks are familiar with this technique"
Hmmmmmm,I think most who have been here and did a search (BTW FAR TOO MANY IGNORE THIS FEATURE) atleast know of this and many have tried it....not sure what gave you that idea.
VS Audio regularly uses this technique to break-in their speakers and did this to mine for me.
Well this is a new method to me and thanks for posting,
anyone know the theory behind this method; it seems to me to possibly be working the excursion of the drivers the most; being that a positive signal the drivers would move forward and a negative signal the driver would move back toward rest; being reversed the opposite would happen.
Yep. Monitor Audio mention it and actually recommend this method on their UK website regarding their Gold Series speakers. They also mention throwing a Doona (Heavy blanket) over them! I don't if thats because it gets very cold in England or because their housing is very small and joined and its meant to keep sound to a minimum so you dont disturb your neighbours.
I don't think there's really any theory at all except to play your speakers hard. The out-of-phase thing is simply to minimize SPL during break-in, making the process more tolerable in normal living situations and, consequently, allowing you to play the speakers louder and longer than you would otherwise.
Either Stereophile or TAS recommended this procedure at least 20 years ago. As I recall, they also suggested covering everything with a couple of blankets to help reduce the level so as not to drive everyone in the house crazy!
Thanks for posting. I was not aware of the phase technique. Although many may be well aware, others have a lot to learn.