Out of Phase Amplifiers

[jtsamarinda]

Could someone out there help me out on the following question.
I have a pair of JBL Hartsfield 1954 model.
The speaker at the terminal are in phase with a phase meter.

1. When I used my collection of Mcintosh tube amps: MC225,MC240,MC275.
And wire them up put a source input CD phase test cd, the output on the speakers
show out of phase.
So I have to reverse the wiring on the speaker side.

2. When I use the Marantz Model 8B or Model 9.
And do the same check with the phase meter it shows it is in phase.


Why is it so?
Thanks in advance.
Joseph Lazaroo
From Sunny Singapore.

[rusty jefferson]

Many manufacturers of audio gear invert phase as a way to simplify the circuitry and therefore improve overall sound. I've most often seen preamps invert phase, requiring the speaker connections to be reversed on the amp [unless the amp also inverts phase] to remain in absolute phase. I'm not familiar with the makers of your gear but perhaps one of your amps [and/or the preamp] is inverting phase. Check the owners manuals/websites to see. It's surprising how many people are listening to music out of phase because they bought a piece of equipment that inverts the phase and they don't realize it.

[jtsamarinda]

Many manufacturers of audio gear invert phase as a way to simplify the circuitry and therefore improve overall sound. I've most often seen preamps invert phase, requiring the speaker connections to be reversed on the amp [unless the amp also inverts phase] to remain in absolute phase. I'm not familiar with the makers of your gear but perhaps one of your amps [and/or the preamp] is inverting phase. Check the owners manuals/websites to see. It's surprising how many people are listening to music out of phase because they bought a piece of equipment that inverts the phase and they don't realize it.

Thanks Rusty,
It's interesting to know. I only found out these problem after purchasing the phase meter after I had problems with my other speaker (JBL Paragon).
After getting them fixed I started checking my other speakers and now amplifiers.

Thank You.