SH Spotlight SH Forum members: Are your speakers in correct phase?

The 1st Stereophile test CD has a pink noise track recorded both in stereo and mono that I find useful to check phasing.

 

I learned many years ago that an amplifier must never be powered on "open circuit", i.e. without a load. Whenever I have to disconnect speakers, I always make sure that the amplifier is powered down. Does anyone know if this is still necessary with solid-state amps or is it just a habit carried over from using valve amps?

 

My amp is powered up 24/7 so I'm grateful it has a mute switch as it allows me to plug/unplug cables without turning the amp off.

 

Very necessary. Trust me.

 

That is true but I always check connections carefully before I turn off the mute switch.

 

• Was going nuts chasing wires a few weeks ago until I realized that one of my speakers was accidentally cross-wired internally, i.e., the connections on the inside of the speaker going to the clips on the back were flipped. As soon as I reversed the wires to 'un-cross' the connection from the clips to the amp everything fell into place.
• I also found some phase test audio clips on YouTube to be extremely helpful, and frankly a little more obvious than playing a mono recording.

 

Which, when you think about it is a safe practice with anything electrical.

 

Some speaker designers do wire the tweeter out of phase.

 

No, this was the main driver. I realized it sounded 'off' but was confused because the wiring looked fine. As soon as I flipped the one set of wires though, the sound came into phase.

 

I thought directionality on cables was "snake oil"?

 

The alternating current travels from your amplifier to the speakers and provides the power to move the speaker cone in one direction, a fraction of a second later the current reverses direction and travels back from the speaker to the amplifier, moving the speaker cone in the opposite direction. This happens thousands of times per second.
However when the electrons travel towards the speaker it is important they can read the brand name along the side of the cable, having been suitably impressed by the expense of your SuperMagicCable9000 they will obviously make an effort to perform better when reaching the speaker cone.
(When returning back in the other direction, this doesn't matter because they will already have read it by then.)

 

Sometimes listening to The Beatles SirusXM channel on my car radio [whole car bought on the cheap with as little money put into it as possible], I find myself wondering.... "Is that a different mix...? or are my speakers just wired out of phase..?"

 

Internally as a crossover design choice, sure-but I assumed

meant that one speaker was out of phase compared to the other speaker, which should not be the case.
- I'll also note Audyssey would say we had a speaker out-of-phase though we re-checked the connection. I'd hope Focal wouldn't screw up like that.
- Come to think of it I have not done a basic low frequency tone phase flip test, d'oh!

 

That is funny!

But actually, it is a good tool to test...I could have disconnected the mid/tweet of the Focal 936 and rerun the Audyssey to see if it still reported "out of phase" (which can be from reflections it seems or something, I forget exactly). However now we have moved on to an Anthem AVM70 with ARC, no phase issue reported.

 

Interesting you bring this up. I wired a new pre/pro that had an Audessey set up for speaker calibration. I'm pretty careful about wiring but when I ran the program the first thing it told me was my right front was out of phase, and darned if it wasn't right.

 

Stereophile used to sell a nice test CD where they had recorded a bass guitar in phase on one track and then recorded out of phase. The in-phase track was dead centre between the speakers (if the wiring polarity was correct) and the out of phase track had no central image and sounded kind of spacey. Of course if your speakers were out of phase you got a central image with the "out of phase" track.

 

Before he became an aeronautical engineer, my pop worked for Ampex. He showed me how to set up stereo equipment properly from the get-go. I kind of grew up with this notion that if I did it wrong, my stereo would blow up, or worse, I might have to do time in hell.
It's all good here!