Bottlehead Forum

General Category => General Discussion => Topic started by: aragorn723 on July 21, 2014, 05:08:22 PM

Title: checking system phase
Post by: aragorn723 on July 21, 2014, 05:08:22 PM
Hi,

Does anyone know of an easy way to check the phase of a stereo?  I have the following components:
1)  Rotel CD player
2)  Audioengine d1 dac
3)  Quickie preamp
4)  Inter-m R500 170X2 amp

None of them have a balance control, is there a way to check this without pulling the whole thing apart and re-checking every single wire and hookup?  I have noticed it makes a really big difference in how the stereo sounds.  Thanks!

Dave
Title: Re: checking system phase
Post by: galyons on July 21, 2014, 06:02:17 PM
Too hard to figure out the phase of all of the components in the chain.  I usually just listen to both phase orientations at the speakers and pick the one that sounds best, if there is an audible difference.

Cheers,
Geary
Title: Re: checking system phase
Post by: Doc B. on July 22, 2014, 08:23:52 AM
Do you guys mean polarity? Phase is pretty easy, if two channels are out of phase the music sounds "inside out". Polarity is about whether the speaker cones are moving forward or backward on a transient.
Title: Re: checking system phase
Post by: Grainger49 on July 22, 2014, 08:44:19 AM
I listen to the sound of a picked or plucked string on a guitar or mandolin.  When out of proper polarity the transient sounds blunt.
Title: Re: checking system phase
Post by: aragorn723 on July 23, 2014, 04:15:24 PM
yes, the question is about polarity.  There seems to be plenty of bass in some songs, though not as much with others.  I'm guessing there wouldn't be much bass in any song if the speaker polarity was reversed?  (Though maybe I reversed one and not the other!  ::)

Dave
Title: Re: checking system phase
Post by: Paul Joppa on July 23, 2014, 05:25:00 PM
It's an easy experiment to swap the polarity of one speaker.

If the speakers are close together you will usually hear a significant change in the bass level, but in ordinary listening locations it's mostly the weird sound rather than the level of bass that you hear. At least in my experience.
Title: Re: checking system phase
Post by: Grainger49 on July 24, 2014, 01:09:05 AM
This is the test used in the 60s and 70s to test if the speakers are moving together (in relative phase).  You face them to each other and play music with good bass content.  While the music is playing swap the + & - on one speaker.  If the bass increases they were out of phase.  If the bass decreases they were in phase.
Title: Re: checking system phase
Post by: Chris on July 30, 2014, 11:28:47 AM
I visited a guy who built a DIY set of Linkwitz Orions and I listened to a few tracks and the sound had some good audiophile qualities but the soundstage was strange in the imaging department and the bass was strange as well, like it was "sucking" when it should be "pushing" and vice versa.. I have never heard this out of polarity thing before, but I left his place thinking that maybe THAT was what I was hearing... Would I be correct??  Cause there was definitely something ODD about the sound he was getting.. And the strange thing, HE was quite pleased with the sound... maybe it was because he was the "Daddy" so to say... :)  Building them himself....
Title: Re: checking system phase
Post by: Chris on July 30, 2014, 12:05:38 PM
What I am asking is NOT about his build quality or the Orion speakers... I am just asking, IF the bass  or soundstage is "odd".. Could it be from placement being not optimum creating a bass "suck" and odd imaging? or can that be a polarity reversal?   This is all I am asking..
Title: Re: checking system phase
Post by: Doc B. on July 30, 2014, 12:37:58 PM
Open baffles can have cancellation effects by their very nature. It's a little hard to say what is going on without actually taking measurements in room.
Title: Re: checking system phase
Post by: Chris on July 30, 2014, 01:31:10 PM
Ok... a "cancellation effect"...hmmm yeah that makes some sense.. thank you... Could have been that.. Interesting...