Hi
does any one have an idea where to find some kit for subwoofer which have controls for phase (beside frequency and volume) ?
I have search ebay but could not find any...
there are number of chines kit's with frequency cut of, and volume but non of them have phase controls.
The thing is that I have a sub inside coffe table and it's like 50cm from my siting place and the main speakers are like 200cm...
(have XXLS12 sub, 300W amp...but need some controls for subwoofer )
thanks
does any one have an idea where to find some kit for subwoofer which have controls for phase (beside frequency and volume) ?
I have search ebay but could not find any...
there are number of chines kit's with frequency cut of, and volume but non of them have phase controls.
The thing is that I have a sub inside coffe table and it's like 50cm from my siting place and the main speakers are like 200cm...
(have XXLS12 sub, 300W amp...but need some controls for subwoofer )
thanks
tnx
but could you please posta a link
as I don't get any results browsing thair page
I don't need plate amp
just electronic which can control ''phase''
and I don't minde if it's in kit form (pcb, resistors, capacitorst that I have to solder...)
Attachments
Hi,
Here is another implementation of a phase control circuit, with some additional references/links:
Project 103 - Subwoofer Phase Controller
Just one more:
http://www.diyaudio.com/forums/solid-state/1700-subwoofer-variable-phase-control.html
Regards,
Here is another implementation of a phase control circuit, with some additional references/links:
Project 103 - Subwoofer Phase Controller
Just one more:
http://www.diyaudio.com/forums/solid-state/1700-subwoofer-variable-phase-control.html
Regards,
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Sorry Yoke, I misunderstood what you wanted. This is supposed to work - https://www.minidsp.com/products/minidspkits/2-x-in-4-x-out. Look at the application notes.
Thanks bjorno
this looks easy to build even via point to point 😀
Thanks tb46
the project106 was the first thing that I found and was hopeing to find some pcb or kit based on it...but no luck...
the one that bjorno post is easyer to build than eliots...i hope 😀
the link that you post, to another theme on diyaudio is interesting but I can't see the final version of circuit...don't se last picture that Danne post...maybe it's an old tread and the link to picture doesn't work any more...
and I'm not EE so I can't figure values on my own 😀
I need something which is a final project 😀
no probem
the mini DSP is always an option, but, will have to see/figure out, what to chose..
i wos hopeing that there are some kits that are less expensive from miniDSP and doing the sime thing...
Thank you all once again for advices
Josip
Rythmic Audio
These are servo controlled subs that incorporate phase adjustment in the power amplifier.
For Products See: Rythmik Audio • Servo subwoofer products
For Technical See: http://www.rythmikaudio.com/download/A350_SE.pdf
For Phase Adjust See: Rythmik Audio • Advice - phase alignment page 1
WHG
These are servo controlled subs that incorporate phase adjustment in the power amplifier.
For Products See: Rythmik Audio • Servo subwoofer products
For Technical See: http://www.rythmikaudio.com/download/A350_SE.pdf
For Phase Adjust See: Rythmik Audio • Advice - phase alignment page 1
WHG
You made the same mistake I did, whgeiger. Yoke is looking for a circuit or kit to just add phase control to his existing sub.
Jea, sorry...it's my mistake, I wasn't clear enough what I nead...
I have it in my mind, but somehow messed up a question while posting...
Thanks
What he probably wants (or should want) is a polarity switcher. What good would phase adjustment bring?
My experience - in real rooms - is that you need to try* both polarities and pick the pattern of peaks and dips you like the best with most of your sources. While this may horrify the sim-compulsive here, it certainly will be the case with OP's set-up.
Easiest way is to get a low resistance DPDT switch inserted into the driver leads.
Ben
*you can waste endless hours trying to figure which way sounds best by ear or you could do measurements at your chair in a few minutes and see how the two polarities produce different peaks and dips... and then confirm by ear.
My experience - in real rooms - is that you need to try* both polarities and pick the pattern of peaks and dips you like the best with most of your sources. While this may horrify the sim-compulsive here, it certainly will be the case with OP's set-up.
Easiest way is to get a low resistance DPDT switch inserted into the driver leads.
Ben
*you can waste endless hours trying to figure which way sounds best by ear or you could do measurements at your chair in a few minutes and see how the two polarities produce different peaks and dips... and then confirm by ear.
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As I understand
I should have the phase control to even time/distance be twin main speakers and subwoofer.
So I don't know how simple switch of polarity can help ? it have only two position, in phase and reverse phase ?
and maybe non of them (those two) would work at my seating position.
and, as my subwoofer (down firing ) is basically a coffee table, it's placed in the midle of the room without the option to move it around and trying to find best position for optimal performance...I was hopeing that phase control would do the trick 😉
here is one picture
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What I was saying was that EVEN a polarity switch is no a guarantee of having accurate time-alignment. So just fudging timing by phase adjustments (and all we are talking about is the crossover overlap with 3 meter wavelengths and where many factors of crossover, drivers, and room screw up phase) is hardly worth fussing about.
Ben
@ yoke
bjorno Post # 4 or tb46 Post # 5 will give you what you're asking for 🙂
A polarity switcher will Not ! It will only give you a fixed 180 degree flip option. Variable phase controls are made for a good reason 😉
bjorno Post # 4 or tb46 Post # 5 will give you what you're asking for 🙂
A polarity switcher will Not ! It will only give you a fixed 180 degree flip option. Variable phase controls are made for a good reason 😉
Perhaps you could explain those reasons as applied to the OP's situation.
I have a sense that you don't really understand polarity, phase, wave length, and time-alignment in relation to speakers situated in odd locations and crossovers. Too many posters are misled by textbook illustrations that show phase and anti-phase annihilating one another. The phases are all over the place: timing is the correct terminology. You can't just dial in some phase and have every note click into place - except for some micro-tone spot. That's Audio 101l
You can adjust time-alignment and that will help percussion music a bit.
B.
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Hi Y'all,
Interesting subject, here is another article from Elliott Sound "Phase, Time and Distortion in Loudspeakers":
Phase, Time and Distortion in Loudspeakers
The main thing you can do is adjust level and phase within the frequency range where subwoofer and L/R main speakers overlap. For this you could use 1/3 octave warble tones and a cheap SPL meter. Once you achieve a balance you can still fiddle w/ the controls, just don't deviate too far.
I'm still looking for a cheap and easy solution to the OP's original question, there should be something out there?
Regards,
Interesting subject, here is another article from Elliott Sound "Phase, Time and Distortion in Loudspeakers":
Phase, Time and Distortion in Loudspeakers
The main thing you can do is adjust level and phase within the frequency range where subwoofer and L/R main speakers overlap. For this you could use 1/3 octave warble tones and a cheap SPL meter. Once you achieve a balance you can still fiddle w/ the controls, just don't deviate too far.
I'm still looking for a cheap and easy solution to the OP's original question, there should be something out there?
Regards,
Timing not phase.
There's no generally good solution. A DPDT switch to change polarity might be helpful in the event that one polarity sounds any better than the opposite (don't count on that, whatever your sim says).
Think of it this way: you need to delay the sub a fixed amount (say, 5 milliseconds (about 5 feet)) so that it no longer arrives before the main speakers which are 5 feet behind. BTW, that will define a single spot for time-alignment for all frequencies from all speakers*, say your left ear. All other spots will have totally screwy and unpredictable and uncorrectable phase varying very loosely according to pitch.
As I posted earlier, doing time-alignment (which requires a DSP or some gizmo with a spring in it) is audibly beneficial. Depends on your room and system. With OP's echo chamber shown in the photo, I doubt it would be much help.
Ben
* the truth is that a lot more factors screw around with the phase of a note that flows out of a speaker, but as a generalization, "all" isn't bad.
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@ bent oronto
Speaking of 101 😀
Subwoofer setup and integration 101: sub crossover frequency, slope and phase for two channel systems Subwoofer setup and integration 101: sub crossover frequency, slope and phase for two channel systems - Acoustic Frontiers
Next we set the phase ! Soundoctor - Test CD V 2.7.2
Loudspeaker time alignment https://en.wikipedia.org/wiki/Loudspeaker_time_alignment
What does your "sense" say about the people posting the Variable Phase info in the above links ? You saying they don't really understand polarity, phase, wave length, and time-alignment too ?
Speaking of 101 😀
Subwoofer setup and integration 101: sub crossover frequency, slope and phase for two channel systems Subwoofer setup and integration 101: sub crossover frequency, slope and phase for two channel systems - Acoustic Frontiers
Next we set the phase ! Soundoctor - Test CD V 2.7.2
Loudspeaker time alignment https://en.wikipedia.org/wiki/Loudspeaker_time_alignment
What does your "sense" say about the people posting the Variable Phase info in the above links ? You saying they don't really understand polarity, phase, wave length, and time-alignment too ?
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