I have having major phase issues with my bass. I wired everything correctly. With my speakers and my old amp, bass sounded great with the speakers in phase with each other. Now I have it wired up in phase and the low bass is really bad. Then when I wire them out of phase with each other, the bass is better, but not what it should be. I have verified this by connecting just one speaker, and then seeing how much better the bass was after connecting the second. With the speakers wired in phase, the bass completely vanishes. With the speakers out of phase, the bass gets better but seems weird, and definitely not to the point that my previous am was. Up until now, I had only run single channel gainclones when I was expiramenting, and I was incredibly impressed with the bass.
To sum it up, and this has been verified time and time again, the bass is gone when the speakers are in phase, the soundstange is in front of me, but is not well defined.
When I wire one out of phase with the other, the bass is marginaly improved, but the soundstage is crazy like it is when you reverse polarity
I have checked and re-checked everything, please let me know if you have any ideas that could help me out.
Thanks,
Paul Hilgeman
To sum it up, and this has been verified time and time again, the bass is gone when the speakers are in phase, the soundstange is in front of me, but is not well defined.
When I wire one out of phase with the other, the bass is marginaly improved, but the soundstage is crazy like it is when you reverse polarity
I have checked and re-checked everything, please let me know if you have any ideas that could help me out.
Thanks,
Paul Hilgeman
Phase
Hi paul,
Check the phase of the bass speakers or that they are equally connected with a 1.5V battery. Convention is that the speakercone moves forwards when the "hot" or red terminal is connected to the plusside of the battery. Hope this helps.😉
Hi paul,
Check the phase of the bass speakers or that they are equally connected with a 1.5V battery. Convention is that the speakercone moves forwards when the "hot" or red terminal is connected to the plusside of the battery. Hope this helps.😉
Yes, they are correct, like I said, I have had these speakers for a while, and had them connected to another amp before, and they sounded great.
Thanks for the idea though,
Paul Hilgeman
Thanks for the idea though,
Paul Hilgeman
I got that from the ESP "Better Volume Control"
http://sound.westhost.com/project01.htm
I have used it both ways, I still have the phase issue with or without it.
-Paul
http://sound.westhost.com/project01.htm
I have used it both ways, I still have the phase issue with or without it.
-Paul
I only get .015 VDC across the output, and I can see no change on the woofer cones when I turn it on.
-Paul
-Paul
Ok. Scratch that anyway. I was thinking at the wrong end of the problem.
If you're truly getting significantly less bass with the speakers wired in opposite polarity, then I can't think of anything being the cause other than one of your amplifier channels being non-inverting, one of the channel outputs being wired opposite the other, or one of your speakers wired in opposite polarity either internally or externally.
se
If you're truly getting significantly less bass with the speakers wired in opposite polarity, then I can't think of anything being the cause other than one of your amplifier channels being non-inverting, one of the channel outputs being wired opposite the other, or one of your speakers wired in opposite polarity either internally or externally.
se
Steve Eddy said:
Hey, I think we might be a bit unclear on the problem here. I'll try again, forgive my poor descriptions.
In Phase with eachother:
-No bass, imaging is decent, not good, just barely decent. I can tell that somthing is wrong for sure though with the mid and trebble.
Out of phase with eachother:
-Bass has more presence, but still not where it is with other amps. Imaging is wacky, and spacy, there is that suckout feeling that you get when you wire them out of phase.
-Overall, bass is always better (deeper and louder) with one speaker hooked up.
It seems as though I am getting a phase shift in one channel, and I have no idea why.
I know that my wiring is correct, here is a pic. I have corrected the problem with the potentiometer (the middle pins sticking through) and the feedback resistor is on the rear side of the PCB. The twisted wires are the RCA inputs, and the straing ones go to the speakers. The caps are on the reverse side of the PCB as well.
-Paul
Attachments
Sorry, took a break to whip up some snackage.
I'm pretty clear on what the symptoms are.
Except that this is a classic symptom of one speaker being wired with the opposite polarity of the other.
This doesn't make much sense. Driving both speakers together could load down your power supply considerably more (seeing as you're just using 1,000uF reservoir caps) than driving one speaker, but that would tend to manifest itself by the amplifier's clipping sooner rather than playing louder or softer.
And I can't see any reason why such a drastic change in phase would take place in the chips themselves.
Color me stumped.
se
PaulHilgeman said:
I'm pretty clear on what the symptoms are.
Except that this is a classic symptom of one speaker being wired with the opposite polarity of the other.
This doesn't make much sense. Driving both speakers together could load down your power supply considerably more (seeing as you're just using 1,000uF reservoir caps) than driving one speaker, but that would tend to manifest itself by the amplifier's clipping sooner rather than playing louder or softer.
And I can't see any reason why such a drastic change in phase would take place in the chips themselves.
Color me stumped.
se
I am completely stumped as well. I am going to take it in to a lab to measure right now, i should have results by midnight or so CST. It seems as though the bass is partially out of phase, when the speakers are wired normaly. Then when I reverse the phase of one speaker, the phase alignment of the speakers is better, but not great, and the mid and treble is completely out of phase, creating the suck out effect.
-Paul
-Paul
Cap
Hi,
Why do you have no cap across the chip? Place 0.22-1uf across the + and - supply pins. It may not fix your problem but it will make the amp more stable.
Also be aware that the kind of cap you put there can change the character of the amp.
Cheers,
Anthony
Hi,
Why do you have no cap across the chip? Place 0.22-1uf across the + and - supply pins. It may not fix your problem but it will make the amp more stable.
Also be aware that the kind of cap you put there can change the character of the amp.
Cheers,
Anthony
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