4 channel, 1 sub
06-13-2005, 07:12 PM
#1
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Ok, I just want to see if anyone knows if this won't work. I have a 4 channel amp, 1 sub with dual 4 ohm voice coils. I can bridge both front and rear channels on the amp, and also run them both on the front input only. Now this means, to me, that I'd be able to hook up one coil to each bridge Therefore using the amp to it's full potential on one sub...someone stop me if I'm wrong...
P.S. The sub is 300rms and the amp is 150X2rms
[ June 13, 2005, 08:13 PM: Message edited by: J.R. ]
P.S. The sub is 300rms and the amp is 150X2rms
[ June 13, 2005, 08:13 PM: Message edited by: J.R. ]
06-13-2005, 07:59 PM
#2
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Yes, this can definitely work but there might be a problem if you can't match the levels between the front & rear output channels. If you can't, then one coil would be getting more power than the other & problems may arise.
06-15-2005, 06:08 PM
#4
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Well thanks for the advice. Of course what you didn't understand from my first msg, is that there is a front only switch on the amp. Sorry I should have been more clear. this switch enables me to run both front and rear channels off the front input only, therefore not having to match up anything. I have successfully hooked it up...it runs awesome! I also hooked up my phoenix gold line driver, which has a handy little light the turns on when I'm at risk of damaging the speakers (or sub in this case).
Of course I agree with you both when you say there are major risks when you have to try to match up gains and crossover's and such. I would also advise people not to even attempt it...unless you have a switch which will enable you to do so safely, do your reading and understanding before you test...and asking never hurts!
thanx again
[ June 15, 2005, 07:19 PM: Message edited by: J.R. ]
Of course I agree with you both when you say there are major risks when you have to try to match up gains and crossover's and such. I would also advise people not to even attempt it...unless you have a switch which will enable you to do so safely, do your reading and understanding before you test...and asking never hurts!
thanx again
[ June 15, 2005, 07:19 PM: Message edited by: J.R. ]
06-27-2005, 08:00 PM
#6
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UPDATE!!
Well, altho everyone is worried about front and rear gains, as I tried to say before, when it is in "Front only" mode, only the front gain does anything. I was getting curious about this, so I tried it. I tried cranking the rear gain while playing it quietly (so I wouldn't blow anything, just in case) and it did nothing, as I expected. Thanx for the worries tho!
Be loud!!! For those who can't be!!! (like me)
Well, altho everyone is worried about front and rear gains, as I tried to say before, when it is in "Front only" mode, only the front gain does anything. I was getting curious about this, so I tried it. I tried cranking the rear gain while playing it quietly (so I wouldn't blow anything, just in case) and it did nothing, as I expected. Thanx for the worries tho!
Be loud!!! For those who can't be!!! (like me)
06-27-2005, 08:59 PM
#7
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wrong, soo wrong. wrong. the front switch enables you to run BOTH front and rear off the front channel input but you still have independant gains between the two. i would just run the rear to the sub and the front to your speakers. its an ok setup thats what i am running now its works pretty ok.
06-28-2005, 08:05 AM
#8
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Run them both. Here is how you set the gain. PLay a tst tone below the crossover point, say 60 Hz. Now measure the output of the first bridged channel with a DMM set to measure AC voltage. Now put the DMM on the second bridged output and turn the gain until the number matches. You may have to repeat the process a few times to get the sub to the level you want to integrate with rest of the system (unless you have a sub level control, then it is much easier).
06-29-2005, 05:52 PM
#9
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ok, if I'm sooooo very wrong on this, then why does the output level only change when I turn up the front gain, and not when I turn up the rear gain???? by what you all are saying, Technically, if I turned up the front gain only, output level would go up (making it louder), but would also be unbalanced...now then if I only turned the rear gain up, it should also increase output level (making it louder), by also be unbalanced...however this is not the case...If I only turn up the rear gain, nothing changes, therefore doing nothing, therefore not making it any louder...now why would this happen if the rear gain actually did anything...not too mention, if I've been running it like this for over 2 weeks now, would that not screw up the sub?? Sure what you are all saying makes sense, therodically, but I'd think something would screw up if I was doing something wrong?? I dunno, I've never had to screw around with this stuff before, I'm new to the cheap setup scene. I've done pricey, and cheaper, but never cheap, so I dunno. Ah well if it screws up, it's only a $150 sub. thanx again for all your inputs
06-29-2005, 11:09 PM
#10
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There is no problem running two voice coils on separate channels, even if they are at slightly different gains. I could get into a description why, but it would just be easier if you read this PDF:
http://www.adireaudio.com/Files/Tech...oilDrivers.pdf
page 2, 5th paragraph down, "There's one thing that often comes up about wiring DVC subs"
for those of you not willing to read it all, the bottom line is that if you examine the extreme cases of when you have different signals on the voice coils you will find only two situations. situation one: the fields assist each other, thats what you want, double the output. Situation two: they counteract each other, but this isn't bad. The two signals counteracting will not rip the voice coil apart they will simply apply no net force to the coil and it will return to rest.
[ June 30, 2005, 12:09 AM: Message edited by: zarx ]
http://www.adireaudio.com/Files/Tech...oilDrivers.pdf
page 2, 5th paragraph down, "There's one thing that often comes up about wiring DVC subs"
for those of you not willing to read it all, the bottom line is that if you examine the extreme cases of when you have different signals on the voice coils you will find only two situations. situation one: the fields assist each other, thats what you want, double the output. Situation two: they counteract each other, but this isn't bad. The two signals counteracting will not rip the voice coil apart they will simply apply no net force to the coil and it will return to rest.
[ June 30, 2005, 12:09 AM: Message edited by: zarx ]
