Bridging a receiver? Bad idea?

Wolfmag
Wolfmag Posts: 23
edited October 2003 in Car Audio & Electronics
Ok as the subject says, has anyone tried or know what would happen if I tried to bridge my 4 channel receiver. So just recently, I pulled out my rear speakers in attempt to sell em and while driving to work today, I notice that it doesn't sound worse really with those speakers out, I hardly noticed them missing. It seems all I need are my two fronts! My car is quite small and my backseat is pretty useless anyways. No one but a child could comfortably sit there, lol.

Currently, my speakers are being powered my receiver. It's a Sony MP40 and according to its specs, it delivers 23 watts RMS to each channel. What if it were possible to bridge my four channel receiver to just 2 channels? That would effectively be 46 watts RMS to each channel right?

I was able to bridge my little 2 channel MTX amp (thunder 152) to power my sub by using just the positive of channel 1 and the negative of channel 2 (Thanks to you guys what I’ve learned here on this forum). So could I effectively do the same thing with my Sony Receiver? Use the Positive of my Front Left and the Negative of my Rear Left - and vice versa for the Right side?

Would my Receiver go up in smoke as soon as I turned the ignition or would it actually work?

If this question seems hilariously stupid, please forgive me, but please tell me anyways. ;)

-k
Post edited by Wolfmag on
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Comments

  • PoweredByDodge
    PoweredByDodge Posts: 4,185
    edited October 2003
    you'd probably fry it -- most receivers have "chips" instead of networks of transistors for output stages / amplification... as a result, you can't really beat on them at all...


    in short - dont bridge a receiver...
    The Artist formerly known as PoweredByDodge
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  • sntnsupermen131
    sntnsupermen131 Posts: 1,831
    edited October 2003
    agreed...plus...your front speakers probably wont take a 2 ohm load anyway
    -Cody
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  • C-Man
    C-Man Posts: 307
    edited October 2003
    I agree with Cody and Dodge, most HU's will list a minimum impedance of 4 ohms stereo power. You throw a 2 ohm mono load on there you're gonna fry that beast.
    If you're gonna try to throw together the front and rear channels to bridge to each speaker... I believe what you'll get is speakers that sound hollow and crackly and poppy and a fried HU. If I remember correctly from my past experiences.
    "The Big C"
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  • Jstas
    Jstas Posts: 14,804
    edited October 2003
    Well, it has been a very long time since I last saw a head unit that could be bridged. The last time I saw it was like 1993-94 when Alpine had a head unit with seperate MOSFET power supplies. At least I think it was Alpine. Might have been Eclipse or (GAH! The horror!) Sherwood! I can't remember though. Anyway, most stuff now has plenty of power per channel that bridging isn't really needed. If you need that kind of power, you can pick upa cheap stereo amp that is bridgable for like 50-100 bucks. I have a Kenwood 35Wx2 RMS 70Wx2 Peak stereo amp that when bridged put out like 70-100W x 1 RMS and 200W x 1 peak. Also, an aftermarket amp is more likely to handle a 2 ohm load without a problem.

    It's not worth the wiring headache that it could be to try and bridge a reciever or head unit. You'd really need an external secondary output stage with its own power supply. At that point though, just buy an external amp.
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
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