Thread: 6-channel amp for 7.1?

First of all I would addrsss the issue of why you want 7.1?

99.5% of movies are still mixed in 5.1 or lower. Most 7.1 mixes you see on DVDs are matrixed mixes , i.e. the addition 2 channels are mathmatically created and do not reflect thr original source. So sticking with a 5.1 setup makes a lot of sense.

Or if it's to simply fill the car with sound then i'd recomend better quality over greater quantity.

The center channel will be powered straight off the soundcard

This seems very odd to me.

and the amp will drive the front, side and rear channels

Sounds fine to me.

Can I then bridge a single 10" sub on, say, the front channel (so I can still have subs while in 4 channel mode)?

Yes, most amps allow for tri-mode operation, you will however have to add suitable caps to your front speakers to act as a high pass filter, and a suiltable inductor on your sub to act as a low pass filter. Alternatively hunt down a phoenix gold xvr crossover which will do all this for you.

Or will this give me too much power to the front (reducing the Ohms)?

If your amp is tri-mode capable and designed to run down to at least 2ohm stero you should be fine as long as you stick with 4ohm speakers and sub.

PS you will loose discrete sub signal/control buy not running it of it's own channel.

If you really want 7.1 - and I really don't think you want 7.1. I think you want 5.1.

Lots of audiophiles actually just have regular stereo (2.1 - TWO CHANNELS), because the extra speakers just add sound interference and reduce the quality of the sound.

So given that very little content is 7.1 surround, I think you really want 5.1.

So given that, I think the a more reasonable way to do 7.1 would be:
1) get a 5 channel amp for your 4 corners + center
2) get a 2 channel amp for your 2 side speakers
3) get a 1 channel amp for your subwoofer.

Then again, I think most 5 channel amps are for 4 channel + sub, in which case you would just get a cheap mono amp for your center channel.

And then again, not to shoot your idea down, but I think 5.1 is a much better goal sound quality wise and.. just.. practicality wise. Sort of like why Gillette has a 5 blade razor, but they don't make a 10 blade razor. More is not always better..

7.1 because the rear channel is going to be set up also for viewing the drop-down 22" widescreen from the hatch for tailgating
And for actual 7.1 surround content, well, why not? Sure it won't be used 99.5% of the time, but it's the .5% that matters.

I'm going with Boston Accoustic Pro60's front and side, and 5 1/4" MBQuart seperates(with passive crossovers) for the rear, so actual 'mode' of the amp is moot I think...
The Pro60's will be bi-wired thru their crossovers, so everything is covered except the sub...but I don't think it matters if full range goes to the sub. It won't hurt anything, right?
Amps will be 2 Ohm stables, yes...

Or I might go with a 2 channel amp for the rear, and a 5 channel for everything else...

My center channel is a powered Logitech mm28 flat NXT panel speaker...driven out of the Auzen Xplode, there is PLENTY of power for center channel use...why is that strange? What powers your desktop speakers?

Also, the sub runs from the center channel output from the soundcard, which is typical...
So maybe a two amp (2 channel/5 channel) would be better suited for my application...

[QUOTE=krnpimpsta;1167989].

Then again, I think most 5 channel amps are for 4 channel + sub, in which case you would just get a cheap mono amp for your center channel.

QUOTE]

Center channel and sub channel are not discreet...they run off the same channel, unless, perhaps it's 5.1 DTS...

Originally Posted by WuNgUn

My center channel is a powered Logitech mm28 flat NXT panel speaker...driven out of the Auzen Xplode, there is PLENTY of power for center channel use...why is that strange? What powers your desktop speakers?

I found that strange because the only time I ever experienced passive speakers (powered by sound card) was when I got a pair for free with my first ISA sound card on my 386 (before PCI cards existed).

My current speakers? They're logitech branded and powered by a big amplifier in the subwoofer. Even at work, the cheapy freebie speakers are powered by external power.

The sound card outputs a "line level signal," as in this is basically just the signal - the data. Not enough power to actually create alot of sound, unless you are powering very small speakers or a pair of headphones.

I don't know what kind of flat panel speaker you have, but I don't know of any audio technology that is capable of creating sound volume that can rival even a crappy stock car audio setup with just a line level signal.

Originally Posted by krnpimpsta

I found that strange because the only time I ever experienced passive speakers (powered by sound card) was when I got a pair for free with my first ISA sound card on my 386 (before PCI cards existed).

My current speakers? They're logitech branded and powered by a big amplifier in the subwoofer. Even at work, the cheapy freebie speakers are powered by external power.

The sound card outputs a "line level signal," as in this is basically just the signal - the data. Not enough power to actually create alot of sound, unless you are powering very small speakers or a pair of headphones.

I don't know what kind of flat panel speaker you have, but I don't know of any audio technology that is capable of creating sound volume that can rival even a crappy stock car audio setup with just a line level signal.

Read a little closer...I said it's a Logitech mm28, and it's powered...
And it's capable of holding it's own in the car!