Axiom Home Page Forums General Discussion Home Theater THX Monoblocks with M80's

Sorry I haven't been responding to other posts, have been extremely busy. Apparently my hunger for power does not end. I recently added a Marantz THX Ultra MM9000 Amp to my set-up originally designated to drive the main 5 channels. However, I have just purchased (could not pass up the opportunity) 4 Marantz MA-700 THX Ultra Monoblock Amplifiers. They put out 200W @ 8 ohms, and 300W @ 4 ohms, 600W with two bridged at 8 ohms. I plan on bridging them for driving the 4-ohm M80's. Does anyone know the actual output with 4 ohm bridged? Any opinions?

Massive.

Massively overkill, way more than you'd ever need. That's how much.

How much did you pay for those baddies?

a good guestimate would be around 700watts - enough to split your head open, blow the speakers apart and really impress your friends.

REMEBER, wear safety goggles.

^billy

I'm reminded of scenes from Back to the Future (guitar amp scene) and Spinal Tap ("These go to 11").

Technically of course, in the Back to the Future scene, the amp should have blown up (or been way, way louder) before it did. You can hear the strings moving slightly before he strikes the chord.

Yes, I just got the DVDs!

Yes, I am a nerd!

Paid 1100 inclusive of shipping. So now I have the two monoblocks driving one speaker, the other two the other speaker...

The center, left surround, right surround, left back surround and left right surround will go to the MM9000 THX Ultra Amp -- I don't know the 6 ohm wattage but probably around 200 or so. Oh, and I still haven't ordered the 20-39 PC+ sub from SVS. Still torn between the cylinders or the boxes.....I'm gonna debut this bad boy with the Last Samurai

I would bi-amp each M80 instead of bridging the amps. Better to have better sound than more power, I think.

Sorry to say but I do'nt believe you can bridge those amps and still drive a 4 ohm load.Doing so the amps would see the load as a 2 ohm load not 4.If it were M60's it would work seeing they are 8ohm and then bridged the amps would be seeing them as a 4 ohm load.I too would bi amp not bridge.

AJ, be a bit careful, as wid said if you bridge the 700s to drive 4 Ohm speakers, the effective impedance is actually 2 Ohms. The power output would be approximately twice the output of the 700 at 2 Ohms, which I estimate would total about 800 watts(if the 700s can handle 2 Ohms). Remember what they say about power tending to corrupt. Control your lust.

I have to find out if they can handle 2 ohm -- how do I go about bi-amping, and what would the effective wattage be for each speaker seeing as they'd have two amps each? It's hard to control my lust....

Here is a link about bi-amping:

ok, the url code isn't working properly, here is the address:

http://sound.westhost.com/bi-amp.htm#basics

In general terms, bi-amping uses two amps per speaker cabinet: one to power the mids and tweeters, the other to power the woofers. Because bass requires a lot more power than mids and highs, separating the two ranges can be very beneficial, especially if you like to listen to loud or dynamic music.

To bi-amp, you first need to remove the metal strap that connects both pairs of terminals on the back of the speaker. This will electrially separate the mids/tweeters from the woofers. Then you run one pair of cables from one amp to the upper pair of terminals, and a second cable from the second amp to the lower pair of terminals.

If you want to take it a step further (as mentioned in the link Riffman posted), you can install high pass and low pass filters in front of each amp so that only the mids and highs are being passed to the upper terminals and only the bass is being passed to the lower terminals.