How do I Bi-Amp

[boettinger]

Im thinking of b-amping 2 - a52's on the front and center channels and using the remaining 4 channels for the rear and back channels. How do I do this? Do I split the unbalanced outputs from the C2 using some type of splitter?

Is this a good idea? Will I gain anything or do you think it's a waste? reason I ask is I have an opportunity to pick up an A52 for a good price and use the two channel amp for a second zone.

Sorry if this is an elementary question.

[Peter Nielsen]

It depends on whether you want to do Active or Passive biamping. With passive biamping all you need is a simple signal splitter.

For the best result (and a noticable difference in sound quality) you need to do true active bi-amping. However, note that this requires speakers that let you remove or defeat the internal passive speaker crossovers. This is by far the best solution, since you eliminate a few components in the signal path that inherently degrade sound quality (no matter how good they are).

Here's a good summary: http://www.hometheaterforum.com/htfo...?postid=547067

You run the C2 outputs into an active crossover that splits the signal into a high pass and a low pass output that you feed to your amps. The amps are then connected to the speaker (with the internal crossover removed).

Here are a few crossovers that are generally recommended for Audiophile use:

Marchand ($500+) http://www.marchandelec.com/
Bryston ($1800+) http://www.bryston.ca/crossel.html
DEQX ($3000+) http://www.deqx.com
Pass Labs ($6000+) http://www.passlabs.com/preamps/xvr1.htm

If you're on a budget, there are cheaper crossovers available (starting below $100) :

Behringer http://www.behringer.com/
Rane http://www.rane.com

Peter

[nicholtl]

So Peter, the question is, when will you bi-amp ALL of your speakers??

[Peter Nielsen]

So Peter, the question is, when will you bi-amp ALL of your speakers??

My surrounds (MG 3.6s) can easily be bi-amped since they have an external removable passive crossover. Before getting the last two JC1s, I was seriously considering going with a pair of A21s for biamping the surrounds. However, my feelings about the A21 are mixed, so I finally decided to do 2 JC1s instead. With future service in mind, I think that using all JC1s is a wise choice. Using 4 JC1s for the MG 3.6s would be totally overkill - it's already on the verge of overkill for the 20.1s which are rated @ 500W. (The JC1 delivers 800W since Maggies are 4 ohms).
My center (CC3) and rears (MGMC1) cannot be biamped without serious surgery

FWIW, I'm not done with the fronts yet. I still need to purchase a DEQX and a second Martin Logan Descent sub so that I can tri-amp the fronts (biamping the MG 20.1s and using stereo subs for the low outputs of the DEQX) :B

Peter

[boettinger]

Thanks Peter, So if I understand you correctly, It sounds like I would be better off with a larger Amp Like the 21 wired normally than passive Bi-Amping a smaller one like the 52?

[Peter Nielsen]

Thanks Peter, So if I understand you correctly, It sounds like I would be better off with a larger Amp Like the 21 wired normally than passive Bi-Amping a smaller one like the 52?

Well, first, do you need a larger amp? If so, then the A21 might work out ok without biamping. However, biamping with the A52 will still have the advantage that the strain on the low pass (bass) is separated from the high pass (mid/treble), which may improve the sound. For instance at high bass loads, the mid/treble amp is not suffering from the high load at all and sounds completely clean. If a single amp is used, the high bass load might affect the sound of the mid/treble too, and the sound distortion will be more audibly noticable.

Note, however, that if you really need a bigger amp, then biamping will not necessarily solve the problem completely. Usually the low pass will require (much) more power than the high pass, so biamping with the A52 will really not solve the problem since it does not provide additional power to the bass that needs it. The best solution in this case would be to power the low pass with an A21 and use two channels of the A52 for the high pass...

Peter

[boettinger]

Thanks again Peter, No I don't need more power, actually I was initially just looking to power a second zone and came across a nice 5 channel Amp, then my head started spinning with upgradeitis...hence the questions. Now I think I have a grip on my options. My set up is actually fine for my room etc, but you know, can never have enough power or too complicated a set-up...

This whole hobby is so much fun, If only money grew on trees.

Thanks again.

Bob