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lumiere
03-30-2004, 06:19 PM
HI, I'm new to this, so bear with me. I was wondering if it is possible to bi-amp using the preamp outputs in my integrated Musical Fidelity A3.2, using a matching power amp to drive the woofers of my speakers. Any thoughts?
Thanks in advance.

Studio B
03-30-2004, 09:04 PM
If I'm reading you right you want to use your pre-amp to power the high frequencies? In that case no can do. What you need to do is purchase an electronic crossover, or use the built in crossovers and a second amp. That is true bi-amping. Hope this helps.

Studio B
03-30-2004, 09:08 PM
If I'm reading you right you want to use your pre-amp to power the high frequencies? In that case no can do. What you need to do is purchase an electronic crossover, or use the built in crossovers and a second amp. That is true bi-amping. Hope this helps.

Scratch that. Getting late. I think it would be a perfect match as long as the power ratings match.

topspeed
03-30-2004, 10:28 PM
HI, I'm new to this, so bear with me. I was wondering if it is possible to bi-amp using the preamp outputs in my integrated Musical Fidelity A3.2, using a matching power amp to drive the woofers of my speakers. Any thoughts?
Thanks in advance.

I would think this would work only if the onboard amps aren't bypassed when using the pre-outs as in a receiver. It's an interesting question tho because I'd never considered it, but then again I've never found bi-amping to be good idea unless you're using completely different amps for the highs and lows, such as a tube for the highs and a ss for the lows.

92135011
03-30-2004, 11:20 PM
I think its the gain that has to match rather than the power rating.

or...maybe I'm on crack

gonefishin
03-31-2004, 05:19 PM
yeah, you need to match the gain for each amp or attenuate the signal "down" in front of one of the amps to level match.


Unless the passive crossovers in your speakers were made to operate independently from each other, I wouldn't bother.



take care>>>>>>>>>>>>>

Studio B
03-31-2004, 06:27 PM
I have yet to see gain controls on home audio equipment. Are you refering to the On Screen level controls available in the receiver?

bturk667
03-31-2004, 07:19 PM
Matching the gain is more important. Power matching is not necessary. A woofer requires more power than either a mid-range or tweeter. Therefore, one can use a smaller amp to power those drives, while using a larger amp to power the woofers. This of course only holds true if you are horizontally bi-amping, not vertically.

Vertically bi-amping would require using the same amps.

bturk667
03-31-2004, 07:24 PM
No, each amplifier produces a certain amount of voltage gain; as do active pre-amps. My amplifier has a voltage gain of 29 db. This is the number you have to match when bi-amping!

markw
03-31-2004, 07:45 PM
NAD manufactures an integrated amp (370) and a stand alone power amp (270) which is simply the power amp section of the 370. In this case, it would be perfect for bi-amping.

Now, I'm not intimately familiar with the Musical Fidelity line, but if they manufacture a separate power amplifier that exactly matches the A3.2's power amp, you should be fine. All the gain and power math will have been done for you.

In any case, being all four channels would be identical, you would probably be better off using both channels of one amp for each side. i.e. bass and mid/highs from one chassis.

Bass can draw a lot of power and having one amp providing the bass for both channels could strain the amp. Having only one channel per chassis handling the bass will afford a little more headroom overall.

Mind you, unless that power amp is an exact match for your integrated's power amp, like the NAD example, all bets are off

lumiere
04-02-2004, 03:34 PM
Thank you all for your answers. I'm still considering my options, and your help has been great!

Miguel

Mash
04-02-2004, 04:32 PM
Topspeed is correct: don't bother bi-amping unless you are mixing amps to obtain better sound quality: tube amp(s) in midrange/treble, solid state for bass and maybe a servo-feedback sub or two for sub-bass. This summarizes my (tri-amp) main system.

The basic bi-amp/tri-amp food-chain is
[source]-to-[preamp_out]-to-[crossover_with_level_controls]-to-[amplifiers].

So you will need a way to connect a [crossover_with_level_controls] between your MF A3.2 "preamp-out" and the MF A3.2 amp stage input. Unless the tape monitor loop comes AFTER the preamp-out (which I doubt) I do not see a very bright future for your project. But if you are considering only SS amps, why bother anyway? I run a MF A2 on MMG's in the bedroom and it answers the mail.

Remember KISS.