Bi-amp Question??

[Tom-Brown]

Having just got back into Hi-fi :) especially playing vinyl, I have been seeing different options in operating speakers. I now understand Bi-wiring speakers but I keep coming across Bi-amped?? How does one do this - I have a NAD C370 amp directly connected to my rega rs3's - How could I set up a bi-amp format - is it one amp per side??

[Desmo]

You will need 2 amplifiers either 2 the same (vertical bi-amping) in which case you use one per speaker, or two different amps (horizontal bi-amping) in which case you use one amp to drive the higher frequency drivers and one amp to drive the lower frequency ones. Vertical bi-amping is the easier of the two and sounds better in my experience.

[Tom-Brown]

You will need 2 amplifiers either 2 the same (vertical bi-amping) in which case you use one per speaker, or two different amps (horizontal bi-amping) in which case you use one amp to drive the higher frequency drivers and one amp to drive the lower frequency ones. Vertical bi-amping is the easier of the two and sounds better in my experience.

So do I connect the individual amps to my main amp via the speaker outputs for each side then speakers connect via the two additional amps :)

[Hudz]

If you can get hold of a C 270 as the other amp in your bi-amp setup both amps can be run as monoblocks, thus allowing you to drive each speaker separately with 300 ish watts of rather good quality juice at the flick of a switch on the back and a quick reconfigure of your speaker cables.
just remove one of the pre-power links on the back of the c370 and connect that to the other amps input(left if i remember correctly but please consult the manual as its bin a while since i owned these )and switch both to mono as both amps have identical power amp sections Manual is here http://nadelectronics.com/products/hifi-amplifiers/C-370-Stereo-Integrated-Amplifier and for the 270 http://nadelectronics.com/products/hifi-amplifiers/C-270-Stereo-Power-Amplifier one click of a switch and a quick shift of speaker cables and you have two excellent mono power amps. Even better results can be had by using a better quality preamp and just using the power amp sections of both amps as IMHO opinion the pre on the C370 can easily be bettered but the power amp sections are quite good.
Or as posted above by Desmo you can biwire your speakers by utilising the spare set of preamp outs on the back of the c370 and connecting them to another power amp

[Audio Advent]

What one might normally do is have a pre-amp with two outputs and then have two identical stereo power amps connected to those.

With your integrated amp (which has the pre-amp and power amp in one box) it could be more complicated but NAD has already accounted for that! Yes, you attach a second stereo power amp to the second set of outputs on your C370. That second set also has a volume adjustment on the back if you can't find a second amp which matches yours for power/sensitivity etc. That's why it would be better to find something in the NAD range from the same era, like the C270 because it should give the same volume as your C370.

Often people find that it works best when you're running the bass drivers with a seperate amp from the rest. Hence wiring one amp to the bass and another to the mid/trebble (or whatever options you have on your speakers). I guess the advantage of that coupled with the volume control for the second output on the C370 is that you can turn the bass down late at night if you want..

[Audio Advent]

Sorry Hudz to correct you, but whilst running them as monoblocks is possible, it isn't anything to do with bi-amping. What you'd get instead is still just a stereo amp but with much more power on each channel.

Some people though say that bi-amping doesn't have much effect but running more powerful amps does!

Try it both ways and see what is best.

[struth]

I used to run my Arcam and Atoll bi amped horizontally. Worked very well. The Cambridge p500 *2 does vertical well. there is an in and out to connect them thus they act as monoblocks. I have one and there is one for sale here...still tempted to get it

[Audio Advent]

Monoblocks means each runs only a single channel (rather than a stereo channel each) - is that what you mean?

I guess with a second power amp with a volume control, one can also fudge it by connecting the second amp to tape outputs as long as the tape select is the same as your listening source. Although, bass from Radio 3 whilst mid/treble from a CD might well be an interesting sound! (If anyone reading is going to try that, please remember that the tape output will likely be full volume! Hence needing some kind of volume control on it or on the second amp)

[Hudz]

Sorry Hudz to correct you, but whilst running them as monoblocks is possible, it isn't anything to do with bi-amping. What you'd get instead is still just a stereo amp but with much more power on each channel.
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Some people though say that bi-amping doesn't have much effect but running more powerful amps does!

Try it both ways and see what is best.

I stand corrected:o i'll get me coat:)

To my mind utilising a c370/270 combination as monoblocks is better than bi-amping is what i was trying to infer

[montesquieu]

I stand corrected:o i'll get me coat:)

To my mind utilising a c370/270 combination as monoblocks is better than bi-amping is what i was trying to infer

I did some passive bi-amping experiments with various Tannoys. Waste of time, no benefit whatsoever. (Passive as in bi-amping into speaker crossover).

Active bi-amping (active crossover outputting frequency corrected signal to amp and then on to speaker) was a different thing entirely.

Had four 300b PP Audion monoblocks, tried both ways. Only the active approach had an impact.

I wouldn't spend money to experiment with this, try and borrow the extra monoblocks first.

[Thetiminator]

A lot depends on your speakers. If you have inefficient speakers you'll find more of a benefit with horizontal biamping (I've tried all the options over the years - single power amp, monoblocks, 2 monoblocks per speaker and horizontal biamping) ie one amp driving the bass and tother driving the hf's. When thinking about power to your speakers it's not about just the power.....

Your speakers may present different loads across the frequency range eg have dips in the bass. Mine have vicious dips in a couple of frequency ranges. If you power a speaker with one amp you are asking the amp to provide different currents at the same time. By driving say the bass with one amp, it's just driving the same load rather than differing loads and can work more efficiently. The benefits of this (in my experience are a more relaxed, natural sound with better dynamics and detail with a tighter, deeper bass.

[Barry]

This might be of some interest and help: http://theartofsound.net/forum/showthread.php?5818-Basics-amp-General-Bi-amping-and-Bi-wiring