If you're using a stereo power amp with the integrated amp, you use standard analogue interconnects from the preouts on the integrated to the inputs on the power amp, and speaker cable from power amp to the bass input terminals of the speakers - having first removed the 'jumper' links on the speakers.
If using monoblocs with an integrated amp, it's the same, except the left and right channels for the bass are in separate boxes.
If using a preamp with two stereo power amps - or indeed four monoblocs - you run interconnects from preamp to one stereo power amp, or pair of monoblocs, and then interconnect cables from the left treble amplification to the left bass amplification, and the same for the right channel. Most power amps have 'dasiychain' preamp-level outputs to facilitate this.
If you have triwirable speakers, you can do the same, but with two stereo power amps plus the integrated, or three stereo power amps (or six monoblocs!) run from a preamp. In each case a separate run of cable goes from each amp channel to the appropriate inputs on the speakers.
Take your time to set all this up, and check and recheck connections are all correct, and with no shorts, before firing up the amps. Getting it wrong can give a horrid sound at best, and damage to speakers and/or amps at worst.
Yes, you could use two stereo power amps in that configuration, just using the 640 as a preamp, and Y-adapters at the power amp end to enable on channel of the 640A to feed both channels of the power amp. But the more established way is to use one power amp for the bass and the other for the treble, so that the demands of heavy bass notes don't impede the treble. Or you could use another 640A purely as a power amp, using it together with the one you already have to biamp as I have already described.
would it not amplify the sound and send it tho the next power amp to be anplified further?forgive my ignorance and curiosity please
Daisy chaning them? you will achieve zero extra power handling because that is always limited by your final output stage (power amp2) What you will achieve, however, is the gain of your 'power amp seciton' will be the multiple of both power amps. That is all this would achieve and is a waste because at the end of the day all it will do is halve your 'usable volume knob arc' ** and not give any benefit in audio clarity. In fact, the extra circuitry will probably hurt your quality.
** I wish to petition for the use of 'usable volume knob arc' as an official technical term
I hope I'm not breaking any forum rules by resurrecting this thread! If so..My humblest apologies!
I currently have my 2 NAD 2200PEs power amps switched as mono and am using one to drive the left channel and the other the right. i belive this is a 2 monobloc set up?
Would I benefit by bi amping them instead in terms of obtaining the ultimate sound from my amplification setup? e.g. switching them back to stereo and using one for Tweeter HF and the other for Bass LF. I realise I will lose power but but at best, in current monobloc configuration, can only turn my preamp to between 8 & 9 oclock without going really, really loud, so should have plenty in reserve.
I think if I do this I will need a Y interconnect lead but am concerned that having too many connections will degrade signal from pre to power amps? Unless you can suggest a good quality Y cable that makes one connection. 1 male to 2 male about 1metre long?
The answer is that there would not be any benefit at all. You get no more headroom and since the tweeter does only about 5% of the work, the amp is wasted.
There have been lots of debates about bi-wiring and bi-amping and science says it doesn't help. Going active does.
In a two-way speaker system about 95% of the energy comes from the bass driver and 5% from the tweeter, so it's not really making life much harder for a single amplifier. In a big three way speaker about half the work is done by the Mid and tweeter and the other half by the bass driver so, if you had amps that were struggling to produce enough current but not volts, then there may be a benefit in using one to drive the bass and the other for the mid and treble. They would have to identical gain so best to use two the same.
I've heard that if you disconnect the passive crossover first the sonic benefits are massive.Is that true? Reluctant to do this though so I was hoping horizontal or vertical biamping (retaining the passive xover) would be worthwhile. I can't see this being worth 1200 smackers for another power amp though, so maybe i'll leave it as it is.......