Passive bi-amping works ?

I used passive bi-amping and it was a slight improvement. I would suggest you go that route with the idea of eventually going to an active cross-over which will be a HUGE improvement. At least that was my experience. Active cross-overs are relatively cheap.

craig, i tink yule like yer bi-amped set-up, but as yuve also had yer amps seriously upgraded, i imagine lotsa improvement wood be evident even if using only *one* amp in a bi-wire mode.

supakit, whether or not 4 channel for passive bi-amping is better than bridging & having 2-channel w/bi-wiring, depends, in part on the power-requirements of your speakers. if, for example, yer bass driver/s really need 200w to come alive, & yer 4-channel amp is, say, 100wpc, then bridging the amps to two-channel, w/anywhere from 200-400wpc, will prolly be better. but, if each channel of yer four-channel amp is more than enuff power for the load it'll see in a bi-amped configuration, it will prolly sound better when run bi-amped.

hope this helps, doug s.

Thanks. Can you list some pre-amps which have 2 outputs ?

ryllau, there are many pre's that have more than one set of main output connectors. but, i woodn't necesarily use this as the criteria for choosing a preamp. there are quality adaptors that allow ewe to connect a pair of i/c's to one output. even tho my pre has *three* outputs, i still have to use adaptors, because i use an active x-over which has only one set of hi-pass outputs. i run a pair of amps from my hi-pass outs to wertically bi-amp my monitors.

but, when bi-amping, ewe *do* have to be even more aware of impedance mismatches - adding a second amp to yer pre effectively lowers the input impedence the pre is seeing. for example, if ewe are using two amps rated at 20k-ohms input impedence, the preamp will *see* a 10 k-ohm impedence. and, longer i/c's, which can be attractive in a wertically bi-amped set-up, to reduce the length of the speaker cable, can further exacerbate any impedance mismatches. basic rule of thumb is that yer amps' input impedance needs to be *at least* ten times greater than the output impedance of the preamp, & in some instances, even this amount may not be enuff.

hope this helps, doug s.

It only makes a difference, if you use different amps. If the amps are not underpowered, then two should sound essentially the same. If power was the issue, then significant gains can be had. I passively bi-amp, but with tubes on top, solid state on bottom.