Here is the proposition
One pre-amp with two sets of pre-outs
Four power amps set as mono blocks
One pair of bi-wire speakers
One pre-out to two power amps to drive the left speaker. One amp for the hi level connections, one for the low level.
The other pre-out to do the same for the right speaker.
Would it work? Will the two pre-out signals be out of phase? Will the speakers go pop?
Would it work with a different configuration?
Idle musings during a very quiet day at the office.
Bi-amping is fairly normal. Never seen it done with mono blocks, although that doesn't mean it can't be done.
Try it and report back!
Yeah,that should be fine. Four monoblocks would be expensive though.
Most power amps have a input connection and a load connection to daisy chain a second power amp off of
Like this:
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In this set up you only need one set of pre-amp outs from your pre-amp
Are you power amps proper mono-blocks, in that they have only one channel of amplification?
I've seen it done before so it should be fine but I've never done anything like it before so no actual experience.
How tight are the tolerances on the mono blocks? Is possible one can produce significantly more power than the others giving an unbalanced sound?
I used to do this with Rotel Monoblocks into some JBL SVA2100 - worked just fine.
They were epic speakers!
It will work - but if you're doing that you're not getting the full benefit.
Get an active crossover between the pre amp and the power amp, and lose the passive crossover in the speakers.
Then you use one channel of one power amp for driving the high frequency driver, and the other channel for the low frequency. Cue more power, lower distortion, better dynamics 😀
The power amps are Rotel RB 850s
I dont't think they can be daisy chained.
The pre-amp is also Rotel.
ericemel, what was your wiring setup?
Current setup is two amps running as monoblocks, one for left, one for right into bi-wired speakers
I've got some RB850s too - flick the switch on the back and follow the wiring instructions on the back (left channel only on each, use both red terminals I think).
You get the sexy little 'Bridged Mono' light to come on on the front that way too, which is nice. You need speakers that are 8+ ohms, though - each amp sees half the impedance it would normally.
Edit: Sorry, missed the last line. You can use a splitter to each amp, but I think you'll see less overall power.
Using an active crossover is the way to go if you fancy tweaking.
My setup was exactly as you described.
2 sets of pre-outs (ie 4 cables in total) each going to a single Monoblock and each of those wired to one of the 4 speaker terminals on a pair of bi-wired speakers
Did you wire the pre outs so one pair of amps was the left speaker and one the right?
or
one pair of amps did the HF both sides and one pair the LF both sides?
Suck it and see, basically.
Although the speakers are biwirable, the speaker designer may not have voiced the speaker using the biwire connection, so although it may be different it may not be as good.
Also, especially if it is an older speaker, the driver units may have idiosyncrasies that he will have compensated for in the crossover, and a simple active crossover may not actually be as good at the driver integration.
When biamping with passive crossovers you don't gain the headroom benefit of taking the LF voltage requirements away from the HF channels. I guess you gain in that you reduce the current draw because the crossover is mostly blocking that but I think most benefits of passive biamping are placebo effect...
I've done it for a friend - 4 x Bryston 7b's into some PMC MB2's, Worked really well - Jesus it was loud. Well worth trying with the Rotels. Also it's better to run long interconnects (van dammes are cheap and blue) and short speaker cables or maybe it isn't...
Did you wire the pre outs so one pair of amps was the left speaker and one the right?
or
one pair of amps did the HF both sides and one pair the LF both sides?
Not sure I understand what you are asking here.
One pre-out goes to MB and to LHF
One pre-out goes to MB and to RHF
One pre-out goes to MB and to LLF
One pre-out goes to MB and to RLF
I get that bit, but considering just one pair of pre-outs, did the two outputs go to two MBs to one speaker?
I would go with thooms. Bridge the amps and forget about bi-wiring or bi-amping. But then I'm one of those weirdos who thinks several hundred watts of transistor amplification produces a better more accurate sound than 3 watts of valve amp per channel. So clearly I'm not a hifi buff.
The Rotel amps have unbalanced inputs so a long run will on the input will be prone to noise pick up - keep the signal cable short if you can 😀
Amen on the Van Damme stuff, it's cheap, really bendy, and most of your music will have been through miles of it before it gets to you.
Listening to music > listening to distortion. I do own a valve headphone amp, though 😳
In terms of the active crossover, you'd need to look at the existing crossover - but most drivers will work well with steep slopes without notches / EQ'ing in the crossover. Measuring helps, though, you need to be prepared to fiddle - but it's as close to a free lunch as you're likely to get in HiFi - especially as you have enough amps already...
Thooms, I see you are in Glos the same as me.
Beer and cake available if you could pop around my place for some on site assistance.
Email in profile.
Ideally ditch the lot and buy a pair of active speakers that have a number of advantages over amps/speaker cables/passive amps.
Never done it myself but using 4 mono-blocks to bi-wire speakers is a set-up I've seen and heard - with Audiolab amps I think. Sounded pretty good anyway but was fairly expensive.
More commonly I've seen similar things done with 2 stereo power amps, which also sounded good. I've got an active crossover for my Naim system (it's specific for the speakers I use) that I bought ages back but haven't used as I keep meaning to get around to buying a 2nd matching power amp to do it.
Just wired it all up.
Sounds awesome. A noticeable step up from the previous two mono blocs.
Only through some stand mount speakers at the moment.
Hoping a good annual bonus will fund some second hand Kef floor standers.
Rotel RB850's, nice! I used to sell those, still got an RA850 preamp, into a pair of Crimson power amps, into a pair of Trio speakers on Foundation stands.
Haven't used it for years, my t/table is on the fritz, and I can't be arsed/can't afford to get it seen to.
One day, perhaps.
CountZero, I think your not far from me, I have a turntable you could borrow as a stop gap if you want. Email in profile.
Further update.
Setup is now connected to a pair of KEF iq90 floor standers.
OMFG!!
So detailed
So controlled
So powerful
So loud!!
Yet still so subtle!
Awesome with all styles of music.