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bi-amping questions
i have a few questions about bi-amping, and if its any help, bi-amping from a receiver that has the capability to bi-amp with the front/surround back terminals.
first off, how much power is actually going to the speakers when they are being bi-amped. if it was a receiver with 130 wpc, is it 130 watts to the lows and 130 to the mid/highs? or is it a little less, as if it were just a 4 ohm speaker (~250 watts)?
also, i know seperate amps are always going to be better, but would you guys shy away from bi-amping from a receiver?
asking because a pair of fronts i want can take 50-200 watts, and i dont want to put too much power, yet still want to bi-amp. i know more power is better than less, but i would like to find a sweet spot of power with a pair of fronts and the receiver im bi-amping from.
(talking about an onkyo 805 to be powering kef's iq9's)
thanks
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What's your objective?
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Originally Posted by adam mcd
i have a few questions about bi-amping, and if its any help, bi-amping from a receiver that has the capability to bi-amp with the front/surround back terminals.
first off, how much power is actually going to the speakers when they are being bi-amped. if it was a receiver with 130 wpc, is it 130 watts to the lows and 130 to the mid/highs? or is it a little less, as if it were just a 4 ohm speaker (~250 watts)?
also, i know seperate amps are always going to be better, but would you guys shy away from bi-amping from a receiver?
asking because a pair of fronts i want can take 50-200 watts, and i dont want to put too much power, yet still want to bi-amp. i know more power is better than less, but i would like to find a sweet spot of power with a pair of fronts and the receiver im bi-amping from.
(talking about an onkyo 805 to be powering kef's iq9's)
thanks
Why do you want to bi-amp?
- Do you just want more power than your receiver can deliver?
- Do you want to power the low and high frequencies with amps of a different character? (E.g. lows with at 500 w/c professional amp and highs with a 30 w/ch tube amp)
- Do you want to eliminate the speakers' passive crossover networks? (This will require that you by-pass the speakers' internal crossovers and insert an active crossover between your preamp and two stereo amps.)
If you simply want more power, you will likely be as well or better off just single amping with a more powerful power amp driven from your receiver's pre-outs.
Also, bear in mind that, for a given listening level, there is no such thing as too much power, although more power will not necessarily sound better, depending on the actual amplifier.
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well i always thought that bi-amping brings out the best in the lows and the mid/hi's. i just dont want to clip the speakers with too much power but im thinking that would only happen at too loud of volumes.
what i really want to know is what is the effect of bi-amping a speaker in relation to imepedence. does it make a 4 ohm speaker or does it double the amount of 8ohm power?
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The exact effect
Quote:
Originally Posted by adam mcd
well i always thought that bi-amping brings out the best in the lows and the mid/hi's. i just dont want to clip the speakers with too much power but im thinking that would only happen at too loud of volumes.
what i really want to know is what is the effect of bi-amping a speaker in relation to imepedence. does it make a 4 ohm speaker or does it double the amount of 8ohm power?
Broadly speaking bi-amping per se doesn't alter the impedance seen by the amplfier apart from the fact that the low-ranger drive might have a different impedance characteristic than the high-range driver(s). (Note: that bridging an amp to run it mono is a different matter: in this case the impedance is exactly half what it would otherwise be, e.g. 4 ohms instead of 8.)
Let me repeat: don't be concerned about having too much amp power -- clipping is caused by driving the amp, (not the speaker), past its power capacity, hence a more powerful amp is less likely to clip. Or if you like, for a given listening volume, a more powerful amp is "safer" than a less powerful one.
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Quote:
Originally Posted by adam mcd
i have a few questions about bi-amping, and if its any help, bi-amping from a receiver that has the capability to bi-amp with the front/surround back terminals.
Basically if it's helping then you're probably driving things too hard to be healthy anyways. What you're proposing is technically "passive bi-amping" which is not the same thing as true bi-amping.
Quote:
Originally Posted by adam mcd
first off, how much power is actually going to the speakers when they are being bi-amped. if it was a receiver with 130 wpc, is it 130 watts to the lows and 130 to the mid/highs? or is it a little less, as if it were just a 4 ohm speaker (~250 watts)?
Keeping in mind that the power ratings for your receiver are not 130watts/channel when you're using multiple channels, you are essentially making whatever power is available (lets say that it's 130watts just to be uncomplicated) to each of the driver sections. But, the speaker's woofer section is drawing at least 85% of the amplifier power, so when you disconnect it from the mid/tweeter section you still have a maximum usable power increase of only about 15% (~20watts). Beyond that, you'll clip the woofer's amp. 20 watts at that power level is way, way, way below any audible difference. That said, you do have a theoretical increase in dynamic headroom. That's very theoretical... you'd never approach a situation where you could actually hear it. Bi-amping does not affect the impedance at all.
Quote:
Originally Posted by adam mcd
also, i know seperate amps are always going to be better, but would you guys shy away from bi-amping from a receiver?
Hogwash. Want to trade me a Denon 5805CI for some entry-level Rotels? I'd be happy to purchase my half of that deal. Your subsequent system of course wouldn't even survive comparison, but hey... you'd have separates. There are no absolutes.
Quote:
Originally Posted by adam mcd
asking because a pair of fronts i want can take 50-200 watts, and i dont want to put too much power, yet still want to bi-amp. i know more power is better than less, but i would like to find a sweet spot of power with a pair of fronts and the receiver im bi-amping from.
Since you're unlikely to ever use more than 5 or 10 continuous watts of power, the "sweet spot" is pretty obtainable with any equipment in the world. You have nothing to lose by bi-amping the surround back channels if you'd like to and there is a tiny theoretical gain so if you've got the spare wire then go for it.
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