Hi there
Bit of a basic question I’m afraid, but cannot find the answer.
If I’m Bi-amping an amplifier which has two channels, 125W @4ohm each, does each lot of 125w go to each channel evenly?
IE- 125W to the woofer and 125w to the tweeter?
Or does the crossover I create mean that I get something like 200W to the woofer and 50W to the tweeter?
If the former is correct this would seem to waste loads of power.
Thanks!
Bit of a basic question I’m afraid, but cannot find the answer.
If I’m Bi-amping an amplifier which has two channels, 125W @4ohm each, does each lot of 125w go to each channel evenly?
IE- 125W to the woofer and 125w to the tweeter?
Or does the crossover I create mean that I get something like 200W to the woofer and 50W to the tweeter?
If the former is correct this would seem to waste loads of power.
Thanks!
If your amplifier is rated 125x2, it won't be able to do 200x1 and 50x1. Is your crossover active or passive? If passive, then the voltage out of each channel will be identical (the current will differ due to the crossover and driver impedances). If it's active the voltage out of each channel will be different, as will the current. But if music were calling for, say, 1/4 the power to your tweeter as it is to your woofer, it's more like 125x1 and 31.25x1. Of course that's a very crude estimate. Need more details of your system to get any more precise.
There's a lot less power needed at higher frequencies, so the demands on the tweeter channel will be much less.
Depends on the music, crossover point, volume, and tweeter efficiency. But the amp could deliver full peak power
to the tweeter if demanded by the situation. Ideally each amplifier channel functions completely separately,
though the shared power supply can cause interaction between the channels.
Depends on the music, crossover point, volume, and tweeter efficiency. But the amp could deliver full peak power
to the tweeter if demanded by the situation. Ideally each amplifier channel functions completely separately,
though the shared power supply can cause interaction between the channels.
Am I not right in thinking, the idea of ‘bi-amping’ is implicitly using an active crossover to feed the two channels?
So not sure why the question about a passive crossover?
Although, I have been thinking of bridging the amplifier then feeding that through a passive crossover. But as time goes by and I discover more and more things I have to add on to make it work, it would seem sensible to just use a MiniDSP.
So not sure why the question about a passive crossover?
Although, I have been thinking of bridging the amplifier then feeding that through a passive crossover. But as time goes by and I discover more and more things I have to add on to make it work, it would seem sensible to just use a MiniDSP.
Yes, but then is the rest of that power then available to the woofer? Or do I simply waste that power?
I see what you mean, but for my purposes that is wasting amplifier power, which costs.
Some use a lower power, lower cost amp for the tweeters (for home use). Even a single ended tube amp.
The gain of the two amps would be adjusted so the woofer/tweeter sound levels match.
The gain of the two amps would be adjusted so the woofer/tweeter sound levels match.
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Yes, but some do still use the speaker's passive crossover instead, just split into two sections for two amplifiers.
Many speakers are built that way, with removable jumpers on the back to separate the crossover sections.
That approach is much less effective, though.
Actually I know, for example KV2 audio use class D for the low frequencies and class A/B.. so presumably they are doing something like that.
My understanding is it depends on the amplifier topology. If the power stage is a big toroid, then yes you have power capacity that you're not using. However some people recommend that having lots of headroom is good for treble, because that helps ensure it can produce transients with minimal distortion. So if you have one channel doing bass at high duty cycle, and another channel that isn't putting too much stress on the power stage and is doing mid/hi at lower duty cycle with ample headroom - this might be a good combo.
All depends on the amp in question, the material you're playing through it, the crossover frequency of your speakers, and the sensitivity and impedance of each driver etc. I think this needs assessing in context, rather than trying to derive a rule that can be applied across the board.
Disclaimer, my knowledge is minimal and I'm not an engineer like some on here.
All depends on the amp in question, the material you're playing through it, the crossover frequency of your speakers, and the sensitivity and impedance of each driver etc. I think this needs assessing in context, rather than trying to derive a rule that can be applied across the board.
Disclaimer, my knowledge is minimal and I'm not an engineer like some on here.
I presume you mean they have much less control in terms of processing? I would have thought if they are feeding line level signal through the passive crossover, then crossover would not produce much heat and therefore be quite efficient.
Was talking about a (high power) passive crossover between the amp and speaker.
Between the preamp and amplifier, an active crossover is most common, but it's also possible to use a (low power)
simple passive crossover, usually only 6dB though, which would of course not dissipate amplifier power.
I guess I should ask, then, how does the following idea sound:
I run the amplifier bridged (BTL) then feed a single (high power) passive crossover from that.
I was getting the feeling that this is a bit of a crack-pot idea, but if it works I might try it. I’m guessing it’s done on subwoofers sometimes.
Nothing wrong with that, and many also use a bridged amp for the entire speaker, one per channel.
What is your crossover point?
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1.2 or 2k. It depends on whether or not I can use this method. I have a suitable tweeter. 1.2 is very low, I know, but I have quizzed the manufacturer on this.
If you're going for higher sound levels, 1k will be too low for most tweeters. Maybe even 2k.
Is that a dome, cone, horn, etc?
Do you have two stereo amplifiers to use for this?
Is that a dome, cone, horn, etc?
Do you have two stereo amplifiers to use for this?
I’ve checked with the manufacturer that it can handle it.
1.2KHz 12dB/ octave and the woofer I’m using is a fairly low powered 10”.
There are actually a number of 1” compression drivers that can handle similar. Beyma CD-10, B&C De111, several of the Faital examples are 1.3Khz, and some BMS ones. Even on one BMS iirc it an 800hz minimum crossover point.
Plus, fidelity is a relatively low priority, what is important is cut and intensity, particularly on-axis.
I might go for a 1.6Khz crossover, but the manufacturer insists 1.2K is fine over a reasonable lifetime use.
1.2KHz 12dB/ octave and the woofer I’m using is a fairly low powered 10”.
There are actually a number of 1” compression drivers that can handle similar. Beyma CD-10, B&C De111, several of the Faital examples are 1.3Khz, and some BMS ones. Even on one BMS iirc it an 800hz minimum crossover point.
Plus, fidelity is a relatively low priority, what is important is cut and intensity, particularly on-axis.
I might go for a 1.6Khz crossover, but the manufacturer insists 1.2K is fine over a reasonable lifetime use.
I’m going for the B&C DE111
I was considering the faital pro HF100 (I already own one). I was incredulous at the stated 2KHz minimum crossover point, considering it’s only a tiny 1” diaphragm, but again, they insisted it had been designed to cope with it.
I was considering the faital pro HF100 (I already own one). I was incredulous at the stated 2KHz minimum crossover point, considering it’s only a tiny 1” diaphragm, but again, they insisted it had been designed to cope with it.