I seem to remember an article presenting how to run a 3-way speaker with two amps per channel, without a passive crossover per se.
The principle was that a low pass was added to the bass driver at leatst 1 octave above its intended crossover point, and similarly a high pass on the tweeter (and I'd assume a LPAD to bring its effective sensitivity down) below its crossover point - and then the two could be run on a single amp channel with a suitable active crossover, with the trebble and sub signals mixed together..
Does anyone know where I might review discussion/article on this?
I had in mind there was a patent.
I do have multichannel capability but I also have a spare 2x4HD and a couple or stereo power amps.
Thanks!
The principle was that a low pass was added to the bass driver at leatst 1 octave above its intended crossover point, and similarly a high pass on the tweeter (and I'd assume a LPAD to bring its effective sensitivity down) below its crossover point - and then the two could be run on a single amp channel with a suitable active crossover, with the trebble and sub signals mixed together..
Does anyone know where I might review discussion/article on this?
I had in mind there was a patent.
I do have multichannel capability but I also have a spare 2x4HD and a couple or stereo power amps.
Thanks!
Lol - that was me too. What a bimbo!
Mind you I wasn't (and still am not) put off by the nay-sayers, many of who missed the point as far as I can see. After all, I have a 2x4HD. My current PC DSP can do 3 ways. I thought the most pertenent comment was on clipping but I don't listen very loud in general.
Mind you I wasn't (and still am not) put off by the nay-sayers, many of who missed the point as far as I can see. After all, I have a 2x4HD. My current PC DSP can do 3 ways. I thought the most pertenent comment was on clipping but I don't listen very loud in general.
Why? Thay seems to me to miss the point of DSP - largely.
It would mean the usual faff of trying to pick a slope and crossover point, and try to deal with the delay offset, and match the at-crossover sensitivity, and source components that may be useful for precisely that - and potentially only that.
Admittedly 'bigger picture' tonal issues and baffle step can still be done globally in DSP, but:
- no way to fix poor phase tracking at crossover
- can't really fix mismatched sensitivity etc
- can't easily choose to try a different crossover point or slope config <= this is a pain
- can't easily use a simple LR unless miraculously the effective origins are almost coincident
- the usual juggle of needing non-standard values vs keeping the number of components sane
That it is fixed and dependent on the driver pairing is painful and not what I want with DSP.
I would be hopeful that a generic 'cut lows below a sane tweeter' and 'cut highs above a sane bass' might even be somewhat independant of driver involved, especially since a sub/bass will have dictated cabinet geometry (and hence be a fixture) more than mid/tweeter.
One of my on-the-shelf tweeter pairs is ribbons, so I'd want at least a cap between it and the amps anyway, and for the same reasons as above I'd prefer it not to be part of the final crossover.
I do understand that its a compromise, but it seems to me that it could make life easier if it works ok. While my own case involves an existing 2x4HD, I could see that the balanced (and so 4 channel) minidsp Flex and 4 channels of nCore+, nilai, or purify might actually be a considerable cost savings. If you blieve that the midrange is the core of the system and where to spend money, it would seem to make sense.
If you speak here about an invention, you have already spilled "prior art" and have spoiled the possibility to get a patent. You need to keep you ideas secret to the general public if you have plans for a patent.
Then specifically, there are many solutions withe mixed active and passive filters so the probability that you have come up with something unique is slim.
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Then specifically, there are many solutions withe mixed active and passive filters so the probability that you have come up with something unique is slim.
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The US patent was granted in 1981, it has expired. I make no claims to invent anything, except perhaps to observe that it may be more useful with a DSP crossover than with an analogue active crossover, which is also less flexible/maleable, harder to do time alignment etc.
What is tyour point?
I doubt anyone on here has built one. Plenty will have done a passive small speaker with an active crossover to bass.
Perhaps I described it wrongly, I suspect on reflection that I did, but the original paper is now linked.
These components are not designed to participate in the crossover from bass to mid, or mid to tweeter. They do not need to be chosen specifically to participate in any matching of frequency or phase.
Rather the low pass (or high cut) is designed to protect the tweeter from bass energy, and the high pass (or low cut) is designed to stop excitation of the bass driver cone resonances. Apart from that, they are supposed to be out of the way. I wouldn't regard a capacitor in series with a ribbon to protect it from stray mains hum etc in an active system as part of the crossover, for the same reason.