There is a lot of R&D that goes into an XO beyond crossover points, and after listening to my Elites active, I miss the warmth I perceived with the crossovers. I don't want to lose the passive EQing that the crossovers add to the Morel drivers and tweets, not to mention the protection.
So I talked to PG about BI amping and I'm not sure about the answer. I can separate the mid + from the crossover but the Tweet - and Mid - have to share a ground. I'm a little wary of connecting the neg speaker terminals from 2 different amps to the same point.
Can anyone confirm that this is safe for the amps involved? I have some extra Ti XOs, maybe I'll try it with a couple B/S amps.....
I would think that it would be hard because the x-over uses the impedence of the speakers to dictate the x-over freqs. If you start to try and take the x-over apart and move the speakers in the schematic I would think that it would also change the impedence and then the freqs and mess everything up. I have only bi-amped diamond audio hex 3-ways and they have a jumper that needs to be moved but it was designed for it.
The impedence of the cross-over is determined by the speakers, and that determins the freq. By basically disecting the cross-over and seperating the inputs you need to be carefull that you do not change the over all setup of the cross-over circuit as by simply adding or subtracing a wire you could change a series connection into a parallel connection or vise-versa and that could make a drastic change in the impedence, and the frequencies.
A good example is I had a customer that wanted to add a 2nd 6.5 inch woofer to his componants by simply connecting it to the woofer output on the cross-over that was already in use. This would mess everything up.
My only thoughts were that if it were as simple as just seperating the inputs don't you think there would be a easy way that they would provide to do this?
I understand what your saying, but the modification is at the beginning of the circuit, not the middle or end. I'm not messing with the impedance. If I was ignorant to the impedance changing the crossover point I would simply use my extra crossovers and run the tweets on one and the mids on the other. All thats being done is separating the Mid input from the Tweet input, so you can use two separate amps-Bi-amping. However as the crossover shares grounds through out the circuit, its easier to bridge the grounds from the amps. My question is do you think that would be potentially harmful to the amps?
cojones wrote: ...I would simply use my extra crossovers and run the tweets on one and the mids on the other.
Maybe I'm overlooking something but I don't see any issues with running two elite xo's in order to bi-amp your component set. Anyone with some insight care to straighten me out?
I understand that a crossover is ultimately dependent on the driver to determine the circuit's characteristics.
What I am uncertain of is if the midrange actually plays a role in the tweeter circuit or vice versa. I suppose I always just assumed it didn't but now you've got me wondering.
dedlyjedly wrote:I understand that a crossover is ultimately dependent on the driver to determine the circuit's characteristics.
What I am uncertain of is if the midrange actually plays a role in the tweeter circuit or vice versa. I suppose I always just assumed it didn't but now you've got me wondering.
It has been years since I studied them in school but that is what I thought. As I said it seems to me that if it were as easy as you were hoping that they would have made accomodations for it to be done, or given instructions on how to do it, or tech support would know how to do it. They use to give schematics for their tri-mode wiring on the amps even though not many people ever used them.
I talked to Glenn their Acoustical Engineer about it, he told me how to do it.
I'm looking for input about connecting the neg speaker terminals together. I don't feel safe doing it with out knowing the possible consequences.
As for Cojones' concern of having continuity between the grounds from 2 different amps, I understand that throws up a red flag. Not sure why the ground has to be connected? Never heard that one before.
As for your idea of warmth, have you tried using less slope on the P9's x-over points? ie 12 or 18 db/oct instead of 24? Also, just between me and you, I love the sound I'm getting by using analog x-overs now that I've sold my P9.
Glen showed me which coil to use for my mid + connection, but he said there were multiple shared grounds in the xo circuit so it was easier to use the ground input on the xo for both amps.
I don't suppose it would damage anything but I can't say I've ever tried such a thing. I guess my concern would be NOISE. And probably alot of it. I guess you'll just have to try it.
You should try using the amp x-overs and see if that helps get the sound you're looking for. It wouldn't take any rewiring and definitely wouldn't hurt anything. Just open up the P9 x-over range so that it's bigger then the range you dial in on the amps to be sure the P9's x-over isn't affecting the outcome. You may be pleasantly surprised. Personally, I'm becoming less and less a fan of digital x-overs.
poop! Well, you could always do as Jed suggests and use 2 x-overs. (the absence of 1 or the other driver will not effect the output of either highpass or lowpass.) Do you have spares? Or make your own based on that chart I linked.
