The Marchand have really good specs, along the lines of the dbx units. The BSS are more expensive than I can afford right now. I'm leaning towards the dbx 234 since this system will probably be a 3 way. The issue for me is whether or not it's worth it to have an electronic crossover between a horn midrange and a horn tweeter @ 5kHz. The tweeter takes so little power, and I don't know how sensitive I am to that frequency (since I have high frequency hearing loss - can't hear much above 10kHz). The tweeter is the B&C ME10/DE10 compression driver. The midrange is something else entirely. So, I may just get an analog 2 way stereo unit for my first crossover... I've never had one before so this is all new to me. So, I may get the dbx 223.
I did buy a used Crown D75A amp yesterday for $250. Since they sell new for a grand, I thought that was a good deal.
I did buy a used Crown D75A amp yesterday for $250. Since they sell new for a grand, I thought that was a good deal.
It is hard to say what is worth and what not.......my experience is that if you want to control the sound which means cut frequency phase .....limit.....little eq it......and so on than digital filter for each separate speaker shows absolute advantage.....and if you want to readjust it easily ...... but of course it is expensive...
I find this thread......it will maybe help you...
http://www.diyaudio.com/forums/digital-line-level/199741-diy-digital-crossover.html
Best regards, Taj
I find this thread......it will maybe help you...
http://www.diyaudio.com/forums/digital-line-level/199741-diy-digital-crossover.html
Best regards, Taj
P.S.
Don't get ma wrong.....I love analog stuff, tubes, transformers, big bulky heavy power amps......, vintage compressors.....but not for crossovers. Good passive crossover is great thing but it is hard to calibrate it.......when you choose active filter than go with good quality digital one. It is worth every single dollar, euro, pound......When I bought my first BSS it was like completely new sound system....everything was clear nice controlled.......like completely other sound system. Again I can't tell you how much I recommend good digital filter to you...
Very best regards, Taj
Don't get ma wrong.....I love analog stuff, tubes, transformers, big bulky heavy power amps......, vintage compressors.....but not for crossovers. Good passive crossover is great thing but it is hard to calibrate it.......when you choose active filter than go with good quality digital one. It is worth every single dollar, euro, pound......When I bought my first BSS it was like completely new sound system....everything was clear nice controlled.......like completely other sound system. Again I can't tell you how much I recommend good digital filter to you...
Very best regards, Taj
There of course can go wrong.....most common mistake is to connect tweeter to the wrong amp....for an example to the amp which plays subs.....if you mess up cables. The other thing is that you can destroy tweeter by setting fut frequency too low. It is good idea to connect capacitor in series with tweeter anyway to prevent the damage from the first case. But calculate it lower than cut frequency because you don't want to have phase problems around the cut.....
But don't be afraid. Modern digital crossovers have really good limiters and you can protect the speakers really well. I drive Beyma CP850/nd drivers with Carver PM950 amps. Only one driver per each channel.So the amps are way oversized... In past 5 years when those speakers were new I did't destroy any of them and I have 16 of them 8 per side. And of course I push them hard when it is needed. I use cut frequency which maybe seems quite high for 2'' drivers which is 1,6KHz but matching 15'' speakers allow me so.
Again don't be afraid to use good active crossover only be careful what is connected where and how it is set.
Regards, Taj
But don't be afraid. Modern digital crossovers have really good limiters and you can protect the speakers really well. I drive Beyma CP850/nd drivers with Carver PM950 amps. Only one driver per each channel.So the amps are way oversized... In past 5 years when those speakers were new I did't destroy any of them and I have 16 of them 8 per side. And of course I push them hard when it is needed. I use cut frequency which maybe seems quite high for 2'' drivers which is 1,6KHz but matching 15'' speakers allow me so.
Again don't be afraid to use good active crossover only be careful what is connected where and how it is set.
Regards, Taj
I have really large planar dynamic tweeters. If I connected the subwoofer amp to them the room would just get a little warmer.
You always set up and test quietly first...
Doing pro PA we always had seperate limiters after the crossovers. We'd set them during the real performance to just a bit more than the live program material. But that wasn't to protect the horns (field-replaceable diaphragms) it was to protect the performers so that feedback was never ever much louder than the performance (in case the feedback-destroyer automatic filters fail or some fool swings the mic into a monitor). One really bad squeal leaving all the artists temporarily deaf and the show kinda goes downhill from there...
You always set up and test quietly first...
Doing pro PA we always had seperate limiters after the crossovers. We'd set them during the real performance to just a bit more than the live program material. But that wasn't to protect the horns (field-replaceable diaphragms) it was to protect the performers so that feedback was never ever much louder than the performance (in case the feedback-destroyer automatic filters fail or some fool swings the mic into a monitor). One really bad squeal leaving all the artists temporarily deaf and the show kinda goes downhill from there...
Yeah, and they need such a small amount of power, particularly in a 3 way system where the tweeter is only for really high frequencies. If I can work out a passive crossover for this compression driver tweeter I think I'll use it. I have other ideas cooking of course, so this may be a series of changes instead of just a set system.
For domestc use hi-fi use I think you don't need any active crossover ..it can be done passive. But for a pro, live sound.....applications there is no space for passive filters. At least not in FOH systems. There you can still find some passive filters in stage wedges or some smaller speakers...
For an example. I can feed over 200W in my compression drivers...without any damage but I must cut them under 1,5KHz.....and limit them well. And I can do it very easily by using FDS366 which has excellent limiters at each output with adjustable speed and overshot.....
http://profesional.beyma.com/ingles/pdf/CP850ND.pdf
It depends what we are talking about. If about small soft dome tweeters than this is probably wrong forum because such tweeters are not common in Live Sound/PA Systems
Very best regards from London.....it's sunny...mmmmm
Taj
For an example. I can feed over 200W in my compression drivers...without any damage but I must cut them under 1,5KHz.....and limit them well. And I can do it very easily by using FDS366 which has excellent limiters at each output with adjustable speed and overshot.....
http://profesional.beyma.com/ingles/pdf/CP850ND.pdf
It depends what we are talking about. If about small soft dome tweeters than this is probably wrong forum because such tweeters are not common in Live Sound/PA Systems
Very best regards from London.....it's sunny...mmmmm
Taj
For domestc use hi-fi use I think you don't need any active crossover ..it can be done passive. But for a pro, live sound.....applications there is no space for passive filters. At least not in FOH systems. There you can still find some passive filters in stage wedges or some smaller speakers...
For an example. I can feed over 200W in my compression drivers...without any damage but I must cut them under 1,5KHz.....and limit them well. And I can do it very easily by using FDS366 which has excellent limiters at each output with adjustable speed and overshot.....
http://profesional.beyma.com/ingles/pdf/CP850ND.pdf
It depends what we are talking about. If about small soft dome tweeters than this is probably wrong forum because such tweeters are not common in Live Sound/PA Systems
Very best regards from London.....it's sunny...mmmmm
Taj
I would agree if we are talking about 4th order LR crossovers, which has many parts in a passive arrangement, but for those who wish to use compression drivers at home, their impedance is complex and makes a passive crossover difficult. I had to get help in designing a 2nd order LR HP for my B&C DE250 because there was no way for me to compute the LCR notch filters required to flatten the double impedance spikes at resonance for this driver. The ordinary second order HP LR filters would not work without a flat impedance curve. All of the LCR notch filter calculators that I could find required parameters that are not available for compression drivers. So, it would have made more sense for me to go active in this case I believe. Active crossovers also open the door to easy experimentation as well.
Apparently, one of the greatest benefits from active crossovers is that the amplifiers can provide maximum damping to the drivers, thus providing much better control over them. :
http://sound.westhost.com/biamp-vs-passive.htm
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I agree completely.....and there is some more benefits. Because 2'' drivers tends to shout arround 3KHz and are very unlinear it is easy to equalize them. And some digital crossovers have beautiful dynamic equalizers in their software...it is nice because such drivers become aggressive at higher levels but at lower tends to be without some real presence...and so on....
If you were somewhere closer I would lend you one of mine crossovers to experiment a while...hehe
Regards
If you were somewhere closer I would lend you one of mine crossovers to experiment a while...hehe
Regards
Thanks, that's very generous of you, but I am not nearly ready to use something like that. I haven't even finished the speakers yet!
if you can find one of these, they are really really transparent units...
the Marchands are also really nice units, and easier to get, as they are in production -- and Marchand will build you ANYTHING you want....
another option for good sounding vintage units are the older Pioneer Active crossovers, SF series and D23 units -- be aware the D23 units are highly collectable, and thus inflated in price... but they are excellent...
I agree that the BSS units are nice sounding also...
what do I use?
I'm kind of an oddball in this area, as I am using old very specialized clubsound (DJ) style crossovers from the likes of Richard Long and Associates (RLA) or Sound Environments INC -- they were basically used in custom club systems starting back in the late 70s...
I adore this sort of crossover, but many professional installers seem to HATE them....
some info:
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For this type of active analog crossovers my favorite for performance and cost is TDM.
TDM Audio Crossovers Equalizers and Compressors
http://www.tdm-design.com/acrobat/crossovermanual.pdf
I have seen these in several large Pas before digital was available at a reasonable price.
I have seen it many times for monitors where you need many, many devices for a dozen or more cabinets. Here is one on ebay
TDM 24CX-4, stereo 3 way/Quad 2 way electronic crossover | eBay
As for setting level to match use a MultiMeter and a CD with test tones.
If you can afford DSP you have some choices.
DBX Driverack
Behringer
XTA
After that things get pricey last time I priced things.
In the end it depends how much help your speakers need to “Sum Flat”.
I end up using horns and 12” that has to go higher then I would prefer.
In addition to High-Pass and Low-Pass I need to use Parametric EQs most of the time.
The cheapest way is then a DSP.
I do passive xovers for Pro speakers 90% of the time.
I have no trouble fitting in large complex crossovers in any box that houses a 12” or larger driver.
I can fit them in 8” most of the time, but a 5” gets tight.
Though 5” often needs less correction so it can work out.
Using a LCR notch is standard operating procedure on any typical horn/compression driver 1” to 2” throat.
If you have something you trust to measure output you can tweak in the notch by hand.
Multiply the value of the cap and inductor and write down the product.
You should see where the notch is cutting (If you are lucky). Change either the cap or inductor and see which way it went.
Once you have the center frequency you can work on the “Q” or width of the notch.
To keep it at the same frequency point the product of the cap and inductor must stay the same. So you can change one. Divide it into the product and you have a new Q to measure.
The last piece is the resistor. It is a volume control IOW how deep is the cut.
I can state all this easy enough, but it takes some serious time to do it.
I use LspCAD for modeling and Praxis to measure. Over $2k of software and as much hardware. A few years to figure out the program LOL
It really helps if you can measure impedance magnitude and phase.
A great combination is a simple active analog crossover to do the High-Pass and Low-Pass.
Then figure out the passive notch to flatten the horn out. This is inexpensive and works as well as a DSP.
NOTE: Make sure you use a high wattage resistors, 25watt at least and use combinations to go as high as 100watt.
For the inductor 18gauge or bigger.
For the cap 400volt
Like you said, small stuff is for 1” dome tweeters, not pro PA.
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