Tweeter response looks like just one speaker measured.
100-200hz looks bad too if measured both.
but i still envy if thats listeningspot room response
https://www.youtube.com/watch?v=Sex97-hdK-Y
here you go aatu, test song for you
100-200hz looks bad too if measured both.
but i still envy if thats listeningspot room response
https://www.youtube.com/watch?v=Sex97-hdK-Y
here you go aatu, test song for you
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Of course that's not measured from the listening spot. That would look much, much more horrid. I have to make close-miked measurements in my living room in order to "see through" the room effects.
Sometimes I think I must be almost blind. I had been wondering why the image was badly tilted to the left. I had been measuring the right speaker and just copied its crossover modifications to the left one. Well, almost copied. For some unknown reason I had a series cap of 10µF instead of 4,7µF in the HP leg of the left speaker's crossover. And to think that I toiled away half an hour wondering why it behaves not the way I want. Then I looked at that black Solen cap: 10µF. No wonder then. Why didn't I notice this at once?
Sometimes I think I must be almost blind. I had been wondering why the image was badly tilted to the left. I had been measuring the right speaker and just copied its crossover modifications to the left one. Well, almost copied. For some unknown reason I had a series cap of 10µF instead of 4,7µF in the HP leg of the left speaker's crossover. And to think that I toiled away half an hour wondering why it behaves not the way I want. Then I looked at that black Solen cap: 10µF. No wonder then. Why didn't I notice this at once?
15CXA400Fe - Beyma
You are right, is very nice, even taking care of the 5.5K dip of the CD tweeter (HIGH FREQUENCY RESPONSE). Very smooth frequency response. OP has said he wanted only a one cone diaphragm based coax.
[PDF] 15CXA400Fe - Beyma
You are right, is very nice, even taking care of the 5.5K dip of the CD tweeter (HIGH FREQUENCY RESPONSE). Very smooth frequency response. OP has said he wanted only a one cone diaphragm based coax.
[PDF] 15CXA400Fe - Beyma
Attachments
Beyma 15CXA400Fe vs. B&C 15FCX76 - Very similar response mounted in enclosure (LF), freq. response wise with extension a little superior for the B&C (1-2dB's@30Hz). Also the 400W of Power, in enclosure /300W it all depends of Vb and tunning and sensitivity are similar. The B&C of the OP is also a great driver for a quarter wave or TL meriting a nice future project by bjorno (diyAudio Member)...
#141
#141
Sorry for my short absence here, have been a busy beaver building tube amplifiers.
There were no crossover plans provided. I think that the manufacturer has some kind of a generic crossover for this driver, but I'm not sure of this. Anyway, I'm really not interested in generic crossovers, since you should take your whole system in account when designing XO's.
The prototype in my living room is already starting to sound quite acceptable, but I haven't yet gotten the bigger boxes. The current ones are too small, only ~100 litres, limiting bass output.
About that Beyma, the response graph looks like it has some heavy smoothing...
B&C 15FCX76 has generic crossovers. It can always be a starting point and adjustments can be made as per the system. In high volume bass reflex cabinets responses will be far better. Depth of enclosure has to be more to have a glorious bass out of drivers. More the depth of enclosure, sound comes out with higher pressure from enclosures.
Please do not form any opinion without hearing them in right enclosure. B&C 15FCX76 is a good driver. Give it a proper breakin time and a good enclosure and it will sing.
Regards,
Gautam
Please do not form any opinion without hearing them in right enclosure. B&C 15FCX76 is a good driver. Give it a proper breakin time and a good enclosure and it will sing.
Regards,
Gautam
Do you mean that it is not just the net volume of the enclosure that is important. I mean that if I make an enclosure that is not so deep but a bit taller or wider instead that the (bass) response is different (also for other reasons than just front baffle size)? Does this affect all drivers or are there some drivers that need deep enclosures (like B&C 15FCX76 for example?)
Generally professional drivers sound better when the depth is more. of the two enclosures of same volume, the one which is more deep gives a better music and hearing experience. Coherence of music is better. Both the Beyma and B&C drivers with deep enclosure will always shine. generally large enclosures end up beating smaller enclosures. This is my observation.
Regards,
Gautam
Okay, time for an update. Just to show this project isn't dead.
The short version: not there yet, though nice sound can be had.
The longer version: The driver (B&C 15FCX76) now resides in a 180L bass reflex enclosure tuned to about 40Hz with 3 ports for adjustability. The crossover work is not yet finished, though it sounds quite nice already, apart from a slightly recessed upper treble (not going to post measurements this time).
Now, I've learned some things with this bugger. First lesson is that this kind of a box and crossover does need quite a low source impedance. At first I was ignorant enough not to even to try the 4ohm output of my tube amp, and that was a mistake. The 8ohm output gave this kind of separate bass response; measured response looked OK, but sounded separate from the midrange and high frequencies. Switching to the 4ohm output ultimately fixed this.
Now, the second lesson is that don't try straight front axis response with these drivers. Too bright. I'm still not finished balancing these things, but a straight front response does sound too bright and aggressive.
Ultimately, these are nice, but flawed drivers. And all coaxials are flawed, some way or the other. The midrange is surprisingly "see-through", and the bass can hit you in the chest. The treble range isn't bad, but balancing it to fit the rest is a slight challenge.
The reason I've not updated this thread for some while is that actually I've been just too busy listening. I've yet to strike the perfect balance, where you're supposed to just stop worrying. But I'm close, I think.
The short version: not there yet, though nice sound can be had.
The longer version: The driver (B&C 15FCX76) now resides in a 180L bass reflex enclosure tuned to about 40Hz with 3 ports for adjustability. The crossover work is not yet finished, though it sounds quite nice already, apart from a slightly recessed upper treble (not going to post measurements this time).
Now, I've learned some things with this bugger. First lesson is that this kind of a box and crossover does need quite a low source impedance. At first I was ignorant enough not to even to try the 4ohm output of my tube amp, and that was a mistake. The 8ohm output gave this kind of separate bass response; measured response looked OK, but sounded separate from the midrange and high frequencies. Switching to the 4ohm output ultimately fixed this.
Now, the second lesson is that don't try straight front axis response with these drivers. Too bright. I'm still not finished balancing these things, but a straight front response does sound too bright and aggressive.
Ultimately, these are nice, but flawed drivers. And all coaxials are flawed, some way or the other. The midrange is surprisingly "see-through", and the bass can hit you in the chest. The treble range isn't bad, but balancing it to fit the rest is a slight challenge.
The reason I've not updated this thread for some while is that actually I've been just too busy listening. I've yet to strike the perfect balance, where you're supposed to just stop worrying. But I'm close, I think.
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Hmm, I seem to remember saying something about that originally.
The more directive it is at higher freq.s, the brighter it sounds - despite being counter-intuitive with respect to in-room power response. (..might want to re-relay that to your friend.)
As for your other problem, look to Impedance at Fb - and correct it:
Charge Coupled Crossovers Article By Jeff Poth
SuperQ Steel Core Coils | ERSE
Hmm, I seem to remember saying something about that originally.
The more directive it is at higher freq.s, the brighter it sounds - despite being counter-intuitive with respect to in-room power response. (..might want to re-relay that to your friend.)
And I might not even have completely disagreed. The question is where to tilt and by how much. And the "optimum" amount and point of tilt seems to vary between drivers. But yeah, ruler flat is really too bright.
But this isn't actually that counter intuitive. Since you basically have almost constant directivity from ~1kHz upwards, compared to a for example 1" dome tweeter you're going to have loads more energy in the room in the last two or so octaves.
But I'm making progress. Lazily, though, but still progress. It already sounds quite nice. But I won't be happy 'till it sounds addictive.
My main point of interest is still in electronics, so I've no use for active setups. I need speakers I can evaluate amps with in my main setup.
I do admit that some active or semi-active setups are quite spectacular. Some time ago I was lucky enough to get to listen to a pair of activated JBL 4345's. The lows were driven with a Lyngdorf amp and a Devialet unit acted as the crossover and was driving the midrange and high frequency units. And it did sound good. Good and ridiculously loud. You could literally play it so loud, that your head would shake, your vision would get blurred. And the sound would still be completely relaxed and controlled. I couldn't listen that loud for more than a minute or two, but good fun still...
I do admit that some active or semi-active setups are quite spectacular. Some time ago I was lucky enough to get to listen to a pair of activated JBL 4345's. The lows were driven with a Lyngdorf amp and a Devialet unit acted as the crossover and was driving the midrange and high frequency units. And it did sound good. Good and ridiculously loud. You could literally play it so loud, that your head would shake, your vision would get blurred. And the sound would still be completely relaxed and controlled. I couldn't listen that loud for more than a minute or two, but good fun still...
That makes sense.
Yes those JBL's are a source of inspiration for me. I'm running 2x18's per side. It really is hybrid pa/hifi system.
I did try ruler flat at first but it was definitely way to bright. I took down 2k-10k by 2dB. 10-16k has a 1dB drop. Sounds the most natural on a wide variety of recordings and genres.
Yes those JBL's are a source of inspiration for me. I'm running 2x18's per side. It really is hybrid pa/hifi system.
I did try ruler flat at first but it was definitely way to bright. I took down 2k-10k by 2dB. 10-16k has a 1dB drop. Sounds the most natural on a wide variety of recordings and genres.
Okay, small update. I spent a couple of evenings fiddling about with the crossover and this is where I ended up. The notch on the response at ~1,3kHz might be fixable, but I'm working in an iterative way, fiddling, measuring and then listening. The measurement is a close miked one, taken at ~50cm from the cone, so port response is absent - hence the bass looks weaker than it is.
Now, sound wise this is starting to be interesting. It still a little on the polite/soft side of things, but that might even be a good thing. The weird thing is that now that I got the midrange working, the bass sort of just popped into focus with the rest of the range just by itself. Previously it sounded a bit separate from the rest, now it's a solid part of the whole.
I quite like these now.
Now, sound wise this is starting to be interesting. It still a little on the polite/soft side of things, but that might even be a good thing. The weird thing is that now that I got the midrange working, the bass sort of just popped into focus with the rest of the range just by itself. Previously it sounded a bit separate from the rest, now it's a solid part of the whole.
I quite like these now.
