BMS
Thanks for the quick replies! I guess if the 18N860 isn't released yet i'm not going to be able to get my hands on one - friends overseas or not
The reason i'm asking is because I'm trying to find the most suitable 18", lowest distortion, pro driver to go into a small box (95L). To use as either vented or sealed with a linkwitz/esp circuit to extend the lows to lower. With that in mind, I've been looking for drivers with the lowest: vas,qts,qes and highest: excursion,sensitivity,power rating.
the ones that I've modelled in winISD so far are the 18 sound: 18ND930, 18ND19300; B&C: 18NW100; Beyma: 118NDW; Precision Devices: PD1850, PDN18SB40 and the BMS 18N860.
The reason i was looking for the BMS driver is that out of all the above it has the highest excursion, and power rating.
Am i barking up the wrong tree?
The 18 sound drivers both presented quite well in winISD with a box of 95L - whereas most of the others prefer a box size of roughly 200L.
The neodymium magnet stucture isn't as high a priority, i was only going for those for the weight factor, (i don't want my mate lugging a 20kg driver in his suitcase if i can get away with it
Any pointers would be most welcome, i'm not so good at woodworking, otherwise i'd be building myself a horn as my first project! But i'm really comfortable with math/electronics so a linkwitz circuit is the easiest for me to start with
Someone recommended car audio subwoofers for their high excursion and power ratings, but they don't seem to be very sensitive - roughly in the 85db range...
Thanks for the quick replies! I guess if the 18N860 isn't released yet i'm not going to be able to get my hands on one - friends overseas or not
The reason i'm asking is because I'm trying to find the most suitable 18", lowest distortion, pro driver to go into a small box (95L). To use as either vented or sealed with a linkwitz/esp circuit to extend the lows to lower. With that in mind, I've been looking for drivers with the lowest: vas,qts,qes and highest: excursion,sensitivity,power rating.
the ones that I've modelled in winISD so far are the 18 sound: 18ND930, 18ND19300; B&C: 18NW100; Beyma: 118NDW; Precision Devices: PD1850, PDN18SB40 and the BMS 18N860.
The reason i was looking for the BMS driver is that out of all the above it has the highest excursion, and power rating.
Am i barking up the wrong tree?
The 18 sound drivers both presented quite well in winISD with a box of 95L - whereas most of the others prefer a box size of roughly 200L.
The neodymium magnet stucture isn't as high a priority, i was only going for those for the weight factor, (i don't want my mate lugging a 20kg driver in his suitcase if i can get away with it
Any pointers would be most welcome, i'm not so good at woodworking, otherwise i'd be building myself a horn as my first project! But i'm really comfortable with math/electronics so a linkwitz circuit is the easiest for me to start with
Someone recommended car audio subwoofers for their high excursion and power ratings, but they don't seem to be very sensitive - roughly in the 85db range...
Instead of focussing on 18 inch drivers, you could simply use multiple smaller drivers for the same output, which has the added benefit that you can scatter them around the room and get a better modal response for free.
tapped horns are quite easy to build, if that really is a concern and one tapped horn has about +12db max output (changes with frequency) compared to the same driver in closed box.
tapped horns are quite easy to build, if that really is a concern and one tapped horn has about +12db max output (changes with frequency) compared to the same driver in closed box.
Just for the record
BMS 18N860 is finally on the market
Not sure, but maybe mms have gone down a bit
The only source I know charges 600EUR each
New BEYMA 21" is 650EUR
FaitalPro 18" sub is 490EUR
PrecisionDevices PD2150/PDN2150 about the same
Seems to me the prices on PRO woofers are going up
Lets hope that means they are getting better as well
I will stick to ordinary 18" pro woofer
I prefer better frequency response, to make ordinary 3way active a possibility
BMS 18N860 is finally on the market
Not sure, but maybe mms have gone down a bit
The only source I know charges 600EUR each
New BEYMA 21" is 650EUR
FaitalPro 18" sub is 490EUR
PrecisionDevices PD2150/PDN2150 about the same
Seems to me the prices on PRO woofers are going up
Lets hope that means they are getting better as well
I will stick to ordinary 18" pro woofer
I prefer better frequency response, to make ordinary 3way active a possibility
I'm looking at a sub for my home system and was thinking of using a Phase Linear Aliante 12" unit. They are obsolete but still occasionally available. I have a 10" version in the car and it's superb. Flat GRP & aluminium honeycomb driven element , 5" voice coil , huge magnet , stainless steel frame and very high power handling.
Whats the opinion of using car sub drivers in a home system ?
Whats the opinion of using car sub drivers in a home system ?
Has there been published any measurements on pro woofers? Especially I would be interested to see graphs and/or hear user feedbach about PD186s. Hopefully by the end of the week my 8 x PD186s will arrive
The U-frame-line-array boxes, in which PDs will be intalled, are ready:
It also came to my attention that BMS has a very good woofer (18S430v2: http://bmsspeakers.com/fileadmin/bms-data/product_data/cone_drivers/other/bms_18s430v2_t_data.pdf) approximately in the same price class with PD186. Any feedback on these?
What comes to the demodulation/shorting rings, I think they start to play some role in the last couple of millimetres of the linear xmax.
I have a theory, based on which I think almost every producer uses shorting rings, otherwise the inductance would rise sky high in >3-inch voice coils...
For example in Eminence Definimax 4018LF is advertised about using a shorting ring, but still it's inductance is whooping 4,78mH and because of this the FR drops very soon, at approx 1kHz. Then the Kilomax 18, which has more xmax (and therefore longer voice coil), has only 1,59mH of inductance and an FR reching 2kHz but it's not advertised to include a shorting ring??? How else than with shorting ring would this be possible? There is no other way, Kilomax must have a shorting ring even though it is not stated...
So as a rule of thumb, I think one can deduct the usage and maybe even the number of shorting rings from the 1) lenght and 2) diameter of the voice coil. The longer the VC is and the more diameter the VC has, the higher the inductance should be without shorting rings. If a shorting ring is applied, then the inductance drops and if another shorting ring is applied, inductance drops some more etc...
If the inductance is not stated in the spec sheet, one can estimate it by looking at the frequency response of the woofer (and comparing it with same size woofers); the higher-reaching FR, the lower the inductance must be.
Therefore, if a long throw woofer (VC longer than 23mm for example) with a VC of 4 inch in diameter, has a FR that reches to the 2Khz or higher, it must have quite low inductance and therefore a shorting ring or two.
What do you think?
The U-frame-line-array boxes, in which PDs will be intalled, are ready:
An externally hosted image should be here but it was not working when we last tested it.
It also came to my attention that BMS has a very good woofer (18S430v2: http://bmsspeakers.com/fileadmin/bms-data/product_data/cone_drivers/other/bms_18s430v2_t_data.pdf) approximately in the same price class with PD186. Any feedback on these?
What comes to the demodulation/shorting rings, I think they start to play some role in the last couple of millimetres of the linear xmax.
I have a theory, based on which I think almost every producer uses shorting rings, otherwise the inductance would rise sky high in >3-inch voice coils...
For example in Eminence Definimax 4018LF is advertised about using a shorting ring, but still it's inductance is whooping 4,78mH and because of this the FR drops very soon, at approx 1kHz. Then the Kilomax 18, which has more xmax (and therefore longer voice coil), has only 1,59mH of inductance and an FR reching 2kHz but it's not advertised to include a shorting ring??? How else than with shorting ring would this be possible? There is no other way, Kilomax must have a shorting ring even though it is not stated...
So as a rule of thumb, I think one can deduct the usage and maybe even the number of shorting rings from the 1) lenght and 2) diameter of the voice coil. The longer the VC is and the more diameter the VC has, the higher the inductance should be without shorting rings. If a shorting ring is applied, then the inductance drops and if another shorting ring is applied, inductance drops some more etc...
If the inductance is not stated in the spec sheet, one can estimate it by looking at the frequency response of the woofer (and comparing it with same size woofers); the higher-reaching FR, the lower the inductance must be.
Therefore, if a long throw woofer (VC longer than 23mm for example) with a VC of 4 inch in diameter, has a FR that reches to the 2Khz or higher, it must have quite low inductance and therefore a shorting ring or two.
What do you think?
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IMO:
What comes top 18-inch models, too big inductance (no shorting rings apparently). In general, High inductance equals more upper bass distortion. No shorting rings, well... inductance and Bl varies much with voice coil's position = the woofer will distort more when it's cone moves compared to a woofer with shorting rings (in general).
Woofers also don't seem to have vented chassis. Air compression, whether in closed box or inside woofer's motor, raises 2nd harmonic distortion.
There are better option imo, for example BMS's woofers.
edit: RCF's woofers seem to have demodulation rings. Inductance is still quite high.
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This is a very interesting thread with much close debate by informed people esp. regarding horns (well, mostly informed). Glad it was resurrected.
Oddly, a great answer is from Tim in Edmonton in reply 2.
Funny, oddly absent is the basic issue for a speaker: what frequency range? No way to choose a driver or enclosure without nailing that down first and sticking with it.
Related to that, there is a very odd, and may I say, ill-considered, suggestion of a 5-way system. Having just been reading Toole for a month and puzzling why the two-way systems are so well liked, going to 5-way seems a good way to solve problems few have and cause problems with multiple cross-overs that everybody has.
And speaking of Toole, nobody can do a Big Job these days without a strategy for room response. In my view for home music, that inevitably must mean a couple of mixed-bass speakers in the bass room-response region below 80-100 Hz spread around the room because there may be no other feasible solution. Which leaves you naked to room-response in the 100-300 region, alas.
One of these days, we all need to think about power again. Not long ago on my scale of lifetime, sophisticated people (who owned meters and scopes) laughed at the power-hungry plebeians. Not sure what the word is today. Related to that is fussing over voice coil resistance changes with heat, brought up in this thread. Can't happen in any normal sized house I know of with any "regular" music.
Oddly, a great answer is from Tim in Edmonton in reply 2.
Funny, oddly absent is the basic issue for a speaker: what frequency range? No way to choose a driver or enclosure without nailing that down first and sticking with it.
Related to that, there is a very odd, and may I say, ill-considered, suggestion of a 5-way system. Having just been reading Toole for a month and puzzling why the two-way systems are so well liked, going to 5-way seems a good way to solve problems few have and cause problems with multiple cross-overs that everybody has.
And speaking of Toole, nobody can do a Big Job these days without a strategy for room response. In my view for home music, that inevitably must mean a couple of mixed-bass speakers in the bass room-response region below 80-100 Hz spread around the room because there may be no other feasible solution. Which leaves you naked to room-response in the 100-300 region, alas.
One of these days, we all need to think about power again. Not long ago on my scale of lifetime, sophisticated people (who owned meters and scopes) laughed at the power-hungry plebeians. Not sure what the word is today. Related to that is fussing over voice coil resistance changes with heat, brought up in this thread. Can't happen in any normal sized house I know of with any "regular" music.
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If you're looking for big high-power woofers with extended HF response, decent Xmax, and low distortion, then the AE TD18H+ is a probably a good bet -- only a 2.5" coil but well cooled, and lower inductance than any other 18" high-Xmax driver I can think of.
Ian
AE Speakers --- Superb Quality, Unforgettable Performance, Definitely.
Ian
AE Speakers --- Superb Quality, Unforgettable Performance, Definitely.
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Yes, this woofer is interesting; has isomeone measured it? What's the average THD% 90/95/100dB@1m and is there any plots which show the distortion behaviour?
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