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Compact 15" sub - BMS or Precision Devices? - Click HERE for Original Thread
DIAR
I'm about to build a small 15" subwoofer. The sub will be sealed with ~40 litre internal volume (Qtc=0,577). Any comments on this?

I can't deside which driver I should choose. The two best candidates are:
BMS 15N840v2 (~300€)
http://www.bmspro.info/photos/bmspr.../15N840v%B2.pdf

Precision Devices PD1550 (~200€)
http://www.precisiondevices.co.uk/showdetails.asp?id=14

The reason why I like these drivers is
high Bl
low Mms
reasonable Xmax
low Le (PD1550?)
power rating
availability


Both drivers seem very good for the application but I haven't found any comments on these drivers on the internet.

Le of the BMS driver is exceptionally low which is good. Unfortunately PD doens't give Le value for PD1550. How important low Le value is for subwoofer ?

Any comments are more than wellcome :)

Edit: I forgot to mention that I will be using the subwoofer for movies and music. I have DCX2496 for equalization and XO and Tapco J1400 PA-amplifier (2*310 w/8ohm).
pinkmouse
The PD is an excellent driver, but I think the BMS would be better for your small box. It has significantly lower Fs, and to get the PD to match would need lots of EQ, eating up your Xmax.
DIAR
Pinkmouse,

I guess you misread something.

PD1550: Fs=31 Hz
BMS 15N840v2 Fs=35.6 Hz

They both fit nicely to a ~40.5 L box (Qtc=0.577)

Since it is only the 15" driver that makes the sound there is no difference in output level/excursion. Actually they both give the same output in similar boxes so there is no difference in the need of equalization or excursion.

There is a slight difference between the drivers if put to a vented enclosure.
pinkmouse
Indeed I did. I somehow read the BMS as 25.6 Hz. I need another mug of tea obviously! ;)

Well, I can't comment on the BMS, as I have never heard it, but I know that the PD is a very good driver, take that as you will.
DIAR
The BMS driver looks too good to be true. On the other hand I don't know anything about BMS either. BMS specs might very well be BS :xeye: Atleast there is an error in Le (uH instead of mH) but the value is still very (too?) good.

Have you heard PD1550 somewhere?
pinkmouse
Lots. I used to work in the pro audio business, and I know a couple of Turbosound designers.
DIAR
Fantastico :D
I will go for PD if nobody has any info about BMS. Thanks!
Puggie
I have some BMS compression drivers, they are nicely made and sound fantastic. I have a PD2150 sub and its well made and should (when I get it in a proper box) sound fantastic. I have no experience with either specific product but I have experience with both companies' products and they are well made good quality stuff. I doubt either will dissapoint you.

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