2" affordable compression drivers

[usa_satriani]

Hey there.

I have been interested in 2" compression drivers that would not make me sell my car (so no TAD, no Ale, no Goto, ...).

I have two favourites :

BMS 4592ND

Beyma 850ND

Do you guys have any feedback on these drivers ? What is basically
The BMS is coaxial and does not need a tweeter, I have Fostex T90A which still could be used, but a passive crossover would not be easy because the efficiency is quite difference ?

I would like to build a tractrix or JMLC squared horn to go with.

Thanks, Greg.

[ScottG]

I'd avoid titanium drivers generally ("bright") - that removes quite a few possibilites.

Bert over at BD-Designs has been working with the BMS coaxial for sometime now - specifically on the crossover but also with some modest physical changes. (..and no, he does not provide information on either.) Obviously he likes them enough to use them.

Another possibility is from Radian:

http://www.radianaudio.com/products/...wC=2neo_driver

but they also have some lower priced drivers that are also reputedly excellent:

http://www.radianaudio.com/products/..._driver&viewI=

(this co. actually makes replecement diaphrams for TAD - yes aluminum replacing Be, and several on the HiEff. board of the Asylum have preferred the radian replacements).

Note though that even with a very well done horn, a larger format driver will suffer from "beaming" to a greater extent than a smaller (or a co-axial) driver.

You might also consider a commercial horn or waveguide. (DDS Horns generally, or Bert's for the BMS co-axial.)

[tinitus]

Hi, thanks Scott, that was very good information on the BMS 2" coax, allthough I know BDs ORIS I had overlooked that the ORPHEAN uses the BMS - but my guess is that the horn is a bit small at such low frequency

[usa_satriani]

Thanks for the replies.

So ok, the Beyma has a titanium diaphragm wheareas the BMS has a polyester one. The radian 950 PB does not seem to have a flat response or it's because of the horn they used. The 850PB has a much flatter response.

I am not against buying a horn if the price is fair (no $1000 wooden horn). I'll check the ones you talked about.

So for the BMS the problem would be to do the crossover as it it quite hard to get information about it.

Greg.

[usa_satriani]

Another thing :

I currently own Fostex FE208Ez in a front tractrix horn with a T90A in the center and JBL 2226H running from 40 to 300hz.

I really like the tweeter a lot. I guess a compression will be better in the mids, more energy and so on but what about in the upper frequencies ?

But at first I could use the BMS full range and then try some tweeters with active filtering.

[ScottG]

The response for all the drivers is highly dependent on the horn its coupled to (in effect - its not something I'd be particularly worried about).

A good passive crossover can be tricky - the easiest thing to do is go active with the Behringer digital crossover and some extra amplification.

This is the horn I'd recomend:

http://www.ddshorns.com/catalog.php?page=CFD2110Pro

The horizontal dispersion pattern is broad and this helps with reproducing realistic imaging and soundstage artifacts endemic to the recording. Looking at the dispersion pattern you'll notice 4 plots (lines) that don't match up with the others. The most deviated 2 plots (the 2 inner circle lines) represent the top octave response at 1/3rd an octave (decreasing) from 16 kHz. (i.e. the inner most represents 16 kHz and the secondary inner most line represents 1/3rd an octave below this - 13.333 kHz.) The other 2 less deviated lines represent from 630 Hz up - ONLY if you are crossing below 800 Hz should you concern yourself with these two lines and matching dispersion with your mid driver - the lower the slope the less you need to worry (with respect to matching dispersion). Note that you don't have to purchase two of these - you could always purchase 1 and then use that as a mould for two cement horns.. AND you could even add JMLC's radius edge flair to improve diffraction.

In your situation I'd prob. purchase the Radian.. and try-out a passive 1st order filter for the super-tweeter anywhere between 12 kHz and 22 kHz. (..and the pasive parts value will be cheap because the cap (if parallel) will be small.)

Consider some cheap transformer attenuators (transformer volume control 8 ohm 10+ watts) to lower the eff. of the drivers to match the rest of your drivers. Despite the effects of core hystersis, it works a LOT better than using resistance for padding down more than 3 db. (..most are stereo - just use one "leg" of the stereo volume control for the driver.)

[Pano]

Hi,
You've got some good choices there. The BMS drivers are well liked by many on the web. I've never heard them, but they sure get rave reviews.

Don't forget about used drivers. You can often find used JBL or Altec horns and drivers at good prices. I'm very happy with my Altec 811 horns and 806 drivers. You may be able to find them or something like them for less than the cost of the new stuff. And if you don't like them, they are easy to resell.


BTW, I used to live in Toulouse - not too far from the airport. On the north side of town in the section called "les Minimes". A very long time ago. Cool town, Toulouse!

[danielm]

You might try the X-tealth 2000 2" driver.
Best driver I have found for under $100.

I believe it is a B&C DE-750 clone.

We've used them in a large line array.

[Pano]

Are the X-Tealth drivers made by P.Audio?

[Salas]

Thumbs up ScottG! Excellent recommendations and links.