Compression Drivers. Please Share the experience.

0 Members and 1 Guest are viewing this topic. Read 6354 times.

Jon L

The topic of compression drivers seems to fly under the radar, and despite the limited number of people who seem knowledgeable, very few audiophiles actually seem to use speakers based on compression drivers at home.  Googling doesn't yield much info, especially any recent developments. 
Due to richidoo's generosity, I've got my first pair of compression drivers in house (Radian 475PB), and I do believe they deserve far more attention. They sound VERY nice driven by my 300B SET.

0401201954_1585856903981 by drjlo2, on Flickr

The most info I could dig up was some old threads in DIYAUDIO some 13 years ago  :o
https://www.diyaudio.com/forums/multi-way/114481-horn-compression-drivers-music.html

If there have been significant changes and advances, please do share your experience here.
Here's a quoted text from above DIYAUDIO thread where "Daveis" compiled a collection of comments from many people:

========================================================

I scanned through some threads.
Can anyone add to this list of recommended horns?

B&C DE250
Radian 745/950pb 745P
Beyma CP25 CP380 CP380M
BMS 4540 4592nd neo 4540ND
JBL Alnico 2482
18 sound ?
TAD 2001

==============================

Radian 745 1.4 in. CD'

2NDA520

Radian 950pb with the BMS 4592nd, and the Radian plays in a other league.

jbl 2405

Brient had the TAD 4001 to compare with - he sold the TAD, and kept the Radian,

Instead of the JBL slot - look to the Beyma CP25

BMS 4540 tweeter going down to 1KHz,

used both small and large format BMS drivers and have to say they really aren't my idea of high fidelity.

Beyma CP380 LINK They sound better than the big dollar TAD's to me.

CP385/Nd.

love those 755Nds I got from you Duke.

distortion of the CP380M is practically negligible and predominantly 2nd order.

BMS neo compression drivers, and I think they are excellent. I would go so far as to say that they are all but unbeatable at that price range.

I've used Selenium, B&C, BMS, Radian and JBL. Here are my opinions, FWIW:

B&C: Great value for the money, great quality control. One of my favs.
BMS: IMHO their neo compression drivers are almost unbeatable. I think this is why JBL rebrands BMS drivers. Amazing sound and value.
Radian: After hearing all the positive feedback on Radian, I bought a pair. They don't measure the same. Is this a quality control problem? I don't know, because I bought mine used. But I never bought another pair, and stick to B&C and BMS now.
JBL: Hideously overpriced. If you don't mind buying used, you can get amazing deals on Ebay. I have a set of Alnico JBL compression drivers which are to die for. I had to replace the diaphragms with Radian, but now they work great (and they match!)

only reasonable choices are:
BMS 4540ND
B&C DE250
Beyma CP380M

BMS 4540

Phenolic sounds good. I like JBL 2482 and Eminence APT series.

Other than the B&C I can recommend the TAD 2001 (expensive) or the Emilar EC175 (out of production / business) or any of the Radians. The 18 sound horns are very good! Maybe they have an inexpensive non-metallic diaphragm compression driver for them? The little BMS drivers are probably less collered than the Selenium because they are polyester.. The Beyma CP380 is VERY good

think you will like the DE10 and the 18 sound horn XT120

FWIW, the stuff I have to work with:
Lambda TD15X ( I have 3 due to a shipping accident, may get another soon)
JBL 2123H
BMS 4540ND
DDS ENG 1-90

Radian 745P 16 ohm:
2125hz -6db LR 24

Freo-1

Re: Compression Drivers. Please Share the experience.
« Reply #1 on: 6 Apr 2020, 08:45 pm »
I think these make a lot of sense for low wattage applications.  I admit my knowledge of these is lacking, but the few I've heard were rather impressive. 

guf

Re: Compression Drivers. Please Share the experience.
« Reply #2 on: 6 Apr 2020, 11:46 pm »
other than having them I don't know anythin about it  :duh: I had to look to see if they were compression. They are I have the B&C  DCM-50 on my modified Klipsch horns. I just got them because its was the most suggested.  I only use a 45 tube to power them.

Jon L

Re: Compression Drivers. Please Share the experience.
« Reply #3 on: 7 Apr 2020, 05:56 am »
They are I have the B&C  DCM-50 on my modified Klipsch horns. I just got them because its was the most suggested.  I only use a 45 tube to power them.

B&C DCM-50 seem to be 2" compression driver, so it will go lower than 1" compression driver like the Radian but not as high.  So you must have a separate tweeter in your Klipschorns. 

I'm really liking having just one compression driver cover from 1kHz and upward.  After getting used to this sound, going back to conventional box/cone drivers seem almost syrupy and blurry, although compression driver is pretty unforgiving and naked sounding of poorly recorded material. 

I'm hoping somebody can nudge me towards other 1" compression driver/horn combo that retains the clarity but maybe just a tiny bit more forgiving and fuller sounding 1kHz and above  :thumb:

 


sonicboom

  • Jr. Member
  • Posts: 103
Re: Compression Drivers. Please Share the experience.
« Reply #4 on: 7 Apr 2020, 07:07 am »


I'm hoping somebody can nudge me towards other 1" compression driver/horn combo that retains the clarity but maybe just a tiny bit more forgiving and fuller sounding 1kHz and above  :thumb:

 

You can try the old Altec AlNiCo 802D / 802G CD's mated to a 32A or 32B horn. They are a bit pricey but not too crazy, although certainly more than the SEOS and Radian you're currently using. The Emilar EH500 and EH800 horns are also very good but are also more rare. As an aside, there's some connection historically between Altec, Emilar and Radian.

The 32/802G combo has no discernible horn coloration and sounds smooth.

http://jelabs.blogspot.com/2018/02/altec-32a-32b-emilar-eh1210-eh800-eh500.html?view=magazine

Here's another build based on the JE Labs two-way


JLM

  • Full Member
  • Posts: 10654
  • The elephant normally IS the room
Re: Compression Drivers. Please Share the experience.
« Reply #5 on: 7 Apr 2020, 11:40 am »
Have heard several compression drivers over the years and owned JBL 708P active monitors that use 2409H in a waveguide.   Cheaper ones can sound rough, but no complaints with the better ones.  Their biggest problem is finding bass that can keep up with them in terms of dynamics, speed, output, and detail. 

ric

  • Full Member
  • Posts: 360
Re: Compression Drivers. Please Share the experience.
« Reply #6 on: 7 Apr 2020, 01:54 pm »
I would call Clayton, owner of Spatial Audio. See if you can get a hold of him as he is an expert. Good luck!

mocenigo

  • Jr. Member
  • Posts: 12
Re: Compression Drivers. Please Share the experience.
« Reply #7 on: 7 Apr 2020, 04:22 pm »
Have heard several compression drivers over the years and owned JBL 708P active monitors that use 2409H in a waveguide.   Cheaper ones can sound rough, but no complaints with the better ones.  Their biggest problem is finding bass that can keep up with them in terms of dynamics, speed, output, and detail.

True. This was the problem to solve with my speakers. B&C makes some midrange drivers that have good sensitivity and match quite well to their coaxial compression drivers. So the designer chose that. Then at the lowest end the choice fell on a Dayton Audio PA 18" speaker - with 97Db sensitivity.  Similar stuff available from Faital, for instance. Using the lightest ones (they will burn if fed more than 400W, but we are speaking of low wattage) they are very fast, almost do not move at all (little distortion) and detailed. Cover only 2 1/2 octaves or so, like 20-120 Hz. Closed enclosure, and a series cap on the xover input - if you do not want to use a plate amp. Then this should work and not break the bank. The large inductance in the filter may cost as much as the large woofer :-)

eso

Re: Compression Drivers. Please Share the experience.
« Reply #8 on: 7 Apr 2020, 04:45 pm »
I've been a low power SET amp/high efficiency speaker guy for 20 years now. Done badly, stay away... But done right nothing comes closer to the real thing IMHO.

For me it started in 2000 with the purchase of a pair of early '50s Altec A5s. While certainly not the last word in frequency extension, they were/are wonderful and have a huge, open, relaxed presentation that you could listen to without fatigue all day and night.

I then built my own 3 way system using vintage JBL drivers (D130 in a folded midbass horn, 2440 one custom molded tractrix horns) and Fostex horn tweeters. That system served me well for 15 years.

I'm nearly completed with what should be my last upgrade to Cogent field coil compression drivers for mids and mid bass along with my Fostex tweeters. This system also big built-in folded 30Hz bass horns for the bottom octave (All of that weird wood work behind the speakers is the bass horn mouths)

System sensitivity >110 db 1w/1m

While it can play cleanly at painful levels, I don't usually do that. listening in the lower 80db range it's got incredible transient response and micro detail. The speakers really do not seem to be the source of the sound: I just get a life size stereo image that seems independent of the equipment around the room.

eso








Jon L

Re: Compression Drivers. Please Share the experience.
« Reply #9 on: 7 Apr 2020, 06:12 pm »
I'm nearly completed with what should be my last upgrade to Cogent field coil compression drivers for mids and mid bass along with my Fostex tweeters. This system also big built-in folded 30Hz bass horns for the bottom octave (All of that weird wood work behind the speakers is the bass horn mouths)

I would love to own some field coils  :thumb:  The cost and effort gone into your system is highly impressive!

If I win the lottery and a bigger room, I would love Some Avantgarde Trio's of Cessaro Gamma's  :lol:




Jon L

Re: Compression Drivers. Please Share the experience.
« Reply #10 on: 7 Apr 2020, 06:13 pm »
Trio's




cft

  • Jr. Member
  • Posts: 3
Re: Compression Drivers. Please Share the experience.
« Reply #11 on: 4 May 2020, 08:55 am »
You can try the old Altec AlNiCo 802D / 802G CD's mated to a 32A or 32B horn. They are a bit pricey but not too crazy, although certainly more than the SEOS and Radian you're currently using. The Emilar EH500 and EH800 horns are also very good but are also more rare. As an aside, there's some connection historically between Altec, Emilar and Radian.

The 32/802G combo has no discernible horn coloration and sounds smooth.


How is this vintage combo compared sonically to modern waveguide  +driver these days, for instance, QSC clone with Beyma CP380m, etc ? :)

cft

  • Jr. Member
  • Posts: 3
Re: Compression Drivers. Please Share the experience.
« Reply #12 on: 4 May 2020, 08:58 am »
Incidentally, Beyma cp380m reportedly being used in the Trio above IIRC. :D

Jon L

Re: Compression Drivers. Please Share the experience.
« Reply #13 on: 8 May 2020, 01:44 am »
Incidentally, Beyma cp380m reportedly being used in the Trio above IIRC. :D

Hmm, $180 compression driver used in 6-figure speakers..
I am working on some Avantgarde-style 1" round horns currently.  Perhaps I should give the Beyma CP380M a try.   :icon_lol:

Jon L

Re: Compression Drivers. Please Share the experience.
« Reply #14 on: 25 May 2020, 09:15 pm »
Finally put together the round horn system with same drivers, and there is quite bit of difference between Seos12 rectangular horns and round horns, which are made out of thick fiberglass and glued to wooden mounts.  Rectangular horns "control" vertical dispersion well, but the round horns do not change sound much when I stand up or sit on the floor, with overall more airy, live sound.  Sounds incredible, actually  :green:

0525201114 by drjlo2, on Flickr

nickd

Re: Compression Drivers. Please Share the experience.
« Reply #15 on: 25 May 2020, 10:22 pm »
While I only have experience with Altec and JBL compression drivers, what I have heard is nothing short of revelatory. In my younger ignorant audiophile days I thought all horns were colored and would shout. No so if implemented correctly with well designed crossovers.

There are down sides. You need big efficient woofers. Great Plains Audio, JBL, Eminence, etc.

You also end up with a big speaker and they really don’t do sub bass so count on using very fast subs to complete the package.

Big, kind of expensive, not to wife friendly in the looks department and usually hard to crossover so you need a pro like Danny Ritchie to help in that department. If you can swing all that, you can have a very addictive speaker. A good set of Altec’s (or similar DIY) will make a regular “audiophile” speakers sound broken. The vintage tone and lifelike dynamics are just not available in the showroom of your local retailers.

rajacat

  • Full Member
  • Posts: 3239
  • Washington State
Re: Compression Drivers. Please Share the experience.
« Reply #16 on: 25 May 2020, 10:27 pm »
I built a set of speaker using the SEOS 18 waveguides, BA750 CD and AE TD15M woofers. The thing I like about the SEOS 18 is that I can cross it over @~750hz so it matches up well with the BA750 which BTW, are still available. I believe its the only 1" CD that can go that low.My rig is presently using a TPA 3116 for the tweeters and it's sounding very good. I'm attenuating them with Fostex R101T's. Aside from attenuation, I'm letting them run free range and bringing in the woofer @~ 700hz.
 The SEOS 18/BA750 handles the 700 hz cross rather easily. Just using the adjustable LP and HP filters in the  Crown. I'm running the AE woofer within the zone where it's flat and @ ~80hz crossing to twin 6" kit Anarchy folded horns which are HP @ 30hz for protection. I also have a 12" traditional sub and may soon add another (RSL Speedwoofer).

   The rectangular WG fits my room well because I have deal with a low (7'-8") ceiling. I'd like to try a large round WG that could go a low as the SEOS 18 but it's sounding great presently. It's amazing the quality of sound I'm getting from the humble TPA 3116. However, I'm presently looking for tube amp to replace the 3116's for evening listening sessions. I generally run the amps all day so the little 3116' are good enough for that.  I've thought about tilting the speakers slightly upwards to get a higher image. However, presently they're sounding sweet indeed in the sweet spot. Also looking for a tube amp for the compression drivers


« Last Edit: 25 May 2020, 11:37 pm by rajacat »

Jon L

Re: Compression Drivers. Please Share the experience.
« Reply #17 on: 25 May 2020, 11:40 pm »
That BA750 CD is a monster at 10 Lbs! 

Where did you buy the Seos18 waveguide in the United States?  I can only find Seos10 or Seos12.

rajacat

  • Full Member
  • Posts: 3239
  • Washington State
Re: Compression Drivers. Please Share the experience.
« Reply #18 on: 26 May 2020, 12:05 am »
That BA750 CD is a monster at 10 Lbs! 

Where did you buy the Seos18 waveguide in the United States?  I can only find Seos10 or Seos12.

I bought it years ago when the SEOS thread over on DIY Sound Group started up. I was a participant in the first group buy. I think it was one of the first SEOS 18s delivered.
The 18 has slightly different proportions than the 12 or 15. A little deeper. The BA750 was designed to mate perfectly with the 18  .....if I recall accurately. Actually I might have the wrong way around. The 18's throat was designed to fit the BA.

dB Cooper