Polypropylene coned drivers

[cs]

I have always liked the smooth sound you get with polypropylene coned woofers, such as those used by Spendor, for example.

Does anyone know of a source for such drivers, for DIY use ?
A size in the range 15 to 17cm would be ideal.

[alan-1-b]

Look on Monacor's web-site.
They manufacture drivers with cones of various types, and of good quality,
including some drivers which are designed to replace some of the ones in the better quality vintage l'speakers.

Visaton may be making some also.

[DDF]

The Scan 8543 is the best poly I've heard or used. I have years experience with it. If you like poly, you won't be dissapointed with this one.

[martinbls]

Hi DDF!

Can you share some of your experiences with the Scan Speak 8543 in regards of suitable tweeters and crossover-design? I'm a huge fan of simple first order x-overs. Is the 8543 capable of that?

Regards!
Martin

[DDF]

Originally Posted by martinbls

Hi DDF!

Can you share some of your experiences with the Scan Speak 8543 in regards of suitable tweeters and crossover-design? I'm a huge fan of simple first order x-overs. Is the 8543 capable of that?

Regards!
Martin

Hi Martin,
For Poly, it is somewhat stiff. This gives it good detail but also shows up as a high q resonance around 5 kHz. Because of this, and after trying over a dozen iterations, I felt it wanted an RC electrical second order + RLC series shunt for the peak.

In a 10"wx18" high faced box (driver center 7.5" from bottom), it measured as attached at ~ +5 deg vertical. You can see the break up requiring the trap.

I think this was used in the Pro-ac response 2s in the early 90s. I bought the woofer in '91 and used it for ~ 10 yrs.

Markk measured it here and found the midrange distortion "remarkable". I still like the 8545 better but this driver has a special place for me since its very smooth and has a nice "dark" but detailed sound when worked correctly.

7 inch driver test results

For tweeters, I would recommend your favorite soft dome. I think an Usher9950 or Dayton RS28F would be good bets. I ran it with a Scan 9300 but this was almost 15 yrs ago and I'd favour more modern tweeters over it now.

Dave

[DDF]

Weird post editor here at DIY, it blew out the attachment. Here it is again.

[martinbls]

Hi Dave,

thanks a lot!
Looks like the 8543 is not as smooth as other polycone drivers, so a bit more work on the crossover might be on the to do list...

Martin

[jmsent]

Have a look at the SEAS U18RNX/P.

THE ART OF SOUND PERFECTION BY SEAS - H1571-08 U18RNX/P


It's a woven poly cone, with very linear and extended response.

[crazyhub]

Originally Posted by jmsent

Have a look at the SEAS U18RNX/P.

THE ART OF SOUND PERFECTION BY SEAS - H1571-08 U18RNX/P


It's a woven poly cone, with very linear and extended response.

I agree, I used it in my last speaker; furthermore totally able to be used with a 6db slope because of the well-damped cone break-up. In french language but you can see some measurements of this speaker here:
VOKALIST monitor 2-voies: ça y est, elle chante!!! - Enceintes

CSD (at -40dbs !) of the U18 without filter, very clean:



.frd of the wave-guided 27TDC and (bellow) the U18, without filter but on the Vokalist enclosure; the slight dip around 2.5khz is enclosure diffraction related:

[DDF]

crazy hub, can you please repost these? They don't seem to want to expand, for viewing