Low qts, high Bl, 6.5" / 7" drivers

[Leffemannen]

Hello folks,

Im looking for good 6.5 / 7" mid/bas drivers to go in a ML TL box.

What I really want is a 6.5 / 7" polyprop driver (or some sort of soft coated paper cone) with a qts = ~0.33 - 0.22, fs = 32 Hz (or less) and a Bl around 8 N/a. If someone know of anything remotely close to this please let me know.

This is going in to an old project that have ben constantly modified for about a year now. (Pic is hear: http://home.swipnet.se/Karlssons/speeker/frontside.jpg)

(Today it uses 6.5" HDS (plug'ed) driver's that Im just not getting happy with, not that it sound bad at all, in fact it's fantastic to acoustic music as well as trans and modern club music, but no mater what thins like Black Sabbath and good old Iron Maiden sound a bit "boring" and flat, and Im blaming that on the HDS sky high Fs and Qts)

I have looked at SS 7" kevlar diver, and in many ways it's just what I want, except what its a kevlar unit... And I am a bit skeptical about using kevlar in a 2 way. (I really do not want any "hard" or "cold" sounding mid range, or shouldn't I worry about that? Im very capable of dealing with it's nasty brake up from a XO point of)

Best Leif

[jomor]

exactly the ss 8546 was in my mind when starting reading your post. I ve experience in a two way with 8546 and the mids are great (as long as the phases of both drivers are matched of course). No funny cone break ups or anything. Very easy to filter and roll off. Bass is also great.

[MBK]

SS8543 is polypropylene... and cheaper than 8545/8546

[Tomac]

Monacor SPH-170c seems as a good value, for about 75 euro you get BL of 9.44, Qts of 0.26 and Fs of 38Hz. It is carbon cone, but it has no breakups,well at least if is to believe manufacturer's specs.
SPH-165 kep is even cheaper, has a Fs of 30Hz, Qts of 0.31 and BL of 7.6 . Drawback for you could be that it is kevlar cone.
Monacor also has one interesting speaker with polypropylen cone SPH-176, BL of 7.7, but Fs is higher than you wanted (39Hz) as Qts is, too (0.37)
Well, either they have different cone material from one you wanted,or their specs don't match to ones you aked for.
Well maybe if you want to pass cheaper than Scanspeak and can live with kevlar cone, SPH-165kep could be a good value for money. I haven't used it, but ones who did, say only good things about it.
I hope I was of some help

[Leffemannen]

Jomor, MBK:

SS8543 should be just about it, Im asking around for a price (no one here in sweden seams to have it in stock). Can't believe I missed that one on SS home page.

Tomac: Monacor drivers are interesting, but a bit hard to get around here, we'll see.

Thanks,

Leif

[argofanatic]

I've been looking at the Extremis 6.8

Looks like a perfect match for the parameters you're looking for.

[Audiophilenoob]

Originally posted by argofanatic
I've been looking at the Extremis 6.8

Looks like a perfect match for the parameters you're looking for.

beat me to it... it was made to beat the SS 8545 also

[jomor]

Originally posted by Leffemannen
Jomor, MBK:

SS8543 should be just about it, Im asking around for a price (no one here in sweden seams to have it in stock). Can't believe I missed that one on SS home page.

Tomac: Monacor drivers are interesting, but a bit hard to get around here, we'll see.

Thanks,

Leif

Note (by checking the off-axis responses) that there is a small hidden cone break up at 3Khz and a larger one at 5Khz at the 8543. Besides the large spl bump at the midband may require an extra notch filter. Apart from that it seems quite promising!

At 8546 the first hidden cone breakup appears higher, at 4.5Khz, and the spl bump at the mids is smaller.

Please let us know how the 8543 sounds when you finish your project. I havent any feedback about this driver so i m quite curious.


Btw the prices in europe are almost the same (as far as i can see from www.riviera-acoustics.com )

good luck

[MBK]

Hi.

here some thoughts about the 8543. I haven't heard it yet, since mine are also back ordered from Madisound, promised to arrive in ca. 3 weeks.

There is not much material on the web on it, but there is an old long discussion I found over Google groups, where Lynn Olson speaks highly of it ("one of the best midranges period"). Find it here:

news archive

The original is from the mid 90's, which shows it's not a brand new design - then again it shares the motor with the usual suspects of Scanspeak.

Apparently, as well, it has been used in ProAc Response models in the past (I believe later replaced by SS85310.

And finally, the best real data, in an extensive comparison, here:

Mark K's tests

As you can see, extraordinarily low nonlinear distortion in the midrange, and comparable energy storage with the other high end woofers. In this test, the currently popular test-champions are the Seas Excel 18W and 22W. If you look closely, though, they stand out in just a few frequency ranges in the linear distortion department (energy storage). I have heard the Seas 22W in an Orion and yes, it is remarkable transparent - but I still can't quite figure out whether I liked this "hyper transparent" effect (my wife shared my opinion).

So here you have it - apparently a good bet, the rest boils down to personal tastes.

Let's see how we'll like it in reality

[Leffemannen]

Originally posted by argofanatic
I've been looking at the Extremis 6.8

Looks like a perfect match for the parameters you're looking for.

The T/s para. sure looks good. Very good. Re of 7.02 is real nice then running them in parallel like I do too.

But I've heard some bad things about them also (and some good too, that's true), and if you look at the frec. response it ripple's about 7 - 8 db from 200 to 1500 Hz and still it looks like it's very smoothed.

And no brake up = very soft cone? I don't know if this is good or bad.

The SS 8543 ripple's less but have a defined brake up, I think I like that better, but only just.

I would really like to see some of axis SPL measurement of the extremis. That should tell allot.

/Leif