best 6.5'' aluminum driver

If I were you, i would stay away from metal cone drivers...... Look at that response, almost 20 dB difference between 4k and 10 kHz.. You must be a real expert in filter design to handle that kind of response. Really it is not much useable above 1.5-2 kHz. I've suffered a lot with similar drivers before I gave up on them (Fountek FW168, Seas metel cones, etc.) For the same money you can get excellent 6.5 inchers that are much easier to work with
 

AJ34

Member
2012-07-18 6:28 pm
If I were you, i would stay away from metal cone drivers...... Look at that response, almost 20 dB difference between 4k and 10 kHz.. You must be a real expert in filter design to handle that kind of response.

Agree if you're talking about passive speaker design but surely an active design using DSP would easily cope with such imbalances:

Product Concept | miniDSP

If you haven't seen it before, scroll down and check out the demo video - impressive stuff and invaluable for the DIY'er (as if better audio quality alone wasn't a good enough reason to go active).
 
Well, the problem is, that all DSP processors try to correct a deficiency with another one, even the best ones... Whatever you do with such kind of resonace peak, somehow it will always come through, ruining to overall presentation of music.. at least that's my experience. A decent paper cone (pulped, reed, or sliced cone) will always give a much more musical reproduction of the original source, no matter what you do. I think your best bet is one of the sliced cone Revelators, Illuminators, or the incredible 6.5 inch Satori woofer from SB Acoustics. But of course it depends on your expectations......
 
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AJ34

Member
2012-07-18 6:28 pm
Whatever you do with such kind of resonace peak, somehow it will always come through

I haven't yet used DSP in an active speaker crossover so I have no practicle experience. I suppose though, even if measurement indicated a flat frequency response after DSP, a driver that's been heavily EQ'd could 'sound' different at it's frequency peaks - maybe due to higher distortion?
 
Unfortunately there are a lot more things that determine the overall sound quality, than a flat freqency response.. DSP-s alter the phase, and group delay characteristics of the signal, (that's the way they work) -even though they do it do it digitally- not to mention the fact, that the signal goes through over a zillon of semiconductors, so the end result will be pretty far from musical. Of course this is a personal opinion, based on my demands for faithful music reproduction. Your mileage may vary.... :). But keep in mind, the less (active) components in the signal path always mean better sound quality.
 

burnett

Member
2007-10-09 11:40 am
For my ears, and taste the only metal cone driver equipped speakers that sound really good, are the Sonics Anima-s bx Joachim Gerhard (Ex- Audio Physics designer), but then again, it uses a custom made woofer by Seas, so it is not easy to reproduce.

Sonics Anima loudspeaker | Stereophile.com

Custom made? Just the typical hifi-fairytales.

[IMGDEAD]http://img4.audio.de/image-r721x960-C-3c3dc616-12968785.jpg[/IMGDEAD]
 
I've had a good look at some of the metal cones, and none of them are easy.

Amongst the 6.5" units, I found more pleasure in the paper, reed and polypropylene units, because that metal cone breakup is a bitch to deal with. I preferred the look of these two SEAS units allied with soft domes:
SEAS ER18RNX Reed Cone
SEAS U18RNX/P Polycone

There is an exceptionally nice 5" unit that behaves much better than comparable conventional 5" cones. The Visaton AL130 Metal cone.

Visaton publish some designs for it like this Bijou. Very nice indeed, albeit not cheap. Vented magnet is always good, but it's the flat power delivery that makes it unique and it has less breakup horrors than most. The ceramic KE25SC tweeter is exceptional too, with built-in Fs correction.

I would quite fancy that driver with some of the better SEAS metal tweeters like these too:
H1283-06 22TAF/G
H1212-06 27TBFC/G

It's a fact that you will discover, that it is best to not mix materials with speakers.
 
Why would that be so?

Pretty easy really. All drivers have an acoustic signature related to what they are made of.

If you use drivers with similar characteristics, they exhibit faults related to the standard resonances. For instance most paper drivers and soft domes fall apart around 7 and 12kHz. The best you can do is align them so they are equally bad and the Q's (or damping) match. That way, your ear hears no glaring difference.
 

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Anima
This is the new Anima with improved cabinet and crossover. You can read a report in the new Stereophile by John Atkinson.
Sure, the drivers are standard and i am not responsible for the sales blurb.
We test each driver though for linearity and distortion. SEAS made a lot of improvements in quality control over the years including the use of Klippel so very few fail.
The know how that i think i have is in the crossover. You really have to suppress the break up peak but also reach a rolloff that makes the blending of the tweeter smooth.
I think the teeter breakup is too high to be audible. You have to consider that a soft dome breaks up too more or less controlled at a much lower frequency. If you measure it the right way a rigid membrane has less distortion and better resolution. Of cause the magnet and suspension plays a big role too.
 
Well, the crossover is 3rd order acoustic butterworth. Both, in phase and out of phase sum to unity on the design axis. The out of phase has lower phase distortion and the in phase has better lobing to the top.
Atkinson critisized the lobing beheviour so i fixed it with doing the tweeter in phase. Gave me a new and better review .
Is that too pragmatic for you ? I have no day job you know.