EX-6.5 Now Available DIY

[Kevin Haskins]

Hey... thought I'd drop in here and let the speaker builders know that these are being sold as raw drivers now.

I spent some time on the documentation this morning. Let me know if you see any glaring errors.

http://www.exodusaudio.com/images/EX_docs.pdf

For an idea of scale, here is a driver next to the RS-180. Both are the same format driver but the motor of the EX-6.5 is dwarfed by the Dayton unit.

[Jed]

Kevin. How much do these Retail for and does your company have wholesale accounts for speaker companies?

Jed

[tktran]

$75. Nice price.

It would be nice to see some unsmoothed curves though. Warts and all.

[Scott Simonian]

Kevin, that is one sexy driver you have made there. Nice work!

I also felt a bit of nostalgia reading the .pdf file. Almost like I was back in 2001 reading about any particular Adire product.

[Kevin Haskins]

Kevin. How much do these Retail for and does your company have wholesale accounts for speaker companies?

Jed

Yea... retail is $75 and you would have to contact me off-line about wholesale. I do most of my wholesale stuff by the seat of the pants.

[Kevin Haskins]

$75. Nice price.

It would be nice to see some unsmoothed curves though. Warts and all.

There isn't much in that curve that is changed by 1/6th octave smoothing. The unsmoothed curve is identical but I've standardized on 1/6th for all my driver measurements.

I'm going through the entire lineup and getting FR & Z for the bigger woofers and the 1/6th octave helps cover some of their warts higher up in the FR range (the bigger woofers). As you move further out into the far-field many of the response issues even out also. I do most of my design measurements at about 1.5-2m because that is closer to what you are going to see at the listening position. If you try to equalize too much in the crossover (for near-field response issues) you end with poor results.

[Kevin Haskins]

Kevin, that is one sexy driver you have made there. Nice work!

I also felt a bit of nostalgia reading the .pdf file. Almost like I was back in 2001 reading about any particular Adire product.

I have some pictures of this next to the Extremis too. The motor on the Extremis had a little more stroke but if you look carefully, the EX-6.5 has a larger roll surround. Out near the limits that allows this driver to have a little more usable stroke but not enough to get excited about. We also give up some cone area because of the nipple so it's a push.

The balance of parameters though are such that the EX-6.5 doesn't need as much excursion capability. It is a smaller box driver and more efficient so it gives up some bandwidth to the Extremis. I like the tradeoff though and it goes plenty low in the ported alignments. Low enough in-room that many people at VSAC wouldn't believe me that I didn't have a subwoofer running.

[Quwiksilver]

Kevin, that looks awesome! Two of these in an open baffle anyone?

Is there any chance we could get Zaph to do some distortion measurements on this guy?

[mazurek]

This new driver of yours looks a lot like the B&C 6NDL38 I have (which I would give to Zaph to measure if he sends me a PM). I wonder how they would compare.

[Deward Hastings]

Kevin:

Is that blip in harmonic distortion at around 7kHz (Kepler) an artifact of the HDS tweeter, or is it a residual effect of cone breakup on the midrange?

Looks like a very nice driver, and a nice implementation in the Kepler as well, btw . . . makes me wish I wasn't all built out in speakers right now . . . :T

[Kevin Haskins]

Kevin:

Is that blip in harmonic distortion at around 7kHz (Kepler) an artifact of the HDS tweeter, or is it a residual effect of cone breakup on the midrange?

Looks like a very nice driver, and a nice implementation in the Kepler as well, btw . . . makes me wish I wasn't all built out in speakers right now . . . :T

We THINK that blip was from a rub on the VC of the tweeter. We couldn't get them to do a follow-up measurement on another unit to see. It was too high for a cabinet buzz and it is WAY out of the bandwidth of the woofer. I'm using a 4th order acoustical @ 1.5K on the woofer.

I had that speaker in another chamber in Seattle and we didn't see anything at lower levels to indicate there was a problem on that unit but it could have been a gremlin from shipping or it just didn't show-up until you really cranked on the tweeter.

[Deward Hastings]

it is WAY out of the bandwidth of the woofer. I'm using a 4th order acoustical @ 1.5K on the woofer.

I noted that with approval in the SoundStage review, since "low and steep" is the approach I favor for dealing with cone breakup. I doubt that anyone would hear it . Still, I'd like to see further exploration of what's going on with the midrange at that frequency, even with the driving signal > 50dB down.

I've got this "thing" about cone breakup . . . can't get too little of it . . .

[Kevin Haskins]

I noted that with approval in the SoundStage review, since "low and steep" is the approach I favor for dealing with cone breakup. I doubt that anyone would hear it . Still, I'd like to see further exploration of what's going on with the midrange at that frequency, even with the driving signal > 50dB down.

I've got this "thing" about cone breakup . . . can't get too little of it . . .

Most of it is a broad 10dB peak @ 4-5K, and there is a pesky peak @ 1.5K in the PE cabinet. My electrical filter is 10dB down @ 1.5K to achieve both the 4th order acoustic and to give it some baffle step.

It is a paper cone, but a light one that isn't super duper in the dampening department. Some of the break-up is surround related too because we are using that big 12mm roll surround so that we can use all that stroke.

I doubt that little burp at 8K is audible, simply because that measurement is at 101dB @ 1M and it's still less than 5% THD.

[cjd]

Mmmmmm. I've been hoping these would become available. Would love to use some in a dipole project that's been cooking for a couple years.

C

[Deward Hastings]

I doubt that little burp at 8K is audible, simply because that measurement is at 101dB @ 1M and it's still less than 5% THD.

At my age there aren't *any* audible harmonics of 8kHz . . . . . . but I still worry about breakup related non-linearities generating IM and "Spectral Contamination" when there's other signal on the cone. Since just about nobody is publishing multi-tone IM tests (especially with some of the tones sitting in the breakup region) I tend to notice anything that might serve as a proxy, or suggest odd behavior that might be folding back down into a more significant, and audible, frequency range.

I think your lower-than-most 4th order crosover addresses the issue as it should be addressed, and would expect the Kepler to sound clean because of it. The reviewer seemed to agree . . . . Letting the motor establish excursion limits rather than the suspension seems a good design choice as well, although not an easy one to accomplish with such a long throw motor. I hope the driver sees a lot of use out there, and does well for you . . .