Some random driver tests

[Reet]

Biggest problem with Omnimic is the noise floor is quite poor, with just a basic USB audio codec. OM1 mic has low self noise, and can be connected to low noise ADC. Here's some basic comparison I made some years back when I got it, and used Steinberg UR22mkii at the time, I am using Motu M4 now which is even better.

https://diy.midwestaudio.club/discussion/1825/distortion-comparison-dayton-omnimic-vs-line-audio-om1-ur22mkii#latest

I haven't bothered to do any more comparison than that. The OM1 mic has proven to be perfectly adequate. Omnimic only collects dust now, until I decide I need absolute SPL reading.

[Reet]

Coming soon, Satori MW16P. Probably nothing new to be learned from my testing, since it's already well tested by Hificompass. That will be it for my driver testing for some time.

Next up will be some waveguide experimentation with a few of the tweeters tested here. I will be milling waveguides in wood with a CNC machine, it may take a bit for me to dial in the settings, but should be able to provide some direct comparison to the stock flat faceplates, in the same cabinet and baffle location.

[theSven]

Coming soon, Satori MW16P. Probably nothing new to be learned from my testing, since it's already well tested by Hificompass. That will be it for my driver testing for some time.

Next up will be some waveguide experimentation with a few of the tweeters tested here. I will be milling waveguides in wood with a CNC machine, it may take a bit for me to dial in the settings, but should be able to provide some direct comparison to the stock flat faceplates, in the same cabinet and baffle location.

Looking forward to see some more waveguide testing. The CNC sounds like a fun time and different from the 3d printing that has been shared lately on the forum.

[Reet]

I have ideas to mill some nice shapes directly into a baffle, it can look pretty cool when done well. Image courtesy of Joseph Crowe.


I did a quick test run as a proof of concept a while back, just to show that I can do it. I made a model in FreeCAD in a way that I can very easily modify the throat, mouth, and curve profile to dial it in just right.



For those without CNC or 3D printers, DIY waveguides are not out of reach, there is always the plaster method:

https://www.diyaudio.com/community/threads/low-budget-and-easy-method-for-diy-waveguide.327197/

[technodanvan]

Does one try to smooth that out via sanding or fill it with Bondo (or similar) to get a smooth finish?

[Reet]

5 min of sanding and it's smooth. That is just a "quick test run proof of concept" as I said, router bit with 40% step over. For final cut I would do more like 10% step over, it'll take a lot longer to machine, but require very little cleanup when complete.

[technodanvan]

Interesting stuff, worth looking into in the future.

[Steve Manning]

Does one try to smooth that out via sanding or fill it with Bondo (or similar) to get a smooth finish?

Here you go Danny in terms of needing sanding ....

This is a waveguide test I did for Jon some time ago. It's a two sided machine .... backside for mounting hardware and then flip for the actual waveguide.





This is the roughing pass to remove the bulk of the material.



This is the finish pass, no sanding at this point.



Part cut out, still no sanding.

[Reet]

SB Satori MW16P-8.


Apart from a blip at 1.5kHz that is likely from the surround, the frequency response is very good. There is no damping goo on front or back side of this driver at the cone-surround edge, which I think could alleviate this problem. Unfortunate miss on this calibre of driver.


IB estimation.


Distortion tested at 2.8V. Again, other than 1.5kHz blip, it's top tier.


Again at +5dB (~5V).

[tktran]

That higher order distortion really is outstanding!
That motor is fantastic; and I like the low weight of the driver too.

I wish SB would put an alu cone on the Satori motor. But I wonder if that would cannibalize sales from the Textreme Satori.

[duvixan]

I wish SB would put an alu cone on the Satori motor.

Marten's Parker series uses OEM ceramic 7.5" Satoris with a grill, to make them look Accuton-y

[Reet]

A couple more are coming soon. Vifa/Tymphany/Peerless NE180W-08 will be added, as well as Peerless/Tymphany HDS Exclusive 830883.

[Reet]

Vifa/Peerless/Tymphany NE180W-08. Great looking and performing midwoofer. Similar type of cone to Satori, I like the look of the yellow reeds in the NE180 better. Motor looks somewhat unimpressive as a small lightweight thimble, but performance is high, and light weight is important for some applications. Potentially, the rear wave may be fairly unobstructed for a dipole.


Frequency response is very smooth, with mild breakup.


IB Estimation.


Distortion at 2.8V.


Again at +5dB (~5V).


With a filter applied with 2.5kHz LR4 target.

[Reet]

Peerless 830883 HDS Exclusive. These are Tymphany branded, not the old DST drivers. Also a very nice driver, maybe a bit better performer than NE180W.

Frequency response.


IB estimation.


Distortion at 2.8V.


Again at +5dB (~5V).


With a filter applied for 2.5kHz LR4 target.

[Reet]

Directivity comparison. Here is power & di chart of normalized response for NE180W and 830883, very similarly sized drivers, but with different cone profiles, and of course one has a "phase plug". Dashed lines is NE180W, solid 830883.

[tktran]

Thanks Reet

My analysis is that the Satori has the best motor. The higher order distortion products are about ~6-10dB better than the rest. No wonder a certain doctor from KEF thought I was referring to the Satori when I was giving feedback about his coaxial.
The 2nd order is a bit higher than the rest, probably due to the cone. 5th element has been championing for a metal cone Satori for a long time, and I concur.

The 830883 is a little better than the NE180W. Below 250Hz it's better, and it has a slightly smoother response.
How does the silver frame look like in person?
There's still plenty of stock down under (since we're the last to get things, we seem to be the last to run out of things)

Perhaps it will go well with modern finishes like white cabinets...

[Reet]

If the Peerless HDS is goes with your modern decor, then it must have been ahead of it's time

I like it's unique character, you definitely won't mistake it for anything else. Finish is not silver, but rather light grey, almost an industrial powder coat in appearance.

[duvixan]

Both still available on aliexpress

https://aliexpress.ru/item/1005002416110478.html?sku_id=12000027342202733&spm=a2g2w.stores.seller_list.0.41e34cf3kU7ov2

https://aliexpress.ru/item/32889657185.html?sku_id=12000033665130984&spm=a2g2w.stores.seller_list.0.41e34cf3kU7ov2