Alpair 10 Gen. MAOP Prototype TW-1

[markaudio]

Hello Chaps,
Here's some pics of the new MAOP prototype Alpair 10, essentially a Gen. 2 driver with 2 major tweaks:

1 - You'll note the cone. This is a standard Alp10 Multiform cone that has been treated with a new variant of the MAOP coating process. Comprising of a bonding layer onto the cone alloy substrate, and 2 other semi porous layers of material to make the finish you see on the pics. I'll release more details on this process once I've completed the results analysis from last weekend's tests.

2 - Matsubara san has been busy with yet another modified version of the Alpair 10 low mass spider. I think there's some pics on other threads of this component. I'll post another just in case.

More info coming soon.

Cheers
Mark.

[vinylkid58]

Cool.

[simon dart]

Hi Mark,
Can you explain the MAOP process and expected benefits in a little more detail. I've searched but can't find anything illuminating. Or is that for next week? :-D

Cheers, Simon

[markaudio]

Originally Posted by simon dart

Hi Mark,
Can you explain the MAOP process and expected benefits in a little more detail. I've searched but can't find anything illuminating. Or is that for next week? :-D
Cheers, Simon

Hi Simon,
MAOP, short for Micro Arc Oxidation Process.

Its a coating process thats been around for a while although new compared to other more traditional methods such as Anodising, powder etc.

While MAOP has some similarities to traditional applied oxide based processes, a higher potential is passed via the alloy substrate (the cone bass material) to effectively grow a crystaline oxide over the substrate. This process is ideal for adding weather protection, reduced wear on contact surfaces and also provides for electrical isolation.

There is a reference to this process in Wiki. While its not comprehensive, it may help to illustrate the basics of the process:

Plasma electrolytic oxidation - Wikipedia, the free encyclopedia

We've got access to a company that has moved this process on. They can provide a particular type of Multi-layered MAOP that allows close control of process, to a degree similar to that we current apply be conventional anodising.

The advantage we get with MAOP is closer control of the coatings on the substrate. The other advantage is the ultra low addition of mass, only around 0.3% increase on a standard Alpair 10 unfinished cone, that compares well to anodising.

See the attached pic. This is an illustration of the process at this prototype stage as per Alpair 10 Gen.2 TW. We may yet further develop the layers but at this point, the process is pretty ready to launch a variant of the Alp 10 as a "special".

Cheers

Mark.

[simon dart]

Thanks Mark. Interesting process. That just leaves why are you playing with it, what effect does it have on the sonic properties of the driver?

[markaudio]

Originally Posted by simon dart

Thanks Mark. Interesting process. That just leaves why are you playing with it, what effect does it have on the sonic properties of the driver?

Hi Simon,
Thats the interesting question. Theoretically, the porous layers should help disperse the micro-resonance more evenly as they pass over the cone's surface. I have my own measuring equipment that detects these micro characteristics but I'll need more time to calibrate for the different refractive capacity of MAOP. While I can measure the micro-resonant difference in the coatings, this won't really tell us of the potential audible change in the sound. For that, I'm going to pass the drivers to listening groups and ask them to feed back.

I'm about to post the LMS results.

Cheers

Mark.

[markaudio]

Hi Guys,
Here's the MAOP - TW data:

Technically, I like the look of the frequency. It looks well controlled across the range. There are a couple of moderate peaks at the 8 to 10-kHz region but nothing wild. The new Mastubara san spider is looking good. The parameters are close enough to the standard model to make retrofitting into most existing box plans easy.

Revc= 7.200 Ohm
Fo= 36.905 Hz
Sd= 8.992K mm²
Vas= 26.949 Ltr
Cms= 2.347K uM/N
Mmd= 7.434 g
Mms= 7.924 g
BL= 5.345 T·M
Qms= 2.740
Qes= 0.463
Qts= 0.396
Levc= 88.933u H
No= 0.283 %
SPL= 86.534 dB
X max= 8.5-mm (1 way)
Power = 35 watts nom. 70
Max Coil = 25-mm alu body with rectangle copper winding.

Thanks
Mark.

[silverhairbp]

Interesting results. It appears that one of the drawbacks might be that the measurements seem to indicate a bit less high frequency extension (though the response is a bit smoother). Not being critical, it looks highly listenable, veru smooth, nothing stands out as possibly annoying or detractive. Very nice.

Was the driver sufficiently / completely broken in for the measurements?

[chrisb]

is it possible to apply this process in a masked or CNC controlled pattern?

[kristleifur]

It's gorgeous.