Another special edition ScanSpeak driver...a $22 variant of the 10F

Face

https://www.madisoundspeakerstore.com/approx-4-fullrange/scanspeak-10f/8422-03-4-full-range-special/

Response is a little wonky, but nothing terrible.  I like the low inductance and frame design, the driver doesn't need to be recessed.

Mzisserson

I may need to grab a pair. BSC and the step signature can take care of a lot of that reaponse. Would make a nice, low-distortion mid for an inexpensive build. 

PWRRYD

Nice low Mms too, but sensitivity is pretty low.

Mzisserson

PWRRYD said:

Nice low Mms too, but sensitivity is pretty low.

Not in an MTM it aint! funny, too when do you ever see a 4" with a x-lim of +/-7mm? 8.7mm winding height and 4mm gap. bet they stay pretty for some time, too. 

Strange little driver, but I am seeing some potential there. 

ani_101

how does this compare to the 10f midrange at 1/5th the cost?

PWRRYD

I will probably order a pair on Monday  

PWRRYD

Boo! Madisound is closed today.  Hopefully open tomorrow.  

I agree Mike.  Centered on a 9" wide baffle the FR smooths out nicely.

PWRRYD

My pair just showed up.  I always forget just how small a "4 inch" driver really is.  They hopefully will work very well with the other twenty($)something drivers I'm using in this project.

Since it is a surface mounted driver, and I'm using a 1.25" thick baffle, it will take some serious rear baffle clearancing!

Mzisserson

Any initial impressions? I have two pair (thinking mtm) in the cart but haven't built the chops to press checkout yet. 

PWRRYD

Mike, the weather here was so great today (43 F and mostly sunny) that I spent most the day outside with the table saw and router making dust.  But I did visually inspect them.  In a nut shell, these look so much like a Vifa TC9FD18.  The paper cones, dust caps, and rubber surrounds look exactly the same.  The magnets look identical too.  Besides one frame being round and meant for surface mounting and the other having the rounded off corner square frame, the polymer (molded plastic) frames look like the work from the same Engineer, or company.  I do like the Vifa TC9FC but I'm hoping for better performance from this SS driver.  Again this is purely visual impressions thus far....

Mzisserson

PWRRYD said:

Mike, the weather here was so great today (43 F and mostly sunny) that I spent most the day outside with the table saw and router making dust.  But I did visually inspect them.  In a nut shell, these look so much like a Vifa TC9FD18.  The paper cones, dust caps, and rubber surrounds look exactly the same.  The magnets look identical too.  Besides one frame being round and meant for surface mounting and the other having the rounded off corner square frame, the polymer (molded plastic) frames look like the work from the same Engineer, or company.  I do like the Vifa TC9FC but I'm hoping for better performance from this SS driver.  Again this is purely visual impressions thus far....

Thanks!

jr@mac

PWRRYD said:

Mike, the weather here was so great today (43 F and mostly sunny) that I spent most the day outside with the table saw and router making dust.  But I did visually inspect them.  In a nut shell, these look so much like a Vifa TC9FD18.  The paper cones, dust caps, and rubber surrounds look exactly the same.  The magnets look identical too.  Besides one frame being round and meant for surface mounting and the other having the rounded off corner square frame, the polymer (molded plastic) frames look like the work from the same Engineer, or company.  I do like the Vifa TC9FC but I'm hoping for better performance from this SS driver.  Again this is purely visual impressions thus far....

The advertised response curves are strikingly similar, and for that matter the impedance curves are not all that different, either. The Scan advertises a lower Q and a somewhat lower Xmax but Scan has been known for being wrong on those things.

I just bought a pair of NOS Realistic ribbons and a pair of NOS Realistic cone midranges (those will be a crapshoot - ferrofluid in the voice coil might be toast after 30 years), so I will not be indulging any more of these fine drivers from Madisound right now, as compelling as they are. 

PWRRYD

Not that I have tons of free time, but it would be interesting if I whipped up a insert panel to test these two drivers on my IB rig.  I could see where they used the same catalog cones, dust cap, and surround.  I would think a different spider would lower the Q.  Hopefully there are improvements in the motor design (maybe a shorting ring) that lowers distortion, not that the TC9FD is bad.

ani_101

Ok, so I got a quad of these. Received them today and did a quick measurement, on carpet, mic about a meter over the driver.


No box, came in this foam cutout wrapped in cling film.

Tiny little drivers.

ani_101

Now on to the measurements. This is the DATS summary for all 4 of them.




Not too far off from each other. This is taken without break-in.

ani_101

FR measurements in Holm Impuls. Nice rakcing between the units.

The first graph shows Driver A, C and D. The second one shows Drivers B, C and D.

ani_101

Now for the Distortion Measurements in ARTA. I set the SPL pretty loud, but not sure what it was exactly.... it is definitely not 90DB (lower for sure).

First 4 (Driver A,B,C,D) graphs gives the relative SPL distortion, the next set is in Percentage.









_______________________________________________________
The next set of graphs show the distortion percentages (%)
Graphs are in order of Derive A, B, C,

ani_101

Oh, and these have much better 2.83V SPL than published. 

I measure all 4 of them in the 87+db for the 2.83V which is better than the 84db published. This puts them in typical mid-woofer sensitivity. in an MTM these would be real nice... but would need to double up on the woofers to keep up!

So, what would be a good application and applicable pass band for these? 

Craig, if you can please post the infinite baffle FR, those would be more accurate.

Regards
Ani

jr@mac

The Qts puts them pretty much spot on with the Vifa TC9. 

Mzisserson

Ani,
   Thank you for all of your hard work! 

PWRRYD

As luck has it my RS28 insert flipped backwards is the perfect size for both this new special Scanspeak driver and the TC9FD driver.  And the ND25FW driver fits perfectly in the RS28 rebate.  So when I get some time I will measure all three on my 4x4 test baffle.

kennyk

Since this is "show-n-tell", I got a quad today. Measured at 1.25in and ice cold.


#1 and #2 DATS PDF. And #3 and #4 DATS PDF. (at the bottom)
 

#1 FR and dist.

#2,

#3,

And #4.

PWRRYD

What was the set up Kenny?  On a baffle?

kennyk

No, I didn't use a wine bottle...........think I should?

R-Carpenter

2k will need a notch unless it's used in array.

ani_101

what sort of array? and what would be crossover points for the array?

kennyk

The 2k bumpski could be an environmental noise. I have a wine frig in the same room and furnace in the next room. Will have to repeat the measurements in better conditions. 

R-Carpenter

2K bumpski is present on all sweeps and accompanied by dist increase. I doubt it;s the wine fridge.Fridge would add noise below 500hz, visible on CSD if the signal to noise ratio is low.
BTW Kenny, my beer aging fridge is now dedicated to beef aging. 

ani, I would do a 3-way array. You could go passive or active. Single tweeter for smalish (6 mids) array or may be a group of 3 or more tweeters for a full size array. Crossover points would be more or less like on a conventional loudspeaker. 2k between tweeter and midwoofers. I'd probably push to 300hz between midwoofers and woofers,

jr@mac

To be perfectly honest, that 2K hump looks a lot more like an artifact of the baffleless testing. Here is a rough approximation of the effect derived from Jeff's RM software:

PWRRYD

That's what I thought too.  When I finish making dust I'll drag out and set up my IB and grab some FR and distortion curves.

R-Carpenter

Could be, I haven't tested baffless in years. It'll be interesting to see.