original crossover schematics for clone ATC SCM 100

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The SCM50/ SCM100 used the old model Vifa Ferrofluid-cooled Soft dome 25mm (one inch) tweeter, which i presume made to order per ATC specification, unkown type/ model - probably similar to D25-TG-05-07. That was before 1997/8??.

The newer model, especially SCM50 SL PT / SCM100 SL PT 3-way passive monitor floor standing system uses Seas Excel either T25C-003 (E036) or T25FC-001 (E006) and for sure not a Millenium T25C-002 (E011).

See below information that I recently found ATC catalog/ brochure on Japaneese

http://www.electori.co.jp/atc/SCM50SLPT.pdf

http://www.electori.co.jp/atc/SCM100SLPT.pdf

I am pretty sure for this. See the picture of the tweeter.
 
Nice build! Couple questions for you. On the tweeter and mid ATC is using a sort of T pad layout for padding. Anyone know why they use this over something more conventional like an L pad layout?

Also is the top of the mid dome flush with the baffle or is it recessed pretty deep? What is the curvature of the roundover for the mid? Looks like maybe 1 1/4"? Also do you have any close up pics of the dome so I can see how the dome and roundover are in relation? Also do you have response measurements of this driver? Reason I ask all this is I'm using a new 3" mid from Tangband that I need rearmount in a waveguide similar to the ATC but I'm unsure of the dimensions. Here is a pic:

TB_3_dome.jpg


It's an underhung motor with shorting rings and a coated fabric dome. I'm sure they took more than a little "inspiration" from ATC. 3rd party measurements show a fairly flat response but with a dip centered around 2khz that goes away off axis. Non linear distortion is extremely low, particularly high order and IMD. I'm going to match this with the Seas T25CF001 and Peerless 830884, although an AE 10" like the TD10H or TD10X is tempting but out of my budget.

Thanks for any info you can give.
 
@tamariska
thank you for the information!

@augerpro
There is a "mini" WG Baffle delivered with the ATC. With this part you can put the driver on the back and the dome doesn't touch the gorund.
But you can remove it - carefully!!

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


I use the ATC in a selfmade Waveguide.
But I'm also interested in the Tangband 3" Dome, but I've never seen measurements before. So I'll be happy to see some, if you have.

best regards

P.S. i hope this was the question... my english is poor :smash:
 
Thanks for the pics. looks like the waveguide profile is about 1 1/4" or so. With the factory waveguide how much clearance do you think there is between the tip of the dome and the top of the waveguide/baffle face? In other words how deeply recessed is the dome?

Here are some measurements: http://www.audioheuristics.org/measurements/Testing/TB75/TB75.htm

The overall response contour is nearly the same as teh ATC, with the dip at 2khz being a bit deeper.