The ultimate dome midrange: ATC sm75-150

[npdang]

These belong to KevinK. I love how they dwarf those hiquphons. One of the only dome midrange's that I know of with a spider, underhung motor, and dual copper rings. I'll let him speak for their performance :)

http://diymobileaudio.com/pics/kev1.jpg
http://diymobileaudio.com/pics/kev2.jpg
http://diymobileaudio.com/pics/kev3.jpg

[cam2Xrunner]

Dang that thing is huge!

[kappa546]

so this is the review forum... wheres the review?!

[STI<>GTO]

:o
~$ 500 each!
:o
:o

[STI<>GTO]

In case anybody was ready to pull the trigger ----> getumhere! (http://www.solen.ca/pdf/atcusd.pdf) ;)

If those showed up at my house I think my wife would be pulling a trigger...

[Weightless]

Let's see some measurements... :)

[Beau]

Do you have to put those in an escrow account?

[zapjay]

Waiting to hear what you guys think about them. I almost bought a pair of them several months ago. Measurements would be killer....

[kevin k.]

Sorry for lagging, guys... I had back surgery two weeks ago and am not at the computer very much right now. I'm glad to give what little, thus far, I have in the way of impressions/experiences with the ATC's...

First, my thanks to Nguyen... you're a class-act and a good friend. Also, Nguyen is the one to post these pics for me as I have no way of doing it myself.

I've had an interest in these drivers for a few years now, but the size has always put me off... they are, as the pictures show, QUITE large... diameter is 19 cm and each driver weighs in the neighborhood of 15 lbs.

For those unfamiliar with ATC, you may be quite impressed with where these speakers are utilized. Check out...

http://www.atc.gb.net/

And go to their client list...

As far as measurements go, I do not have anything other than a RTA and my own ears. If Mr. Dang has measurements of these drivers squirreled-away from past experience then I'm sure he'll provide them. But, these particular domes came straight to me from Canada.

Nguyen does, however, have my Accuton C2 12/6 tweeters and C89/T-6 mids for testing/measurement purposes...

I can tell you that they have an fs of about 317 Hz and a measured sensitivity of 91 db... the 150S (Super) version is rated at 94 db and that is, supposedly, the only difference, spec-wise, between the two models. ATC uses the domes in their own speakers from 380 Hz to 3.8 kHz and they quote a useable range out to 5 kHz. Both the 150 and 150S are rated at a max. of 300 W @ 8 Ohms... :o

My system is in a 2002 Honda Accord 4 door and consists of the following...

Alpine DVA-7996
Alpine PXA-H700
ZAPCO C2K-3.0 running Hiquphon OWI tweeters
ZAPCO C2K-6.0 running the ATC SM75-150 mid domes
ZAPCO C2K-6.0 running two pairs of Scan 18W Revelator midbasses
ZAPCO C2K-6.0 running two Focal Utopia 33WX subs

I did a very rudimentary installation of the domes due to lack of time before my surgery... they are simply placed on the floorboard/kickpanel area... I removed the custom kickpanels and the mids that were in the car and have the domes placed against the mid enclosure baffles... since the kickpanels are pulled, the tweeters are simply mounted right next to the mids... if I can take some pics, I'll get them to Nguyen... seeing the domes in the kickpanel area will give an even greater idea as to scale and size.

The domes are set to run from 380 Hz to 3.2 kHz and there is no eq-ing whatsoever... all mid frequencies are set to flat to see what the drivers are doing "out of the box"... gain levels are, at this point, set by ear and matched to the rest of the system. I will try FR variations of the mids in the near future... e.g., running them up to 4 kHz, 5 kHz, and 6 kHz... also, perhaps a little lower, down to 350 Hz or even 320 Hz...

My initial impressions of the domes are that they are VERY dynamic, detailed, and with, imo, VERY low colouration. Midrange colouration is anathema to me and I've struggled with mid enclosures (sealed and vented) in the car. Vocals, through the domes, just sound so clear to me and are without any sort of sonic "signature" due to an enclosure (at least, the different enclosures I've had in my cars)... no bloatiness, chestiness, resonance, etc.

Off-axis response seems to be quite good. I also hope to do a some work with the RTA soon to get a better idea of what the drivers are doing in my car. Along those lines, Solen offers a flat baffle for the ATC's that eliminates the 'horn'-type baffle... I picked up a pair to see what the one baffle does vs. the other... should be interesting. Check out...

http://www.solen.ca/

Like I said above, I am quite taken with these drivers, although I certainly wouldn't mind if they could run down to, say, 200 Hz... ;) But, taking into consideration the given that these probably shouldn't be run much lower than 350 Hz, I would have to say that these are among the best, if not the best, sounding, to my ears of course, mids I've had in my car... I really like the dynamics, the detail, and there seems to me to be a sort of palpability that I find very appealing. I guess for reference sake, I should say that the mids I have used and own(ed) in my car include... Accuton C89/T-6, A/D/S, AudioTechnology C-Quenze 15, Dynaudio MD140, Focal Utopia 13's, KEF Uni-Q, Rainbow, Scan Speak 12M and 15W Revelators, Seas Excel 15, and some others I can't recall...

Anyways, thanks for the opportunity... thank you to Nguyen for making this review possible and for this forum. My first written review... hope it proves helpful and informative. Anyone interested in these drivers and my subsequent experiments/experiences with them is welcome to contact me. :)

[newtitan]

oh my I can only dream of those lol

im rather shocked you dropped 500 dollars in your car kick panels , id be scared theyd be damaged or something

[Thoraudio]

My response to each picture, in order.

1. Holy $h!t

2. Holy $h!t

3. Holy $h!t

[300Z]

im rather shocked you dropped 500 dollars in your car kick panels
On each side... :o

[dual700]

$500 per side? PFFFFTTT
When Kevin K showed me the RTA he had that is almost as slim as a Palm V, but costed $4500, I almost blacked out. :o

[kevin k.]

$500 per side? PFFFFTTT
When Kevin K showed me the RTA he had that is almost as slim as a Palm V, but costed $4500, I almost blacked out. :o

Hey Eng,

That thing was amazing wasn't it?! It was a Bruel & Kjaer Type 2250 and actually goes for more like $9000... :o

Check out... http://www.bksv.com/3153.asp

Lust personified... wish I coulda kept it! :(

Gonna spend a little more time with the ATC's today... pull out the RTA, try some different LP x-over points, and see what else I can come up with...

I'm REALLY liking those domes, although they couldn't be much further removed from the 2" and 3" mids that are so prevalent lately... :blush:

[tf1216]

Hey Kevin, Tyler here. I talked to you a while back on the telephone. I remember you telling me about some tests you conducted to see how accurate the XO was on your Alpine processor. Ever do the same for the P9?

For example, when it says 2.5kHz, is there really a slope starting at 2.5kHz?

[kevin k.]

Hi Tyler... sure I remember you :) Sorry, but I've not worked with a P9 combo other than just playing around with a friend's set-up.

[dual700]

Hey Eng,

That thing was amazing wasn't it?! It was a Bruel & Kjaer Type 2250 and actually goes for more like $9000... :o

Check out... http://www.bksv.com/3153.asp

Lust personified... wish I coulda kept it! :(

Gonna spend a little more time with the ATC's today... pull out the RTA, try some different LP x-over points, and see what else I can come up with...

I'm REALLY liking those domes, although they couldn't be much further removed from the 2" and 3" mids that are so prevalent lately... :blush:

$9000!!!

going to Coma... :o :D

[werewolf]

Are grills available for the ATC domes?

:)

[kevin k.]

Are grills available for the ATC domes?

:)


Why, yes, Jeff they are...





got a couple Weber bbq's laying around?

;)

[kevin k.]

Btw, Jeff, I sent you these pics about a week ago... did you receive them?

:confused:
:)

[werewolf]

yes kevin, I did ... thank you!

[kevin k.]

Are grills available for the ATC domes?

:)

I initially thought you were kidding with me, Jeff... :p

Still not sure... :blush:

But, if not, then the straight answer is "not that I'm aware of"... I do have some fabrication ideas, though... ;)

Glad you got the pics...

[werewolf]

it's one of my pet peeves (sp?) in audio in general, but especially in car audio where passengers are too near the damn drivers.

Supply some damn grills with the speakers! :mad:

At least make them optional, many would be willing to pay a couple extra bucks to cover the cost (and the intensive R&D required for a friggin metal screen that fits). Plus, we can always leave them off for "critical listening", and put them back on when monsters are in the car.

OK, rant done :) I know the ATC isn't designed for the god-forsaken world of car audio :(

[kevin k.]

Yes, yes, yes... I think we ALL know how you feel about speaker grills, Jeff! :p

I agree with you, though, and 'tis a pain in the arse to either fabricate something completely new or modify an existing grill... :mad:

So, for the most part, I let my drivers run naked and free... just as God and Nature intended!

I just figured you were joking about grills for the ATC's, since those are some of the LAST drivers I'd expect to find them for... ;)

[ShinOBIWAN]

Nice mids Kev ;)

Have you tried the super version of the SM75-150?

I've tried both but found the super to be even cleaner sounding and definitely more dynamic.

Just for comparison here's the standard vs. super for those that thought the baby dome mid was big:

http://img.villagephotos.com/p/2005-7/1050288/atcs1.JPG

http://img.villagephotos.com/p/2005-7/1050288/atcs2.JPG

[Sephiroth619]

Jesus christ!!!!

15lbs?!?!?!?!? Each?!?!?!?

Blasphemy.

[kevin k.]

Hi ShinOBIWAN,

You're definitely a man after my own heart... :)

I've not had the chance to try the Supers, and, unfortunately, that opportunity may never come to pass... at least in my car anyway. My standard 150 domes are to be installed in the kickpanel area of my car and putting Supers in that limited space did not seem possible... :(

But, hey, they sure are great drivers! :D

Btw, thank you for posting the pics of the different ATC's... nice to look at... ;)

[Sephiroth619]

I'll pay you money if I can sit in your car and have a listen. I'm serious too.

[Rbsarve]

I would have to say that these are among the best, if not the best, sounding, to my ears of course, mids I've had in my car... I really like the dynamics, the detail, and there seems to me to be a sort of palpability that I find very appealing. I guess for reference sake, I should say that the mids I have used and own(ed) in my car include... Accuton C89/T-6, A/D/S, AudioTechnology C-Quenze 15, Dynaudio MD140, Focal Utopia 13's, KEF Uni-Q, Rainbow, Scan Speak 12M and 15W Revelators, Seas Excel 15, and some others I can't recall...

That is an impressive list of alternatives mr K, would love if you had the time to tell us more of which other of the mid´s you liked and some comments on their characteristics!

Personally I´m quite fond of the 12m´s and the Acuuton´s in the right setting of course.

[schreibers]

I'm really interested to see what affect the different faceplates have on those mids. Keep us posted with pics and opinions!

[kevin k.]

As per mvw2's request for more reviews, here's an old one for my ATC midranges... :)