ATC SM75-150 versus SM75-150S

Tenson · 29th December 2010, 08:11 PM

I heard the SM75-150S isn't available anymore. So what is the difference between the S and the non-S version? Is it mainly sensitivity? I've seen Shin's measurements of the SM75-150S and the distortion levels are very impressive, and I wonder how the non-S version compares?

makingmoney · 09:48 PM

I have a pair of the sm75-150s 16 ohm for sale.
Cosmetically not perfect.
About 13-15 years old. Used mostly with a 300B amp. It put out a whopping 5 watts.
PM me if interested.

Tenson · 30th December 2010, 06:24 PM

Thanks, but if the only difference is the sensitivity, I think I might rather get a new pair of non-S versions, since 13+ years seems pretty old.

Really, has no-one ever found out the exact differences between these drivers?

Charles Darwin · 30th December 2010, 07:34 PM

You could just go to ATCs site and download the zip file (pdf).
But apart from sensitivity, total magnetic flux and flux density they appear identical.

TwangBar · 31st December 2010, 05:49 PM

From what I have read, the only difference is the sensitivity increase for the S version. The cone assembly is the same for both (the same recone kits work for both versions). If you look at pictures of the units, the S version has a much bigger/stronger magnet which provides the sensitivity increase.

Cheers

Tenson · 31st December 2010, 07:42 PM

One has to wonder then, why ATC use the S version even in their active speakers where sensitivity is not an issue, and also in their passive ones with low sensitivity.

I did email ATC to ask the difference, but I guess they are on holiday at the moment since they haven't replied for a couple of days.

Charles Darwin · 31st December 2010, 08:09 PM

It has to keep up with up to two 15" woofers while maintaining sufficient headroom for un-compressed signals. 3dB can count for a lot at times.

Tenson · 09:14 PM

I think you're confusing sensitivity with maximum SPL. Some of the speakers using the S version only have ~86dB sensitivity.

Charles Darwin · 1st January 2011, 10:06 PM

Both s and non-s only come in 16Ohm impedance so in a passive set up you only get 88dB for 2.83V from a non-s.
And in the larger actives it needs to keep up with twin woofers in terms of maxSPL.

Tenson · 1st January 2011, 11:02 PM

Oh yeah you're right. The spec sheet says sensitivity, but then they quote output for 1watt rather than voltage.

29th December 2010, 08:11 PM	#1
Tenson diyAudio Member Join Date: Feb 2006 Location: Kent	ATC SM75-150 versus SM75-150S I heard the SM75-150S isn't available anymore. So what is the difference between the S and the non-S version? Is it mainly sensitivity? I've seen Shin's measurements of the SM75-150S and the distortion levels are very impressive, and I wonder how the non-S version compares?

29th December 2010, 09:45 PM	#2
makingmoney diyAudio Member Join Date: Nov 2008	I have a pair of the sm75-150s 16 ohm for sale. Cosmetically not perfect. About 13-15 years old. Used mostly with a 300B amp. It put out a whopping 5 watts. PM me if interested. Last edited by makingmoney; 29th December 2010 at 09:48 PM.

31st December 2010, 09:09 PM	#8
Tenson diyAudio Member Join Date: Feb 2006 Location: Kent	I think you're confusing sensitivity with maximum SPL. Some of the speakers using the S version only have ~86dB sensitivity. Last edited by Tenson; 31st December 2010 at 09:14 PM.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
ATC SM75-150S+R2 or ESG1	Selfmade	Multi-Way	17	2nd May 2011 08:57 AM
For Sale: 2 x ATC SM75.150S	dkxdn	Swap Meet	8	17th July 2008 09:26 PM
xover for atc sm75-150s	montana	Multi-Way	2	8th July 2007 05:25 PM
ATC SM75-150s x-over design help?	T-Dot	Multi-Way	2	4th January 2007 08:02 AM
Fs: Atc Sm75-150s	triode4	Swap Meet	1	7th September 2006 01:55 AM


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

30th December 2010, 06:24 PM	#3
Tenson diyAudio Member Join Date: Feb 2006 Location: Kent	Thanks, but if the only difference is the sensitivity, I think I might rather get a new pair of non-S versions, since 13+ years seems pretty old. Really, has no-one ever found out the exact differences between these drivers?

30th December 2010, 07:34 PM	#4
Charles Darwin diyAudio Member Join Date: Nov 2009 Location: Birmingham, UK	You could just go to ATCs site and download the zip file (pdf). But apart from sensitivity, total magnetic flux and flux density they appear identical.

31st December 2010, 05:49 PM	#5
TwangBar diyAudio Member Join Date: Jan 2003 Location: Ottawa, Canada	From what I have read, the only difference is the sensitivity increase for the S version. The cone assembly is the same for both (the same recone kits work for both versions). If you look at pictures of the units, the S version has a much bigger/stronger magnet which provides the sensitivity increase. Cheers

31st December 2010, 07:42 PM	#6
Tenson diyAudio Member Join Date: Feb 2006 Location: Kent	One has to wonder then, why ATC use the S version even in their active speakers where sensitivity is not an issue, and also in their passive ones with low sensitivity. I did email ATC to ask the difference, but I guess they are on holiday at the moment since they haven't replied for a couple of days.

31st December 2010, 08:09 PM	#7
Charles Darwin diyAudio Member Join Date: Nov 2009 Location: Birmingham, UK	It has to keep up with up to two 15" woofers while maintaining sufficient headroom for un-compressed signals. 3dB can count for a lot at times.

1st January 2011, 10:06 PM	#9
Charles Darwin diyAudio Member Join Date: Nov 2009 Location: Birmingham, UK	Both s and non-s only come in 16Ohm impedance so in a passive set up you only get 88dB for 2.83V from a non-s. And in the larger actives it needs to keep up with twin woofers in terms of maxSPL.

1st January 2011, 11:02 PM	#10
Tenson diyAudio Member Join Date: Feb 2006 Location: Kent	Oh yeah you're right. The spec sheet says sensitivity, but then they quote output for 1watt rather than voltage.

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read