• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

ATC speakers / Monitors

Scholl

Member
Joined
Jul 4, 2020
Messages
52
Likes
133
Except for some models like the SCM19 or SCM20, most ATC speakers are ported, not sealed.

I am not an expert in that field, but ported speakers can be designed in a lot of ways, with woofer TS parameters, enclosure internal volume, port shape, cross section and length all being interconnected.

AFAIK, ATC ported speakers tend to have quite high internal volumes, and short ports. By increasing enclosure volume and/or increasing vent length, one can lower the port tuning frequency. Longer vents, depending on the application, have some drawbacks. Ports will generate harmonic resonances based on their length. The longer the vent, the lower the resonance frequency. In a subwoofer application, this may not be an issue since they do not reproduce audio much higher than 100hz. But ATC 3 way speakers have their lower crossover at 380hz. Too long of a vent may produce audible resonances below that frequency. The issue is of course even worse with ported 2 way speakers, since their crossover is much higher.

Ported enclosure design also affect the FR shape. Some box design can result in a peaking resonance at the port tuning frequency. More port output, at the cost of a "one note sub" type of sound, especially with room gain. Because of their design choices, ATC tend to have low port output, which result in leaner bass, which looks more like typical sealed box FR. This design choice is, in my opinion, probably one of the reasons why ATC speakers have long been popular with recording engineers. Just like the famous NS10, for some engineers it is better to have lean, but clean and non resonant bass, than lower extension at the cost of linearity, especially in the time domain.

Modern speaker design with equalized sealed enclosure equipped with large, high excursion woofers in combination with lots of class D power tend to nullify those ported speaker issues. But those design have only recently been possible, and are still rare, expensive and sometime plagued by questionable design choices (some Barefoot midwoofer/tweeter section IMHO).
 
Last edited:

dfuller

Major Contributor
Joined
Apr 26, 2020
Messages
3,338
Likes
5,053
Except for some models like the SCM19 or SCM20, most ATC speakers are ported, not sealed.

I am not an expert in that field, but ported speakers can be designed in a lot of ways, with woofer TS parameters, enclosure internal volume, port shape, cross section and length all being interconnected.

AFAIK, ATC ported speakers tend to have quite high internal volumes, and short ports. By increasing enclosure volume and/or increasing vent length, one can lower the port tuning frequency. Longer vents, depending on the application, have some drawbacks. Ports will generate harmonic resonances based on their length. The longer the vent, the lower the resonance frequency. In a subwoofer application, this may not be an issue since they do not reproduce audio much higher than 100hz. But ATC 3 way speakers have their lower crossover at 380hz. Too long of a vent may produce audible resonances below that frequency. The issue is of course even worse with ported 2 way speakers, since their crossover is much higher.

Ported enclosure design also affect the FR shape. Some box design can result in a peaking resonance at the port tuning frequency. More port output, at the cost of a "one note sub" type of sound, especially with room gain. Because of their design choices, ATC tend to have low port output, which result in leaner bass, which looks more like typical sealed box FR. This design choice is, in my opinion, probably one of the reasons why ATC speakers have long been popular with recording engineers. Just like the famous NS10, for some engineers it is better to have lean, but clean and non resonant bass, than lower extension at the cost of linearity, especially in the time domain.

Modern speaker design with equalized sealed enclosure equipped with large, high excursion woofers in combination with lots of class D power tend to nullify those ported speaker issues. But those design have only recently been possible, and are still rare, expensive and sometime plagued by questionable design choices (some Barefoot midwoofer/tweeter section IMHO).
My understanding on top of this is that ATC tends to tune for a Q of about 0.5 rather than 0.707 - they'd rather the better transient response vs the greater linear extension. That's a legitimate design choice.

What I can't fathom is their absolute refusal to waveguide load their tweeters. They already do on their midrange, so why not the tweeter?
 

TheBatsEar

Major Contributor
Forum Donor
Joined
Jun 16, 2020
Messages
3,084
Likes
4,962
Location
Germany
That is why ATC price range is ridiculous for me (EU), and does "not understand" their popularity/hype.
You sound like you are poor. :p
But yes, i would have updated from my SCM 19 v2 for sure if i had spare cash, i like them very much and would love to have larger ATCc some day.
I'm stalking Ebay for good prices ...
0c64b8f9043536e8ec6b840c842104e342515980af18553efb64ace69689994f.jpg
 

goat76

Major Contributor
Joined
Jul 21, 2021
Messages
1,269
Likes
1,385
You sound like you are poor. :p
But yes, i would have updated from my SCM 19 v2 for sure if i had spare cash, i like them very much and would love to have larger ATCc some day.
I'm stalking Ebay for good prices ...
View attachment 221128
I bought my SCM40 v2 for about 3700€/3800$ as a nice demo ex from a store. Well worth the price, maybe you can find something similar in Germany?

But yeah, ATC speakers are expensive but can we really blame them. If they sell everything they can squeeze out of their small factory, then it's also a clear indication they sell them for the real market value.

I understand why some people think ATC is overpriced, but at the same time, ATC have built up a “brand value” for making good quality speakers. I can't see anything wrong with that, it's up to every single person if they think the speakers are worth the price or not. Most of us accept the premium price for a BMW or a Mercedes Benz, even if we all know we pay a hefty sum of money for the emblem. :)
 

DSJR

Major Contributor
Joined
Jan 27, 2020
Messages
3,314
Likes
4,427
Location
Suffolk Coastal, UK
I'm in bits really. Not just for the loss of someone who really did make a difference to speaker design back in the day, but also brings back to me all the wonderful memories of factory visits, highly educative chats over lunches, Billy's infectious enthusiasm, ability to demonstrate what he talked about and his total lack of patronising sanctimonious vibes - and willingness to share his knowledge and enthusiasm that was infectious to a peep like me back then. I'm forwever grateful to him and his co-designer/director Tim Isaac for that.

Looking at the pics below brings it all back - This really was special back then, although obviously other pro speaker makers have come along and taken or shared the baton here

 
Last edited:

Torbachkristensen

Active Member
Joined
Mar 2, 2020
Messages
166
Likes
189
My theory (useless of course) is that ATC are good monitors and have a admirable history in the recording studio world. It would seem, however, that technology has passed them by and they are no longer the state of art. The good vibes remain for those who already have spent the large bucks for them and those who are influenced by those folks. Also, British users seem particularly fond of them (nationalism) and anyone that follows pop music realizes the outsized influence of British producers. And they ARE good - just not as good as other more recent offerings from Genelec, etc.

Measurements are the ONLY way to get to the bottom of it all.
Fun theory, but not true. Alot of these compact DSP speakers trying to circumvent the laws of physics come with too many compromises for actual Pro use, though marketing has surely made it's way in. ATC's might perform worse in casual listeners untreated livingrooms, but in a pro studio and acoustic environment nothing beats it for phase response, impulse response and balanced clarity.

The biggest mastering house in the world, Sterling Sound, based in Nashville and NY just installed ATC110 in 6 rooms designed by Thomas Jouanjean of Northward Acoustics, in 2018. I encourage you to look up interviews and info from him, he is probably the best and most innovative acoustic designer on the planet atm. And it is not a coincidence he only recommends ATC installs - if you don't like what you hear from them, it is the room, not the speaker.

That is not to say that DSP and Cardioid speakers like the Dutch 8c does not have it's place. But it is not better technology, it is just made with a different goal. Genelec and Neumann are also great speakers, but toss them in a real room and it is my experience that they don't perform quite as well as the "estimated in room response" here on ASR would suggest. Barefoot speakers are a fine example of everything that can go wrong with modern DSP designs + marketing. Insanely expensive speakers, that basically sound like a bunch of drivers tossed together, absolutely horrific.
 
Last edited:

Flak

Senior Member
Industry Insider
Joined
Nov 18, 2018
Messages
385
Likes
593
As I've understood it, from around 500Hz and up it’s the direct sound that is the dominating sound we hear. That's the reason why we should never do any EQ adjustment over that point based on the measurements taken from the listening position (as long as the measurements are not gated that is).
"The direct sound’s contribution to the frequency response as measured at the listening position is far less than that of the early and late reflected sound"
From here: http://www.acousticfrontiers.com/20...nse-psychoacoustic-and-subjective-importance/
 

Ilkless

Major Contributor
Forum Donor
Joined
Jan 26, 2019
Messages
1,757
Likes
3,437
Location
Singapore
Fun theory, but not true. Alot of these compact DSP speakers trying to circumvent the laws of physics come with too many compromises for actual Pro use, though marketing has surely made it's way in. ATC's might perform worse in casual listeners untreated livingrooms, but in a pro studio and acoustic environment nothing beats it for phase response, impulse response and balanced clarity.

The biggest mastering house in the world, Sterling Sound, based in Nashville and NY just installed ATC110 in 6 rooms designed by Thomas Jouanjean of Northward Acoustics, in 2018. I encourage you to look up interviews and info from him, he is probably the best and most innovative acoustic designer on the planet atm. And it is not a coincidence he only recommends ATC installs - if you don't like what you hear from them, it is the room, not the speaker.

That is not to say that DSP and Cardioid speakers like the Dutch 8c does not have it's place. But it is not better technology, it is just made with a different goal. Genelec and Neumann are also great speakers, but toss them in a real room and it is my experience that they don't perform quite as well as the "estimated in room response" here on ASR would suggest. Barefoot speakers are a fine example of everything that can go wrong with modern DSP designs + marketing. Insanely expensive speakers, that basically sound like a bunch of drivers tossed together, absolutely horrific.


More unsubstantiated, emotive appeals to authority stubbornly ignoring the psychoacoustic evidence. The usual ATC cult of personality and apologetics in practice. A superficially engineering-led cult of personality that on closer examination is based on outdated evidence and engineering is still merely a cult of personality.

It's peculiar how ATCs are cast as doing no wrong and that it's antiquated design (namely, lack of directivity matching and diffraction control) is a sign of reliable timelessness rather than denial on the brand and its adherents' part that technology has left them behind and their knowledge needs to be updated with the times.
 

Inner Space

Major Contributor
Forum Donor
Joined
May 18, 2020
Messages
1,285
Likes
2,938
It's peculiar how ATCs are cast as doing no wrong and that it's antiquated design (namely, lack of directivity matching and diffraction control) is a sign of reliable timelessness rather than denial on the brand and its adherents' part that technology has left them behind and their knowledge needs to be updated with the times.
This is incoherent, even by your standards on this issue. You were replying to a point about ATC mains soffit-mounted in a Northward non-environment room, which renders directivity and diffraction irrelevant. Were you to hear such an installation, I pretty much guarantee you would find it vastly, overwhelmingly, dramatically superior to anything else you have ever heard in your life. Why not gather some "psychoacoustic evidence" before sounding off?
 

thewas

Master Contributor
Forum Donor
Joined
Jan 15, 2020
Messages
6,747
Likes
16,182
"The direct sound’s contribution to the frequency response as measured at the listening position is far less than that of the early and late reflected sound"
From here: http://www.acousticfrontiers.com/20...nse-psychoacoustic-and-subjective-importance/
That is for the measured steady state frequency response at the listening position, it doesn't mean though that our perception is the same where as correctly written by @goat76 the direct sound dominates above transition frequency, let me quote Toole:

"The small dip should not be equalized because it alters the perceptually dominant direct sound."

"Sorry, but a small omni mic and an analyzer are not the equivalent of two ears and a brain. It is not uncommon to be forced to override auto EQ with manual adjustments to restore the inherent sound quality of excellent loudspeakers. In some cases the "off" icon is the preferred solution. The simple fact is that a steady-state room curve is not accurately descriptive of sound quality - comprehensive anechoic data are remarkably capable, but such data are rare."

Source: https://www.audiosciencereview.com/...ut-room-curve-targets-room-eq-and-more.10950/

That can be also understood as with typical loudspeakers with higher listening distances the tilt of the FR measured at the LP becomes larger because the reflected sound and sound power dominates more, but we don't really perceive them as dark(er) as the steady state measurement shows.
 

thewas

Master Contributor
Forum Donor
Joined
Jan 15, 2020
Messages
6,747
Likes
16,182
By the way that the direct sound dominates our perception doesn't mean that the directivity isn't as important, as like Toole writes, the reflected sound should be similar to the direct sound, which is also the reason why DRC/EQ do not really work well with poor loudspeakers and cannot really transform them to something better.
 

Ilkless

Major Contributor
Forum Donor
Joined
Jan 26, 2019
Messages
1,757
Likes
3,437
Location
Singapore
This is incoherent, even by your standards on this issue. You were replying to a point about ATC mains soffit-mounted in a Northward non-environment room, which renders directivity and diffraction irrelevant. Were you to hear such an installation, I pretty much guarantee you would find it vastly, overwhelmingly, dramatically superior to anything else you have ever heard in your life. Why not gather some "psychoacoustic evidence" before sounding off?

If said room is not anechoic, the following per Toole applies:

If the spectra of the direct and reflected sounds are significantly different, the reflections are likely to be more noticeable, from subtle timbral effects up to a premature breakdown of the precedence effect, at which point listeners may be aware of two simultaneous sound images, one located at the loudspeaker and one located at the point of reflection. This is obviously not good. Over the years this is likely a factor in listeners rating loudspeakers with uniform directivity more highly than those with uneven directivity. Wide dispersion seems to be good, but especially if it is uniform with frequency and the spectra of the reflections is not substantially altered. Hundreds of loudspeakers auditioned by hundreds of listeners in double-blind evaluations have demonstrated this; it is monotonously predictable.

Further to this, why is a great room an excuse for a deliberately crippled speaker? Why not both? Is it because it is difficult to admit that the world has left ATC behind and clinging on to the mystique as a status symbol all its adherents can do now?

What's worse than outright voodoo is the superficial commitment to evidence-based, empirical engineering like Chord, Harbeth and ATC despite the actual products being so far behind.
 

Phorize

Major Contributor
Forum Donor
Joined
Apr 26, 2019
Messages
1,533
Likes
2,060
Location
U.K
If said room is not anechoic, the following per Toole applies:



Further to this, why is a great room an excuse for a deliberately crippled speaker? Why not both? Is it because it is difficult to admit that the world has left ATC behind and clinging on to the mystique as a status symbol all its adherents can do now?

What's worse than outright voodoo is the superficial commitment to evidence-based, empirical engineering like Chord, Harbeth and ATC despite the actual products being so far behind.
You have right on your side in terms of whose speakers are better designed in relation to the current research but maybe you’re over egging the pudding. I’m not sure I’d lump these 3 companies in together, which to my mind look like this:

Harbeth-well intended and competent optimisation of a once valid but now antiquated design ethos, openly moving towards a more modern approach in recognition of the fact the the bbc era has passed.

Chord-generally competent company with access to engineering talent, ridiculous claims on what is audible made indirectly by contracted designers, but never by the company, idiosyncratic (and suboptimal) interfaces that reek of ‘not invented here’ syndrome, mostly objectively high performing products but some mediocre ones, prices targeting luxury market, not main stream.

ATC-just as Harbeth, but lacking a clear plan for moving with the times (as is common when a company has been under the stewardship of a founder for so long), so trading on prior reputation (not a silly strategy given the environment and its responsibilities towards shareholders and 61 employees) which is still high in some sections of the recording industry-much of which will lean heavily towards the genelecs of this world, but like any market, will vary and judge technology emotionally as well as objectively.

Pure punditry on my part obviously.
 

Inner Space

Major Contributor
Forum Donor
Joined
May 18, 2020
Messages
1,285
Likes
2,938
If said room is not anechoic
Why say this, when you know the room is anechoic? Rooms and speakers are parts of the same system and must be considered together. If the room offers no reflections and no baffle step, why even consider directivity and diffraction? Such an inquiry is redundant. How could either factor be remotely significant? You're arguing for the sake of it, from an amateur and inexperienced perspective, along an irrelevant path, for no discernible reason. Did your mom drop an SCM19 on your head when you were a baby? Again, make the effort to hear such an installation, and get back to us.
 

Digby

Major Contributor
Joined
Mar 12, 2021
Messages
1,632
Likes
1,555
Thank you for the link to the interview. I found this to be an interesting (my emphasis in bold):

Billy – coincidentally a gifted piano player – told me that his philosophy was entirely new. “We had to get away from this idea that you could have a loudspeaker of 25 watts and start off with an efficiency of 88dB at 1W at 1 metre and be able to replay piano; it was just impossible. You need power to reproduce that huge dynamic range, and piano's the worst probably – you're not listening loud. You need that huge dynamic range to reproduce that initial transient.
 

tw99

Senior Member
Joined
Mar 13, 2019
Messages
467
Likes
1,069
Location
West Berkshire, UK
I've probably said it before in this thread, but the ultra conservative approach is nice for product support. You can get the factory to service/upgrade 20-30 year old products. That is relatively rare nowadays, and a strong plus point for UK customers at least.
 

DSJR

Major Contributor
Joined
Jan 27, 2020
Messages
3,314
Likes
4,427
Location
Suffolk Coastal, UK
Thank you for the link to the interview. I found this to be an interesting (my emphasis in bold):

Billy – coincidentally a gifted piano player – told me that his philosophy was entirely new. “We had to get away from this idea that you could have a loudspeaker of 25 watts and start off with an efficiency of 88dB at 1W at 1 metre and be able to replay piano; it was just impossible. You need power to reproduce that huge dynamic range, and piano's the worst probably – you're not listening loud. You need that huge dynamic range to reproduce that initial transient.
BAH Humbug! :D

At the time I knew him, Billy used SCM10's at home!!! Small bass driver, painfully inefficient, great sound BUT they had their very definite ceiling beyond which the poor thing bottomed out!

Got to say I once (and have often recounted so apologies) did a comparison of the 100A's as I had then, to the 200A's, which doubled the bass drivers and put the amps in a grey 'block' between them, the multi-core snake type speaker cables connected by Burndy connectors (as used for caravan power? and expensive Naim power supplies). If the 100A's made 10's, 20's and the passive versions of the three ways sound small and a bit 'weedy' in comparison, the 200A's were a step again, the dynamic range significantly more due I believe to the two bass drivers working less hard by 'sharing the load' and the also greater output of the active amp block. Many years back now, but I'll never forget it. To bring this back, one performance played was a piano with tenor voice and yes, the piano dynamics was far closer to sitting at an actual instrumant - and then the tenor suddenly sang out, practically pinning us to the wall behind the listening sofa.

I'm so envious of those able to afford and accommodate good BIG speakers of whatever make. The vibe is totally different and far more 'real' than any smaller active wonder-box with active dsp keeping the bass deep, let alone tall tower types with multiple bass drivers. The latter is the norm now and maybe going back to larger 'proper in @restorer-john terms' speakers makes the latter sound 'coloured' in some way, but I don't care really. I'll forgive the JBL 4367 anything because of this ;)
 
Top Bottom