ATC speakers / Monitors

[thewas]

What I meant was that the off-axis responses are measured by a microphone from different angles around the speaker, without trying to simulate any kind of average room response and a simulated attenuating of the signal strength that a listener at the on-axis of the speaker would perceive.

Aren't the things we see in the directivity plots just full-strength measurements from those off-axis positions around the speaker?

A room doesn't correct directivity problems so to evaluate a loudspeaker performance anechoic measurements are necessary. An average room response doesn't tell anything which is the reason why equalisation cannot correct a loudspeaker with poor directivity. I can only recommend you reading Toole's comments on this thread:

Some comments from Floyd Toole about room curve targets, room EQ and more

Room curve targets Every so often it is good to review what we know about room curves, targets, etc. Almost 50 years of double-blind listening tests have shown persuasively that listeners like loudspeakers with flat, smooth, anechoic on-axis and listening-window frequency responses. Those with...

www.audiosciencereview.com

 

[goat76]

I've read many times that ATCs lack bass

According to the information I found they never use the ports in their speakers to extend the bass response, instead, it's a design choice where they use the port to reduce distortion which is something they seem to see as more important than bass extension (which can be had by adding a subwoofer instead). That's their design philosophy while other manufacturers have theirs, not everyone has chosen the same path.

"The reason that this ported speaker sounds like a sealed cabinet is down to ATC’s unique design. All ported cabinets have a resonant frequency, which is related to relative dimensions of the port and cabinet. Most designers use this resonance to artificially enhance bass response, particularly in smaller enclosures, which is why they often sound boomy and slow. By contrast, ATC doesn’t use the port to extend the bass, merely to reduce distortion by controlling the motion of the bass driver. ATC designs for a relatively low damping factor (Q) of around 0.5, which produces a gradual low-frequency rolloff similar to a sealed cabinet. By contrast, most ports are tuned to a Q of 0.7 or more, which reduces port damping and gives the impression of a more powerful bottom end—but often gives a “one note” bass response. A high-Q ported cabinet also has a much steeper rolloff than a sealed-cabinet design."

ATC SCM50 Passive/Active Loudspeaker

 

[goat76]

A room doesn't correct directivity problems so to evaluate a loudspeaker performance anechoic measurements are necessary. An average room response doesn't tell anything which is the reason why equalisation cannot correct a loudspeaker with poor directivity.

I never said that a room will correct directivity problems per se. What I mean is that if the early reflections are reduced in strength versus the direct sound reaching the listener at the listening position (which can either be achieved by absorption or distance), it will be less of a problem and even a none problem depending on how much the reflections are attenuated.

And before you come with the information again that early side wall reflections would be a good thing, I want to inform you I'm not one of those who share that view.

The early side wall reflections are down at -19 dB in my room, and that is even without using any absorption panels at the first reflection points, it's just the result of having a fairly small listening triangle and some distance to the side walls.

 

[YSDR]

The port tuning frequency of an ATC speaker is usually low and the speaker boxes are relative small but not too small (considering the T/S parameters of the woofers), the result is a gentle rolloff towards lower frequencies and not a sharp knee below the port tuning, like many modern monitors have.

 

[boxerfan88]

I've read many times that ATCs lack bass

It is true. I heard the 50 and it certainly missing a bit of the LF "body". I also heard the 100 and the LF "body" is better than the 50.
To my ears the KH310 (sealed cabinet) provides more LF "body" to music compared to 50 (within the limits of what the KH310 8" can do).
I suppose that is the way ATC wants to tune them... no right no wrong...
I already budgeted for the 50, but ended up going for the KH310.

 

[574stereo]

I've read many times that ATCs lack bass

I find most small speakers to be boomy and un-musical. You’re not going to get the party started with one of their smaller two-ways if that’s what you’re looking to do, but the low end is super musical and tight (low group delay).

I’ve been running a sub with my SCM7s for a year or so, but I’ve recently gone back to just the ATCs (no sub) and although the very deepest octave is somewhat subdued in comparison to before, it’s still there and the overall presentation is far more musical down low.

When you’re designing a small speaker, you have trade-offs when it comes to low end.

- low group delay
- extension
- ‘quantity’ of bass
- maximum SPL
- harmonic distortion

You can’t modify one without affecting the others. The more you try to push one of these parameters the more the designer has to give up on the others.

ATC prioritise low group delay and extension but not without totally compromising the other areas. Maximum SPL is very respectable for a small speaker with a 5” cone in a sealed box and I’m always surprised how much low end comes from such a small speaker but without drawing attention to itself (unlike a lot of small ported speakers). Again this is done without any of the usual tricks (resonant LF response either from a port or a cabinet which is too small for the woofer).

Does adding DSP allow you to get around these issues? No. If you use EQ to bump up the low end you’ll compromise the group delay performance, harmonic distortion and maximum SPL (and eventually IMD). Look at other speakers which do this such as the Neumanns, great speakers but not without their glaring faults (I should know, I work on KH310s regularly and used to have a pair of KH80s before the SCM7s).

Now it pure quantity of bass is what you’re looking for then there are other speakers on the market which will meet your requirements. Having done the rounds myself now with speakers from PMC, Genelec, Focal, Adam, Neumann, B&W and KEF, the ATCs have ticked the box for all the different trade offs I personally prize in listening to music.

 

[Purité Audio]

I never said that a room will correct directivity problems per se. What I mean is that if the early reflections are reduced in strength versus the direct sound reaching the listener at the listening position (which can either be achieved by absorption or distance), it will be less of a problem and even a none problem depending on how much the reflections are attenuated.

And before you come with the information again that early side wall reflections would be a good thing, I want to inform you I'm not one of those who share that view.

The early side wall reflections are down at -19 dB in my room, and that is even without using any absorption panels at the first reflection points, it's just the result of having a fairly small listening triangle and some distance to the side walls.

View attachment 338993

It would be interesting if you could post a photograph of your room from the listening position.
Keith

 

[goat76]

It would be interesting if you could post a photograph of your room from the listening position.
Keith

Why do you want to see that?

 

[lowkeyoperations]

A room doesn't correct directivity problems so to evaluate a loudspeaker performance anechoic measurements are necessary. An average room response doesn't tell anything which is the reason why equalisation cannot correct a loudspeaker with poor directivity. I can only recommend you reading Toole's comments on this thread:

Some comments from Floyd Toole about room curve targets, room EQ and more

Room curve targets Every so often it is good to review what we know about room curves, targets, etc. Almost 50 years of double-blind listening tests have shown persuasively that listeners like loudspeakers with flat, smooth, anechoic on-axis and listening-window frequency responses. Those with...

www.audiosciencereview.com

Nobody said a room corrects directivity problems. But certain listening setups can certainly remove them from audibility.

For example, listening on axis, in nearfield in a treated room can do that.

Listening on axis outside can do that too. If you’ve ever experienced the sweet spot on a pair of Funktion Ones in the middle of a forest clearing, you’ll know what I mean ;-)

Neither listening in nearfield on axis
In a well treated room, nor listening outside will improve the level of audibility of DSP induced distortion though.

 

[holdingpants01]

Nobody said a room corrects directivity problems. But certain listening setups can certainly remove them from audibility.

For example, listening on axis, in nearfield in a treated room can do that.

This actually almost never happens in reality, as there's always some kind of hard reflective surface/desk at arms length which makes directivity problems quite audible. Not to mention computer screen. I use a very small desk which fits only keyboard/mouse and volume control (80cm x 40cm), but I never saw anything like that in any other studio. The TV I have behind the speakers can't be angled towards me too much as it also reflects the sound and I use coaxial monitors with perfect directivity, it only gets worse with conventional speakers

 

[lowkeyoperations]

You often see it in mastering studios that have tiny desks with specially shaped outboard gear racks.

But yeah meterbridge nearfields on a big desk cause issues.

 

[DavidShe]

I never said that a room will correct directivity problems per se. What I mean is that if the early reflections are reduced in strength versus the direct sound reaching the listener at the listening position (which can either be achieved by absorption or distance), it will be less of a problem and even a none problem depending on how much the reflections are attenuated.

And before you come with the information again that early side wall reflections would be a good thing, I want to inform you I'm not one of those who share that view.

The early side wall reflections are down at -19 dB in my room, and that is even without using any absorption panels at the first reflection points, it's just the result of having a fairly small listening triangle and some distance to the side walls.

View attachment 338993

On your diagram it seems the first reflection bounces off the ceiling with a delay of 15ms at -19dB. The second reflection bounces off the left side wall with a delay of 30ms, also at -19dB. Why is the left wall distance different from the right wall distance? Where is the reflection from the floor? Maybe the labels should read "floor", "ceiling", "side walls", "back wall"?

 

[goat76]

I happened to stumble across a video on ATC SCM11 v2 on GR-Research's YouTube channel. If his measurements are anything to go by, the directivity looks pretty fine for that speaker.

 

[goat76]

On your diagram it seems the first reflection bounces off the ceiling with a delay of 15ms at -19dB. The second reflection bounces off the left side wall with a delay of 30ms, also at -19dB. Why is the left wall distance different from the right wall distance? Where is the reflection from the floor? Maybe the labels should read "floor", "ceiling", "side walls", "back wall"?

No, the reflection from the ceiling has a delay of 5ms at -19 dB, and the reflection from the left wall has a delay of 11ms at -19 dB. In REW, those numbers you see at the bottom are milliseconds, not meters.

The measurement is of the left speaker which is placed closer to the left wall than the right wall. I have measured all the distances and the labels are correct. I have a thick carpet on the floor and when placing a mirror on the floor there is not much of the loudspeaker that can be seen at the reflection point on the floor, thanks to my curved sofa taking most of the reflection. My listening distance to the speakers is only 204 cm.

 

[JustJones]

Anyone looking for some ATC here's a pair of SCM150 ASLT

ATC SCM150ASLT Floorstanding Active Speakers; Pair

Shop The Music Room for thousands of HiFi audio products. Saving HiFi since 2011, we are the most trusted source for audiophiles of all budgets.

tmraudio.com

SCM100ASLT

ATC SCM100ASLT Floorstanding Active Speakers; Pair

Shop The Music Room for thousands of HiFi audio products. Saving HiFi since 2011, we are the most trusted source for audiophiles of all budgets.

tmraudio.com

The big SCM300ASLT

ATC SCM300ASLT Floorstanding Active Speakers; Pair

Shop The Music Room for thousands of HiFi audio products. Saving HiFi since 2011, we are the most trusted source for audiophiles of all budgets.

tmraudio.com

 

[Purité Audio]

No, the reflection from the ceiling has a delay of 5ms at -19 dB, and the reflection from the left wall has a delay of 11ms at -19 dB. In REW, those numbers you see at the bottom are milliseconds, not meters.

The measurement is of the left speaker which is placed closer to the left wall than the right wall. I have measured all the distances and the labels are correct. I have a thick carpet on the floor and when placing a mirror on the floor there is not much of the loudspeaker that can be seen at the reflection point on the floor, thanks to my curved sofa taking most of the reflection. My listening distance to the speakers is only 204 cm.

What is the actual distance from your left speaker from the left wall?
Keith

 

[DavidShe]

No, the reflection from the ceiling has a delay of 5ms at -19 dB, and the reflection from the left wall has a delay of 11ms at -19 dB. In REW, those numbers you see at the bottom are milliseconds, not meters.

The measurement is of the left speaker which is placed closer to the left wall than the right wall. I have measured all the distances and the labels are correct. I have a thick carpet on the floor and when placing a mirror on the floor there is not much of the loudspeaker that can be seen at the reflection point on the floor, thanks to my curved sofa taking most of the reflection. My listening distance to the speakers is only 204 cm.

Ok. Thank you for the clarification.

 

[prestigetone]

I've read many times that ATCs lack bass

They do. That’s never in question. But their mids are the stuff of legends

 

[DavidShe]

Anyone looking for some ATC here's a pair of

ATC SCM100ASLT Floorstanding Active Speakers; Pair

Shop The Music Room for thousands of HiFi audio products. Saving HiFi since 2011, we are the most trusted source for audiophiles of all budgets.

tmraudio.com

The ATC SCM100ASL Pro are $20K/pair at Sweetwater.

 

[Berlin]

I've read many times that ATCs lack bass

They do. That’s never in question. But their mids are the stuff of legends

In direct comparison to a pair of Genelecs and Neumanns they are not...