1 inch CD Comparison (SEOS18) - Page 7 - AVS Forum
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Old 07-15-2013, 09:10 AM
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Originally Posted by rahula7 View Post

The importance of getting clean measurements from 100 Hz to 500 Hz cannot be emphasized enough. Once you get that range right, music sounds like music.

Interesting you say that. I totally agree. It's why I've given up on indoor measurements. The mentality that the room becomes to involved at those frequencies doesn't cut it in my opinion. It still needs to be done right.

This is a speaker I'd love to hear!
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Old 07-15-2013, 12:50 PM - Thread Starter
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Right!

Chapter 20 in Toole's book is very interesting. They asked trained listeners to draw the frequency response for loudspeakers they heard in blind listening tests. The response drawn by the listeners matched best with the on-axis anechoic frequency response of the loudspeakers. No in-room response, not a power response, no house response, no x-curves, not early reflections response, but the on-axis anechoic FR.

Our ears and brain have a great ability to listen through the room and detect the direct response from the speaker. When you improve the linearity of the loudspeaker's inherent response, it sounds better.

The power of DSP allows us to do a lot of things, but those who EQ based on the room response don't have it right, IMHO.
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Old 07-15-2013, 02:09 PM
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Kinda makes you wonder why we spend all this time making these incredibly linear loudspeakers and then let Audyssey and MCACC totally change the frequency response...

There was a recent podcast hosted by Scottt Wilkinson where the guest, Paul Hales, discussed this issue from a similar perspective and basically said don't let these room EQ programs change the FR of your speakers, provided you are starting with a linear speaker from the outset. It made me a believer and your comments seem to confirm this approach.

Mike
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edit - link and guest name added
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Old 07-15-2013, 02:42 PM
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I don't let YPAO touch my eq, because I'm smarter than it is. But I do use the programmable eq in it to do things for me that extra cross over components would make a hassle.

Audessay is less friendly in that regard afaik.

But ya, didnt hear the podcast, but sounds like Scott is right. Gotta be careful what those auto eqs are doing. Which is probably why so many people dislike them. Of course some people do like them. They probably "fix" some speakers too.
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Old 07-16-2013, 08:22 AM
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I think it is more complex than "You should eq room" or "You should never EQ room". The toole chapter, as I recall it, demonstrated the importance of on-axis, but not that off-axis response is insignificant. The question is how do you improve the overall listening experience which is still a combination of on-axis and off-axis. Just because the ear can filter through some of the off-axis to determine a general frequency response that doesn't mean that it should be left untouched. It is a question of tradeoffs. Room EQ is not free in the sense that you are altering linear on-axis response. The question is whether the tradeoff is worth it.

I'd also say that generally with directivity controlled speakers, auto-eq is more detriment than benefit. At least that is the case with typical consumer room eq (I've had much better luck with dirac).

What I'd like to see would be an option to only have Audyssey cover a certain bandwidth like the modal region and leave the rest alone.

Also, don't read the Toole research to say that on-axis is so dominant that off-axis is unimportant. The fact is that it is not all that difficult to get on-axis response flat. In my opinion, the difference between good and great with speakers is the off-axis response. The key is getting exceptional off-axis response without sacrificing on-axis linearity. I guess I'm preaching to the choir on that one since most guys here are using horns.
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Old 07-17-2013, 06:55 AM
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How low can you cross the DNA-360 versus a BMS-4550 on the Seos-15 versus the Seos-12, and also the Seos-18? Is the Seos-18 capable of crossing all that much lower than the Seos-15?
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Old 08-04-2013, 11:17 AM
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Hi ho!I have a pair of BA-750's and SEOS 18's here and did some quick measuring yesterday. I experienced some ripple below 1 kHz, which was almost gone when I measured it in a foam pit facing upwards. So probably a combination of ground reflection and edge diffraction. I'll try to do some better ones later this week. Measuring distance was 2m and sound level very high to supress noise. Probably more than 100db @ 1m. So take distortion and frequency response below 1kHz with a grain of salt for now, they are most likely better than the measurement is saying. 1/24 smoothing.



I'll come back with distortion graphs on a EQ'ed unit with a XO in place and directivity later.
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Old 08-04-2013, 04:45 PM
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Drool. I'd love a pair of those eek.gif
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Old 08-04-2013, 04:58 PM
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Quote:
Originally Posted by FredrikC View Post

Hi ho!I have a pair of BA-750's and SEOS 18's here and did some quick measuring yesterday. I experienced some ripple below 1 kHz, which was almost gone when I measured it in a foam pit facing upwards. So probably a combination of ground reflection and edge diffraction. I'll try to do some better ones later this week. Measuring distance was 2m and sound level very high to supress noise. Probably more than 100db @ 1m. So take distortion and frequency response below 1kHz with a grain of salt for now, they are most likely better than the measurement is saying. 1/24 smoothing.



I'll come back with distortion graphs on a EQ'ed unit with a XO in place and directivity later.

Thanks for the measurements. I have the BA-750/SEOS 18's too, along with the TD15M's. I'll be interested in following your build process. Unfortunately, I'm in the middle of a kitchen/living room remodeling project so the speaker project is on the back burner...for now.

-Roy
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Old 08-04-2013, 08:26 PM
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Those are just excuses rajacat!
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Old 08-05-2013, 10:12 AM
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Quote:
Originally Posted by tuxedocivic View Post

Those are just excuses rajacat!

The problem is, if I build the speakers now, I'll have nowhere to place them.redface.gif However, I'm a bit further along in the remodel than appears in this photo and the end will be coming soon.smile.gif I'm creating one big room by knocking some walls down so that the kitchen, dining area and living room are as one. A big project it is. I'm building my kitchen cabinets from scratch ... a whole new kitchen. New flooring everywhere. All new windows, etc., etc.

The reason I got involved in the SEOS project is that I realized I'd need new, larger speakers to fill this 15' x 35' room.

...Roy

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Old 08-05-2013, 11:23 AM - Thread Starter
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Thanks for the measurements Fredrick! There is some ripple below 1 kHz, but it might be reflection induced. Distortion does climb above the -40db level below 1 kHz. Still, that's quite a useful response. I will probably get a pair of the BA-750s when they become available.

@Roy, that looks like a huge undertaking!
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Old 08-05-2013, 02:42 PM
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[quote name="rahula7" url="/t/1477921/1-inch-cd-comparison-seos18/180#post_2359752
@Roy, that looks like a huge undertaking![/quote]

Yes, it's a very large project. Since I'm doing all this disruptive work, I've toyed with the idea of building my SEOS-18/BA750/TD15M's speakers into the corner of the room. That might be both cheaper and easier than building the boxes. The corners would provide the optimum 45 degree toe in.
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Old 08-06-2013, 08:57 AM
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Due to bad weather I couldn't measure outside today, so I set up inside and in the middle of the room and aimed the WG at the celing. Then I used gating to remove the celing reflection. I made two different XO's. one following a 4th order LR and one 6th order LR.

Level was calibrated close to 90db average to alow better comparison with loudpseaker databases like zaph & others. Based on this the earlier measurement was at about 105db.



Here is a comparison of 4th vs 6th order XO.


CSD indicating quite alot of break up @ 8-9khz and 16-19kHz.

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Old 08-06-2013, 12:54 PM - Thread Starter
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Thanks!

Is that an 800 Hz crossover? Distortion still looks high at 1 kHz. It gives the sound the bright, syruppy quality IMO.

It's useful to specify the distance at which the measurement was made along with the SPL. For example, 90db at 1m is 6db less than 90db at 2m.

Also, it would be nice if you could overlay the raw response with the crossover response. And show with 1/20th octave smoothing.

ARTA's distortion graphs have never made sense to me. The audibility of increasing distortion with lower frequency is not reflected in ARTA's plot.
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Old 08-06-2013, 02:31 PM
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Quote:
Originally Posted by rahula7 View Post

Thanks!

Is that an 800 Hz crossover? Distortion still looks high at 1 kHz. It gives the sound the bright, syruppy quality IMO.

It's useful to specify the distance at which the measurement was made along with the SPL. For example, 90db at 1m is 6db less than 90db at 2m.

Also, it would be nice if you could overlay the raw response with the crossover response. And show with 1/20th octave smoothing.

ARTA's distortion graphs have never made sense to me. The audibility of increasing distortion with lower frequency is not reflected in ARTA's plot.

Yes, that is an 800hz XO. I calibratet the level to about 90db @ 1m with a 1kHz sine wave, but measurement distance was 140cm.
I have posted the raw response further up with 1/24. That measurement is outdoors with 15 more db gain from the amp. I tried to overlay them in HOLM. But the program crashes when I use the import function?
Indoors isn't very usefull without gating, there is no aditional smoothing on the graph except for the gating.
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Old 08-07-2013, 10:16 AM
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Horisontal directivity, 1/12 smoothing normalized to on-axis:


Not normalized:
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Old 08-07-2013, 10:55 AM - Thread Starter
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Those are truly great polars. Thanks for the measurements.

I'm trying to understand the not normalized plot. Why does it show a narrow response below 1 kHz? Not sure I understand what ARTA is doing there.

The measurements look really good. What is your setup for making the off-axis measurements? Also, what is the axis of rotation? Front of waveguide, point where driver meets waveguide or somewhere further back?

Again, really appreciated!
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Old 08-07-2013, 11:56 AM
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I was wondering the same. My thought is something like: the not normalized one doesn't acount for falling response. So if this was a fullrange speaker it would probably look similar as the normalized one. But since level is faling below 1khz. that means that 800Hz @ 45 degrees is lower in level than 45 degrees at 4kHz and there for it appears to narrow. But it narrows the same amount both of and on axis, there for directivity is still held constant, which is clear in the normalized one, since there the reference is the on axis level at the given frequency, not absolute level. Did this make any sense? Absolute level vs level relative to on-axis level at the give frequency is the keyword.


I made a rotating rig from an IKEA TACO serving plate xD. Just screwed it to a larger plate. Then I drew a circle around it and marked of the different angles. Probably not 100% correct, but I think the largest error would be geting the mic at excactly 0 degrees in the first place.

Axis if rotation was horn entry. I didn't have time to do vertical. Will need to modify the TACO rig some more biggrin.gif

Listening impressions from this combo will be very short. I think subjective description only has value if you have a good reference which you can A-B test against with minimal time between. I happen to have such a setup playing now, but the reference is a Tang Band5" full range speaker.... The CD-Waveguide outperforms it easliy, leaving the fullrange sounding compressed, hollow, and coloured. The fullranger images better. But mostly because the SEOS is sitting on top of two chairs to the side of the fullranger, and the XO is not at all optimal. No time or phase coherence. It's also difficult to here what is the fullranger and what is the waveguide when I run them together. It's obvious the fullranger can't keep up. A 12/15" mid or dual 8" are probably a better match in terms of dynamics, directivity and distortion below 300hz.

A more interesting A-B scanrio would be with another well know horn/driver combo siting directly above/below it, and some cabable and similar hardware from 800hz and down. This is all possible to do with todays DSP's.

Another thing I would like to mention is how closely the SEOS horn measures outside vs inside. If I use gating or smoothing to remove some wrinkles from room interaction they look almost identical. The fullranger or normal dome tweeters do not.
Here is a measurement from the listening position with same EQ and XO as before 1/12 smoothing:



Truly a product of the narrow and uniform directivity I think.
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Old 08-07-2013, 03:05 PM - Thread Starter
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Quote:
Originally Posted by FredrikC View Post

I was wondering the same. My thought is something like: the not normalized one doesn't acount for falling response. So if this was a fullrange speaker it would probably look similar as the normalized one. But since level is faling below 1khz. that means that 800Hz @ 45 degrees is lower in level than 45 degrees at 4kHz and there for it appears to narrow. But it narrows the same amount both of and on axis, there for directivity is still held constant, which is clear in the normalized one, since there the reference is the on axis level at the given frequency, not absolute level. Did this make any sense? Absolute level vs level relative to on-axis level at the give frequency is the keyword.

Yes, that makes perfect sense. Thanks! The normalized, but not heavily smoothed, is a much better representation of polars then.

Quote:
I made a rotating rig from an IKEA TACO serving plate xD. Just screwed it to a larger plate. Then I drew a circle around it and marked of the different angles. Probably not 100% correct, but I think the largest error would be geting the mic at excactly 0 degrees in the first place.

Axis if rotation was horn entry. I didn't have time to do vertical. Will need to modify the TACO rig some more biggrin.gif

I need to rig up something similar. Got any pics? Feel free to post them here.

Quote:
Truly a product of the narrow and uniform directivity I think.

Indeed.
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Old 08-08-2013, 05:49 PM
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Wow!
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Originally Posted by FredrikC View Post

Horisontal directivity, 1/12 smoothing normalized to on-axis:


Not normalized:

Noah
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Old 08-17-2014, 10:59 AM
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directional mics for indoor measurements?

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Originally Posted by rahula7 View Post
Right!

Chapter 20 in Toole's book is very interesting. They asked trained listeners to draw the frequency response for loudspeakers they heard in blind listening tests. The response drawn by the listeners matched best with the on-axis anechoic frequency response of the loudspeakers. No in-room response, not a power response, no house response, no x-curves, not early reflections response, but the on-axis anechoic FR.

Our ears and brain have a great ability to listen through the room and detect the direct response from the speaker. When you improve the linearity of the loudspeaker's inherent response, it sounds better.

The power of DSP allows us to do a lot of things, but those who EQ based on the room response don't have it right, IMHO.
just reread the thread as I have SEOS18s on order
On this post, it struck me: what if we measured indoors with a directional mic?

I did a little research:

Line Microphones
When miking must be done from even greater distances, line or "shotgun" microphones are often the best choice. Line microphones are excellent for use in video and film, in order to pick up sound when the microphone must be located outside the frame, that is, out of the viewing angle of the camera.

The line microphone uses an interference tube in front of the element to ensure much greater cancellation of sound arriving from the sides. Audio-Technica line microphones combine a directional ("gradient") element with the interference tube to increase cancellation at the rear as well.

As a general design rule, the interference tube of a line microphone must be lengthened to narrow the acceptance angle and increase the working distance. While shorter line microphones may not provide as great a working distance as their longer counterparts, their wider acceptance angle is preferred for some applications, because aiming does not need to be precise. Some A-T shotgun mics employ an exclusive design (U.S. Patent No. 4,789,044) that provides the same performance with an interference tube one-third shorter than conventional designs.

How Do They Sound?
From a distance of two feet or so, in an absolutely "dead" room, a good omni and a good cardioid may sound very similar. But put the pair side-by-side in a "live" room (a large church or auditorium, for instance) and you'll hear an immediate difference. The omni will pick up all of the reverberation and echoes - the sound will be very "live." The cardioid will also pick up some reverberation, but a great deal less, so its sound will not change as much compared to the "dead" room sound. (This is the "Distance Factor" in action.)

The above suggests that a line or "shotgun" mike would work best but even a cardiod mic would help by ignoring reflections from the rear of the room. This might be an expensive way to avoid carrying the speakers outside but my back may be worth the bucks. Has this been done before?

Jack
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Old 08-17-2014, 04:51 PM - Thread Starter
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Hi, this could be a valid approach. I remember some discussion about microphones in D'Appolito's book, but can't remember if directional mics were proposed as a solution to mitigating room reflections. I'm away this week on travel, so don't have the copy of D'Appolito in front of me.

Give it a shot. Some reading on the recording forums suggests that shotgun mics could result in comb filtering. This could be a problem if you're doing measurements, but may not be a problem in recording. You would still need a calibration file, I guess.

I don't have much experience in this area, so don't know what it would look like. Give it a try and let us know. You could also ask around the recording forums and see what they think. Someone might even run the experiment for you because they may have the mics at hand.

If it does work, even with some compromises, it would be a big break for measurements in small rooms. Although, I cannot imagine that this would not have occurred to someone like D'Appolito when he wrote the book.

Last edited by rahula7; 08-17-2014 at 04:55 PM.
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Old 08-17-2014, 05:07 PM
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rahula's post is noteworthy. not sure how that sits vis-à-vis the observation that in a typical room an overall slightly downward tilted frequency response tends to be perceived as preferable, which would suggest that sound power, at least in some sense, is figuring into the mix.

Listen. It's All Good.
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Old 08-17-2014, 08:28 PM
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Quote:
Originally Posted by rahula7 View Post
Hi, this could be a valid approach. I remember some discussion about microphones in D'Appolito's book, but can't remember if directional mics were proposed as a solution to mitigating room reflections. I'm away this week on travel, so don't have the copy of D'Appolito in front of me.

Give it a shot. Some reading on the recording forums suggests that shotgun mics could result in comb filtering. This could be a problem if you're doing measurements, but may not be a problem in recording. You would still need a calibration file, I guess.

I don't have much experience in this area, so don't know what it would look like. Give it a try and let us know. You could also ask around the recording forums and see what they think. Someone might even run the experiment for you because they may have the mics at hand.

If it does work, even with some compromises, it would be a big break for measurements in small rooms. Although, I cannot imagine that this would not have occurred to someone like D'Appolito when he wrote the book.
D'appolito says that directional mics aren't as smooth in FR as omni's and have a proximity effect that raises the bass response. He favors omnidirectional condenser mics for their accuracy. After discussing mic types he goes on to discuss measurement techniques to work around reflections without directional mics. Today we all use gated impulse response at the expense of low frequency information. For the lows, we do near field measurements of woofers and ports and blend them into the gated impulse response. Thus, the argument that directional mics aren't needed and the often expressed opinion that outdoor measurements are better.

Gated impulse does fine for the crossover between mids and tweeter/CD but what about the woofer of 3 way? The crossover would likely be within the inverse of the gate time and might even be in the modal region. I think the W-M crossover is where a directional mic might provide some value.

It looks like a choice between a cardiod and a shotgun mic. The cardiod has a wide frontal lobe with flat frequency response and good rejection to the rear. For a directional source it might be the best but it wouldn't reject lateral or floor or ceiling reflections. A shotgun mic could have sufficient directionality for that but would need more calibration and, if I read low resolution graphs correctly, its directionality is a function of frequency. But if measuring a WMTMW, that is OK because the beamewidth widens at low frequency, as it needs to.

Something interesting to think about...

Jack
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Old 08-17-2014, 10:50 PM - Thread Starter
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Quote:
Originally Posted by JackNC View Post
Gated impulse does fine for the crossover between mids and tweeter/CD but what about the woofer of 3 way? The crossover would likely be within the inverse of the gate time and might even be in the modal region. I think the W-M crossover is where a directional mic might provide some value.
I could not agree with you more. I've been working on a corner loaded expanding array (ala David Smith's Snell XA expanding array). The measurements have to be taken in-room and it is very hard to eliminate the ceiling reflection. The other reflections are not there by design. I'm working on some ceiling absorbers to absorb that reflection. The most difficult part was and still is the crossover between the middle woofers at the KEF mid driver. Gating does not give enough resolution at 500 Hz.

Quote:
It looks like a choice between a cardiod and a shotgun mic. The cardiod has a wide frontal lobe with flat frequency response and good rejection to the rear. For a directional source it might be the best but it wouldn't reject lateral or floor or ceiling reflections. A shotgun mic could have sufficient directionality for that but would need more calibration and, if I read low resolution graphs correctly, its directionality is a function of frequency. But if measuring a WMTMW, that is OK because the beamewidth widens at low frequency, as it needs to.

Something interesting to think about...

Jack
Yes, this does sound interesting.
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Old 08-18-2014, 06:47 AM
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Hi Rahula:
I had seen your thread over at DIYA but didn't put 2 and 2 together here. Why not a SEOS 18 in the middle instead of a KEF?

I'm going in the same direction as you with WMTMW but crossing over per the D'Appolito criterion, where CTC distance = 2/3 lambda, which works out to 950 Hz and 169 Hz. I don't understand the difference between expanding line array and D'App. I bought SoundEasy hoping it would predict in room polars for me but haven't gotten very far with it yet.

In my design T is a SEOS18 and the Ms are offset driver midhorns. So far at least, I have the T at ear height instead of midwall. I see from the geometry that if I move it to half wall like yours, its well within the MTM vertical beamwidth. I'm pondering the consequences of that. I would get more volume for the woofers, which would be nice but I wouldn't want to force the crossover to the woofers any lower. I might be able to get them to 2' and 6' with benefits in cancelling some modes....

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Old 08-18-2014, 10:52 AM - Thread Starter
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Originally Posted by JackNC View Post
Hi Rahula:
I had seen your thread over at DIYA but didn't put 2 and 2 together here. Why not a SEOS 18 in the middle instead of a KEF?

I'm going in the same direction as you with WMTMW but crossing over per the D'Appolito criterion, where CTC distance = 2/3 lambda, which works out to 950 Hz and 169 Hz. I don't understand the difference between expanding line array and D'App. I bought SoundEasy hoping it would predict in room polars for me but haven't gotten very far with it yet.

In my design T is a SEOS18 and the Ms are offset driver midhorns. So far at least, I have the T at ear height instead of midwall. I see from the geometry that if I move it to half wall like yours, its well within the MTM vertical beamwidth. I'm pondering the consequences of that. I would get more volume for the woofers, which would be nice but I wouldn't want to force the crossover to the woofers any lower. I might be able to get them to 2' and 6' with benefits in cancelling some modes....

Jack
Interesting design. How does SoundEasy predict polars? Can you specify drivers as coaxials or horns? How does it account for the SEOS horn, for example?

The KEF is a coaxial unit, i.e., no lobing between the mid and tweeter. The hope is that the M to W CTC can be reduced to less than 1/2 wavelength and lobing will mostly be eliminated. The response will be even in the vertical direction. With the SEOS-18, it will be a struggle to eliminate the vertical lobes because the width of the horn in the vertical direction is usually larger than 1/2 wavelength at the crossover frequency.

Regarding the expanding line array, here's Dave's explanation:
"It was important to me that I achieve a system with smoother directivity and without the usual response nulls off axis. At Mac I did a THX system with 3 tweeters in a short row, not a line array so much as just a short multi-element array. If the center tweeter was used for its full range and the outer tweeters were progressively rolled off I could get something that was lobe free. It was directivity without “pain”. At Snell I just extended that over a number of sections and a wider frequency range. I was using Peter Shuck’s early Xopt crossover/system modeling software and was finding ways to stack elements tight and roll off each section in particular ways that gave very well behaved directivity. I found I could achieve flat response on axis, less than a dB or so droop at +-15 degrees vertical and a totally uniform 6dB or so shelving at +- 30-40 degrees. This was exceedingly well behaved. In essence, with the smooth transition from the inner tweeter to adjacent mids, to surrounding woofer, you are making a system that has an effective length proportionate to radiated wavelength. Looking for a marketing hook, we called it an eXpanding Array, meaning that its effective length expanded as you went down in frequency (that seemed more positive than it contracting as you go up in frequency!)

So with JBL I worked with constant directivity wave guide devices, at McIntosh with medium and long line arrays and at Snell with highly optimized symmetrical arrays. Of the 3 approaches I think the symmetrical array is best. Response is very well behaved and the directivity increase is about right, not as extreme as it is with the long arrays."

You can read about it in the interview here (page 1 is interesting too):
http://www.tnt-audio.com/intervis/david_smith2_e.html

With the coaxial unit, the most difficult part of the design, which is getting the tweeter very close to the mids, has been eliminated. With the corner array, I can get control in both the vertical and horizontal directions to a very low frequency. It breaks down a little at the KEF unit, which is just a single driver, but it is better than most other designs at eliminating the vertical reflections. Also, the KEF coaxial is a great unit. Quite smooth in response and low in distortion.

I did the horn thing. I have a SEOS-24, 18 and 12 and a large tractrix. I have the large Altec VOTTs as well. But I'm not too convinced with the horns, too much expense and size, and too much complexity for little to no benefit. With the SEOS horns, I never could get the balance in the highs quite right. If I make on-axis flat, it sounds a little bright, but if I provide droop, the balance sounds ok, but then some detail is missing. I think a rising directivity is appropriate in most small rooms. You don't want it to be too narrow, but constant seems too bright to me. Of course, YMMV, depending on your room size, amount of absorption and where it is located.

The corner array design I have right now was just an experiment, but it has been quite enjoyable. This is the way to go in my opinion: corner line arrays, or line arrays in general. The corner speakers gave me my room back, as in the floor area. They are much more social as well, whereas horns tend to be large and asocial. If you listen in stereo only then you want the side wall reflections. It adds some ambiguity and a pleasant sense of envelopment to the sound.
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Old 08-18-2014, 11:08 AM - Thread Starter
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Originally Posted by LTD02 View Post
rahula's post is noteworthy. not sure how that sits vis-à-vis the observation that in a typical room an overall slightly downward tilted frequency response tends to be perceived as preferable, which would suggest that sound power, at least in some sense, is figuring into the mix.
If you study the history of the cinema curves, then they are based on steady-state measurements, not gated or anechoic measurements. The problem with having a single curve was just that: it was a single curve and it needed to be adjusted for every theater depending on the size of the theater and directivity of the speakers. This is true in small rooms as well. There is not one curve you can rely on. It is the directivity of your speakers combined with the size of the room, the amount of absorption and where it is located that will give the right balance. But again, in my experience, you should not adjust this by sacrificing flat on-axis response, rather, by designing the speakers to have the right directivity, or given the speakers adjusting the room absorption to achieve the proper balance.

To me, making the response of the SEOS horns droop to make it sound less bright was an improvement, but there was a definite loss of detail that I did not like either. It turns out that the rising directivity of traditional cone and dome speakers is just right with the absorption found in typical small rooms.

Besides, if you turn on ARTA and measure the steady-state response, almost always you will get a drooping response. The HF absorption will take care of it.
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Old 08-18-2014, 12:12 PM
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re'Interesting design. How does SoundEasy predict polars? Can you specify drivers as coaxials or horns? How does it account for the SEOS horn, for example

Sound easy doesn't model horns well but it does allow you to create a BEM model of the room. I wanted to see how the approximated speaker would work in the room and perhaps even model various treatments. In the modal region the midhorns have lost pattern control so its probably sufficient to model them as rectangular pistons of the size of the midhorn mouth. As I said, haven't gotten there yet.... and may never because now I'm more interested in building than simulating.

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