Horn vs. Waveguide

[gedlee]

[Not gonna hold it against you, tho, as Earl's having some difficulty with that himself.... 😉 ]

I think you are a bit full of yourself. I'll stand behind my position. The only trouble that I am having is with people who refuse to budge on theirs.

Help me, now, Earl EQ's flat at 22.5°, the listening axis. What are the off-axis angles generating the enhanced image rendition at each end of the couch?

Thats not really true, but beside the point. The idea is that for setups like mine, which I would contend are not only typical but prefered, the typical listener (on the couch) will be between about 10 degrees and about 35 degrees. Worst case 0 and 45 degrees, but that would not be very common. This means that the response needs to be smooth and uniform (above some frequency) over these angles. One point that is never made, is that my design actually wastes the other side of axial since no one is ever there. This could be fixed, but then I would have to make left and right speakers - not impossible, just not as easy.

Is it possible to have a conversation with you that is not personal and critical or sarcastic?

 

[markus76]

The first part's easy: because we like it.

Not me – at least not in sound reproduction from 2 speakers. Have you ever attended a classic concert? Never heard that from a stereo setup. Let stereo do what it is really capable of and leave spaciousness to multichannel.

I agree that early ipsilateral (near wall) reflections degrade not only localization, and also, spectral balance, and there is good reason to minimize them, but it's possible to isolate the ASW cues and enhance it without the deleterious consequences of conventional approaches.

How do you want achieve that?

Imaging and soundfield don't have to be mutually exclusive.

There are people that claim the opposite.

Best, Markus

 

[gedlee]

Nice quote from Newell:


(Recording Studio Design, 2nd Edition)

Markus

Yes, thats a good point.

I have recently been having some side E-mails with a guy in Belgium and Jens Blauert about very early reflections, imaging and spatiuosness. Dr. Blauert does believe that there is a tradeoff that has to be made between spatiousness and image as regards the <10-15 ms reflections. That one can't have it both ways. This would explain why a listener group, like Floyd's, who put spaciuosness very high in the "preference scale" would find every early reflections "preferable", even if this same thing degrades "imaging". It may well be that these two things will always have to be traded off and that there will never be a "one size fits all". Its hard to say.

 

[markus76]

I think you are a bit full of yourself.

I think you have a lot in common: http://www.diyaudio.com/forums/showthread.php?postid=1833672#post1833672

This could be fixed, but then I would have to make left and right speakers - not impossible, just not as easy.

This is exactly what I need – build it, I'll buy it.

Best, Markus

 

[ZilchLab]

Is it possible to have a conversation with you that is not personal and critical or sarcastic?

Actually, I was hoping you'd inform Patrick that your definitive criterion for CD is that response curves between 0° and 30° should fall within +/- 2 dB, and that driver/waveguide combinations performing within this spec are certainly not "defective," as he posits.

Have you ever attended a classic concert? Never heard that from a stereo setup. Let stereo do what it is really capable of and leave spaciousness to multichannel.

The AR/Allison wide dispersion school asserts they have it knocked. I tell them nobody has given a whit for 30 years.

[They're pissed at me too. 😉 ]

How do you want achieve that?

Minimize the very early first ipsilateral reflection with CD, and enhance a later >10 ms first contralateral, as Earl suggests.

Here's an early approach by Ken Kantor when he was with AR:

http://www.kenkantor.com/publications/magic_speaker/magic_speaker.pdf

 

[catapult]

I think imaging is, to some extent, an artificial audiophile construct. When I sit in a club listening to a live acoustic band, I can't really close my eyes and point to each instrument other than it's just 'somewhere over there.' And it's even worse if it's amplified -- they may have their speakers sitting anywhere.

 

[gedlee]

This is exactly what I need – build it, I'll buy it.

Best, Markus

Thats one each, another 99 and we are all set! Honestly Markus, its not likely to happen, too complicated. Its just interesting to think about totally controlled directivity in all directions.

 

[markus76]

I have recently been having some side E-mails with a guy in Belgium and Jens Blauert about very early reflections, imaging and spatiuosness. Dr. Blauert does believe that there is a tradeoff that has to be made between spatiousness and image as regards the <10-15 ms reflections. That one can't have it both ways.

Blauert said that? Very interesting. A statement I always wanted to read in one of his books. I've been to a classic concert lately (Jordan Hall, Boston). Sound was ethereal but localization was reduced to left, middle and right space. Early reflections in that space are surely >15ms.

It may well be that these two things will always have to be traded off and that there will never be a "one size fits all". Its hard to say.

That is exactly what multichannel is about. Spaciousness can finally become part of the recording. This is how it should have been right from the start.

Best, Markus

 

[Patrick Bateman]

Actually, I was hoping you'd inform Patrick that your definitive criterion for CD is that response curves between 0� and 30� should fall within +/- 2 dB, and that driver/waveguide combinations performing within this spec are certainly not "defective," as he posits.

When did I say that the waveguide you're using is defective?

Oh yeah, that's right, I didn't.

http://www.diyaudio.com/forums/sear...esults&searchid=1164442714&sortby=&sortorder=

You've posted some good stuff zilch, I wish you'd stop being a troll though.

 

[markus76]

Minimize the very early first ipsilateral reflection with CD, and enhance a later >10 ms first contralateral, as Earl suggests.

That killed localization nearly completely for me. Even had – pretty stable – phantom sources from the right ceiling corner behind...

Best, Markus

 

[markus76]

I think imaging is, to some extent, an artificial audiophile construct. When I sit in a club listening to a live acoustic band, I can't really close my eyes and point to each instrument other than it's just 'somewhere over there.' And it's even worse if it's amplified -- they may have their speakers sitting anywhere.

It's not "an artificial audiophile construct", it's simply what stereo is! Go to that club or buy dummy head recordings or wait for wave field synthesis to happen if you want to have (virtual) reality.

Best, Markus

 

[ZilchLab]

YO, Patrick!

AR3a tweeter polar response.

Have no illusions it performed like this in the product, tho:

 

[xpert]

Blauert said that? Very interesting. A statement I always wanted to read in one of his books.

Ain't that a bit pathetic? If it was really true, we knew that for long. Blauert believed it, Mr. Geddes reported. That implies he doesn't know and has not made an attempt do reveal the secret. Do I read it right?

Stereo seems after decades of commercializing as an open field for basic improvements. I can't stand it.

In Germany we have some standarts regarding studio technology. As a listener to serious recordings - no pop for instance - one can be sure to reproduce the recording session at home if home goes with the standart. What better can it be? Adjust the volume and enjoy.

ciao

 

[ZilchLab]

When did I say that the waveguide you're using is defective?

Oh yeah, that's right, I didn't.

Nope, it was XT1086:

That's the problem in the horizontal axis of this waveguide; all the curves are nearly identical to the on-axis response.

Admittedly, I'm splitting hairs here, but the vertical curves are noticeably better than the horizontal. (assuming we want the response to fall off-axis.)

Earl won't get specific about the angles of interest, but they're easy to calculate....


********
Here's more complete AR3a polars as measured by Roy Allison hizself:

 

[xpert]

YO, Patrick!

AR3a tweeter polar response.

Have no illusions it performed like this in the product, tho:

That ripples, is it HOM? 🙄 First it was HOM, then ripples, now directivity. If I remember it o/k its due an error of someone who took 6dB for a half. The XT1086 has the same directivity issue as every CD device, including Geddes'. Narrowing in the first octave, then widening again up to ~10kHz. JBL biradials swap horizontal with vertical up there. All in all hassle while voicing the speaker. If someone would have a cure to that?!

 

[ZilchLab]

A compression driver with a 3" diaphragm is struggling to reach 15khz. That's why a TAD 2001 uses a beryllium diaphragm, and costs a thousand dollars.

Here we have a fourty dollar tweeter on a twelve dollar waveguide with response that rivals a TAD.

If there's anything else out there at this price point with comparable performance, I don't know what it is.

You're not paying attention, obviously.

Again, what is the tweeter?

"... rivals a TAD?"

Would that be Porsche 911 or Sex Pistols yer smokin' there? 😉

 

[Patrick Bateman]

You're not paying attention, obviously.

Again, this isn't AudioKarma. You can troll over there and one of your sycophants will back you up. Take your insults somewhere else.

Again, what is the tweeter?

"... rivals a TAD?"

Would that be Porsche 911 or Sex Pistols yer smokin' there? 😉

And another troll. You quoted me out of context. Nice try!

 

[catapult]

It's not "an artificial audiophile construct", it's simply what stereo is! Go to that club or buy dummy head recordings or wait for wave field synthesis to happen if you want to have (virtual) reality.

Best, Markus

Stereo is whatever we choose it to be in our homes. I like a big soundstage but I'm less concerned with pinpoint imaging. I guess that's why I like dipoles so much. 🙂 Multichannel would be great if DVD-A wasn't dead and SACD wasn't gasping its last breaths. Mostly we're stuck with trying to make stereo sound good.

 

[ZilchLab]

Is it possible to have a conversation with you that is not personal and critical or sarcastic?

Oh, Poo.

It was funny, and you know it. 😀

Again, this isn't AudioKarma. You can troll over there and one of your sycophants will back you up. Take your insults somewhere else.

You're flooding this thread with misinformation and inane assertions.

I'm calling you on it, is all.

Have you nothing of substance to offer to the discussion?

You like Summas. For all you know, so do I.

Was there something else?

 

[Patrick Bateman]

Oh, Poo.

It was funny, and you know it. 😀




You're flooding this thread with misinformation and inane assertions.

I'm calling you on it, is all.

For every valuable contribution that you make, there are five that fall into this bucket:

"a troll is someone who posts controversial, inflammatory, irrelevant or off-topic messages in an online community, such as an online discussion forum or chat room, with the primary intent of provoking other users into an emotional response or to generally disrupt normal on-topic discussion"

Have you nothing of substance to offer to the discussion?

You like Summas. For all you know, so do I.

Was there something else?

Why would you like the Summas - you've never heard them. There are only three or four people on this thread who have.

The difference between you and everyone else here is that you and xpert are the ones bashing something you've never heard. Everyone else here is trying to sort out the advantages of waveguides.