…Can you do some additional explanations what we can see there?….etc + Dave and Lynn….
Hi all,
A lot of questions … For the moment Im too occupied to write extensive explanations, but if of any help; The ArraySHOW program is free and available from here:
http://www.electrovoice.com/tech-library.php?pt=3
Be sure to get version 1.1 build 63 as it works well almost without bugs.
Some further reading can be found at: http://www.prosoundweb.com/install/synaudcon/tt26_3/tt26_3.php
The main purpose of this program is the use for speaker set-ups using polar data from real measurements.
I mostly use the provided point source element for other various purposes like the transferring of my own real driver polar measurements to ArrayShow ….
Here is a link that might give an inspiration, addressing the part of ‘Behaviour of the cone in the frequency range’:
http://www.far-audio.com/modelisation.php
Im sorry you’ve found the resolution of my gif’s to low. I cut the first gif picture into 5 pieces and added a bunch. See the submitted pictures.
Tell me if some one wants any of the other to be magnified. It will take some time, as I don’t have saved any higher resolution copies, I have to redo all.
b
1(14)
Hi all,
A lot of questions … For the moment Im too occupied to write extensive explanations, but if of any help; The ArraySHOW program is free and available from here:
http://www.electrovoice.com/tech-library.php?pt=3
Be sure to get version 1.1 build 63 as it works well almost without bugs.
Some further reading can be found at: http://www.prosoundweb.com/install/synaudcon/tt26_3/tt26_3.php
The main purpose of this program is the use for speaker set-ups using polar data from real measurements.
I mostly use the provided point source element for other various purposes like the transferring of my own real driver polar measurements to ArrayShow ….
Here is a link that might give an inspiration, addressing the part of ‘Behaviour of the cone in the frequency range’:
http://www.far-audio.com/modelisation.php
Im sorry you’ve found the resolution of my gif’s to low. I cut the first gif picture into 5 pieces and added a bunch. See the submitted pictures.
Tell me if some one wants any of the other to be magnified. It will take some time, as I don’t have saved any higher resolution copies, I have to redo all.
b
1(14)
Attachments
Good stuff, especially the last three charts! I noted the comment in the last chart about reflections in the 0~700 uSec region degrading stereo image perception - exactly right! Those distances aren't large - that's 10 inches or 25 cm, as you like.
Unfortunately, not only are sharp-edged speaker cabinets the offenders here, but so are closely-spaced arrays, when you work out the arrival-time discrepancies of a straight-line array. That's why I only want to use all of the drivers together at the lowest frequencies (below 125 Hz), first low-passing the 15" driver closet to the floor, then low-passing the driver above that, etc. I'd like to thank Zaph and Jeff Bagby for the "cascade" crossover that would be useful for the 2.5.5 ... n LF array.
Preventing reflections in the 0~700 uSec region is also one more reason to use curved edges on a dipole as well as heavy wool felt on the back surface and vertical mounting struts.
Unfortunately, not only are sharp-edged speaker cabinets the offenders here, but so are closely-spaced arrays, when you work out the arrival-time discrepancies of a straight-line array. That's why I only want to use all of the drivers together at the lowest frequencies (below 125 Hz), first low-passing the 15" driver closet to the floor, then low-passing the driver above that, etc. I'd like to thank Zaph and Jeff Bagby for the "cascade" crossover that would be useful for the 2.5.5 ... n LF array.
Preventing reflections in the 0~700 uSec region is also one more reason to use curved edges on a dipole as well as heavy wool felt on the back surface and vertical mounting struts.
?Hi All,
I've followed this thread with great interest. I'll toss in one data point, if I may. My current system is shown here: http://www.diyaudio.com/forums/showthread.php?s=&threadid=69906&highlight="unity+horn" The crossover arrangement is described in the last couple of posts on the second page. I have filled the horns with open cell foam, per Earl Geddes and that pretty much eliminated any slight horn character - at least to my ears. I've played with a variety of amps, depending on how much power I want.
So here's the relevant info: I had done a couple of quick tries in the past of leaving the mids disconnected and crossing the woofer set with the TAD only. This thread motivated me to give it a little more effort. So I tried a variety of crossover points from 900Hz to 3.5kHz, and various slopes, all digital and mostly 48dB, but some steeper.
I should also note that the speakers are about 1.5M from the rear wall. I have them toed in to cross slightly in front of the center listening position. I had previously taken the rear cover off the TAD's and replaced them with a couple of layers of medium heavy cloth (to attenuate the upper end a bit). This "dipole" arrangement gave a noticable increase in the depth of the image and an increase in the sense of space.
The differences between the various crossovers were fairly subtle at the center listening position. At a crossover point above about 1200kHz the highs and image softened some when listening off center. Tonally, things were fine in all cases. However, the image quality was still a step better when using the midranges as described in my Unity thread.
Now, a couple of caveats: Limited testing, one set of ears, so weigh accordingly. Also, I know the digital filter approach is not what many want. I too, will probably work my way toward a combination of passive line and passive speaker crossovers, at least on the upper end. Will probably stay with active on the lower end. The upside of the DEQX is that it allows one to try many different combinations quickly, and it's easier (though not as flexible) as the full PC approach as exemplified by Shinobiwan. I think too, though I haven't done much testing, that the time alignment allows a very clear presentation.
The Unity is essentially a single point source, multiple driver arrangement. The improved image quality gained by the lower crossover to the horn, may be attributable to having the mid and upper frequencies closer in space than they would be with a large widerange crossed to a tweeter. So, my take on this is that Lynns coaxial approach, if good integration can be had between horn and widerange, might be the way to go for systems where full scale dynamics and an effective image illusion are the goal.
I'm picking up some smaller widerange alnico's and I'm going to try those with a tweeter as an alternative to the horn. It'll be interesting to see how that sounds.
Sheldon
I've followed this thread with great interest. I'll toss in one data point, if I may. My current system is shown here: http://www.diyaudio.com/forums/showthread.php?s=&threadid=69906&highlight="unity+horn" The crossover arrangement is described in the last couple of posts on the second page. I have filled the horns with open cell foam, per Earl Geddes and that pretty much eliminated any slight horn character - at least to my ears. I've played with a variety of amps, depending on how much power I want.
So here's the relevant info: I had done a couple of quick tries in the past of leaving the mids disconnected and crossing the woofer set with the TAD only. This thread motivated me to give it a little more effort. So I tried a variety of crossover points from 900Hz to 3.5kHz, and various slopes, all digital and mostly 48dB, but some steeper.
I should also note that the speakers are about 1.5M from the rear wall. I have them toed in to cross slightly in front of the center listening position. I had previously taken the rear cover off the TAD's and replaced them with a couple of layers of medium heavy cloth (to attenuate the upper end a bit). This "dipole" arrangement gave a noticable increase in the depth of the image and an increase in the sense of space.
The differences between the various crossovers were fairly subtle at the center listening position. At a crossover point above about 1200kHz the highs and image softened some when listening off center. Tonally, things were fine in all cases. However, the image quality was still a step better when using the midranges as described in my Unity thread.
Now, a couple of caveats: Limited testing, one set of ears, so weigh accordingly. Also, I know the digital filter approach is not what many want. I too, will probably work my way toward a combination of passive line and passive speaker crossovers, at least on the upper end. Will probably stay with active on the lower end. The upside of the DEQX is that it allows one to try many different combinations quickly, and it's easier (though not as flexible) as the full PC approach as exemplified by Shinobiwan. I think too, though I haven't done much testing, that the time alignment allows a very clear presentation.
The Unity is essentially a single point source, multiple driver arrangement. The improved image quality gained by the lower crossover to the horn, may be attributable to having the mid and upper frequencies closer in space than they would be with a large widerange crossed to a tweeter. So, my take on this is that Lynns coaxial approach, if good integration can be had between horn and widerange, might be the way to go for systems where full scale dynamics and an effective image illusion are the goal.
I'm picking up some smaller widerange alnico's and I'm going to try those with a tweeter as an alternative to the horn. It'll be interesting to see how that sounds.
Sheldon
Beaming, and RAAL
With the implementation of such a large driver for the midrange, how does one avoid beaming at higher frequencies? ie, when the frequency propagated is smaller in wavelength than the driver diameter.
I'm also interested in anyone's hands-on experience with the RAAL product.
Thanks in advance,
Chris
With the implementation of such a large driver for the midrange, how does one avoid beaming at higher frequencies? ie, when the frequency propagated is smaller in wavelength than the driver diameter.
I'm also interested in anyone's hands-on experience with the RAAL product.
Thanks in advance,
Chris
