The best of both worlds?
jeff mai wrote
“It is also possible to mount the horns on a baffle with no rear chamber. In this case there is no delayed energy release.”
If you do that, don’t you lose the efficiency benefits?
The Shearer horns it seems didn’t, can anyone explain why?
Maybe their open back (*like a dipole*) benefited the sound.
Jeff If you build straight horns, would they be open backed?
Any other open back horn experience?
jeff mai wrote
“It is also possible to mount the horns on a baffle with no rear chamber. In this case there is no delayed energy release.”
If you do that, don’t you lose the efficiency benefits?
The Shearer horns it seems didn’t, can anyone explain why?
Maybe their open back (*like a dipole*) benefited the sound.
Jeff If you build straight horns, would they be open backed?
Any other open back horn experience?
It would depend on the interaction of the driver/horn specs, but I suspect what you'd lose in most applications would be flat response on the low end. You'd also be controlling the diaphragm with the suspension compliance instead of the enclosed air spring, which IMO is generally a step in the less linear direction. Of course, YMMV.
Perhaps it could be a worthy tradeoff to lose the rear-chamber resonances. Magnetar seems happy with it in his system.
Re: The best of both worlds?
I have done this with poor to soso results- The back chamber is there for a reason. Without a properly sized sealed back chamber the response of the horn suffers. The chamber increases the Q of the system and is called reactance annulling giving more output in a certain range, an open (vented) chamber does this too but not as effective (but can extend the response down a bit) and no chamber at the back does do nothing but could be the most worse case for introducing phase problems. Others claim it can sound better because of the "no box" is the best box claims -- not true, the problem is they just haven't built a correct back chamber yet.
rick57 said:jeff mai wrote
“It is also possible to mount the horns on a baffle with no rear chamber. In this case there is no delayed energy release.”
If you do that, don’t you lose the efficiency benefits?
The Shearer horns it seems didn’t, can anyone explain why?
Maybe their open back (*like a dipole*) benefited the sound.
Jeff If you build straight horns, would they be open backed?
Any other open back horn experience?
I have done this with poor to soso results- The back chamber is there for a reason. Without a properly sized sealed back chamber the response of the horn suffers. The chamber increases the Q of the system and is called reactance annulling giving more output in a certain range, an open (vented) chamber does this too but not as effective (but can extend the response down a bit) and no chamber at the back does do nothing but could be the most worse case for introducing phase problems. Others claim it can sound better because of the "no box" is the best box claims -- not true, the problem is they just haven't built a correct back chamber yet.
Bill F. said:
Drivers made for horns don't rely on an air spring for linearity. If you use a driver that needs this air spring in a horn, you're using the wrong driver. A horn driver should have extremely low Qts.
Anyway, if this is a valid criticism it would apply to dipoles too wouldn't it? There is certainly no air spring in a dipole.
Returning to this graphic:
A second look at this primarily indicates to me that the exponential horn has lower HF bandwidth than the dipole, which is an expected result. That's the only thing the slower rise time means, anyway, yes?
Finally, I'd like to add that if you allow me to augment the bass horns with a non-horn bottom octave as you have suggested for the dipoles, lots of the horn's problems disappear, too. A free-standing, true 50Hz horn is manageable in a large room. You'd likely require 16 woofers / channel (8 dipole pairs) to keep up with a single pair of the horns.
paulspencer said:
A second look at this primarily indicates to me that the exponential horn has lower HF bandwidth than the dipole, which is an expected result. That's the only thing the slower rise time means, anyway, yes?
Finally, I'd like to add that if you allow me to augment the bass horns with a non-horn bottom octave as you have suggested for the dipoles, lots of the horn's problems disappear, too. A free-standing, true 50Hz horn is manageable in a large room. You'd likely require 16 woofers / channel (8 dipole pairs) to keep up with a single pair of the horns.
Re: Re: The best of both worlds?
I suspect that the back chamber is a trade-off; having it theoretically improves some things at the expense of other things. What actually sounds better in practice can only be determined by building the thing and listening to it.
This is where I value your opinions and experience. While everyone else is talking about it, you are already building it. In the end, I believe that the desire to understand things theoretically and make decisions accordingly is sometimes an obstacle to achieving great sounding hi-fi. Some things that are huge compromises, theoretically speaking, actually sound fantastic. Many people dismiss these on paper when they may actually prefer them to technically superior approaches.
Anyway, I never sealed up the back chambers of the Shearer horns, so I don't know which is better. I do know that my pair were *designed* to be open backed and that Harry F Olson was a moderately clever fellow.
I suspect that while there may have been trade offs involved in the decision they were open backed for a reason.
Magnetar said:
I suspect that the back chamber is a trade-off; having it theoretically improves some things at the expense of other things. What actually sounds better in practice can only be determined by building the thing and listening to it.
This is where I value your opinions and experience. While everyone else is talking about it, you are already building it. In the end, I believe that the desire to understand things theoretically and make decisions accordingly is sometimes an obstacle to achieving great sounding hi-fi. Some things that are huge compromises, theoretically speaking, actually sound fantastic. Many people dismiss these on paper when they may actually prefer them to technically superior approaches.
Anyway, I never sealed up the back chambers of the Shearer horns, so I don't know which is better. I do know that my pair were *designed* to be open backed and that Harry F Olson was a moderately clever fellow.
I suspect that while there may have been trade offs involved in the decision they were open backed for a reason.
Konnichiwa,
I'll keep this short. I don't have the time to keep this tit for tat going and to refute all and sundary inconsitencies and inaccurate claims, just a few really juicy ones.
If your subs are not monopoles, what is the point of the rigid wall? For a directional Horn it matters zip what is behind it!.
Given your arrangement in the vertical plane only to 60Hz, in the horizontal plane I'd expect any pattern control to cease at much higher a frequency as what you have very much resembles a diffraction horn, with controlled vertical directivity and wide horizontal one. This will impact on the room mode excitation, but at least the horns are well out of corners and close to sidewalls making this less of a problem in practice.
My dipoles need no EQ and are in the horizontal plane most likely superior with regards to directivity.
That is worth something, I'm at 94db/2.83V/1m at around 70Hz. I never suggested that horns did not have specific applications (very high SPL's are one) and that they cannot be sucessfully deployed. I did argue that for a given physical size in most normal size rooms the dipole or unipole arrangement will be favourable, something I continue to stand by.
Hmm, if I build a True W Dipole woofer aimed at covering 50Hz - 150Hz with the same width and hight of your horn I would not find it exceedingly difficult to match or at least closely approach the 108db/W/m @ 70Hz figure and to to provide superior directivity control in the horizontal plane, at the modest expedient of using a largish number of 10" or 12" Drivers.
At a guess I'd think I can fit an 12 Driver W Dipole into the kind of (fronatl surface) space of your horns. With 12 Drivers I get around 10db gain on the single driver, so a driver with 98db/2.83V/1m @ 70Hz is required, not an exceedingly difficult. Even using the Eminence Delta 12LF I should get around 102..103db/1W/1m at 70Hz and I would argue with superior directivity and transient response.
I think what this whole disagreement is about is your complete dismassal of any merit of a well implemented dipole system as offering a possible solution and instead insisting that dipoles are useless. As I pointed out before, horns and dipoles have their uses and applications.....
Hmmm. Yet the following Document ("RECOMMENDED PRACTICE SSF – 01.1- E-2002 Listening Conditions and Reproduction Arrangements For Multichannel Stereophony") explicitly specifies a tolerance field for the difference of the reverb time compared to that at 200Hz which is quite stringent and implies full control of room modes and the rise at low frequencies down to 125Hz with a rise by no more than 200mS towards 63Hz based on the much older EBU recommendations with a flat reverbtime to 200hz and no more 300mS rise to 63Hz.
Source document here:
http://www.tonmeister.de/foren/surround/texte/SSF_01_1_E_2002_v2a.PDF
Clearly, those who set the standards for Sound Studios in Europe for Radio & TV and who recommend practice in general for both home and studio conditions do not agree with the position you promote ("RT-60 measurements in small room acoustics below 200Hz have little significance as they are flawed by the energy build-up of room modes. ") and I would argue that they are in a better position to make such judgements.
See my response yo your response.
In what objective parameters?
I appreciate your comment that you felt it "sounded better", but if the 8 pcs of 15" JBL woofers where not even close, in what parameters?
Sayonara
I'll keep this short. I don't have the time to keep this tit for tat going and to refute all and sundary inconsitencies and inaccurate claims, just a few really juicy ones.
Magnetar said:
If your subs are not monopoles, what is the point of the rigid wall? For a directional Horn it matters zip what is behind it!.
Magnetar said:
Given your arrangement in the vertical plane only to 60Hz, in the horizontal plane I'd expect any pattern control to cease at much higher a frequency as what you have very much resembles a diffraction horn, with controlled vertical directivity and wide horizontal one. This will impact on the room mode excitation, but at least the horns are well out of corners and close to sidewalls making this less of a problem in practice.
Magnetar said:
My dipoles need no EQ and are in the horizontal plane most likely superior with regards to directivity.
Magnetar said:
That is worth something, I'm at 94db/2.83V/1m at around 70Hz. I never suggested that horns did not have specific applications (very high SPL's are one) and that they cannot be sucessfully deployed. I did argue that for a given physical size in most normal size rooms the dipole or unipole arrangement will be favourable, something I continue to stand by.
Magnetar said:
Hmm, if I build a True W Dipole woofer aimed at covering 50Hz - 150Hz with the same width and hight of your horn I would not find it exceedingly difficult to match or at least closely approach the 108db/W/m @ 70Hz figure and to to provide superior directivity control in the horizontal plane, at the modest expedient of using a largish number of 10" or 12" Drivers.
At a guess I'd think I can fit an 12 Driver W Dipole into the kind of (fronatl surface) space of your horns. With 12 Drivers I get around 10db gain on the single driver, so a driver with 98db/2.83V/1m @ 70Hz is required, not an exceedingly difficult. Even using the Eminence Delta 12LF I should get around 102..103db/1W/1m at 70Hz and I would argue with superior directivity and transient response.
I think what this whole disagreement is about is your complete dismassal of any merit of a well implemented dipole system as offering a possible solution and instead insisting that dipoles are useless. As I pointed out before, horns and dipoles have their uses and applications.....
Magnetar said:
Hmmm. Yet the following Document ("RECOMMENDED PRACTICE SSF – 01.1- E-2002 Listening Conditions and Reproduction Arrangements For Multichannel Stereophony") explicitly specifies a tolerance field for the difference of the reverb time compared to that at 200Hz which is quite stringent and implies full control of room modes and the rise at low frequencies down to 125Hz with a rise by no more than 200mS towards 63Hz based on the much older EBU recommendations with a flat reverbtime to 200hz and no more 300mS rise to 63Hz.
An externally hosted image should be here but it was not working when we last tested it.
Source document here:
http://www.tonmeister.de/foren/surround/texte/SSF_01_1_E_2002_v2a.PDF
Clearly, those who set the standards for Sound Studios in Europe for Radio & TV and who recommend practice in general for both home and studio conditions do not agree with the position you promote ("RT-60 measurements in small room acoustics below 200Hz have little significance as they are flawed by the energy build-up of room modes. ") and I would argue that they are in a better position to make such judgements.
Magnetar said:
See my response yo your response.
Magnetar said:
In what objective parameters?
I appreciate your comment that you felt it "sounded better", but if the 8 pcs of 15" JBL woofers where not even close, in what parameters?
Sayonara
Originally posted by Kuei Yang Wang [/i]
I'll keep this short. I don't have the time to keep this tit for tat going and to refute all and sundary inconsitencies and inaccurate claims, just a few really juicy ones.
I can see why - You are talking about your claims here aren't you?
If your subs are not monopoles, what is the point of the rigid wall? For a directional Horn it matters zip what is behind it!.
The rigid front and side walls are part of the horn. You know that - the entire lower half of my front wall is the horn mouth for the subhorn.
Below is your monopole bass system. You use that little box behind the baffle right? It is not directional in the bass (classic monopole bass) where the horns I use are very much so. Now if you measure my horns at zero, 90, 120, 180 degrees (the last three require you to actually leave my room and do outside and the last one requires you digging a hole next to my house) you will find it measures quite differently in respect to radiation (any surely alot of other things) than that little "monopole subwoofer" you have in your system :
Given your arrangement in the vertical plane only to 60Hz, in the horizontal plane I'd expect any pattern control to cease at much higher a frequency as what you have very much resembles a diffraction horn, with controlled vertical directivity and wide horizontal one. This will impact on the room mode excitation, but at least the horns are well out of corners and close to sidewalls making this less of a problem in practice.
In practice, it actually sounds better when the midbass horns are to the inside of spherical satellites. If you look a little closer and think a little harder you will find you are incorrect and the horns have wider radiation in the vertical plane than the horizontal plane! We aren't talking about a ribbon tweeter here are we?
My dipoles need no EQ and are in the horizontal plane most likely superior with regards to directivity
They need eq if you want bass drom them - remember you have to resort to non-directional monopole bass because your dipoles don't cut it. I find your statements regarding the horizontal radiation of my midbass horns to be 100 percent false.
That is worth something, I'm at 94db/2.83V/1m at around 70Hz. I never suggested that horns did not have specific applications (very high SPL's are one) and that they cannot be sucessfully deployed. I did argue that for a given physical size in most normal size rooms the dipole or unipole arrangement will be favourable, something I continue to stand by.
Why? I can acheive as good or better pattern control as you can with my bass horns plus more efficiently put bass in the room where I want it.
Hmm, if I build a True W Dipole woofer aimed at covering 50Hz - 150Hz with the same width and hight of your horn I would not find it exceedingly difficult to match or at least closely approach the 108db/W/m @ 70Hz figure and to to provide superior directivity control in the horizontal plane, at the modest expedient of using a largish number of 10" or 12" Drivers.
I'd like to see that one! IME my single 15 will be easier to drive, have better controlled directivity ( there ain't no backwave for one) nad sound better than what you propose.
At a guess I'd think I can fit an 12 Driver W Dipole into the kind of (fronatl surface) space of your horns. With 12 Drivers I get around 10db gain on the single driver, so a driver with 98db/2.83V/1m @ 70Hz is required, not an exceedingly difficult. Even using the Eminence Delta 12LF I should get around 102..103db/1W/1m at 70Hz and I would argue with superior directivity and transient response.
You can argue that all you want but you will be incorrect.
I think what this whole disagreement is about is your complete dismassal of any merit of a well implemented dipole system as offering a possible solution and instead insisting that dipoles are useless. As I pointed out before, horns and dipoles have their uses and applications.....
Sure you can use anything you want. I prefer to use horns. They offer everything a dipole offers but more. I do like the sound of some open baffle mids over some direct radiators. As most people would agree there are good and bad examples of all types of speaker loading schemes.
Please show me where I completely dismiss a dipole as being a solotion. You made that up.
Hmmm. Yet the following Document ("RECOMMENDED PRACTICE SSF – 01.1- E-2002 Listening Conditions and Reproduction Arrangements For Multichannel Stereophony") explicitly specifies a tolerance field for the difference of the reverb time compared to that at 200Hz which is quite stringent and implies full control of room modes and the rise at low frequencies down to 125Hz with a rise by no more than 200mS towards 63Hz based on the much older EBU recommendations with a flat reverbtime to 200hz and no more 300mS rise to 63Hz.
Source document here:
http://www.tonmeister.de/foren/surround/texte/SSF_01_1_E_2002_v2a.PDF
Clearly, those who set the standards for Sound Studios in Europe for Radio & TV and who recommend practice in general for both home and studio conditions do not agree with the position you promote ("RT-60 measurements in small room acoustics below 200Hz have little significance as they are flawed by the energy build-up of room modes. ") and I would argue that they are in a better position to make such judgements.
1) Explain to me how you measure this in your room (below 200 cycles) and post what you measured the RT60 to be at 20, 40, 80, and 160 cycles.
2) I read the document and find no mention of how they ACCURATELY measure this reverb below 200 cycles --
Seems this document is a fantasy document. In the bass in a small room this is modal reflections - not reverb.
In what objective parameters?
I appreciate your comment that you felt it "sounded better", but if the 8 pcs of 15" JBL woofers where not even close, in what parameters?
Higher dynamic range, more linear, easier to drive, more sensitive.
PS --I'd like to compare the eight fifteens with your monopole sub --
Sayonara [/B][/QUOTE]
I'll keep this short. I don't have the time to keep this tit for tat going and to refute all and sundary inconsitencies and inaccurate claims, just a few really juicy ones.
I can see why - You are talking about your claims here aren't you?
If your subs are not monopoles, what is the point of the rigid wall? For a directional Horn it matters zip what is behind it!.
The rigid front and side walls are part of the horn. You know that - the entire lower half of my front wall is the horn mouth for the subhorn.
Below is your monopole bass system. You use that little box behind the baffle right? It is not directional in the bass (classic monopole bass) where the horns I use are very much so. Now if you measure my horns at zero, 90, 120, 180 degrees (the last three require you to actually leave my room and do outside and the last one requires you digging a hole next to my house) you will find it measures quite differently in respect to radiation (any surely alot of other things) than that little "monopole subwoofer" you have in your system :
An externally hosted image should be here but it was not working when we last tested it.
Given your arrangement in the vertical plane only to 60Hz, in the horizontal plane I'd expect any pattern control to cease at much higher a frequency as what you have very much resembles a diffraction horn, with controlled vertical directivity and wide horizontal one. This will impact on the room mode excitation, but at least the horns are well out of corners and close to sidewalls making this less of a problem in practice.
In practice, it actually sounds better when the midbass horns are to the inside of spherical satellites. If you look a little closer and think a little harder you will find you are incorrect and the horns have wider radiation in the vertical plane than the horizontal plane! We aren't talking about a ribbon tweeter here are we?
My dipoles need no EQ and are in the horizontal plane most likely superior with regards to directivity
They need eq if you want bass drom them - remember you have to resort to non-directional monopole bass because your dipoles don't cut it. I find your statements regarding the horizontal radiation of my midbass horns to be 100 percent false.
That is worth something, I'm at 94db/2.83V/1m at around 70Hz. I never suggested that horns did not have specific applications (very high SPL's are one) and that they cannot be sucessfully deployed. I did argue that for a given physical size in most normal size rooms the dipole or unipole arrangement will be favourable, something I continue to stand by.
Why? I can acheive as good or better pattern control as you can with my bass horns plus more efficiently put bass in the room where I want it.
Hmm, if I build a True W Dipole woofer aimed at covering 50Hz - 150Hz with the same width and hight of your horn I would not find it exceedingly difficult to match or at least closely approach the 108db/W/m @ 70Hz figure and to to provide superior directivity control in the horizontal plane, at the modest expedient of using a largish number of 10" or 12" Drivers.
I'd like to see that one! IME my single 15 will be easier to drive, have better controlled directivity ( there ain't no backwave for one) nad sound better than what you propose.
At a guess I'd think I can fit an 12 Driver W Dipole into the kind of (fronatl surface) space of your horns. With 12 Drivers I get around 10db gain on the single driver, so a driver with 98db/2.83V/1m @ 70Hz is required, not an exceedingly difficult. Even using the Eminence Delta 12LF I should get around 102..103db/1W/1m at 70Hz and I would argue with superior directivity and transient response.
You can argue that all you want but you will be incorrect.
I think what this whole disagreement is about is your complete dismassal of any merit of a well implemented dipole system as offering a possible solution and instead insisting that dipoles are useless. As I pointed out before, horns and dipoles have their uses and applications.....
Sure you can use anything you want. I prefer to use horns. They offer everything a dipole offers but more. I do like the sound of some open baffle mids over some direct radiators. As most people would agree there are good and bad examples of all types of speaker loading schemes.
Please show me where I completely dismiss a dipole as being a solotion. You made that up.
Hmmm. Yet the following Document ("RECOMMENDED PRACTICE SSF – 01.1- E-2002 Listening Conditions and Reproduction Arrangements For Multichannel Stereophony") explicitly specifies a tolerance field for the difference of the reverb time compared to that at 200Hz which is quite stringent and implies full control of room modes and the rise at low frequencies down to 125Hz with a rise by no more than 200mS towards 63Hz based on the much older EBU recommendations with a flat reverbtime to 200hz and no more 300mS rise to 63Hz.
An externally hosted image should be here but it was not working when we last tested it.
Source document here:
http://www.tonmeister.de/foren/surround/texte/SSF_01_1_E_2002_v2a.PDF
Clearly, those who set the standards for Sound Studios in Europe for Radio & TV and who recommend practice in general for both home and studio conditions do not agree with the position you promote ("RT-60 measurements in small room acoustics below 200Hz have little significance as they are flawed by the energy build-up of room modes. ") and I would argue that they are in a better position to make such judgements.
1) Explain to me how you measure this in your room (below 200 cycles) and post what you measured the RT60 to be at 20, 40, 80, and 160 cycles.
2) I read the document and find no mention of how they ACCURATELY measure this reverb below 200 cycles --
Seems this document is a fantasy document. In the bass in a small room this is modal reflections - not reverb.
In what objective parameters?
I appreciate your comment that you felt it "sounded better", but if the 8 pcs of 15" JBL woofers where not even close, in what parameters?
Higher dynamic range, more linear, easier to drive, more sensitive.
PS --I'd like to compare the eight fifteens with your monopole sub --
Sayonara [/B][/QUOTE]
Re: Re: Re: The best of both worlds?
Olson surely knew what he doing and has great respect but the horn could be improved -- can't anything in hiifi? What's perfect?
Olson surely knew what he doing and has great respect but the horn could be improved -- can't anything in hiifi? What's perfect?
jeff mai said:
I suspect that the back chamber is a trade-off; having it theoretically improves some things at the expense of other things. What actually sounds better in practice can only be determined by building the thing and listening to it.
This is where I value your opinions and experience. While everyone else is talking about it, you are already building it. In the end, I believe that the desire to understand things theoretically and make decisions accordingly is sometimes an obstacle to achieving great sounding hi-fi. Some things that are huge compromises, theoretically speaking, actually sound fantastic. Many people dismiss these on paper when they may actually prefer them to technically superior approaches.
Anyway, I never sealed up the back chambers of the Shearer horns, so I don't know which is better. I do know that my pair were *designed* to be open backed and that Harry F Olson was a moderately clever fellow.
Re: Re: Re: Re: The best of both worlds?
Surely they may be improved by sealing the back. Or they may be impaired. Or they may be improved in some parameters and impaired in others. Or they may be improved in certain rooms or set-ups and impaired in others. Or they may be improved in the opinion of some and impaired in the opinion of others. Or they may be neither improved or impaired. Or they may be both improved and impaired...
Magnetar said:
Surely they may be improved by sealing the back. Or they may be impaired. Or they may be improved in some parameters and impaired in others. Or they may be improved in certain rooms or set-ups and impaired in others. Or they may be improved in the opinion of some and impaired in the opinion of others. Or they may be neither improved or impaired. Or they may be both improved and impaired...
Konnichiwa,
No claims, facts.
Sorry, but I take issue here. I for one do not support the davertising claims that the "walls form the horn mouth" to justify the manufacture and sale of foreshortened horns. I clearly made that point earlier in the thread.
If the walls supply the "waveguide" than at the relevant frequencies your horn has ceased to be a horn and become (more or less) omnidirectional.
It is not intended to be directional.
In free or halve space? Then you don't need any walls to supply the "hornmouth".
The Sub in my system is aimed purely at filling in the lowest octave and to match only the SPL of the main system (which due to the limited cone surface is not that high).
Well, the retention of directivity control with frequency of a given horn (especially the kind you use) is directly proportional to the main dimensions. Hence a horn that is narrow but tall has good directivity control at fairly low frequencies in the vertical plane but poor directivity control at fairly low frequencies in the horizontal plane.
The kind of design you use is (was?) quite common in PA stacks and attained in it's normal use (lying down compared to your "standing up" application) significant vertical pattern control at low frequencies (near the horn cutoff) only with several units stacked (which is the intended use). As you have changed the orientation your horns will experience a material shifting in directivity with frequency, though the fairly narrowband use will keep that to a minimum.
At a guess I'd expect the hight (in your arrangement width) of the Horn to be around 0.5m with an attendant loss of directivity control (and progressive reversion to omnidirectional radiation in the relevant plane) at around 170Hz.
No, we ARE however talking about the directivity control behaviour of a tall and narrow sound source, of which slot radiators and ribbons are a special case. The same principles apply, as you will find on perusal of the relevant literature.
They need eq if you want bass drom them - remember you have to resort to non-directional monopole bass because your dipoles don't cut it.
[/B][/QUOTE]
I use Subwoofers because when designing my Dipoles I made a concious desicion that I would limit the LF extension (in room) to -6db @ 50Hz and the Drivers used have a Fs of 50Hz, so no matter what sort of dipole or baffle you place them in there will ALWAYS be a requirement for a Subwoofer to cover the lowest octave.
So the addition of a subwoofer (I personally at home use a single dual 12" "URPS" type unit) is part of the design brief. At the Show where the picture was taken we used the REL Quake's (one per channel) for good looks and commercial availability. The system did extremely well I'd like to add in a rather large room top to bottom, much better than I had expected.
You may find them whatever you like. I merely observe the pertinent facts, you do not have to LIKE them or find them anything. Facts remain ojective regardless of how we percieve them.
Simply based on the inability of your horn to provide directivity control at low frequencies in one plane (which in your case is the horizontal one) I think we can safely disregard the directivity argument. As for ease of drive, this would remain to be investigated with a real system.
To your PERSONAL TASTE.
Actually, with a long enough window ETF will display any number of the various RTXX settings. I do not own the software, so measurements where done by a (Audio)Friend.
As he had done many he suspected measurement anomalies when a dipole speaker failed to show the usual behaviour with RT60. Several re-measuremnets later and wirh more dipole systems measured he concluded that the fairly flat RT60 (and shorter) is a byproduct of the dipoles operation, something I find to hold both practical and theoretical. In order to measure my current system I'll have invite him around, which shall be interresting anyway.
Beacuse you measure it the same way as above 200Hz. Room modes do not make reverb time measurements inaccurate, they simply increase the reverb time and this is a rather accurate statement and observation of what they do. This was the point of my argument BTW.
I take it that you would wish to inform the AES, EBU and IRT of the errors of their ways? Go ahead. The Document comes from the German "Verband Deutscher Tonmeister" (Society of German Sound Engineers), for all intent and purpose the German equivalent of (USA) AES. The VDT is generally a highly respected professional organisation for Sound Engineers with a long standing and extensive record on acosutical research covering recording, transmission and reproduction of sound.
I tend to be at odds usually especially with the AES/JAES about a number of issues and their general approach to "fringe" issues, however there is a lot of solid, well backed research found within the AES and other similar organisations and I may be forgiven for considering the results of such research to be of more weight than those of individuals/companies who usually have commercial interests in promoting views that contradict the extant research.
Neither myself nor the VDT claim that the referenced document is a complete and comprehensive specification, it merely sets out minimum standards, whith which I happen to agree in principle.
Sayonara
Magnetar said:I can see why - You are talking about your claims here aren't you?
No claims, facts.
Magnetar said:
Sorry, but I take issue here. I for one do not support the davertising claims that the "walls form the horn mouth" to justify the manufacture and sale of foreshortened horns. I clearly made that point earlier in the thread.
If the walls supply the "waveguide" than at the relevant frequencies your horn has ceased to be a horn and become (more or less) omnidirectional.
Magnetar said:
It is not intended to be directional.
Magnetar said:
In free or halve space? Then you don't need any walls to supply the "hornmouth".
Magnetar said:
The Sub in my system is aimed purely at filling in the lowest octave and to match only the SPL of the main system (which due to the limited cone surface is not that high).
Magnetar said:
Well, the retention of directivity control with frequency of a given horn (especially the kind you use) is directly proportional to the main dimensions. Hence a horn that is narrow but tall has good directivity control at fairly low frequencies in the vertical plane but poor directivity control at fairly low frequencies in the horizontal plane.
The kind of design you use is (was?) quite common in PA stacks and attained in it's normal use (lying down compared to your "standing up" application) significant vertical pattern control at low frequencies (near the horn cutoff) only with several units stacked (which is the intended use). As you have changed the orientation your horns will experience a material shifting in directivity with frequency, though the fairly narrowband use will keep that to a minimum.
At a guess I'd expect the hight (in your arrangement width) of the Horn to be around 0.5m with an attendant loss of directivity control (and progressive reversion to omnidirectional radiation in the relevant plane) at around 170Hz.
Magnetar said:
No, we ARE however talking about the directivity control behaviour of a tall and narrow sound source, of which slot radiators and ribbons are a special case. The same principles apply, as you will find on perusal of the relevant literature.
Kuei Yang Wang said:
They need eq if you want bass drom them - remember you have to resort to non-directional monopole bass because your dipoles don't cut it.
[/B][/QUOTE]
I use Subwoofers because when designing my Dipoles I made a concious desicion that I would limit the LF extension (in room) to -6db @ 50Hz and the Drivers used have a Fs of 50Hz, so no matter what sort of dipole or baffle you place them in there will ALWAYS be a requirement for a Subwoofer to cover the lowest octave.
So the addition of a subwoofer (I personally at home use a single dual 12" "URPS" type unit) is part of the design brief. At the Show where the picture was taken we used the REL Quake's (one per channel) for good looks and commercial availability. The system did extremely well I'd like to add in a rather large room top to bottom, much better than I had expected.
Magnetar said:
You may find them whatever you like. I merely observe the pertinent facts, you do not have to LIKE them or find them anything. Facts remain ojective regardless of how we percieve them.
Magnetar said:
Simply based on the inability of your horn to provide directivity control at low frequencies in one plane (which in your case is the horizontal one) I think we can safely disregard the directivity argument. As for ease of drive, this would remain to be investigated with a real system.
Magnetar said:
To your PERSONAL TASTE.
Magnetar said:
Actually, with a long enough window ETF will display any number of the various RTXX settings. I do not own the software, so measurements where done by a (Audio)Friend.
As he had done many he suspected measurement anomalies when a dipole speaker failed to show the usual behaviour with RT60. Several re-measuremnets later and wirh more dipole systems measured he concluded that the fairly flat RT60 (and shorter) is a byproduct of the dipoles operation, something I find to hold both practical and theoretical. In order to measure my current system I'll have invite him around, which shall be interresting anyway.
Magnetar said:
Beacuse you measure it the same way as above 200Hz. Room modes do not make reverb time measurements inaccurate, they simply increase the reverb time and this is a rather accurate statement and observation of what they do. This was the point of my argument BTW.
Magnetar said:
I take it that you would wish to inform the AES, EBU and IRT of the errors of their ways? Go ahead. The Document comes from the German "Verband Deutscher Tonmeister" (Society of German Sound Engineers), for all intent and purpose the German equivalent of (USA) AES. The VDT is generally a highly respected professional organisation for Sound Engineers with a long standing and extensive record on acosutical research covering recording, transmission and reproduction of sound.
I tend to be at odds usually especially with the AES/JAES about a number of issues and their general approach to "fringe" issues, however there is a lot of solid, well backed research found within the AES and other similar organisations and I may be forgiven for considering the results of such research to be of more weight than those of individuals/companies who usually have commercial interests in promoting views that contradict the extant research.
Neither myself nor the VDT claim that the referenced document is a complete and comprehensive specification, it merely sets out minimum standards, whith which I happen to agree in principle.
Sayonara
Magnetar,
I suggest you google up the words "general semantics" and "E-prime" and have a read about it. Using the hereby acquired techniques, you could then try to reword your statements without using the verb "to be" in any of its forms. This may help transforming your statements from sounding like claimed facts towards sounding like genuine, legitimate personal experience. As a welcome by-product, the above procedure may also make your posts much more palatable and enjoyable.
KYW,
I am surprised! You can at times come across as quite opinionated (no offense intended, I find your posts informative and often hilarious), but in this thread you really try to stay on the ground no matter how far Magnetar pushes it into hyperbole.
I couldn't agree more.
I suggest you google up the words "general semantics" and "E-prime" and have a read about it. Using the hereby acquired techniques, you could then try to reword your statements without using the verb "to be" in any of its forms. This may help transforming your statements from sounding like claimed facts towards sounding like genuine, legitimate personal experience. As a welcome by-product, the above procedure may also make your posts much more palatable and enjoyable.
KYW,
I am surprised! You can at times come across as quite opinionated (no offense intended, I find your posts informative and often hilarious), but in this thread you really try to stay on the ground no matter how far Magnetar pushes it into hyperbole.
I couldn't agree more.
MBK said:
1) I'm not here to entertain you with "palatable and enjoyable" posts. If you don't like what I say or how I say it then simply don't read my posts.
2) What does this have to do with the subject of this thread? If you have anything to dispute about the claims (you use the worf hyperbole) I've made please feel free to prove me wrong - if not please keep your mouth shut.
3) Show me where I "complete dismassal of any merit of a well implemented dipole system as offering a possible solution and instead insisting that dipoles are useless. "
Magnetar,
How would I find out about their content without reading them first?
So, do you purposely write your posts in order to be neither palatable nor enjoyable?
illustrates my case.
My case, in reply to:
is that all contributors would benefit if you could only present your experiences and claims in some sort of structured and non-offensive manner. This way we could all learn something, either from each other, or heavens forbid, we could find out something new by discussing the issue and raising new questions. And this structured, well documented and non offensive thingy is what I miss from your posts. Barring the aforementioned, your posts indeed reduce to entertainment of some sorts. Because in fact the bottom line of what I have learned from this thread is that you tried many dipoles and horns, that you have a lot of experience, but absent data, measurements, schematics, calculations, theoretical considerations, references, or any other kind of evidence, we all must conclude you like horns better but we don't really know how this came to be such or how to replicate your experience.
How would I find out about their content without reading them first?
So, do you purposely write your posts in order to be neither palatable nor enjoyable?
illustrates my case.
My case, in reply to:
is that all contributors would benefit if you could only present your experiences and claims in some sort of structured and non-offensive manner. This way we could all learn something, either from each other, or heavens forbid, we could find out something new by discussing the issue and raising new questions. And this structured, well documented and non offensive thingy is what I miss from your posts. Barring the aforementioned, your posts indeed reduce to entertainment of some sorts. Because in fact the bottom line of what I have learned from this thread is that you tried many dipoles and horns, that you have a lot of experience, but absent data, measurements, schematics, calculations, theoretical considerations, references, or any other kind of evidence, we all must conclude you like horns better but we don't really know how this came to be such or how to replicate your experience.
Konnichiwa,
To illustrate the point a bit more here a little piccie from the Datasheet for the EV HP1240 Horn.
http://www.electrovoice.com/electrovoice/EVfiles.nsf/lookup/HP1240EDS/$File/hp1240-eds.pdf
In this datasheet we see a horn with a Vertical size around 1/2 that of Horizontal. Correspondingly the beamwidth is controlled in the vertical plane to only around halve the wavelength (twice the frequency) to the horizontal.
An even more extreme example and more pertinent to the horn discussed is the JBL Diffraction Horn 2397.
http://www.jblpro.com/pub/obsolete/2397.pdf
In this datasheet we see a horn with a very narrow vertical dimension and a more or less exponential expansion in the horizontal plane, quite similar to Mag's Horns.
Here we observe practically NO directivity control in the vertical plane until the wavelength becomes large with respect to vertical dimension with a pretty resonable control on the horizontal directivity. Put the horn on edge and you have an extremely wide dispersion horizontally and very narrow vertical, as observable on all such structures.
I hope that clarifies the issues and illustrates WHY I assert that the horns employed by Mag have no horizontal directivity control whithin the range and in the orientation used by Mag.
Sayonara
Kuei Yang Wang said:
To illustrate the point a bit more here a little piccie from the Datasheet for the EV HP1240 Horn.
http://www.electrovoice.com/electrovoice/EVfiles.nsf/lookup/HP1240EDS/$File/hp1240-eds.pdf
In this datasheet we see a horn with a Vertical size around 1/2 that of Horizontal. Correspondingly the beamwidth is controlled in the vertical plane to only around halve the wavelength (twice the frequency) to the horizontal.
An externally hosted image should be here but it was not working when we last tested it.
An even more extreme example and more pertinent to the horn discussed is the JBL Diffraction Horn 2397.
http://www.jblpro.com/pub/obsolete/2397.pdf
In this datasheet we see a horn with a very narrow vertical dimension and a more or less exponential expansion in the horizontal plane, quite similar to Mag's Horns.
An externally hosted image should be here but it was not working when we last tested it.
Here we observe practically NO directivity control in the vertical plane until the wavelength becomes large with respect to vertical dimension with a pretty resonable control on the horizontal directivity. Put the horn on edge and you have an extremely wide dispersion horizontally and very narrow vertical, as observable on all such structures.
I hope that clarifies the issues and illustrates WHY I assert that the horns employed by Mag have no horizontal directivity control whithin the range and in the orientation used by Mag.
Sayonara
[Originally posted by Kuei Yang Wang [/i]
Konnichiwa,
Sorry, but I take issue here. I for one do not support the davertising claims that the "walls form the horn mouth" to justify the manufacture and sale of foreshortened horns. I clearly made that point earlier in the thread.
I do not sell horns. The walls DO in fact form the horn mouth. Again you are incorrect. AFA the sell of foreshortened bass horns, show me one that I can buy that is full sized.
If the walls supply the "waveguide" than at the relevant frequencies your horn has ceased to be a horn and become (more or less) omnidirectional.
False. As I said before the floor and walls form the "waveguide" and if horn was omni-directional it would have the same response to a full 360 degrees. It does not - therefore it is not a monopole. If you read what I wrote you would understand this without question and agree. Instead you'd rather use this non-arguement.
It is not intended to be directional.
That was my intention. How can this be disputed?
In free or halve space? Then you don't need any walls to supply the "hornmouth".
It is in 1/8th space.
The Sub in my system is aimed purely at filling in the lowest octave and to match only the SPL of the main system (which due to the limited cone surface is not that high).
I agree
Well, the retention of directivity control with frequency of a given horn (especially the kind you use) is directly proportional to the main dimensions. Hence a horn that is narrow but tall has good directivity control at fairly low frequencies in the vertical plane but poor directivity control at fairly low frequencies in the horizontal plane.
Of course this is true to an extent -- problem with your argument is the parallel vertical sidewalls do in fact form a waveguide and are in fact directional and there is in fact an alteration in the horizontal response beyond placing the driver on a flat plane such as your open baffle scheme.
The kind of design you use is (was?) quite common in PA stacks and attained in it's normal use (lying down compared to your "standing up" application) significant vertical pattern control at low frequencies (near the horn cutoff) only with several units stacked (which is the intended use). As you have changed the orientation your horns will experience a material shifting in directivity with frequency, though the fairly narrowband use will keep that to a minimum.
Yawn....
At a guess I'd expect the hight (in your arrangement width) of the Horn to be around 0.5m with an attendant loss of directivity control (and progressive reversion to omnidirectional radiation in the relevant plane) at around 170Hz.
That is a guess. It has much less output within it's operating range at 90, 120 and 180 degrees compared to on axis than a monopole omnidirectional loudspeaker.
No, we ARE however talking about the directivity control behaviour of a tall and narrow sound source, of which slot radiators and ribbons are a special case. The same principles apply, as you will find on perusal of the relevant literature.
A slot ribbon normally does not have a horn attached to it -- when it does the directivity is altered as it is with my mibass horns.
I use Subwoofers because when designing my Dipoles I made a concious desicion that I would limit the LF extension (in room) to -6db @ 50Hz and the Drivers used have a Fs of 50Hz, so no matter what sort of dipole or baffle you place them in there will ALWAYS be a requirement for a Subwoofer to cover the lowest octave.
So the addition of a subwoofer (I personally at home use a single dual 12" "URPS" type unit) is part of the design brief. At the Show where the picture was taken we used the REL Quake's (one per channel) for good looks and commercial availability. The system did extremely well I'd like to add in a rather large room top to bottom, much better than I had expected.
Yawn... I'm glad you like it! Did you sell any????????
You may find them whatever you like. I merely observe the pertinent facts, you do not have to LIKE them or find them anything. Facts remain ojective regardless of how we percieve them.
Double yawn......
Simply based on the inability of your horn to provide directivity control at low frequencies in one plane (which in your case is the horizontal one) I think we can safely disregard the directivity argument. As for ease of drive, this would remain to be investigated with a real system.
I have one here and have verified my facts. You on the other hand are guessing.
To your PERSONAL TASTE.
And to yours
Actually, with a long enough window ETF will display any number of the various RTXX settings. I do not own the software, so measurements where done by a (Audio)Friend.
As he had done many he suspected measurement anomalies when a dipole speaker failed to show the usual behaviour with RT60. Several re-measuremnets later and wirh more dipole systems measured he concluded that the fairly flat RT60 (and shorter) is a byproduct of the dipoles operation, something I find to hold both practical and theoretical. In order to measure my current system I'll have invite him around, which shall be interresting anyway.
Please do, then you can state some facts rather then guess!
Beacuse you measure it the same way as above 200Hz. Room modes do not make reverb time measurements inaccurate, they simply increase the reverb time and this is a rather accurate statement and observation of what they do. This was the point of my argument BTW.
This is false. There is no reverberent field so RT60 cannot be measured properly -- too much direct sound, rooms not big enough, room modal interferance, and interfarence between modes is a start.
I take it that you would wish to inform the AES, EBU and IRT of the errors of their ways? Go ahead. The Document comes from the German "Verband Deutscher Tonmeister" (Society of German Sound Engineers), for all intent and purpose the German equivalent of (USA) AES. The VDT is generally a highly respected professional organisation for Sound Engineers with a long standing and extensive record on acosutical research covering recording, transmission and reproduction of sound.
No, I don't care
I tend to be at odds usually especially with the AES/JAES about a number of issues and their general approach to "fringe" issues, however there is a lot of solid, well backed research found within the AES and other similar organisations and I may be forgiven for considering the results of such research to be of more weight than those of individuals/companies who usually have commercial interests in promoting views that contradict the extant research.
If you want I can find plenty of information at AES that proves RT60 is irrelavent to measure below 200 cycles in a small room.
Neither myself nor the VDT claim that the referenced document is a complete and comprehensive specification, it merely sets out minimum standards, whith which I happen to agree in principle.
Yawn..
Konnichiwa,
Sorry, but I take issue here. I for one do not support the davertising claims that the "walls form the horn mouth" to justify the manufacture and sale of foreshortened horns. I clearly made that point earlier in the thread.
I do not sell horns. The walls DO in fact form the horn mouth. Again you are incorrect. AFA the sell of foreshortened bass horns, show me one that I can buy that is full sized.
If the walls supply the "waveguide" than at the relevant frequencies your horn has ceased to be a horn and become (more or less) omnidirectional.
False. As I said before the floor and walls form the "waveguide" and if horn was omni-directional it would have the same response to a full 360 degrees. It does not - therefore it is not a monopole. If you read what I wrote you would understand this without question and agree. Instead you'd rather use this non-arguement.
It is not intended to be directional.
That was my intention. How can this be disputed?
In free or halve space? Then you don't need any walls to supply the "hornmouth".
It is in 1/8th space.
The Sub in my system is aimed purely at filling in the lowest octave and to match only the SPL of the main system (which due to the limited cone surface is not that high).
I agree
Well, the retention of directivity control with frequency of a given horn (especially the kind you use) is directly proportional to the main dimensions. Hence a horn that is narrow but tall has good directivity control at fairly low frequencies in the vertical plane but poor directivity control at fairly low frequencies in the horizontal plane.
Of course this is true to an extent -- problem with your argument is the parallel vertical sidewalls do in fact form a waveguide and are in fact directional and there is in fact an alteration in the horizontal response beyond placing the driver on a flat plane such as your open baffle scheme.
The kind of design you use is (was?) quite common in PA stacks and attained in it's normal use (lying down compared to your "standing up" application) significant vertical pattern control at low frequencies (near the horn cutoff) only with several units stacked (which is the intended use). As you have changed the orientation your horns will experience a material shifting in directivity with frequency, though the fairly narrowband use will keep that to a minimum.
Yawn....
At a guess I'd expect the hight (in your arrangement width) of the Horn to be around 0.5m with an attendant loss of directivity control (and progressive reversion to omnidirectional radiation in the relevant plane) at around 170Hz.
That is a guess. It has much less output within it's operating range at 90, 120 and 180 degrees compared to on axis than a monopole omnidirectional loudspeaker.
No, we ARE however talking about the directivity control behaviour of a tall and narrow sound source, of which slot radiators and ribbons are a special case. The same principles apply, as you will find on perusal of the relevant literature.
A slot ribbon normally does not have a horn attached to it -- when it does the directivity is altered as it is with my mibass horns.
I use Subwoofers because when designing my Dipoles I made a concious desicion that I would limit the LF extension (in room) to -6db @ 50Hz and the Drivers used have a Fs of 50Hz, so no matter what sort of dipole or baffle you place them in there will ALWAYS be a requirement for a Subwoofer to cover the lowest octave.
So the addition of a subwoofer (I personally at home use a single dual 12" "URPS" type unit) is part of the design brief. At the Show where the picture was taken we used the REL Quake's (one per channel) for good looks and commercial availability. The system did extremely well I'd like to add in a rather large room top to bottom, much better than I had expected.
Yawn... I'm glad you like it! Did you sell any????????
You may find them whatever you like. I merely observe the pertinent facts, you do not have to LIKE them or find them anything. Facts remain ojective regardless of how we percieve them.
Double yawn......
Simply based on the inability of your horn to provide directivity control at low frequencies in one plane (which in your case is the horizontal one) I think we can safely disregard the directivity argument. As for ease of drive, this would remain to be investigated with a real system.
I have one here and have verified my facts. You on the other hand are guessing.
To your PERSONAL TASTE.
And to yours
Actually, with a long enough window ETF will display any number of the various RTXX settings. I do not own the software, so measurements where done by a (Audio)Friend.
As he had done many he suspected measurement anomalies when a dipole speaker failed to show the usual behaviour with RT60. Several re-measuremnets later and wirh more dipole systems measured he concluded that the fairly flat RT60 (and shorter) is a byproduct of the dipoles operation, something I find to hold both practical and theoretical. In order to measure my current system I'll have invite him around, which shall be interresting anyway.
Please do, then you can state some facts rather then guess!
Beacuse you measure it the same way as above 200Hz. Room modes do not make reverb time measurements inaccurate, they simply increase the reverb time and this is a rather accurate statement and observation of what they do. This was the point of my argument BTW.
This is false. There is no reverberent field so RT60 cannot be measured properly -- too much direct sound, rooms not big enough, room modal interferance, and interfarence between modes is a start.
I take it that you would wish to inform the AES, EBU and IRT of the errors of their ways? Go ahead. The Document comes from the German "Verband Deutscher Tonmeister" (Society of German Sound Engineers), for all intent and purpose the German equivalent of (USA) AES. The VDT is generally a highly respected professional organisation for Sound Engineers with a long standing and extensive record on acosutical research covering recording, transmission and reproduction of sound.
No, I don't care
I tend to be at odds usually especially with the AES/JAES about a number of issues and their general approach to "fringe" issues, however there is a lot of solid, well backed research found within the AES and other similar organisations and I may be forgiven for considering the results of such research to be of more weight than those of individuals/companies who usually have commercial interests in promoting views that contradict the extant research.
If you want I can find plenty of information at AES that proves RT60 is irrelavent to measure below 200 cycles in a small room.
Neither myself nor the VDT claim that the referenced document is a complete and comprehensive specification, it merely sets out minimum standards, whith which I happen to agree in principle.
Yawn..
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