Re: Poor man's options...
Hi
This one at least is really outstanding in its speed. roughly 3.5 times the Fostex / Dynaudio examples above.
The membrane material Lynn does not like nor does he like the voice coil former to be aluminium ( not outlined in the datasheet but common to RCF ) nor does he like peaky cone breakup telling from his statements so far....
Greetings
Michael
Hi
Greggo said:
This one at least is really outstanding in its speed. roughly 3.5 times the Fostex / Dynaudio examples above.
The membrane material Lynn does not like nor does he like the voice coil former to be aluminium ( not outlined in the datasheet but common to RCF ) nor does he like peaky cone breakup telling from his statements so far....
Greetings
Michael
Hi Russel,
I can surely imagine the things you mention in the qoute on the Phy-hp. This is somehow my experience with them too with most tweeter I have used with them. Yes, they beam, yes they don't have a character that alows them to be crossed with a ribbon (I have tried the Raven R2 and the Jordanow VLD13 and some other one I can't recall). In this case it sure sounds better when crossed over at somewhere between 3 and 5 kHz, as low as the ribbon still has some body in it sound character.
I'm now using my BMS4540nd on a small 16cm waveguide and let them overlap with the phy's to about 4,5kHz and then correct the whole thing with my dsp crossover. Yes this sounds a bit strange and this solution is totaly based on dsp power, I know, and I can't do the same passivly.
I can surely imagine the things you mention in the qoute on the Phy-hp. This is somehow my experience with them too with most tweeter I have used with them. Yes, they beam, yes they don't have a character that alows them to be crossed with a ribbon (I have tried the Raven R2 and the Jordanow VLD13 and some other one I can't recall). In this case it sure sounds better when crossed over at somewhere between 3 and 5 kHz, as low as the ribbon still has some body in it sound character.
I'm now using my BMS4540nd on a small 16cm waveguide and let them overlap with the phy's to about 4,5kHz and then correct the whole thing with my dsp crossover. Yes this sounds a bit strange and this solution is totaly based on dsp power, I know, and I can't do the same passivly.
Just in case
Lynn,
Just in case you are willing to give three of the four (all but the Audax PR170M0) a listen and evaluation like you would the larger drivers you are considering, I would be willing to purchase one each of the three of them from US Speaker and have them shipped to you. You keep them, send them back to me whenever you feel like it, or send them on to someone else who posts detailed driver performance data on a web site, whatever you think is best....
An open offer for the duration of this thread. You can PM me or send a note to greg_c_jensen at yahoo dot com if you would like to take me up on it.
Like I said in my previous post, I am very curious, but I know that I don't have the equipment, experience, expertise to do any kind of evaluation myself that would be worth posting here.
Lynn,
Just in case you are willing to give three of the four (all but the Audax PR170M0) a listen and evaluation like you would the larger drivers you are considering, I would be willing to purchase one each of the three of them from US Speaker and have them shipped to you. You keep them, send them back to me whenever you feel like it, or send them on to someone else who posts detailed driver performance data on a web site, whatever you think is best....
An open offer for the duration of this thread. You can PM me or send a note to greg_c_jensen at yahoo dot com if you would like to take me up on it.
Like I said in my previous post, I am very curious, but I know that I don't have the equipment, experience, expertise to do any kind of evaluation myself that would be worth posting here.
Bud, thanks for your summary of the EnABLE treatment of the Lowther DX4 drivers. I am tempted to experiment with this, but I cannot now because I am in the middle of an extensive home remodeling project. I may follow up with this next year when all this remodeling work is completed.
Perhaps others will experiment in the meantime and be additional guinnea pigs with this technology. It would be interesting to test the conventional whizzer version as well as the whizzerless version to see what final set of drivers would be best.
I understand that Lowther America has experimented with different drivers treated with the EnABLE technology. I could always stop by his place for a listen...
Retsel
Perhaps others will experiment in the meantime and be additional guinnea pigs with this technology. It would be interesting to test the conventional whizzer version as well as the whizzerless version to see what final set of drivers would be best.
I understand that Lowther America has experimented with different drivers treated with the EnABLE technology. I could always stop by his place for a listen...
Retsel
Phy HP drivers
Hey Lynn,
The late great Dr Gizmo wrote about a speaker built around the PHY driver> here is a link to the review written in his usual style javascript:smilie('
')
smile
http://www.meta-gizmo.com/Tri/speak/frog.html
Hey Lynn,
The late great Dr Gizmo wrote about a speaker built around the PHY driver> here is a link to the review written in his usual style javascript:smilie('
')smile
http://www.meta-gizmo.com/Tri/speak/frog.html
Hey Kevin - funny article!
Alas I have not yet heard the PHY drivers, didn't get time to at RMAF. There is a guy here on Maui who has a pair on OB. Hope to hear them sometime.
Keith Aschenbrenner of Auditorium 23 is a cool guy who used to hang with the same crew I did in Paris, years ago. Keith builds all his speakers with PHY drivers, most of them open baffle. They get very, very good reviews. Just FYI.
Alas I have not yet heard the PHY drivers, didn't get time to at RMAF. There is a guy here on Maui who has a pair on OB. Hope to hear them sometime.
Keith Aschenbrenner of Auditorium 23 is a cool guy who used to hang with the same crew I did in Paris, years ago. Keith builds all his speakers with PHY drivers, most of them open baffle. They get very, very good reviews. Just FYI.
panomaniac said:
Interesting site, I would love to hear these. I have never heard the PHY-HP speakers (or the 18sound for that matter) would really like to. It will be fun to hear the reports from Lynn on the various speakers he will be evaluating.
BTW Harvey was quite a character. His website is well worth browsing lots of interesting ideas and thoughts about DHT's in there., as well as his love of Alnico speakers. I imagine he would have loved the current interest in field coils, neo magnets and permaalloy cores for xformers.
Right Angle
Awhile back in this thread, mutiple woofers on open baffles was discussed. Adding one woofer each at floor level & at right angle to the outside rear of the existing woofers was suggested by Lynn. I've tried that configuration and have found the bass eminates 'between' the speakers, & reduces the 'stage' width. Reversing the polarity of the added woofers has the bass eminating to the outside of the speakers, widening the 'stage'.
I hope I have described this well enough to be understood.
Since I'm trying for the best arrangement of the woofers at floor level, I'm now planning on relocating the second woofers to the rear of the first woofers in a magnet-to-magnet configuration. In theory, would I expect better bass with push-push or push -pull wiring of the woofers in that configuration?
dobias
Awhile back in this thread, mutiple woofers on open baffles was discussed. Adding one woofer each at floor level & at right angle to the outside rear of the existing woofers was suggested by Lynn. I've tried that configuration and have found the bass eminates 'between' the speakers, & reduces the 'stage' width. Reversing the polarity of the added woofers has the bass eminating to the outside of the speakers, widening the 'stage'.
I hope I have described this well enough to be understood.
Since I'm trying for the best arrangement of the woofers at floor level, I'm now planning on relocating the second woofers to the rear of the first woofers in a magnet-to-magnet configuration. In theory, would I expect better bass with push-push or push -pull wiring of the woofers in that configuration?
dobias
Zen Mod said:
I have some text about open baffle written by Lukas "The Lampizator" that does not seem to be on his website. I'll dig it up and send it to you.
EDIT: No need for me to send, here is a link to the page:
http://www.lampizator.eu/SPEAKERS/Practical tips loudspeaker DIY.html
OB Lampizator Page
Don't know if it's the same that Variac has. We should compare notes. =)
Hi all, sorry for the silence - my wife and I went out to Boulder, I was looking at getting a new standard-zoom lens for my Pentax K10D (either the Pentax 16-45mm or the Sigma 17-70mm), she persuaded me to stop at a car dealership, and well, we ended up getting a new car instead. Been learning about the big new toy instead of the smaller new toy.
Still going through all the written material, sonic impressions, and new-friends-met at the RMAF. It takes a couple of weeks to decompress from this kind of thing and let the impressions sort themselves out. It was especially nice meeting Hugh Grant of AKSA (Austalia), Alexander of RAAL (Serbia), Panomaniac (Maui), and Edward West (Seattle) - first time for all of these gentlemen, all really bright and personable. Also old school week for all my other hifi pals, hi there again, it was great to see you!
Regarding the topic at hand, playing games with the LF drivers has the effect of steering the null (if any) in different directions. Attenuating the rear wave shifts the null towards the back, depending on the (frequency-dependent) magnitude of the attenuation. An exact 6 dB attenuation results in a cardioid with the null directly behind the speaker system. This null-steering business is going to have a strong effect on room interaction as well as LF spatial perception.
My current reservations about drivers on the side walls of the baffle are about delayed arrival times for the side drivers, in addition to null-steering effects. It's probably less significant for drivers low-passed below 160 Hz, but for frequencies higher than that, I'm a bit concerned about re-introducing box modes and having blurred first-arrival wavefronts in the midbass region. Since room modes are also at their worst in this region, I can see the merit of systems that have relatively few drivers and a polar pattern somewhere between dipole and cardioid. Unfortunately, the inherent and inescapable 6 dB/octave rolloff of dipoles also requires a substantial increase in radiating area compared to monopoles (drivers in a box or large LF horn).
That's why I've been slowly drifting towards a tight array of 3 or 4 bass drivers, and probably taking advantage of the variable-geometry idea to keep the polar pattern from closing in too much in the 300 to 1 kHz region. As mentioned earlier, I'm not in the 90-degree polar angle camp - I favor much wider dispersion, simply because speakers with intentionally narrower dispersion angles sound spatially "closed-in" to me.
I'm kind of sensitive to this because of my background in designing quadraphonic decoders. The key goal with a well-designed multichannel system is a smooth spatial presentation of room reverberation - no hot spots, no blank regions either, with reasonably uniform spatial impression throughout the room, giving a plausible impression of a real performing space. The severe defect of modern multichannel is a gross deficiency in the depth dimension - sometimes no more than a couple of feet, heard a lot of that at the RMAF - and a tendency to "detent" towards the loudspeaker, collapsing the ambient impression of a real space.
Since I starting designing loudspeakers after my Shadow Vector SQ decoder project, I've always aimed for a realistic overall spatial impression over a large portion of the room, with reasonably good (but not cookie-cutter) direct images, and tonality in accordance with classical music (first) and popular music (second).
Modern speakers that follow the "controlled-dispersion" school just sound wrong to me, with truncated and closed-in impressions of the performing space. Going from two-speaker to multichannel spreads the spatial defect over a wider area, making it more noticeable, not less. A 270-degree arc of spatial impression that is 2 feet deep sounds grotesquely wrong - it's bad enough over a 50-degree arc, and much worse over a larger arc.
The worst of all is the misbegotten THX philosophy of completely different polar patterns for center, left, right, and surround speakers - a simple pan from one location to another leads to bizarre spatial distortions as the sound moves around. What's really awful is the impression of the front and rear halves of the room having completely different acoustics, like two dissimilar rooms joined together. This is unpleasant enough for popular music, and makes classical music unlistenable - Dolby Digital, with its heavy 10:1 lossy-compression ratios and a twenty-year-old algorithm originally designed for HDTV audio, pretty much finishes the job.
I'm spoiled enough to remember BBC, EMI, and CBS research-lab all-analog surround sound coming from Studer and Ampex mastertapes. Modern THX/Dolby sounds like five AM radios scattered around the room - not even hifi, and well below a competent late-Fifties system playing half-track tape.
You can see how strongly I disagree with the THX and Toole-school loudspeaker design. The overall tonal character may or may not be OK, but the spatial presentation, particularly of room-sound ambience, just sounds completely wrong, and nothing like any real space I've ever heard.
How does that affect the new dipole/quasicardioid system? I'm aiming for clean first-arrival sound, with low coloration and reasonable freedom from standing waves, HOM's, and other horn/cabinet artifacts, and a realistic spatial impression for the musicians and the space they're performing in.
This isn't a particularly novel goal, and a fair number of other speakers aim in this direction too. What's different is I'd like to have a wide dynamic range as well - and this is different, since high-efficiency speakers traditionally come out of PA and studio-monitor schools of design, where controlled (narrow) directivity are highly desirable qualities.
Still going through all the written material, sonic impressions, and new-friends-met at the RMAF. It takes a couple of weeks to decompress from this kind of thing and let the impressions sort themselves out. It was especially nice meeting Hugh Grant of AKSA (Austalia), Alexander of RAAL (Serbia), Panomaniac (Maui), and Edward West (Seattle) - first time for all of these gentlemen, all really bright and personable. Also old school week for all my other hifi pals, hi there again, it was great to see you!
Regarding the topic at hand, playing games with the LF drivers has the effect of steering the null (if any) in different directions. Attenuating the rear wave shifts the null towards the back, depending on the (frequency-dependent) magnitude of the attenuation. An exact 6 dB attenuation results in a cardioid with the null directly behind the speaker system. This null-steering business is going to have a strong effect on room interaction as well as LF spatial perception.
My current reservations about drivers on the side walls of the baffle are about delayed arrival times for the side drivers, in addition to null-steering effects. It's probably less significant for drivers low-passed below 160 Hz, but for frequencies higher than that, I'm a bit concerned about re-introducing box modes and having blurred first-arrival wavefronts in the midbass region. Since room modes are also at their worst in this region, I can see the merit of systems that have relatively few drivers and a polar pattern somewhere between dipole and cardioid. Unfortunately, the inherent and inescapable 6 dB/octave rolloff of dipoles also requires a substantial increase in radiating area compared to monopoles (drivers in a box or large LF horn).
That's why I've been slowly drifting towards a tight array of 3 or 4 bass drivers, and probably taking advantage of the variable-geometry idea to keep the polar pattern from closing in too much in the 300 to 1 kHz region. As mentioned earlier, I'm not in the 90-degree polar angle camp - I favor much wider dispersion, simply because speakers with intentionally narrower dispersion angles sound spatially "closed-in" to me.
I'm kind of sensitive to this because of my background in designing quadraphonic decoders. The key goal with a well-designed multichannel system is a smooth spatial presentation of room reverberation - no hot spots, no blank regions either, with reasonably uniform spatial impression throughout the room, giving a plausible impression of a real performing space. The severe defect of modern multichannel is a gross deficiency in the depth dimension - sometimes no more than a couple of feet, heard a lot of that at the RMAF - and a tendency to "detent" towards the loudspeaker, collapsing the ambient impression of a real space.
Since I starting designing loudspeakers after my Shadow Vector SQ decoder project, I've always aimed for a realistic overall spatial impression over a large portion of the room, with reasonably good (but not cookie-cutter) direct images, and tonality in accordance with classical music (first) and popular music (second).
Modern speakers that follow the "controlled-dispersion" school just sound wrong to me, with truncated and closed-in impressions of the performing space. Going from two-speaker to multichannel spreads the spatial defect over a wider area, making it more noticeable, not less. A 270-degree arc of spatial impression that is 2 feet deep sounds grotesquely wrong - it's bad enough over a 50-degree arc, and much worse over a larger arc.
The worst of all is the misbegotten THX philosophy of completely different polar patterns for center, left, right, and surround speakers - a simple pan from one location to another leads to bizarre spatial distortions as the sound moves around. What's really awful is the impression of the front and rear halves of the room having completely different acoustics, like two dissimilar rooms joined together. This is unpleasant enough for popular music, and makes classical music unlistenable - Dolby Digital, with its heavy 10:1 lossy-compression ratios and a twenty-year-old algorithm originally designed for HDTV audio, pretty much finishes the job.
I'm spoiled enough to remember BBC, EMI, and CBS research-lab all-analog surround sound coming from Studer and Ampex mastertapes. Modern THX/Dolby sounds like five AM radios scattered around the room - not even hifi, and well below a competent late-Fifties system playing half-track tape.
You can see how strongly I disagree with the THX and Toole-school loudspeaker design. The overall tonal character may or may not be OK, but the spatial presentation, particularly of room-sound ambience, just sounds completely wrong, and nothing like any real space I've ever heard.
How does that affect the new dipole/quasicardioid system? I'm aiming for clean first-arrival sound, with low coloration and reasonable freedom from standing waves, HOM's, and other horn/cabinet artifacts, and a realistic spatial impression for the musicians and the space they're performing in.
This isn't a particularly novel goal, and a fair number of other speakers aim in this direction too. What's different is I'd like to have a wide dynamic range as well - and this is different, since high-efficiency speakers traditionally come out of PA and studio-monitor schools of design, where controlled (narrow) directivity are highly desirable qualities.
JBL
http://manuals.harman.com/JBL/HOM/Product Information/Brochure_Everest_Eng.pdf
Although not an open baffle, the current JBL flagship has some interesting ideas that may be applicable to Lynn's design. Right now I'm listening to an MWW open baffle with 2x JBL 123a-1's and a Visaton Ti-100. Simultaneously the ugliest looking and most beautiful sounding things I have had in my living room. They don't meet the sensitivity requirements for Lynn, but they are very nice.
Now that Lynn is feeling a little better, I am curious to see where this will be going,
C
http://manuals.harman.com/JBL/HOM/Product Information/Brochure_Everest_Eng.pdf
Although not an open baffle, the current JBL flagship has some interesting ideas that may be applicable to Lynn's design. Right now I'm listening to an MWW open baffle with 2x JBL 123a-1's and a Visaton Ti-100. Simultaneously the ugliest looking and most beautiful sounding things I have had in my living room. They don't meet the sensitivity requirements for Lynn, but they are very nice.
Now that Lynn is feeling a little better, I am curious to see where this will be going,
C
Right Angle
Salas,
Thank you for responding.
Yes, that is another arrangement I may try.
I think that the present 90 degrees causes the phase problem. I meant to add in the previous post that changing the 90 degree rear woofers to out-of-phase makes the sound stage vague, or smeared.
I had hoped to put third 12" woofers to the opposite sides, making a three sided enclosures, but I'm wondering what problems I'd encounter having three woofers with their backs so close to each other.
I'm afraid putting the rear woofers at 45 degrees on each side would make the baffles a traffic hazard in my living room & would cause problems with my long suffering wife.
My arrangement started with Wharfedale Super 12 CS-AL full ranges on top with no crossover, below them are 12" Wharfedale woofers with 4 mH air wound coils in series for a 280 Hz pass through. 3" Super tweeters, mounted vertically behind the baffles, are wired with 3.9 mF in series for a 5,000 Hz pass through.
When I added the second woofers I wired an additional 4 mH coil to get a 140 Hz augment. If I add the third woofers they would also go to 140 Hz.
Besides adequate bass,I'm hoping for a small footprint of the final speaker arrangement.
I'm very pleased with the open clear sound so far.
Boosting the bass with the amplifier seems to be counter productive. That's why I'm looking for three 12" woofers to augment the 12" full range without bass boost.
dobias
Salas,
Thank you for responding.
Yes, that is another arrangement I may try.
I think that the present 90 degrees causes the phase problem. I meant to add in the previous post that changing the 90 degree rear woofers to out-of-phase makes the sound stage vague, or smeared.
I had hoped to put third 12" woofers to the opposite sides, making a three sided enclosures, but I'm wondering what problems I'd encounter having three woofers with their backs so close to each other.
I'm afraid putting the rear woofers at 45 degrees on each side would make the baffles a traffic hazard in my living room & would cause problems with my long suffering wife.
My arrangement started with Wharfedale Super 12 CS-AL full ranges on top with no crossover, below them are 12" Wharfedale woofers with 4 mH air wound coils in series for a 280 Hz pass through. 3" Super tweeters, mounted vertically behind the baffles, are wired with 3.9 mF in series for a 5,000 Hz pass through.
When I added the second woofers I wired an additional 4 mH coil to get a 140 Hz augment. If I add the third woofers they would also go to 140 Hz.
Besides adequate bass,I'm hoping for a small footprint of the final speaker arrangement.
I'm very pleased with the open clear sound so far.
Boosting the bass with the amplifier seems to be counter productive. That's why I'm looking for three 12" woofers to augment the 12" full range without bass boost.
dobias
In general, the front facing 45deg inwards angle, is aiding coupling between woofers (more dBs and coherency), and is going to reduce the sheer width of the baffle base in exchange of some depth, which is normally non human traffic space behind the speakers. You can also hinge the two halves in the middle and play with the angle, until it sounds best in room.
Regards.
Regards.