hmmmm so many tweeters , so little time.....
Here are a couple of crazy ideas.... if we are making a SOTA Assault ...
-- Maybe the two pair of the Purifi 6.5's -- with 2 Pair of NEO10 Mids , and with 2 to 3 Pairs of NEO3 Tweeters -- ( for High SPL's , and low distortion you know ).
- Soo --- WW-MM-TT-MM --
- Or put the Raven in the mix -- WW-MM-T-R-T-MM ???
- ( I like to rock out once in a while ) --
Here are a couple of crazy ideas.... if we are making a SOTA Assault ...
-- Maybe the two pair of the Purifi 6.5's -- with 2 Pair of NEO10 Mids , and with 2 to 3 Pairs of NEO3 Tweeters -- ( for High SPL's , and low distortion you know ).
- Soo --- WW-MM-TT-MM --
- Or put the Raven in the mix -- WW-MM-T-R-T-MM ???
- ( I like to rock out once in a while ) --
- I thought I'd share this , GR Research has an interesting Idea... they made a little Studio Monitor using one of their Mid-woofers and their new Redesign of the NEO3 Tweeter which most agree is a Great sounding tweeter - ( also one that won't break the bank ) -
- The woofer is in it's own compartment, but the divider between the top of the Mid-Woofer compartment and the tweeter is slanted up so the NEO3 can radiate back and up... and those that have heard it say it adds some very nice detail and " spaciousness " to the sound. Might be a Great sounding combo with the Purifi driver!
- ( spaciousness - is that a word?) -
- The woofer is in it's own compartment, but the divider between the top of the Mid-Woofer compartment and the tweeter is slanted up so the NEO3 can radiate back and up... and those that have heard it say it adds some very nice detail and " spaciousness " to the sound. Might be a Great sounding combo with the Purifi driver!
- ( spaciousness - is that a word?) -
Attachments
Neat stuff. Basically a dipole tweeter with upwards reflected back energy for spaciousness. I have played with this by adding a dome super tweeter aimed straight up.
Spaciousness is a real word.
Is the NEO3 the one by B&G or a different brand? I know Dayton has an alternative brand that is now more cost effective and looks almost identical.
Spaciousness is a real word.
Is the NEO3 the one by B&G or a different brand? I know Dayton has an alternative brand that is now more cost effective and looks almost identical.
Details regarding the differences between GR Reseach’s and GRS’s versions of the “NEO3” (and interesting experiments using 3D printed waveguides).
GRS-3 vs Neo 3
Page 4 of that AudioCircle thread has an interesting event. A little over one hour in the sun while making outdoor measurements on the GRS version caused delamination of the ‘voice coil’ off driver membrane. Danny Richie (owner & chief engineer GR Research) commented “that is why we use Kapton film on ours instead of Kaladax.” In other threads Danny has also stressed he specifies pure copper spade lugs on units he has manufactured for GR Research. He’s kind of a fanatic about keeping magnetic materials out of the signal path.
Couple of advanced build threads NX Studio
Sonicjoy's NX Studio build. With photos.
NX Studio Build Notes
GRS-3 vs Neo 3
Page 4 of that AudioCircle thread has an interesting event. A little over one hour in the sun while making outdoor measurements on the GRS version caused delamination of the ‘voice coil’ off driver membrane. Danny Richie (owner & chief engineer GR Research) commented “that is why we use Kapton film on ours instead of Kaladax.” In other threads Danny has also stressed he specifies pure copper spade lugs on units he has manufactured for GR Research. He’s kind of a fanatic about keeping magnetic materials out of the signal path.
Couple of advanced build threads NX Studio
Sonicjoy's NX Studio build. With photos.
NX Studio Build Notes
- I thought I'd share this , GR Research has an interesting Idea... they made a little Studio Monitor using one of their Mid-woofers and their new Redesign of the NEO3 Tweeter which most agree is a Great sounding tweeter - ( also one that won't break the bank ) -
- The woofer is in it's own compartment, but the divider between the top of the Mid-Woofer compartment and the tweeter is slanted up so the NEO3 can radiate back and up... and those that have heard it say it adds some very nice detail and " spaciousness " to the sound. Might be a Great sounding combo with the Purifi driver!
- ( spaciousness - is that a word?) -
Think I'm with hallcon83 on this - great idea.
Did some research on the Heil AMT's:
Quote:
Should come as no surprise really.I believe that it's worthwhile to list the downside to using AMT drivers on top of Cornwalls:
1) The AMTs really aren't as capable in very high SPL as the original Klipsch drivers. If you find yourself regularly listening at 105+ dB at your listening position (for instance, daily or perhaps more than once a week), I'd rethink using AMTs because their measured distortion levels will probably be higher than the Klipsch drivers/horns at those SPLs. This isn't really that significant a factor, but it is one that you should consider for your application.
2) The AMTs have a real problem in the vertical direction coverage. I'm working on dealing with this using horn closures/extensions, but so far, it's pretty complicated. I'd strongly recommend listening on-axis or within ±10-15 degrees. I'd be careful of putting anything acoustically reflective just above these drivers, since they will reflect a tonally imbalanced off-axis acoustic energy which could affect your listening pleasure. I'd be in favor of adding absorption to low ceilings and/or furnishings that are in the near field of these tweeters in the vertical direction.
Source: Heil Air motion transformer for Cornwalls - Page 8 - Technical/Modifications - The Klipsch Audio Community1) The AMTs really aren't as capable in very high SPL as the original Klipsch drivers. If you find yourself regularly listening at 105+ dB at your listening position (for instance, daily or perhaps more than once a week), I'd rethink using AMTs because their measured distortion levels will probably be higher than the Klipsch drivers/horns at those SPLs. This isn't really that significant a factor, but it is one that you should consider for your application.
2) The AMTs have a real problem in the vertical direction coverage. I'm working on dealing with this using horn closures/extensions, but so far, it's pretty complicated. I'd strongly recommend listening on-axis or within ±10-15 degrees. I'd be careful of putting anything acoustically reflective just above these drivers, since they will reflect a tonally imbalanced off-axis acoustic energy which could affect your listening pleasure. I'd be in favor of adding absorption to low ceilings and/or furnishings that are in the near field of these tweeters in the vertical direction.
Personally I'd like to see good constant directivity over a wide area, both vertical and horizontal.
Another idea...Beyma CP-09? Just a shame it's efficiency would have to be brought in line. Might be easier to time align with the horn loading though?
Visaton TL16H seems like a push for the crossover, would perhaps need to be three way with a PTT4.0W04 included.
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Some folks have addressed the vertical dispersion and output limit of the Heils by stacking up a pair of them:
Double Stack ESS AMT-1 with Wings--Possible Kit for Heritage - Technical/Modifications - The Klipsch Audio Community
Bill
Double Stack ESS AMT-1 with Wings--Possible Kit for Heritage - Technical/Modifications - The Klipsch Audio Community
Bill
- Yes , I've been following along the Stacked AMT driver threads with a lot of interest trying to make up my mind on whether or not to go for it ....
- what's really strange about the situation is the guys who have chosen to replace their different kinds of Horn setups and other designs - like Oris horns, Klipsch Horns tops etc. , all Really like them. - But I was asking a professional speaker designer about some other things and in passing mentioned the dual stacked AMT's as an option...
- His response was why? - it would cause a Lot of Comb Filtering and wouldn't sound very good.
-- that really confused me -- ??? -
- what's really strange about the situation is the guys who have chosen to replace their different kinds of Horn setups and other designs - like Oris horns, Klipsch Horns tops etc. , all Really like them. - But I was asking a professional speaker designer about some other things and in passing mentioned the dual stacked AMT's as an option...
- His response was why? - it would cause a Lot of Comb Filtering and wouldn't sound very good.
-- that really confused me -- ??? -
Looking at the stacked Heils there’s actually very little distance between them:
So if there is comb filtering it’s not as obvious to me that it would be present here, compared to something like a line array. This is my unqualified guess!
What also hasn’t been answered is how much stacking the Heil AMT1’s increases the vertical directivity. Does it go from +/-15degrees to +/-30degrees when double stacked?
Check out Mundorf AMT17D: Mundorf AMT17D2.2 Dipole Air Motion Tweeter
Cheaper in Europe mind
So if there is comb filtering it’s not as obvious to me that it would be present here, compared to something like a line array. This is my unqualified guess!
What also hasn’t been answered is how much stacking the Heil AMT1’s increases the vertical directivity. Does it go from +/-15degrees to +/-30degrees when double stacked?
Check out Mundorf AMT17D: Mundorf AMT17D2.2 Dipole Air Motion Tweeter
Cheaper in Europe mind
Just checking - 15cm or 15degrees?
15cm good be very good, but would depend on listening distance. Any source?
- Yes , I've been following along the Stacked AMT driver threads with a lot of interest trying to make up my mind on whether or not to go for it ....
- what's really strange about the situation is the guys who have chosen to replace their different kinds of Horn setups and other designs - like Oris horns, Klipsch Horns tops etc. , all Really like them. - But I was asking a professional speaker designer about some other things and in passing mentioned the dual stacked AMT's as an option...
- His response was why? - it would cause a Lot of Comb Filtering and wouldn't sound very good.
-- that really confused me -- ??? -
A couple of points on the stacked AMT issue.
First hallcon83 don’t be confused that some use stacked AMTs and are thrilled with the result while others cite comb filtering. As is often the case in this passion and/or profession we call HiFi there are two opposing camps on this issue. In the first camp longer array adherents typically acknowledge there is comb filtering but tend to dismiss it as an effect at one point in space and when all the angles and outputs combing in room (i.e. the power response) the undeniable benefits of more radiating area outweigh the comb filter downside. The second camp points out if one is seated and not dancing around you are on one vector and so effected by that frequency(s) comb notches or peaks. These two opposing camps have been around for decades and I do not see them going away anytime soon.
Secondly I will offer my opinion that bringing solutions developed for Klipsch Horns to a Purifi design one needs to keep in mind these are the proverbial apples vs. oranges. Specifically those Klipsch systems as the apples will have bass bins with efficiencies in the upper 90s or if the corner horn is in play perhaps over 100 dB/w/m. Then we have as the oranges our PTT6.5W04 running 88.5 dB SPL@2.83Vrms/1m. I suspect the Klipsch guys are stacking AMTs to get the mid/tweeter dB/w/m levels up to the range of the compression drivers + horn mids they are replacing. Bring that solution to a Purifi PTT6.5 powered system and your crossover will need to dump 10, 15, 20 dBs of signal straight to ground to pad the mid/tweeter down to match the bass. OK if one is bi-amping and using a Pass Zen one transistor amp for the mid-range and highs but with a high level crossover I find it an unfortunate compromise to send so much signal straight to the ground terminal.
PTT6.5W04 and the evil twins PTT6.5PR want to explode your speaker box.
Interesting result occurred during last Thursday’s audiophile night. For these listening sessions my music and HiFi enthusiasts’ friends Leo and Michael meet for dinner then we adjourn to one of our homes for listening. That night’s agenda was actually to compare the new PS Audio PerfectWave SACD Transport Michael has in as part of PS’ beta test program to my Media PC. Before you ask into both my Soekris ApS R2R dam1941 DAC and a PS Audio Stellar Gain Cell preamp/DAC the PerfectWave was more transparent, colorful, and dynamic vs the USB output of the Media PC.
For the testing we were using my Fi16v1 speakers I have posted about on this thread. Presently they are bi-amplified with Marchand Electronics Inc. crossover and four channels of Audio Crafters Guild amplification.
So Michael had brought the Reference Recordings CD ‘Copland 100’ by Eiji Oue conducting the Minnesota Orchestra. We used ‘Fanfare for the Common Man’ as a test track. With all the A vs. B switching the system was turned up, well and because audiophiles. When the big drum whacks hit it was literally stunning. Recall Fanfare starts with a drum hit. I do not know if that is a timpani, bass drum, or big 45” concert tom that thing is being hit HARD and the sound is loud and DEEP. The PTT6.5W04 and his PTT6.5PR minion’s response was ‘yeah, we got this’ and the result audiophile dream bass. Oh, too bad so sad with the task at hand comparing two data sources into two DACs we ‘have’ to listen to this four times.
There was one little glitch. I was sitting to the right and as the concussive bass hits would peak I heard a non-musical ‘bufftzz’ noise from the right speaker. Suspecting a leak past one of the passive radiator’s gaskets while we replayed the track I got up and standing by the speaker listened for the leak as the drummer had his fun. As the drum hit I jumped from being startled then laughed at what had occurred. I had absentmindedly rested my left hand on the top of the speaker so that when the bass hit rather than hear the leak I felt it as a jet of air was forced between the top and left side panels’ joint! Those cabinets are CNC cut but these prototypes had a CAD error so rather than a tongue and groove joint it’s a simple butt joint. The moral of the story is clamps and plenty of Titebond 3 are no match for PTT6.5W04 and a pair of PTT6.5PR when driven by 500 watts of power with a “Prof.” Johnson recording queued up. These boxes are slated to be rotated out of service while a new floor standing design is tested (details soon). I had already been toying with the idea of sealing and damping these panels with interior epoxy pours. That is obviously no longer an option rather a necessity while they are back in the workshop getting exterior finish upgrades.
As a final note checking the levels of bass we were luxuriating in Michael took out his phone and opened the sound level meter app he has installed. He reported “that was peaking at 108 dBs”. By unanimous consent of the listening panel I turned it down for the 3rd and 4th replay for our ears’ sake.
Interesting result occurred during last Thursday’s audiophile night. For these listening sessions my music and HiFi enthusiasts’ friends Leo and Michael meet for dinner then we adjourn to one of our homes for listening. That night’s agenda was actually to compare the new PS Audio PerfectWave SACD Transport Michael has in as part of PS’ beta test program to my Media PC. Before you ask into both my Soekris ApS R2R dam1941 DAC and a PS Audio Stellar Gain Cell preamp/DAC the PerfectWave was more transparent, colorful, and dynamic vs the USB output of the Media PC.
For the testing we were using my Fi16v1 speakers I have posted about on this thread. Presently they are bi-amplified with Marchand Electronics Inc. crossover and four channels of Audio Crafters Guild amplification.
So Michael had brought the Reference Recordings CD ‘Copland 100’ by Eiji Oue conducting the Minnesota Orchestra. We used ‘Fanfare for the Common Man’ as a test track. With all the A vs. B switching the system was turned up, well and because audiophiles. When the big drum whacks hit it was literally stunning. Recall Fanfare starts with a drum hit. I do not know if that is a timpani, bass drum, or big 45” concert tom that thing is being hit HARD and the sound is loud and DEEP. The PTT6.5W04 and his PTT6.5PR minion’s response was ‘yeah, we got this’ and the result audiophile dream bass. Oh, too bad so sad with the task at hand comparing two data sources into two DACs we ‘have’ to listen to this four times.
There was one little glitch. I was sitting to the right and as the concussive bass hits would peak I heard a non-musical ‘bufftzz’ noise from the right speaker. Suspecting a leak past one of the passive radiator’s gaskets while we replayed the track I got up and standing by the speaker listened for the leak as the drummer had his fun. As the drum hit I jumped from being startled then laughed at what had occurred. I had absentmindedly rested my left hand on the top of the speaker so that when the bass hit rather than hear the leak I felt it as a jet of air was forced between the top and left side panels’ joint! Those cabinets are CNC cut but these prototypes had a CAD error so rather than a tongue and groove joint it’s a simple butt joint. The moral of the story is clamps and plenty of Titebond 3 are no match for PTT6.5W04 and a pair of PTT6.5PR when driven by 500 watts of power with a “Prof.” Johnson recording queued up. These boxes are slated to be rotated out of service while a new floor standing design is tested (details soon). I had already been toying with the idea of sealing and damping these panels with interior epoxy pours. That is obviously no longer an option rather a necessity while they are back in the workshop getting exterior finish upgrades.
As a final note checking the levels of bass we were luxuriating in Michael took out his phone and opened the sound level meter app he has installed. He reported “that was peaking at 108 dBs”. By unanimous consent of the listening panel I turned it down for the 3rd and 4th replay for our ears’ sake.
Hi Norman,
Thanks for the great recounting of your audio get together. I wish I lived closer to my speaker and audio amp building buddies. We are spread out over the US and the world (WA, CA, VA, NY, Germany, Dhaka, and Melbourne).
Air leaks in my original PTT6.5 TL prompted me make a second one using mitered lock joints and PL Premium. No more Titebond and butt joints on critical joints anymore.
I had a leak on another TL and it was around the ledger that supported a removable rear panel with a gasket. The gasket was fine - it was the Titebond joint between the ledger and the main box that leaked. Jet of air is a good way to describe it. I used a candle to verify the leak:
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Thanks for the great recounting of your audio get together. I wish I lived closer to my speaker and audio amp building buddies. We are spread out over the US and the world (WA, CA, VA, NY, Germany, Dhaka, and Melbourne).
Air leaks in my original PTT6.5 TL prompted me make a second one using mitered lock joints and PL Premium. No more Titebond and butt joints on critical joints anymore.
I had a leak on another TL and it was around the ledger that supported a removable rear panel with a gasket. The gasket was fine - it was the Titebond joint between the ledger and the main box that leaked. Jet of air is a good way to describe it. I used a candle to verify the leak:
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Mundorf do this longer AMT (baffle less install), doesn't seem to do much for vertical dispersion. Perhaps some pads could be added top/bottom to aid dispersion?
Mundorf AMT27D1.1 Dipole Tweeter | Hifi Collective
This seems the best option for hallcon83's idea
Mundorf AMT25D1.1 Dipole Tweeter | Hifi Collective
Seems as though the AMT21CM2.1-C as used in SPK5 really is a very good match for dispersion. But I do love the dipole sound. Perhaps go bipole using two AMT21CM2.1-C should be considered.
Mundorf AMT27D1.1 Dipole Tweeter | Hifi Collective
This seems the best option for hallcon83's idea
Mundorf AMT25D1.1 Dipole Tweeter | Hifi Collective
Seems as though the AMT21CM2.1-C as used in SPK5 really is a very good match for dispersion. But I do love the dipole sound. Perhaps go bipole using two AMT21CM2.1-C should be considered.
Sorry, meant to say rear facing tweeter as opposed to bipole.
and the link I meant to give for Hallcon83's idea should have been for the Mundorf AMT23D6.1-R Dipole Tweeter
The Mundorf AMT25D1.1 is very interesting
"Long ribbons with open backs probably show some of the effect, but have limited frequency range and become acoustically large."
ORION++
AMT25D1.1 might well get over this limitation Linktwitz talks about with ribbons.
and the link I meant to give for Hallcon83's idea should have been for the Mundorf AMT23D6.1-R Dipole Tweeter
The Mundorf AMT25D1.1 is very interesting
"Long ribbons with open backs probably show some of the effect, but have limited frequency range and become acoustically large."
ORION++
AMT25D1.1 might well get over this limitation Linktwitz talks about with ribbons.
- Thanks guys , interesting discussion and good information. and I appreciate the help with the Comb Filtering issue...
--- My thinking on the stacked AMT's using the Waveguides was that I was considering going with an Active crossover , and since I wasn't using one amplifier , I could just turn the AMT's amplifier down to match the levels with the Purifi Mid-Woofers and their amplifier.
- Great story Norman!
- And it's Very good to know about the building pitfalls - the kind of joints used and what glues you guys are using!!
---- Since I am asking about confusing issues, when I was emailing the Professional Speaker Designer, I had mentioned several of the different design ideas I had regarding how to use my two pair of Purify 6.5 drivers........... and along with the statement about that you can't have two tweeters next to each other because of Comb Filtering,
--- he also said that
- " The 6.5" driver is really not suitable for use above 200Hz. It is just too heavy. And don't get caught up in the numbers. Distortion numbers are a drop in the bucket in the over all scheme of things involved."
--- And...
- "Again, really new woofers, but not ideal for mid-range or above."
---- So next I had written this
---- Many of the other guys at diyaudio have already built some speakers using the new drivers and comments on the Purifi speaker drivers have been Extremely positive ... of course they might be a little prejudiced - LOL........ But there are also several online reviewers that have also been very impressed with Purifi's demo speaker that they sent out,
--- And his response....
- " I know of a reviewer right now that just got one of those speakers and it sounds like it is pretty hard to listen to. He says the tweeter level is too hot and not that great at all. And the tweeter doesn't play down that low so the woofer has to play up high and it is not good at that at all."
---- the guy builds really well regarded speakers and has won a lot of awards........ but after his email reply I spent two days in a serious depression ... like I had totally wasted my - $1,000 that I spent on the drivers... I guess my insecurities got the better of me.
It is a strange thing that he says it can't be used above 200Hz. because it's too heavy.... I never realized that weight of a midrange is that important??
---- Looking for thoughts on a midrange drivers weight??
--- My thinking on the stacked AMT's using the Waveguides was that I was considering going with an Active crossover , and since I wasn't using one amplifier , I could just turn the AMT's amplifier down to match the levels with the Purifi Mid-Woofers and their amplifier.
- Great story Norman!
- And it's Very good to know about the building pitfalls - the kind of joints used and what glues you guys are using!!
---- Since I am asking about confusing issues, when I was emailing the Professional Speaker Designer, I had mentioned several of the different design ideas I had regarding how to use my two pair of Purify 6.5 drivers........... and along with the statement about that you can't have two tweeters next to each other because of Comb Filtering,
--- he also said that
- " The 6.5" driver is really not suitable for use above 200Hz. It is just too heavy. And don't get caught up in the numbers. Distortion numbers are a drop in the bucket in the over all scheme of things involved."
--- And...
- "Again, really new woofers, but not ideal for mid-range or above."
---- So next I had written this
---- Many of the other guys at diyaudio have already built some speakers using the new drivers and comments on the Purifi speaker drivers have been Extremely positive ... of course they might be a little prejudiced - LOL........ But there are also several online reviewers that have also been very impressed with Purifi's demo speaker that they sent out,
--- And his response....
- " I know of a reviewer right now that just got one of those speakers and it sounds like it is pretty hard to listen to. He says the tweeter level is too hot and not that great at all. And the tweeter doesn't play down that low so the woofer has to play up high and it is not good at that at all."
---- the guy builds really well regarded speakers and has won a lot of awards........ but after his email reply I spent two days in a serious depression ... like I had totally wasted my - $1,000 that I spent on the drivers... I guess my insecurities got the better of me.
It is a strange thing that he says it can't be used above 200Hz. because it's too heavy.... I never realized that weight of a midrange is that important??
---- Looking for thoughts on a midrange drivers weight??
@hallcon83:
I haven't heard the purifis yet. You are right, those who praise the builds they were given for testing may be biased.
But in principle the matter of (potentially) being biased applies to most opinions - or subjective 'evaluations' - regarding the merits/weaknesses of different driver types. Or different complete loudspeakers. And so on.
As far as I know there is absolutely NO objective reason why a driver with a relatively heavy diaphragm shouldn't be capable to reproduce the "best ever" midrange.
I haven't heard the purifis yet. You are right, those who praise the builds they were given for testing may be biased.
But in principle the matter of (potentially) being biased applies to most opinions - or subjective 'evaluations' - regarding the merits/weaknesses of different driver types. Or different complete loudspeakers. And so on.
As far as I know there is absolutely NO objective reason why a driver with a relatively heavy diaphragm shouldn't be capable to reproduce the "best ever" midrange.