Paul W said:
Sounds pretty impressive.
This would be great. Have some info how that assembly breaks up.
I've been pretty busy with other things but the concept still remains. Seems like 18N850 could be the woofer for me. Don't know of the setup thought. Dipole would be nice if placement allows it, less deep bass extension but more top end extension and less stress to mains compared to closed cabinet. But at least simulations suggest that driver should be pretty suitable to both...
Jussi
About the SLS12
Hi Jussi,
I recently measured the harmonic distortion of a few woofers, including the SLS12. I thought you might enjoy this little bit of information. You can see the plots at: Distortion measurements
I'll copy-paste the text I posted at Madisound. If I were to supply just the link, it would probably be offline within a few months. It always bugs me when I think I find something usefull in the archives and the external link has gone bad... 😉
Hi Jussi,
I recently measured the harmonic distortion of a few woofers, including the SLS12. I thought you might enjoy this little bit of information. You can see the plots at: Distortion measurements
I'll copy-paste the text I posted at Madisound. If I were to supply just the link, it would probably be offline within a few months. It always bugs me when I think I find something usefull in the archives and the external link has gone bad... 😉
And a little info on the test conditions:
Does anyone have an idea how to implement well operating and extended dipolebass in 3,7m deep, 2,6m high and 5,2m wide room? Listening direction isn't easy to change, we're having our TV set between the speakers and ~5m is a bit long way to watch it..
Top end extension up to 150Hz or even 200Hz. I guess that later one would require straight panel or just a minor H-baffle on it. Single BMS Pro 18N850 (or similar large PA woofer) on each side has crossed my mind. Very compact, about 50cm wide triangle shape from the top. Naturally displacement isn't enough for very deep bass but it should still be about 5dB better in brutal SPL compared to Orion. Peerless SLS stacks are also one solution but I don't know how to stack them to obtain required top end extension and still keep the overall construction in decent size.
Hans,
I noticed your measurements from Madi board. All of them seem very similar, not that much differences between them. Are they really that similar?
Jussi
Top end extension up to 150Hz or even 200Hz. I guess that later one would require straight panel or just a minor H-baffle on it. Single BMS Pro 18N850 (or similar large PA woofer) on each side has crossed my mind. Very compact, about 50cm wide triangle shape from the top. Naturally displacement isn't enough for very deep bass but it should still be about 5dB better in brutal SPL compared to Orion. Peerless SLS stacks are also one solution but I don't know how to stack them to obtain required top end extension and still keep the overall construction in decent size.
Hans,
I noticed your measurements from Madi board. All of them seem very similar, not that much differences between them. Are they really that similar?
Jussi
Member
Joined 2003
Jussi,
Here is curve of 18N850 straight from carton...not broken in at all. (Impedance scale is exaggerated.) Driver was free air, with magnet resting on two very large pillows.
Now I must continue work on baffles. 🙂
Paul
Here is curve of 18N850 straight from carton...not broken in at all. (Impedance scale is exaggerated.) Driver was free air, with magnet resting on two very large pillows.
Now I must continue work on baffles. 🙂
Paul
An externally hosted image should be here but it was not working when we last tested it.
Paul,
Looks pretty good. First major breakup just below 1Khz. Seems like it would work up to 200Hz without problems from there. Any development since this measurement?
I recall driver has vented structure behind the spider? So it shouldn't have turbulance problems in open baffle running large excursions.
Jussi
Looks pretty good. First major breakup just below 1Khz. Seems like it would work up to 200Hz without problems from there. Any development since this measurement?
I recall driver has vented structure behind the spider? So it shouldn't have turbulance problems in open baffle running large excursions.
Jussi
Member
Joined 2003
Jussi,
No sign of "wiggles" in BMS curves so I think these drivers will be fine to 200, maybe even 300. Yes there is distributed venting (many small holes) behind spider, but I think noise is easily silenced with wool felt of proper thickness.
Baffles are finished and ready for painting, but I am too busy with "real job" right now. I was in LA last week, now in Japan, next week Taiwan, then back to the US.
So, I hope to have them running around the end of this month.
Regards,
Paul
No sign of "wiggles" in BMS curves so I think these drivers will be fine to 200, maybe even 300. Yes there is distributed venting (many small holes) behind spider, but I think noise is easily silenced with wool felt of proper thickness.
Baffles are finished and ready for painting, but I am too busy with "real job" right now. I was in LA last week, now in Japan, next week Taiwan, then back to the US.
So, I hope to have them running around the end of this month.
Regards,
Paul
Uhm. I got a new construction idea. How about investing two pairs of 10" woofers and stack them with W18 - Esotar combo in WMTMW configuration? Both 10" and W18 in acoustic resistance cabinets. Can't play that deep but for example 60-80Hz extension would be pretty good, it's easy to take the rest with single monopolesubwoofer (like BMS 18N850).
I've also considered single monopole sub pretty necessary to the system if I like to expand the system for multichannel later and there just isn't replacement for a heavy closed/vented bass when it comes to LFE. Why not use it with some of the mains bass as well...
At least the WMTMW configuration seems to work and it has pretty smooth directivity at vertical axis.
Jussi
I've also considered single monopole sub pretty necessary to the system if I like to expand the system for multichannel later and there just isn't replacement for a heavy closed/vented bass when it comes to LFE. Why not use it with some of the mains bass as well...
At least the WMTMW configuration seems to work and it has pretty smooth directivity at vertical axis.
Jussi
Member
Joined 2003
An externally hosted image should be here but it was not working when we last tested it.
Jussi,
Here is the BMS 18N850 in a 15" U-baffle...just tested for a few minutes this afternoon. Baffle is 3" thick with 1.5" walls, so it is fairly heavy to keep it from "walking".
There is a little huffing near X-max, but not bad because the aerodynamic design of the pole vent seems incredibly effective. So far, I was wrong about using a "silencer" on the pole...noise actually increases with anything near the vent. Inserting two fingers in the vent makes noise quite noticeable but I doubt I will be able to hear it in normal operation.
The symetrical configuration you mention (like WMTMW) is my favorite because image and soundstage are so stable...I don't think any conventional layout can beat them in that regard. I would continue to build them except I need to have something smaller this time...or at least not so tall.
Paul
Paul W said:
Looks great! Let me know how it sounds when you get it tuned.
What kind of mains do you have? Looks like a Excel + ribbon design in the backround.
It seems like I won't have enough space to play with dipole bass. I have to place the speakers along the long side of the room. This gives more space to sides but doesn't allow decent positions for dipole bass. Turning listening direction 90 degrees would improve this but watching TV from 5m+ away just doesn't work.
So it seems like I have to make a compromisse with the bass department. Compromisses compromisses. WMTMW or even Dynaudio Evidence Master like WWMTMWW has crossed my mind. Both could be done with 10" woofers and have acoustic resistance on them but I'm not that convinced of AR solution in the bass range. Sure it could work, even resistance could be linear (enough) but does it still sound good. I don't give a heck about measurements if the sound sucks.
One possibilty is using 2x10" in WMTMW and have AR on them but that requires a subwoofer to assist. This would suit my thoughts for HT use later but according to my experience steep cross at such low crossover frequency doesn't do good in overall timing of the system. It seems like bass is just dragging behind a bit.
So it seems like the strongest candidate is the 2x8-10" variation of WMTMW with closed woofers, AR mids and waveguided treble or larger setup with four 8" on each side in WWMTMWW Evidence type configuration. According to my simulations for example 2nd order 200Hz cross should give pretty nice vertical polar pattern. Naturally this messes up some of the horizontal directivity provided by the AR midsolution but I don't know how to dodge that. Naturally at least the bass section has to be with active filters, perhaps the whole deal.
With rather large WWMTMWW config it's possible to get rid from couple worst floor reflections around 250Hz and 500Hz. I thought to use Seas standard models or Peerless HDS for such system. Both have 8" models that fit into small closed cabinet. Perhaps the Nomex cone HDS is the stronger at this point. Less linear excursion than for example Seas new CD22 but whole lot less mms, a bit more efficiency and a lot lower inductance. Naturally they need a bit boost at the bottom if 20Hz extension is required. Personally I'd prefer boosting a bit before using a well extended vented solution and have to knock of some from a large frequencyband.
Perhaps the other option could be 2x8" in a vented cabinet. A friend of mine is selling two pairs of 21W/8555-00 Scan Speaks and they seem to fit very well into 105-110 litres 22Hz tuned vented environment. F6 around 6dB and xmax pretty same than four 8":ers in closed cabinet. Or at least in the bottom end, I don't know is "being loud enough" a problem anymore above 50Hz or so...
But is there a difference in nature between vented and closed bass? 8" Nomex in 15 litres cabinet needs boost and compared to it's displacement capacity cabinet is pretty small, does this cause "suffication" effect etc? At least 21W/8555-00 in 52-55 litres 22Hz each is pretty much schoolbook cabinet, I guess it can't be much better than that. At least SS drivers need very low tuning frequency, they have very low loss suspensions and it's a risk to allow them play frequences below their tuning. 22Hz should be pretty safe in music material.
One option is also use 25W/8565-01 woofers in similar size closed cabinet WMTMW config. Would make a bit like Confidence C4 look system. This also makes propably most versatile system since 25W:s can be used in AR cabinet if closed system just doesn't work. But it still requires the sub (at least for the bottom octave).
What do you think?
Jussi
Actually that 52-55 litres space for each woofer isn't that easy to arrange. With slim cabinet I'd estimate 32-36 litres on top and bottom is more realistic. This would suggest four HDS Peerless units on each speaker with decent 0,7 or so Qtc value.
Expanding the system for 10" woofers also widens the cabinet but still 0,7 Q for 25W isn't easy to reach. Allthought I'm not so convinced how actual Qtc effects on the sound. Response shape itself is easy to adjust, there are Linkwitz transforms and other gadgeds to do it. I'd be more intrested in cabinet volume compared to drivers displacement. For extreme example Peerless XLS 10" fits into 5-6 litres closed cabinet and has Qtc 0,7. But such small space suffers from pretty dramatical pressure changes during high excursions that driver is capable. This also stresses the driver and increases distorsion and compression.
Darn that Evidence Master looks cooool. Just like that. Magnesium Excels for mids, nice gray shining metal color on the midbaffle, same paint for woofers flange, nice vaneers... 🙄
Overally those Dynaudio concepts are pretty smart. They use modules in them. Easy to stack and in DIY application it allows to change blocks without building the whole thing all over again.
Jussi
Expanding the system for 10" woofers also widens the cabinet but still 0,7 Q for 25W isn't easy to reach. Allthought I'm not so convinced how actual Qtc effects on the sound. Response shape itself is easy to adjust, there are Linkwitz transforms and other gadgeds to do it. I'd be more intrested in cabinet volume compared to drivers displacement. For extreme example Peerless XLS 10" fits into 5-6 litres closed cabinet and has Qtc 0,7. But such small space suffers from pretty dramatical pressure changes during high excursions that driver is capable. This also stresses the driver and increases distorsion and compression.
Darn that Evidence Master looks cooool. Just like that. Magnesium Excels for mids, nice gray shining metal color on the midbaffle, same paint for woofers flange, nice vaneers... 🙄
Overally those Dynaudio concepts are pretty smart. They use modules in them. Easy to stack and in DIY application it allows to change blocks without building the whole thing all over again.
Jussi
Member
Joined 2003
Jussi,
You have too many good combinations on your mind! I think rapid protyping modules is the way to go. In other words, build MTM with several separate woofer modules just for trials and then build final (finished) version after you decide which you like the best. Personally, I'd try a 4-10" dipole/AR versions first, followed by sealed...not vented. Even with 4-10" AR/dipole per side you'll probably want a sub.
Modular approach is what I decided to do except my puzzle is on the top end...I think my woofer section is stable, but upper octaves are not. (I am trying to get same SQ as WTW ribbon in a smaller/shorter package.) There are at least 5 possiblities for me so I decided to build quick test baffles to place on top of woofer module...probably not even painted for 1st round.
Here are the current mains you asked about...yup Excel + ribbon. In previous post, Seas W26 does look very small behind 18N850!
Paul
You have too many good combinations on your mind! I think rapid protyping modules is the way to go. In other words, build MTM with several separate woofer modules just for trials and then build final (finished) version after you decide which you like the best. Personally, I'd try a 4-10" dipole/AR versions first, followed by sealed...not vented. Even with 4-10" AR/dipole per side you'll probably want a sub.
Modular approach is what I decided to do except my puzzle is on the top end...I think my woofer section is stable, but upper octaves are not. (I am trying to get same SQ as WTW ribbon in a smaller/shorter package.) There are at least 5 possiblities for me so I decided to build quick test baffles to place on top of woofer module...probably not even painted for 1st round.
Here are the current mains you asked about...yup Excel + ribbon. In previous post, Seas W26 does look very small behind 18N850!
Paul
An externally hosted image should be here but it was not working when we last tested it.
Nice work!
I saw your name on a google search and thought I'd say "hello".
I went to Koss, then formed Sound Associates and developed the Enigma Dipole Subwoofer and ZSE-380 which we sold to Mitek and then went to Bose in MA and they moved me out here to San Diego. Still designing...but transducers now for Home, OEM and some Pro.
I remarried 3 years ago and have 14 month old twins. Pretty much a second life!
What's up with you?
John Bruss
misterears@sbcglobal.net
I saw your name on a google search and thought I'd say "hello".
I went to Koss, then formed Sound Associates and developed the Enigma Dipole Subwoofer and ZSE-380 which we sold to Mitek and then went to Bose in MA and they moved me out here to San Diego. Still designing...but transducers now for Home, OEM and some Pro.
I remarried 3 years ago and have 14 month old twins. Pretty much a second life!
What's up with you?
John Bruss
misterears@sbcglobal.net
Member
Joined 2003
Hey John!
Wow...it's been 30 years!
Our PC business eventually transfered me to Chicago where I later worked for a couple of large communications/networking companies. Just over 7 years ago I moved to the east coast to work for a Japanese printer manufacturer which is where I am now.
I just restarted the speaker building hobby a few years ago and have run into guys asking about a couple of your designs...I think AS-1373 and AS-1348 were the model numbers.
Congrats on the "second life". Drop me a PM if you'd like email addresses for a couple of the guys we used to work with.
Great to hear from you!
Paul
pnwright3@yahoo.com
Wow...it's been 30 years!
Our PC business eventually transfered me to Chicago where I later worked for a couple of large communications/networking companies. Just over 7 years ago I moved to the east coast to work for a Japanese printer manufacturer which is where I am now.
I just restarted the speaker building hobby a few years ago and have run into guys asking about a couple of your designs...I think AS-1373 and AS-1348 were the model numbers.
Congrats on the "second life". Drop me a PM if you'd like email addresses for a couple of the guys we used to work with.
Great to hear from you!
Paul
pnwright3@yahoo.com
Paul,
What do you think, is BMS Pro quiet enough for full linear excursion dipole application?
Propably the least compromissed solution is to put 25W Scans playing from 60-80Hz up to 300Hz or so, use AR on them as well and have heavy duty sub for LFE and mains lowbass. Naturally this is also the most expensive and complicated. 😀
Jussi
What do you think, is BMS Pro quiet enough for full linear excursion dipole application?
Propably the least compromissed solution is to put 25W Scans playing from 60-80Hz up to 300Hz or so, use AR on them as well and have heavy duty sub for LFE and mains lowbass. Naturally this is also the most expensive and complicated. 😀
Jussi
Member
Joined 2003
Jussi,
Haven't listened to the BMS at all since last report so no new impressions. (Listening to woofers is pretty boring!) Not sure (either way) about full dipole operation but I am 100% confident they will work for AR because AR low-pass filter will attenuate any small noise.
As a starting point, wool felt approximately 7mm thick will be applied in layers near the rear of U-baffle. I found natural fibers like cotton and true wool work well for AR...better than synthetic materials I have tried. Synthetic fibers are usually smooth and slick while real wool has "scales" on individual fibers and cotton has "leaves" like ear of corn on individual fibers. (I used 100% cotton rug material on a midrange a few months ago and it worked really well.) I think natural fibers tend to grab air trying to pass...but I need to do more reading.
My spare time has been spent building the first two pairs of "lab rat" HF modules. I decided any fair trial would require time in living area, so I did paint them. One pair is normal W22 dipole with Dayton RS52 dome mid and MB Quart tweeter. Second pair is W22 with very cheap coax just to try coax (though the more I look at these Insignia drivers the more I think they may be TOO cheap to judge character of coax). I hope to start collecting measurements this weekend but I need to go to Japan next week so it will be a while before I get crossovers working.
Your 25W SS solution should work very well if you use at least 2 per side. Are you still planning the WMTMW configuration? The only suggestion I have is to try to place the subs as close, or even a little closer to your listening position than the mains. If you have to use delay, I believe it is better to add delay to subs than to mains.
Paul
Haven't listened to the BMS at all since last report so no new impressions. (Listening to woofers is pretty boring!) Not sure (either way) about full dipole operation but I am 100% confident they will work for AR because AR low-pass filter will attenuate any small noise.
As a starting point, wool felt approximately 7mm thick will be applied in layers near the rear of U-baffle. I found natural fibers like cotton and true wool work well for AR...better than synthetic materials I have tried. Synthetic fibers are usually smooth and slick while real wool has "scales" on individual fibers and cotton has "leaves" like ear of corn on individual fibers. (I used 100% cotton rug material on a midrange a few months ago and it worked really well.) I think natural fibers tend to grab air trying to pass...but I need to do more reading.
My spare time has been spent building the first two pairs of "lab rat" HF modules. I decided any fair trial would require time in living area, so I did paint them. One pair is normal W22 dipole with Dayton RS52 dome mid and MB Quart tweeter. Second pair is W22 with very cheap coax just to try coax (though the more I look at these Insignia drivers the more I think they may be TOO cheap to judge character of coax). I hope to start collecting measurements this weekend but I need to go to Japan next week so it will be a while before I get crossovers working.
An externally hosted image should be here but it was not working when we last tested it.
Your 25W SS solution should work very well if you use at least 2 per side. Are you still planning the WMTMW configuration? The only suggestion I have is to try to place the subs as close, or even a little closer to your listening position than the mains. If you have to use delay, I believe it is better to add delay to subs than to mains.
Paul
Paul,
Intresting prototypes. Funny how huge that BMS looks compared to those tiny W22 mids. 🙂
I guess that WMTMW with 25W Scans, W18E Seas and Esotars should do the trick down to 60-80Hz or so in AR cabinets. But this option requires sub or two for the lowbass and LFE. Propably the "best" configuration but also the most expensive and complicated one.
Jussi
Intresting prototypes. Funny how huge that BMS looks compared to those tiny W22 mids. 🙂
I guess that WMTMW with 25W Scans, W18E Seas and Esotars should do the trick down to 60-80Hz or so in AR cabinets. But this option requires sub or two for the lowbass and LFE. Propably the "best" configuration but also the most expensive and complicated one.
Jussi
Attn. Mr.Ears John Bruss
Misterears , I have emailed you a few times with no luck , I am a new audiophile and need some help . I have a pair of Mitek ZSE 380 speakers! I opened the Equalizer and found a socket with 8 or so pins.... what goes here? I'm so amazed with your fun design and work , I want to get more out of these speakers, what does the socket do?
Misterears , I have emailed you a few times with no luck , I am a new audiophile and need some help . I have a pair of Mitek ZSE 380 speakers! I opened the Equalizer and found a socket with 8 or so pins.... what goes here? I'm so amazed with your fun design and work , I want to get more out of these speakers, what does the socket do?
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