Just thought I'd share...
Not really, still working on the front / back horns but that will take some time. The complexity of this particular design intrigues me most and it befits best the "challenge" put before me.
Otherwise I'm merely keeping everyone posted as to the different feedback I'm receiving from people who's opinions and skills I respect. Feel free to ignore it, them, or the entire thread...
The Nagaoka's will be worth building whatever the outcome of my front / back horn design is. As much as the complexity of the front / back horns intrigue me, so does the simplicity of the Nagaoka.
serenechaos said:
Not really, still working on the front / back horns but that will take some time. The complexity of this particular design intrigues me most and it befits best the "challenge" put before me.
Otherwise I'm merely keeping everyone posted as to the different feedback I'm receiving from people who's opinions and skills I respect. Feel free to ignore it, them, or the entire thread...
The Nagaoka's will be worth building whatever the outcome of my front / back horn design is. As much as the complexity of the front / back horns intrigue me, so does the simplicity of the Nagaoka.
adaptation of sachiko ?
I would be very interested to see (and maybe to build) a nagaoka style enclosure for lowther.
I suppose many other regular readers of this forum would be pleased too ( as I presume from the various request concerning the possibility to use the sachiko with lowther)
Regards,
I would be very interested to see (and maybe to build) a nagaoka style enclosure for lowther.
I suppose many other regular readers of this forum would be pleased too ( as I presume from the various request concerning the possibility to use the sachiko with lowther)
Regards,
Re: Advice from Lowther...
Companies like this deserve all the custom they can get.
Now that is what "service" is all about.Ronmeister said:...............it's useful to contact the factory. I did, and similar to hornophile's experience, they answered within a day! ...................
Their advice would be ........................................
They kindly offer to send both units, the PM5 and DX4 for me to try.......
Companies like this deserve all the custom they can get.
Re: The Ultimate Lowther
Bummer, was hoping to swap out DX4's for ticonals in OB, after selling my wife's dog.
My only 2 cents is, I moved from smaller listening room, may 150 sq feet, to 800 sq feet, and front loaded horns didn't do low end well anymore. OB with woofer helps.
Jon Ver Halen said:
Bummer, was hoping to swap out DX4's for ticonals in OB, after selling my wife's dog.
My only 2 cents is, I moved from smaller listening room, may 150 sq feet, to 800 sq feet, and front loaded horns didn't do low end well anymore. OB with woofer helps.
Hi,
I see no one has mentioned the Side Vivace yet? This is an evolved Schmackshorn. The driver has been moved to the side, making for a smaller baffle. Internally, there are lots more reflectors and a helmholtzresonator to smooth out response.
The original Schmacks is the reference for an entire generation of fullrange diyers, providing loud and deep bass response. It had some response anomalies and it went out of style. The Side Vivace is a revision from the late nineties (I think) by the chairman of the Lowther Club of Belgium from the time.
I never heard it, but Bert Doppenberg said it was a very good horn. At the time, big boxes were going out of style very rapidly and I think the Side Vivace never hit it big because of it. When I see the large BIBs and Nagaoka-style horns that are being built now, I think it was a missed opportunity. My personal experiences with the Schmacks are that it is very good and with some tweaking would be excellent/perfect. The Side Vivace seems to be there already.
There a build report here, but no plans.
http://www.geocities.com/agalavotti/lowther1.htm
Wow, a last minute Google for plans and I found this:
http://www.diyaudio.com/forums/showthread.php?postid=1714624#post1714624
Ivo
I see no one has mentioned the Side Vivace yet? This is an evolved Schmackshorn. The driver has been moved to the side, making for a smaller baffle. Internally, there are lots more reflectors and a helmholtzresonator to smooth out response.
The original Schmacks is the reference for an entire generation of fullrange diyers, providing loud and deep bass response. It had some response anomalies and it went out of style. The Side Vivace is a revision from the late nineties (I think) by the chairman of the Lowther Club of Belgium from the time.
I never heard it, but Bert Doppenberg said it was a very good horn. At the time, big boxes were going out of style very rapidly and I think the Side Vivace never hit it big because of it. When I see the large BIBs and Nagaoka-style horns that are being built now, I think it was a missed opportunity. My personal experiences with the Schmacks are that it is very good and with some tweaking would be excellent/perfect. The Side Vivace seems to be there already.
There a build report here, but no plans.
http://www.geocities.com/agalavotti/lowther1.htm
Wow, a last minute Google for plans and I found this:
http://www.diyaudio.com/forums/showthread.php?postid=1714624#post1714624
Ivo
planet10 said:
Scottmoose said:
Thanks Dave & Scott, I'm looking forward to the build. There's a lot of potential for the use of special materials, especially, as you mention in the design, the side panels.
For what it's worth; my suggestion for the name...
I'm not sure of the historical background related to the naming of the Nagaoka style horns. But in keeping with the Japanese nomenclature I'd suggest Shokokuji, reported to be the tallest pagoda (108 Meters) ever built in Japan. It no longer exists, it would have been the tallest wooden building in the world, though only 7 stories.
Attachments
Interesting.
Actually, the Nagaoka bit is a little tenuous, as it was Harry Olson who first came up with the idea, & it was his designs that actually inspired most of mine, especially WRT their configuration. Still, Nagaoka was the man who made the type of construction popular, so hats off to him too.
Actually, the Nagaoka bit is a little tenuous, as it was Harry Olson who first came up with the idea, & it was his designs that actually inspired most of mine, especially WRT their configuration. Still, Nagaoka was the man who made the type of construction popular, so hats off to him too.
Next step...
I was wondering, I remember something about "the Nagaoka coefficient" in coils... not my best subject in College...
Back to the "no-holds-barred" bit of the thread. I'll build a set of these, yet-to-be-named Nagaoka horns using materials I still have in my workshop (the "close encounters of the third kind" approach, start with mashed potatoes, then work your way up). That will help me identify the potential, and identify areas of improvement. I'll have to, at that stage, involve the person I'm building them for to get his thoughts.
In the meantime I'm still working on a BLH-FLH design. The principle idea is best described in one of Jon's posts in this thread where he suggests a Big Fun type back horn combined with a Le Cleac'h type front horn. The BLH should be more refined and well integrated with the front horn for an acoustically as well as esthetically cohesive design.
My slow (at sea) internet speed makes researching online a very lengthy process so any assistance with the back-horn-contour and acoustic cross-over would be much appreciated.
Scottmoose said:Interesting.
Actually, the Nagaoka bit is a little tenuous, as it was Harry Olson who first came up with the idea, & it was his designs that actually inspired most of mine, especially WRT their configuration. Still, Nagaoka was the man who made the type of construction popular, so hats off to him too.
I was wondering, I remember something about "the Nagaoka coefficient" in coils... not my best subject in College...
Back to the "no-holds-barred" bit of the thread. I'll build a set of these, yet-to-be-named Nagaoka horns using materials I still have in my workshop (the "close encounters of the third kind" approach, start with mashed potatoes, then work your way up). That will help me identify the potential, and identify areas of improvement. I'll have to, at that stage, involve the person I'm building them for to get his thoughts.
In the meantime I'm still working on a BLH-FLH design. The principle idea is best described in one of Jon's posts in this thread where he suggests a Big Fun type back horn combined with a Le Cleac'h type front horn. The BLH should be more refined and well integrated with the front horn for an acoustically as well as esthetically cohesive design.
My slow (at sea) internet speed makes researching online a very lengthy process so any assistance with the back-horn-contour and acoustic cross-over would be much appreciated.
dimensions of those "shokokuji" horn ?
1. what about the internal dimensions of those shokokuji double horns ?
Will they be made publicly available like the other planet10/scotmoose designs ?
2. Did you a make a simulation of frequency response ?
3. Do you think this design would be ok with a litte work on compression chamber for other lowther 8 inch drivers ? I still have a pair of pm2a waiting for an enclosure (other than the one I use with EX3 and mauhorn IV)
Thanks !
1. what about the internal dimensions of those shokokuji double horns ?
Will they be made publicly available like the other planet10/scotmoose designs ?
2. Did you a make a simulation of frequency response ?
3. Do you think this design would be ok with a litte work on compression chamber for other lowther 8 inch drivers ? I still have a pair of pm2a waiting for an enclosure (other than the one I use with EX3 and mauhorn IV)
Thanks !
Re: dimensions of those "shokokuji" horn ?
No. These (and 2 others for Festrex D5NF and D9NF (and likely future designs for other big-buck drivers)) will be available to users who make a donation (there is a suggested minimum). These designs were all commisioned, and everyone (the commissioners and Scott & myself) felt that these designs should move into a new paid model something like Bob Brines. It means that we are obliged to give support -- and in the case of Maiko for the D5NF even a redesign (not finished yet, sorry Phil).
dave
hornophile said:
No. These (and 2 others for Festrex D5NF and D9NF (and likely future designs for other big-buck drivers)) will be available to users who make a donation (there is a suggested minimum). These designs were all commisioned, and everyone (the commissioners and Scott & myself) felt that these designs should move into a new paid model something like Bob Brines. It means that we are obliged to give support -- and in the case of Maiko for the D5NF even a redesign (not finished yet, sorry Phil).
dave
Thanks Dave. Pity it got like that. On the up-side, at least it doesn't happen often.
Hmm. I notice that Hornophile's 2nd & 3rd queries got lost in the clag, so to speak, so, briefly,
2/ Yes indeed. After I finish a box design, I always run it through MathCAD, for a graph & to check for errors. I'm wary about posting them at the moment, as we've had problems with them being misinterpreted in the past.
3/ Ideally, it would need more than just work on the low-pass filter chamber; you design the whole thing for a specific driver. However, yes, it should work very well indeed with the PM2a, assuming they're close to the average measurements I got from the factory.
Hmm. I notice that Hornophile's 2nd & 3rd queries got lost in the clag, so to speak, so, briefly,
2/ Yes indeed. After I finish a box design, I always run it through MathCAD, for a graph & to check for errors. I'm wary about posting them at the moment, as we've had problems with them being misinterpreted in the past.
3/ Ideally, it would need more than just work on the low-pass filter chamber; you design the whole thing for a specific driver. However, yes, it should work very well indeed with the PM2a, assuming they're close to the average measurements I got from the factory.
Back to "no holds..."
Glad we're back on track... I suppose my "no-holds-barred" gag did not diffuse the situation...
With regards to the Shokokuji (is it official yet?) horns, the PM4A's have a stand that can be fastened to the bottom of the compression chamber as well as to the supra-baffle. What would be the preferred way to de-couple the driver from the baffle? Or would we de-couple the supra-baffle with silicone instead? Would it be an idea to have the supra-baffle made of some form of stone?
Secondly, with regards to option 2, the Back - Front - Horn, I've asked Martin from Azurahorns if he has any tips for me. I'm having a hard time to find the right theory for designing this particular kind of loudspeaker. Specifically how to balance the front and the back horn to get an even sound.
I'd like to continue on this two-way path, as a result of this thread I've been asked to build both types of design. They'll be "tested" late summer... I'm not sure, but I'm guessing a BBQ as well as a beverage or two will be involved...
Glad we're back on track... I suppose my "no-holds-barred" gag did not diffuse the situation...
With regards to the Shokokuji (is it official yet?) horns, the PM4A's have a stand that can be fastened to the bottom of the compression chamber as well as to the supra-baffle. What would be the preferred way to de-couple the driver from the baffle? Or would we de-couple the supra-baffle with silicone instead? Would it be an idea to have the supra-baffle made of some form of stone?
Secondly, with regards to option 2, the Back - Front - Horn, I've asked Martin from Azurahorns if he has any tips for me. I'm having a hard time to find the right theory for designing this particular kind of loudspeaker. Specifically how to balance the front and the back horn to get an even sound.
I'd like to continue on this two-way path, as a result of this thread I've been asked to build both types of design. They'll be "tested" late summer... I'm not sure, but I'm guessing a BBQ as well as a beverage or two will be involved...
What about the smaller Carfrae, the Little Big Horn?
http://shows.soundstagelive.com/shows/ces2002/stand_carfrae.shtml
http://www.6moons.com/audioreviews/roadtour1/roadtour.html
http://shows.soundstagelive.com/shows/ces2002/stand_carfrae.shtml
http://www.6moons.com/audioreviews/roadtour1/roadtour.html
Personally, I still wouldn't be over-convinced as it's a tractrix contour, which isn't ideal for bass horns (IMHO, although I'm certainly not alone in that).
Ron -don't worry about it mate; disagreements arise from time to time, but life's too short to waste dwelling on such things. The irony is that it was completely unnecessary, as it was all due to a misunderstanding of my last-but-one post, where I was commenting on the origins of horns constructed from an expanding series of straight manifolds. Water under the bridge, as they say.
No official name yet -I've contacted the gentleman who originally comissioned the design & am waiting for him to get back to me with his prefered name.
Yes, you can use the PM4a's supplied stand if you wish. FWIW, my personal preference would be for a holy brace, as seen in some of Dave & my other cabinets -I don't like having too much metal in a cabinet, & the brace would allow the driver to be positioned centrally, should you wish it. BTW, for the sake of interest / accuracy, the rear-chamber is a low-pass filter, not a compression chamber. For (most) BLHs, the room is the compression chamber.
The driver doesn't have to be decoupled from the baffle per-se; it's a double mount, front & rear. A simple gasket should do the trick ~'good enough' to push any issues below the audibility threshold. As for materials, whatever you like; you might notice some audibile changes, although it's unlikely. Me, I'd use a nice quality hardwood of some description, or even (whisper it) fir, pine, spruce or similar, if properly dried & stable.
Compound horns are a PITA to get right, & theory of them is probably better discussed elsewhere so the thread doesn't get too clagged up. Briefly though, not the point of maximum efficiency of the driver & that's what you're aiming to achieve. Boost the frequencies below the driver's mass-corner with the back-horn, then support the region from mass-corner to max-efficiency (or as near as possible) with the front horn.
Ron -don't worry about it mate; disagreements arise from time to time, but life's too short to waste dwelling on such things. The irony is that it was completely unnecessary, as it was all due to a misunderstanding of my last-but-one post, where I was commenting on the origins of horns constructed from an expanding series of straight manifolds. Water under the bridge, as they say.
No official name yet -I've contacted the gentleman who originally comissioned the design & am waiting for him to get back to me with his prefered name.
Yes, you can use the PM4a's supplied stand if you wish. FWIW, my personal preference would be for a holy brace, as seen in some of Dave & my other cabinets -I don't like having too much metal in a cabinet, & the brace would allow the driver to be positioned centrally, should you wish it. BTW, for the sake of interest / accuracy, the rear-chamber is a low-pass filter, not a compression chamber. For (most) BLHs, the room is the compression chamber.
The driver doesn't have to be decoupled from the baffle per-se; it's a double mount, front & rear. A simple gasket should do the trick ~'good enough' to push any issues below the audibility threshold. As for materials, whatever you like; you might notice some audibile changes, although it's unlikely. Me, I'd use a nice quality hardwood of some description, or even (whisper it) fir, pine, spruce or similar, if properly dried & stable.
Compound horns are a PITA to get right, & theory of them is probably better discussed elsewhere so the thread doesn't get too clagged up. Briefly though, not the point of maximum efficiency of the driver & that's what you're aiming to achieve. Boost the frequencies below the driver's mass-corner with the back-horn, then support the region from mass-corner to max-efficiency (or as near as possible) with the front horn.
Hi Ron,
"Secondly, with regards to option 2, the Back - Front - Horn, I've asked Martin from Azurahorns if he has any tips for me. I'm having a hard time to find the right theory for designing this particular kind of loudspeaker. Specifically how to balance the front and the back horn to get an even sound."
Unless you want to make your own mold or make a front horn on a big lathe, you will have to buy a front horn. You may as well buy a front horn and a compression chamber with first round section of back horn from Martin. Round and symmetrical on axis compression chamber and first section of back horn is partly responsible for success of the design.
On the other hand, I made more complicated mold and did the fiberglass work myself, so I know it is doable at home. I posted before on this forum how to make a mold (model) for home made round horn of any shape and size.
To get Back-Front-Horn right, one needs to experiment, which pretty much makes Martin the only expert out there.
Marek
"Secondly, with regards to option 2, the Back - Front - Horn, I've asked Martin from Azurahorns if he has any tips for me. I'm having a hard time to find the right theory for designing this particular kind of loudspeaker. Specifically how to balance the front and the back horn to get an even sound."
Unless you want to make your own mold or make a front horn on a big lathe, you will have to buy a front horn. You may as well buy a front horn and a compression chamber with first round section of back horn from Martin. Round and symmetrical on axis compression chamber and first section of back horn is partly responsible for success of the design.
On the other hand, I made more complicated mold and did the fiberglass work myself, so I know it is doable at home. I posted before on this forum how to make a mold (model) for home made round horn of any shape and size.
To get Back-Front-Horn right, one needs to experiment, which pretty much makes Martin the only expert out there.
Marek