I thought I would post a few pics from the president's blog showing some details of the handmade Japanese paper used in the main cones:
One reason for the toughness of the paper is the tightly and randomly interlocked mulberry fibers.
The fibers don't have any consistency in their orientation (except that they are lying flat in the plane of the sheet, of course) -- they are consistently random and tightly interlinked.
With considerable effort, the paper can be torn. When torn, the volume at the tear expands to 20 times the volume of the paper. That's not like any other paper I've seen.
At 400X magnification, the fibers are seen to be of a wide range of sizes averaging around 15 microns in diameter. If you pull the fibers right out of the paper, they turn into a fluff of near-nothingness that floats gently in the air.
"Tough fluff."
An externally hosted image should be here but it was not working when we last tested it.
One reason for the toughness of the paper is the tightly and randomly interlocked mulberry fibers.
An externally hosted image should be here but it was not working when we last tested it.
The fibers don't have any consistency in their orientation (except that they are lying flat in the plane of the sheet, of course) -- they are consistently random and tightly interlinked.
An externally hosted image should be here but it was not working when we last tested it.
With considerable effort, the paper can be torn. When torn, the volume at the tear expands to 20 times the volume of the paper. That's not like any other paper I've seen.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
At 400X magnification, the fibers are seen to be of a wide range of sizes averaging around 15 microns in diameter. If you pull the fibers right out of the paper, they turn into a fluff of near-nothingness that floats gently in the air.
"Tough fluff."
Hi Chris,
Thanks for the pics and info... most interesting fluff. How does this compare to the paper used on the whizzer cone? Similar?
Regards, KM
Thanks for the pics and info... most interesting fluff. How does this compare to the paper used on the whizzer cone? Similar?
Regards, KM
The paper used in the whizzer cones is also handmade Japanese paper of the highest quality, but it is made from completely different raw materials, and it is made by a different craftsman.
-- Chris
-- Chris
The whizzer paper is highly compressed, quite thin, (and for all you users out there, preferably not touched any more than necessary...).
If a fingernail is scratched against clean-cut edges of a piece of the paper used in the whizzer and a piece of the paper used in the main cone, one can hear the two types of paper being able to producing sounds in two very different sets of frequencies. This seems to help give a more pleasant acoustic crossover between main cone and subcone. I suspect that the two materials are each helping to achieve a better overall tonal balance in combination with the other paper. This is just a theory I have hit upon as I have been carefully observing the materials and how they go together, and listen to the results. There must have been an incredibly lengthy process of trial and error to achieve such effective results. Who knows, perhaps there might be a way of developing drivers like these more quickly through computer modeling, but to my knowledge nobody has done so yet, and judging from the sound quality of the end results with Feastrex, I'm inclined to think that perhaps the best "theory" to apply to cone design and refinement is to just keep building and listening and rebuilding in a process of continual refinement. In other words, when getting down to the nitty gritty (ursula 1000) of designing full range drivers, there is no free lunch! A lot of time had to be invested (and lets not forget the large quantities of expensive paper that had to be used) in order to finally arrive at the sound of the drivers now that finally achieve the status of commercial products.
I personally think that alot of full rangers on the market would sound alot better if more attention was paid to the finer points of the the acoustic crossover. Looking back on the various Fostex drivers that I have worked with, it seems that their whizzers tend to have have a much more restrained response in the HF compared with Feastrex drivers, excepting the on axis response. (which also happens to look "pretty" when graphed...). While they do sound nice on axis, I always felt that especially the big ones can develop a "shout" when listened to off-axis, because the 2-3kHz region remains intact while the HF response falls off so dramatically, even in the first 5 degrees, that a peak results (typically at 2-3k).
It seems that in many full rangers by design that the whizzer response level is "detuned" from what a typical HiFi speaker "should" be because if it were to try to fill the room with nice off axis HF resp, then the whizzer would have many more interactions with the main cone at lower frequencies (than it already does). Negotiating the trade-offs here is very hard work, but listening to Feastrex, it certainly seems like a viable solution to this long standing problem has been realized.
-Clark
If a fingernail is scratched against clean-cut edges of a piece of the paper used in the whizzer and a piece of the paper used in the main cone, one can hear the two types of paper being able to producing sounds in two very different sets of frequencies. This seems to help give a more pleasant acoustic crossover between main cone and subcone. I suspect that the two materials are each helping to achieve a better overall tonal balance in combination with the other paper. This is just a theory I have hit upon as I have been carefully observing the materials and how they go together, and listen to the results. There must have been an incredibly lengthy process of trial and error to achieve such effective results. Who knows, perhaps there might be a way of developing drivers like these more quickly through computer modeling, but to my knowledge nobody has done so yet, and judging from the sound quality of the end results with Feastrex, I'm inclined to think that perhaps the best "theory" to apply to cone design and refinement is to just keep building and listening and rebuilding in a process of continual refinement. In other words, when getting down to the nitty gritty (ursula 1000) of designing full range drivers, there is no free lunch! A lot of time had to be invested (and lets not forget the large quantities of expensive paper that had to be used) in order to finally arrive at the sound of the drivers now that finally achieve the status of commercial products.
I personally think that alot of full rangers on the market would sound alot better if more attention was paid to the finer points of the the acoustic crossover. Looking back on the various Fostex drivers that I have worked with, it seems that their whizzers tend to have have a much more restrained response in the HF compared with Feastrex drivers, excepting the on axis response. (which also happens to look "pretty" when graphed...). While they do sound nice on axis, I always felt that especially the big ones can develop a "shout" when listened to off-axis, because the 2-3kHz region remains intact while the HF response falls off so dramatically, even in the first 5 degrees, that a peak results (typically at 2-3k).
It seems that in many full rangers by design that the whizzer response level is "detuned" from what a typical HiFi speaker "should" be because if it were to try to fill the room with nice off axis HF resp, then the whizzer would have many more interactions with the main cone at lower frequencies (than it already does). Negotiating the trade-offs here is very hard work, but listening to Feastrex, it certainly seems like a viable solution to this long standing problem has been realized.
-Clark
Speaking of whizzers, btw, yesterday I totally met my match during this trial driver making process I have been on for the last few weeks. After me fumbling like an idiot for 30 seconds or so trying to attach the whizzer, which is the final, probably the most difficult and most important stage of construction for the sonics, Mr. Teramoto had to step in (very quickly) and masterfully get it into the right position before the glue started to set up. Luckily everything turned out ok, listening to the drivers right now and they sound fine. (Well, everyone says they sound fine, but I can hear just ever so slightly what might be the timidness of my beginner's hand in their sound and it drives me nuts!) But anyways, Wheew! Building like this is huge motivation for me to refine my technique and learn as much as I can as well as I can. It is addictive...and incredibly humbling work.
-Clark
-Clark
Why not just leave the whizzer cone off?🙂 I'd like to try the 9" version if I could get one with a normal well-damped dust cover.
John
John
The driver functions as an organic unit, with the whizzer cone coming into play at a fairly low frequency. The whole driver would need to be completely redesigned if the whizzer was left off and a dust cap provided instead of a phase plug.
-- Chris
P.S. Mr. Teramoto wants to make the drivers that customers want to buy, as long as they are fullrange drivers. It's sort of like the Ford Model T -- you can have it in any color you like, as long as it's black. 😉 Seriously, he says "I don't do tweeters or woofers; life's too short for me to spread myself out like that," and thinks that any wide band or midrange driver worth its salt ought to be working well enough over a large enough band to merit the name "fullrange driver." In his view, if it doesn't do that, it isn't what he would consider to be a good driver. Just so you know where he's coming from . . .
-- Chris
P.S. Mr. Teramoto wants to make the drivers that customers want to buy, as long as they are fullrange drivers. It's sort of like the Ford Model T -- you can have it in any color you like, as long as it's black. 😉 Seriously, he says "I don't do tweeters or woofers; life's too short for me to spread myself out like that," and thinks that any wide band or midrange driver worth its salt ought to be working well enough over a large enough band to merit the name "fullrange driver." In his view, if it doesn't do that, it isn't what he would consider to be a good driver. Just so you know where he's coming from . . .
The reason I say that is the only decent-sounding Lowther I've ever heard had the whizzer cone removed by Tommy Horning on his Pericles speaker. And Mr. Teramoto's predecessor made speakers without whizzer cones (with solid gold dustcaps, no less). As much as I love the Feastrex drivers, I still believe they exhibit a common problem with other drivers featuring whizzers, namely audible intermodulation distortion.
John
John
If by Mr. Teramoto's predecessor you are referring to Takashi Sano (of the defunct Exact brand), he never made any drivers without whizzer cones that I can recall. By the way, those gold dust caps had a definite tendency to self destruct probably due to the physical properties of the gold used, and also to the fact that they were attached to the whizzer cone. Any flexing of the whizzer cone during use would tend to cause the gold dust cap to flex, eventually destroying it. Mr. Teramoto made (and still makes, for an OEM customer) drivers with metal dust caps; these have the dust cap attached directly to the voice coil former rather than to the whizzer cone, and none of the problems characteristic of Mr. Sano's gold dust caps have been experienced.
-- Chris
-- Chris
jlsem said:
I have examples of Lowthers without whizzers, and I don't like them nearly
as much. They make great midrange drivers after you filter out the peak,
though.
😎
"They're here!" Permendurgeist
Feastrex has produced a pair of D9e-III drivers (standard cast aluminum baskets) that will be going to Russia, and they will be running them in by playing them in their head office listening room until September 15. I was just just talking to Clark Blumenstein on the phone about the his first two days of listening to these drivers. I swear he sounds like a guy who has been ingesting magic mushrooms or something. 😀 It is actually quite humorous to talk to Clark about this listening experience. He is totally serious but he really comes across sounding like someone trying to describe a mystical experience resulting from the use of a mind-altering substance. It's even funnier because normally he is very good at articulating what he hears, but this time, he seems to be at a loss for words. In our conversation, he didn't even bother trying to describe the sound coming off the drivers; he thought it would be almost impossible for him to describe the sound in a way that would give me an accurate appreciation for what they sound like. (Apparently, they really need to be heard to be understood.) Instead, he focused on trying to give me an inkling of the impact that the listening experience has had on him. When people start using expressions like "It feels like the entire weight of the universe is concentrated on the tip of a needle," you know you're dealing with something quite out of the ordinary. 😀 One of the most helpful things he said to me was that it's not a step UP the ladder from the D9e-II drivers, but rather, a step OFF the ladder . . . you're no longer listening to music; rather, the music simply "is." Clark has been throwing all kinds of music at them for the past two days and he says they present everything superbly. He said "this is the happiest sound I have ever heard . . . the smile has not disappeared from my face during the past two days."
Now Clark finally understands why Mr. Teramoto and Mr. Akiyama are a little bit crazy in the head. After listening to these drivers, apparently nobody can be "normal" any more.
That's just the 9-inch field coil drivers. Mr. Tanaka, the urushi lacquer craftsman from Kyoto, has just brought up some gorgeously finished prototype enclosures for the equally wonderful 5-inch drivers; Clark told me he thinks these latest enclosures are a great success, both visually and sonically. I'll try to post pics if I can obtain any, but I think their shape is basically like the enclosures in the photo above that have the "chimney" coming out the top.
-- Chris
Feastrex has produced a pair of D9e-III drivers (standard cast aluminum baskets) that will be going to Russia, and they will be running them in by playing them in their head office listening room until September 15. I was just just talking to Clark Blumenstein on the phone about the his first two days of listening to these drivers. I swear he sounds like a guy who has been ingesting magic mushrooms or something. 😀 It is actually quite humorous to talk to Clark about this listening experience. He is totally serious but he really comes across sounding like someone trying to describe a mystical experience resulting from the use of a mind-altering substance. It's even funnier because normally he is very good at articulating what he hears, but this time, he seems to be at a loss for words. In our conversation, he didn't even bother trying to describe the sound coming off the drivers; he thought it would be almost impossible for him to describe the sound in a way that would give me an accurate appreciation for what they sound like. (Apparently, they really need to be heard to be understood.) Instead, he focused on trying to give me an inkling of the impact that the listening experience has had on him. When people start using expressions like "It feels like the entire weight of the universe is concentrated on the tip of a needle," you know you're dealing with something quite out of the ordinary. 😀 One of the most helpful things he said to me was that it's not a step UP the ladder from the D9e-II drivers, but rather, a step OFF the ladder . . . you're no longer listening to music; rather, the music simply "is." Clark has been throwing all kinds of music at them for the past two days and he says they present everything superbly. He said "this is the happiest sound I have ever heard . . . the smile has not disappeared from my face during the past two days."
Now Clark finally understands why Mr. Teramoto and Mr. Akiyama are a little bit crazy in the head. After listening to these drivers, apparently nobody can be "normal" any more.
That's just the 9-inch field coil drivers. Mr. Tanaka, the urushi lacquer craftsman from Kyoto, has just brought up some gorgeously finished prototype enclosures for the equally wonderful 5-inch drivers; Clark told me he thinks these latest enclosures are a great success, both visually and sonically. I'll try to post pics if I can obtain any, but I think their shape is basically like the enclosures in the photo above that have the "chimney" coming out the top.
-- Chris
I feel very happy that I live in Japan.
Today, I got a confirmation e-mail from Dr. Akiyama. My demo request was accepted. I will visit their listening room on the afternoon of September 4th. I will post my report after that.
I really "listen forward" to tasting the "feast".
Today, I got a confirmation e-mail from Dr. Akiyama. My demo request was accepted. I will visit their listening room on the afternoon of September 4th. I will post my report after that.
I really "listen forward" to tasting the "feast".
These 5-inch driver enclosures are made of Douglas Fir and finished with Japanese urushi lacquer inside and out. These enclosures (or a pair very similar) will be among the items demonstrated by Feastrex at RMAF.
-- Chris
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
-- Chris
What
Can you talk about those cabs? They look like they are two different cabs...
Sizes. etc
Phil
Santa Fe
Can you talk about those cabs? They look like they are two different cabs...
Sizes. etc
Phil
Santa Fe
That's pretty. I imagine it's a Nessie variation. Basically, a ruddy great big folded resonance tube. As a ROT, they're made of two pipes, the driver being mounted at the sealed end of the shorter one, which is of about 2/3 the CSA of the larger one to the rear. Like this:
Attachments
Re: "They're here!" Permendurgeist
I'm neither a professional critic nor an industry observer. Even for a just an amateur like me, the breakthrough the product had established in a history of full range units was apparent. Superb resolution in a high range is far beyond the conventional standard level for full range. If you were exposed as blind with an eye-mask, you might identify the sound being generated by a tweeter or a super tweeter. However, actually there you find only a full�@range unit with paper cones of 9" diameter.
I could perceive a lot of new details in a musical performance. Especially the unit has an unbelievable capability of reproducing tones emitted by metal musical instruments such as cymbals as well as percussion instruments that contain highly transient components. The sound reminded me of the fact again that a piano or cembalo sound is produced by steel wires.
The units are set in existing enclosures shown in the pictures posted by Chris. I felt a balancing of the low range against mid and high was not pursued enough for the current enclosure setting. Obtaining an adequate low range performance from this unit might be a responsibility of an enclosure designer rather than a unit designer.
I could enjoy the 9" Exciter with Permendur Core (Type III) this afternoon.cdwitmer said:
I'm neither a professional critic nor an industry observer. Even for a just an amateur like me, the breakthrough the product had established in a history of full range units was apparent. Superb resolution in a high range is far beyond the conventional standard level for full range. If you were exposed as blind with an eye-mask, you might identify the sound being generated by a tweeter or a super tweeter. However, actually there you find only a full�@range unit with paper cones of 9" diameter.
I could perceive a lot of new details in a musical performance. Especially the unit has an unbelievable capability of reproducing tones emitted by metal musical instruments such as cymbals as well as percussion instruments that contain highly transient components. The sound reminded me of the fact again that a piano or cembalo sound is produced by steel wires.
The units are set in existing enclosures shown in the pictures posted by Chris. I felt a balancing of the low range against mid and high was not pursued enough for the current enclosure setting. Obtaining an adequate low range performance from this unit might be a responsibility of an enclosure designer rather than a unit designer.
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