bcherry said:
The surround is the same, that's for sure. Please look at your driver and check to see if there are holes punched in the spider. If that's the case, the spider is more compliant. If not, it is the same as the D5nf. (Punching holes in the spider of the permanent magnet drivers is a no-no because of the need to protect the VC gap from the entry of ferrous [magnetic] particles. However, in the case of the field coil drivers the VC gap is easier to clean of any such particles that might find their way in there.) Please let me know about your spider . . .
bcherry said:
VC gap is 0.9mm
Xmax is +2mm, 0, -2mm (a total of 4mm range of movement)
-- Chris
I had the chance to listen to Phil's stunning red build of the Maikos with D5nf drivers. Oh. My. Gawd.
The sound is perfectly "life-size" and you can walk around "inside" it somehow. The room is just filled with sound. The bass is easy, effortless, perfectly right, and plenty of smack. The oh-so-smooth midrange magic is all there. The sound is sparkly and sweet, and the 3D phenomenon is just a free bonus I guess!
The listener sits right on-axis, drivers at ear height, barely any toe-in, because the driver isn't beamy. I don't think anyone could ever get tired of this sound. I never imagined there was anything this good.
Phil, thank you for the opportunity -- just to have heard it once puts me in a good mood.
The sound is perfectly "life-size" and you can walk around "inside" it somehow. The room is just filled with sound. The bass is easy, effortless, perfectly right, and plenty of smack. The oh-so-smooth midrange magic is all there. The sound is sparkly and sweet, and the 3D phenomenon is just a free bonus I guess!
The listener sits right on-axis, drivers at ear height, barely any toe-in, because the driver isn't beamy. I don't think anyone could ever get tired of this sound. I never imagined there was anything this good.
Phil, thank you for the opportunity -- just to have heard it once puts me in a good mood.
cdwitmer said:
will need to pull out the drivers to take a look at that.
Here are the d5nf and Nf5ex compared:
Nf5ex
Revc= 14.8465 ohms
Fs = 85.2455 Hz
Zmax= 234.0638 ohms
Ro = 58.9493 ohms
F0 = 74.8698 Hz
F1 = 123.4567 Hz
Fmin= 718.4830 Hz
Qms = 6.9664
Qes = 0.4718
Qts = 0.4419
Le = 0.3586 mH @1kHz
XLe = 16.6969 impedance @1kHz
PLe = 7.7562 phase @1kHz
Diam = 105.0000 mm ( 4.1339 in )
ConeArea = 8659.0145 mm^2( 13.4215 in^2)
Vas = 7.1865 L ( 0.2538 ft^3)
BL = 9.2785 N/A
Mms = 5.1079 g
Cms = 682.4293 uM/N
Kms = 1465.3534 N/M
Rms = 0.3927 R mechanical
Efficiency = 0.9096 %
Sensitivity= 95.5885 dB @1W/1m
d5nf
Revc = 14.5706 ohms
Fs = 107.8037 Hz
Zmax = 159.5979 ohms
Qes = 0.6515
Qms = 6.4850
Qts = 0.5920
Le = 0.4430 mH (at 1 kHz)
Diam = 105.0000 mm ( 4.1339 in )
ConeArea = 8659.0145 mm2( 13.4215 in2)
Vas = 5.4951 L ( 0.1941 ft3)
BL = 7.9544 N/A
Mms = 4.1769 g
Cms = 521.8188 uM/N
Kms = 1916.3741 N/M
Rms = 0.4363 R mechanical
the differences of electrical characteristics would be expected with the two different motors but it seems the mass of cone assembly has gone from Mms = 4.1769 g to Mms = 5.1079 g in the field coil which would lower the Fs.
is there something different between the cone assemblies of the two versions? also, anyone know, based on experience, if increasing mass by about 1 g (about 20%) would lower the Fs by 20 Hz?
regards
Brian
bcherry said:
Well, I know he uses the "added weight method" (rather than an actual enclosure) to measure the parameters, and I know he added more weight than is ideal this time (you can still get ballpark figures even when the added weight is off), so perhaps that accounts for the weight difference . . .
???
???-- Chris
Re: Reply to question on D5e-II with small amplifiers
My friend who uses the WE205D says: "NO PROBLEMO"
"The better the driver, the more of a challenge it poses to the amplifier, in a certain sense -- and it's not just a question of the amount of power available. The drivers will tend to pose more of a challenge to the entire system. -- The D5e-II would be even more revealing. A user might find himself taking a fine-tooth comb to go back over other equipment in the chain one device at a time, checking every single cap, op-amp, etc. "
Dear Chris
Thank you. I am looking forward to mine and praying hard that my amp will be perfect match to the feastrex.
Fine-tuning is always a painful process but hopefully it will be fun
and enjoyable with the D5e-II.
cdwitmer said:
My friend who uses the WE205D says: "NO PROBLEMO"
"The better the driver, the more of a challenge it poses to the amplifier, in a certain sense -- and it's not just a question of the amount of power available. The drivers will tend to pose more of a challenge to the entire system. -- The D5e-II would be even more revealing. A user might find himself taking a fine-tooth comb to go back over other equipment in the chain one device at a time, checking every single cap, op-amp, etc. "
Dear Chris
Thank you. I am looking forward to mine and praying hard that my amp will be perfect match to the feastrex.
Fine-tuning is always a painful process but hopefully it will be fun
and enjoyable with the D5e-II.
the many faces of bamboo
hi Chris:
just came back from the wood factory and asked the owner about the story on bamboo. He said processing and using solid bamboo wood's began in Japan, then later in Taiwan and now in China. the factory he buys from is actually Taiwanese. Bamboo wood for furniture is graded AA, A, and B. AA is what you see in the snap here and is the superior grade with no separations or flaws. The nice thing about bamboo is it can be harvested every four years.
Staining: he said yes, most difficult stain. They use a process of hot staining where they heat up the wood and apply the stain under pressure. I don't know what kind of machinery they have for that but I'll surely take some pictures if I see it in operation.
In two weeks I should have a 30 L cabinet made out of the same kind of what you see in this picture.
DD
not yet. Our high-voltage DC supplies just arrived so as soon as we can all install them will test. that allows me to run the field coil's at the recommended 15 V. Right now they are at 13.5 V and even so seem a little more efficient.
Regards
Brian
chrisb said:
hi Chris:
just came back from the wood factory and asked the owner about the story on bamboo. He said processing and using solid bamboo wood's began in Japan, then later in Taiwan and now in China. the factory he buys from is actually Taiwanese. Bamboo wood for furniture is graded AA, A, and B. AA is what you see in the snap here and is the superior grade with no separations or flaws. The nice thing about bamboo is it can be harvested every four years.
Staining: he said yes, most difficult stain. They use a process of hot staining where they heat up the wood and apply the stain under pressure. I don't know what kind of machinery they have for that but I'll surely take some pictures if I see it in operation.
In two weeks I should have a 30 L cabinet made out of the same kind of what you see in this picture.
DD
not yet. Our high-voltage DC supplies just arrived so as soon as we can all install them will test. that allows me to run the field coil's at the recommended 15 V. Right now they are at 13.5 V and even so seem a little more efficient.
Regards
Brian
Attachments
Hi Talawalla,
Do you think Feastrex drivers will require alignment after a while? Or other periodic maintenance? Or other services that Feastrex owners will need a few years after purchase? I'm sure sensible people will want a solid relationship with the authorized dealer, similar to what Lowther customers rely on. I can't wait to hear what the new lower prices will be!
Do you think Feastrex drivers will require alignment after a while? Or other periodic maintenance? Or other services that Feastrex owners will need a few years after purchase? I'm sure sensible people will want a solid relationship with the authorized dealer, similar to what Lowther customers rely on. I can't wait to hear what the new lower prices will be!
I need to clarify things as I think I owe my fellow distributors an apology. I certainly did not mean to single any one out or to imply that these things are occuring. Rather, I was trying, clumsily, to make the case that US enthusiasts should no longer chafe at the difference in price between here and elsewhere. I could write a long dissertation as to why I feel our higher pricing was actually the correct way to go, but it is difficult to fight upstream, when the rest of the world is going another way.
This from Chris Witmer who is unable to post at the moment:
To say that Feastrex drivers are a real pain in the neck to recone is
putting it mildly. For all intents and purposes, re-coning should be
considered something that can be done only by the manufacturer. Originally
Hal Teramoto learned how to cone drivers from Exact's Takashi Sano, and
although their techniques are different, in theory they could recone each
others' drivers. So right now there are two people living in the world who
can recone a Feastrex driver. Neither of them are what you would call
"spring chickens."
This is not a good thing. Can you imagine if in the late 18th century
someone had said, "Oh, I see that a seam in my Antonino Stradivari violin
has opened up and the sound is going to the dogs, after just 70 years! But
he's dead and nobody can repair it, so I guess I have no choice but to toss
it into the fireplace." Wouldn't that have been a crazy situation? Thank God
the secrets of violin making and repair did not die with Antonio
Stradivarius. Perhaps the comparison with Feastrex is overblown, but there
is no reason why a properly maintained Feastrex driver should not continue
to produce beautiful music for centuries. If all goes well, a pair of
Feastrex drivers will probably outlive their owner without requiring
maintenance. But accidents do happen, and eventually the leather surrounds
will need to be replaced. It would be a shame if the two men who are
currently capable of re-coning Feastrex drivers shuffled off this mortal
coil without passing on their art to anyone else.
In a few days Feastrex will be welcoming a young man who is interested in
becoming an apprentice to Hal Teramoto. Who knows how this will turn out? It
is impossible to say in advance. For some people, it is probably a career
choice made in heaven, for others a career choice made in hell, and for
others somewhere in between. The only way to find out whether someone has
the aptitude is to try it. Hal Teramoto says that if things do work out, and
assuming this young man has an aptitude comparable to Hal's own, it will
probably take two years to get to to the point where he can assemble a
Feastrex driver entirely on his own. Since there are not a lot of examples
from which one can determine an average, it might take more time or less.
That's assuming the arrangement works out. But regardless of what happens,
Hal Teramoto tells me that Feastrex is committed to ensuring continuity in
order to protect the long-term interests of customers who have spent large
amounts of money on these drivers. One way or another they are determined to
see that the art of building and repairing a Feastrex type fullrange driver
is not allowed to disappear. If this one apprentice works out, then perhaps
at some point in the future they can think of taking on another, and of
course each successful apprentice can in turn pass his skills on to others.
(I wonder what you call such a person -- as opposed to a "luthier," perhaps
a "transducier"?)
The great instrument models of centuries past were precisely measured and
continue to serve as templates for luthiers today. Nevertheless, each
luthier puts his own individual character into each instrument and no
luthier's work can be truly replicated by any other. In the same way, it
would be possible to measure the dimensions of Feastrex type fullrange
drivers and have them serve as standards based upon which at any given time
there could be several artisans producing their own variants around the
world. The basic key materials would probably remain the same; in several
centuries there will still be leather, copper wire, Japanese handmade
mulberry paper, urushi lacquer, and all the other materials used in the
drivers, along with other naturally-derived and sustainable materials that
are eventually discovered to work well with these drivers. Even if you gave
two artisans the exact same materials to work with and they attempted to do
the same work, the results would not be exactly the same. But they could be
close enough so that anyone who purchased a pair of these exotic drivers
could rest assured that his purchase would never be rendered obsolete due to
the untimely expiration of their builder, since he is not the only person on
the planet capable of repairing them in the event something happens to them.
So, what can happen that might require servicing?
* The leather surrounds wear out. (This is going to take a LONG time to
happen, and it might be your heir who has to worry about it.)
* Right now Feastrex is big on phase plugs, but it would be possible to have
drivers with metal dome dust caps over the voice coil former instead. They
do produce some OEM drivers like this. These are very fragile and kids of
all ages, from 5 to 55, can easily put their finger right through them.
Metal dust cap drivers could need repairs on account of damage to the dust
cap.
* Phase plug drivers can get magnetic particles stuck in the voice coil gap.
This is less of a problem for the field coil drivers as the strong magnetic
field can be stopped by turning off power to the field coil. A judicious jet
of air might blow the offending particle(s) out. But if something does get
stuck in the voice coil gap, it is conceivable that reconing might be needed
to fix it.
* Someone accidentally damages the whizzer cone, such as while attaching or
removing the phase plug.
* The main cone is quite strong but it is conceivable that a pointed object
could pierce it.
* The driver could be dropped so that it lands on the basket, bending or
cracking it.
* Upgrading or rebuilding into a different type of driver. This could be a
Feastrex project or a third party project. After all, Exact uses dual voice
coils and it is conceivable that someone could want to use a feedback coil,
etc.
* Damage during shipping
Re-calibration of the driver is not likely to be necessary. By the way, one
reason why Feastrex has not been interested in cantilever/thread/wire type
suspension systems is because they want the drivers to be as positionally
stable over time as possible, and because the drivers themselves are not
nearly as "user serviceable" as Lowthers and some others are.
-- Chris
To say that Feastrex drivers are a real pain in the neck to recone is
putting it mildly. For all intents and purposes, re-coning should be
considered something that can be done only by the manufacturer. Originally
Hal Teramoto learned how to cone drivers from Exact's Takashi Sano, and
although their techniques are different, in theory they could recone each
others' drivers. So right now there are two people living in the world who
can recone a Feastrex driver. Neither of them are what you would call
"spring chickens."
This is not a good thing. Can you imagine if in the late 18th century
someone had said, "Oh, I see that a seam in my Antonino Stradivari violin
has opened up and the sound is going to the dogs, after just 70 years! But
he's dead and nobody can repair it, so I guess I have no choice but to toss
it into the fireplace." Wouldn't that have been a crazy situation? Thank God
the secrets of violin making and repair did not die with Antonio
Stradivarius. Perhaps the comparison with Feastrex is overblown, but there
is no reason why a properly maintained Feastrex driver should not continue
to produce beautiful music for centuries. If all goes well, a pair of
Feastrex drivers will probably outlive their owner without requiring
maintenance. But accidents do happen, and eventually the leather surrounds
will need to be replaced. It would be a shame if the two men who are
currently capable of re-coning Feastrex drivers shuffled off this mortal
coil without passing on their art to anyone else.
In a few days Feastrex will be welcoming a young man who is interested in
becoming an apprentice to Hal Teramoto. Who knows how this will turn out? It
is impossible to say in advance. For some people, it is probably a career
choice made in heaven, for others a career choice made in hell, and for
others somewhere in between. The only way to find out whether someone has
the aptitude is to try it. Hal Teramoto says that if things do work out, and
assuming this young man has an aptitude comparable to Hal's own, it will
probably take two years to get to to the point where he can assemble a
Feastrex driver entirely on his own. Since there are not a lot of examples
from which one can determine an average, it might take more time or less.
That's assuming the arrangement works out. But regardless of what happens,
Hal Teramoto tells me that Feastrex is committed to ensuring continuity in
order to protect the long-term interests of customers who have spent large
amounts of money on these drivers. One way or another they are determined to
see that the art of building and repairing a Feastrex type fullrange driver
is not allowed to disappear. If this one apprentice works out, then perhaps
at some point in the future they can think of taking on another, and of
course each successful apprentice can in turn pass his skills on to others.
(I wonder what you call such a person -- as opposed to a "luthier," perhaps
a "transducier"?)
The great instrument models of centuries past were precisely measured and
continue to serve as templates for luthiers today. Nevertheless, each
luthier puts his own individual character into each instrument and no
luthier's work can be truly replicated by any other. In the same way, it
would be possible to measure the dimensions of Feastrex type fullrange
drivers and have them serve as standards based upon which at any given time
there could be several artisans producing their own variants around the
world. The basic key materials would probably remain the same; in several
centuries there will still be leather, copper wire, Japanese handmade
mulberry paper, urushi lacquer, and all the other materials used in the
drivers, along with other naturally-derived and sustainable materials that
are eventually discovered to work well with these drivers. Even if you gave
two artisans the exact same materials to work with and they attempted to do
the same work, the results would not be exactly the same. But they could be
close enough so that anyone who purchased a pair of these exotic drivers
could rest assured that his purchase would never be rendered obsolete due to
the untimely expiration of their builder, since he is not the only person on
the planet capable of repairing them in the event something happens to them.
So, what can happen that might require servicing?
* The leather surrounds wear out. (This is going to take a LONG time to
happen, and it might be your heir who has to worry about it.)
* Right now Feastrex is big on phase plugs, but it would be possible to have
drivers with metal dome dust caps over the voice coil former instead. They
do produce some OEM drivers like this. These are very fragile and kids of
all ages, from 5 to 55, can easily put their finger right through them.
Metal dust cap drivers could need repairs on account of damage to the dust
cap.
* Phase plug drivers can get magnetic particles stuck in the voice coil gap.
This is less of a problem for the field coil drivers as the strong magnetic
field can be stopped by turning off power to the field coil. A judicious jet
of air might blow the offending particle(s) out. But if something does get
stuck in the voice coil gap, it is conceivable that reconing might be needed
to fix it.
* Someone accidentally damages the whizzer cone, such as while attaching or
removing the phase plug.
* The main cone is quite strong but it is conceivable that a pointed object
could pierce it.
* The driver could be dropped so that it lands on the basket, bending or
cracking it.
* Upgrading or rebuilding into a different type of driver. This could be a
Feastrex project or a third party project. After all, Exact uses dual voice
coils and it is conceivable that someone could want to use a feedback coil,
etc.
* Damage during shipping
Re-calibration of the driver is not likely to be necessary. By the way, one
reason why Feastrex has not been interested in cantilever/thread/wire type
suspension systems is because they want the drivers to be as positionally
stable over time as possible, and because the drivers themselves are not
nearly as "user serviceable" as Lowthers and some others are.
-- Chris
I might add that in general, the price of Feastrex drivers can be expected to continue to rise in the future, although there might be mitigating factors against that (e.g., if a certain scale of manufacturing can be achieved, it might bring manufacturing costs down somewhat). In fact, it is my understanding that Feastrex has just raised its prices for several models, particularly those using Permendur. The materials most likely to go up in price are Permendur, pure iron, and bronze. Other metals are likely to be similarly affected, but to a lesser degree. The fact that the Lotus Group announced a reduction of prices even while experiencing an increase in their own purchase prices is something that deserves high praise, in my opinion. Given the rationale for the original pricing structure, I imagine that it must not have been an easy decision and I can sense a genuine desire on Joe's part to do what he can to get these drivers into the hands of as many potential purchasers as possible, even if it means some additional effort and sacrifice on his part. Thanks for sharing the love, Joe!
My advice to people who have their heart set on purchasing Feastrex drivers -- especially those using Permendur and/or pure iron -- do it sooner rather than later! Prices are not going to go down in the future. In fact, anyone who purchased such drivers early on has probably seen his drivers appreciate in value simply due to the constant upward trend of prices for certain metals.
And if I may add a brief political comment, what we are witnessing is not price inflation so much as the debasement of the currency. The powers that be are solidly committed to inflating their way out of their (our) problems. . . if that can be called a "solution." It may sound somewhat cynical, but it might be a good idea to spend your dollars now before they disappear in your pocket . . .
-- Chris
My advice to people who have their heart set on purchasing Feastrex drivers -- especially those using Permendur and/or pure iron -- do it sooner rather than later! Prices are not going to go down in the future. In fact, anyone who purchased such drivers early on has probably seen his drivers appreciate in value simply due to the constant upward trend of prices for certain metals.
And if I may add a brief political comment, what we are witnessing is not price inflation so much as the debasement of the currency. The powers that be are solidly committed to inflating their way out of their (our) problems. . . if that can be called a "solution." It may sound somewhat cynical, but it might be a good idea to spend your dollars now before they disappear in your pocket . . .
-- Chris
A Visit to Feastrex
If all has gone as planned...My son Porter is on his way the the Feastrex factory with Chris W....
His job is to listen to Hal's work and report back. I can't wait to hear what he has to say about that $60,000 usd driver...
I will post his findings.
Yea, The kids got ears.
Actually he is no longer a kid but what the hell.
Suffering in Santa Fe with just a pair of 5Dnf's.
Phil
If all has gone as planned...My son Porter is on his way the the Feastrex factory with Chris W....
His job is to listen to Hal's work and report back. I can't wait to hear what he has to say about that $60,000 usd driver...
I will post his findings.
Yea, The kids got ears.
Actually he is no longer a kid but what the hell.
Suffering in Santa Fe with just a pair of 5Dnf's.
Phil
The bad news, the worse news, and the good news
The bad news is that I can't go to visit Feastrex's listening room due to work obligations.
The worse news is that Phil's son will not be going either
The good news is that another American friend of Mike Luckow who lives in Tokyo, and who is probably (objectively speaking) a better judge of audio than I am, is going to be going and has graciously agreed to give a report.
This fellow visited Feastrex with Mike and me a little less than a year ago, and furthermore he briefly had the use (for a month or two, I believe) of a pair of D5 "monster magnet" drivers in Feastrex enclosures, along with Mr. Teramoto's personal R120 SE amplifier.
If my understanding is correct, right now this gentleman does not have much of a stereo system, having moved from overseas not too long ago, but in the past he had Spendor LS3/5 type speakers and very nice tube electronics as well as good vinyl and digital sources, so I think he should be able to give us a good report.
I'm looking forward to it!
-- Chris
The bad news is that I can't go to visit Feastrex's listening room due to work obligations.
The worse news is that Phil's son will not be going either
The good news is that another American friend of Mike Luckow who lives in Tokyo, and who is probably (objectively speaking) a better judge of audio than I am, is going to be going and has graciously agreed to give a report.
This fellow visited Feastrex with Mike and me a little less than a year ago, and furthermore he briefly had the use (for a month or two, I believe) of a pair of D5 "monster magnet" drivers in Feastrex enclosures, along with Mr. Teramoto's personal R120 SE amplifier.
If my understanding is correct, right now this gentleman does not have much of a stereo system, having moved from overseas not too long ago, but in the past he had Spendor LS3/5 type speakers and very nice tube electronics as well as good vinyl and digital sources, so I think he should be able to give us a good report.
I'm looking forward to it!
-- Chris
Thank you for the kind words, Chris. We do indeed want more people joining the Feastrex family. We realize that for many it will be a stretch to purchase a pair of drivers, whether that stretch is toward the d5nf or the D9e. The important thing to keep in mind is, as Mr. Teramoto said of the D9e Type II when we first heard them here, "these are cheap". What he means is that the ratio of performance achieved for dollars spent is inordinantly high. Once a larger segment of the general audio populace realizes this there could very well be a stampede to buy Feastrex products.
New price list attached
New price list attached
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