Secips said:
Yes. And no. More to the first: since the surrounds don't deteriorate like urethane and rubber edges do, the parameters are stable. The drivers do have a very long run-in phase that they go through -- the sound continues to gradually improve over one year, at least -- but I don't think the changes that are heard have much to do with the T/S parameters.
At one point Lotus Group was considering participating in the upcoming show in Montreal but I think they have nixed that idea, figuring that RMAF and CES (T.H.E. Show) were enough for the time being . . . I'm sure there would be interest among audiophiles in the NYC area for a demo, but it would be quite a trek from the West Coast. There are users in the Southeast -- VA/NC/FL -- if you ever have an opportunity to travel south.
-- Chris
Secips said:
Do keep in mind that T/S parameters will likely change more due to weather and to where you have the volume set than they will over an extended period of aging (assumming a reasonable breakin period is ignored). AlNiCo itself will age other time and is likely the biggest aging concern.
dave
People using Feastrex drivers (all 16 ohm) with 8-ohm valve amplifiers may benefit from impedance matching autoformers like the ones shown below.
The above transformers are now being auctioned on a Japanese Yahoo! auction for a starting price of 5,000 yen for the pair, which is pretty good (although postage must be figured in too). I have no connection with the auction, but here is a link if anyone is interested:
Tango FT-200-16�@Hi-Fi AutoTrans
http://page9.auctions.yahoo.co.jp/jp/auction/k49323300
A more expensive solution ($450) is this:
http://www.zeroimpedance.com/
-- 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.
An externally hosted image should be here but it was not working when we last tested it.
The above transformers are now being auctioned on a Japanese Yahoo! auction for a starting price of 5,000 yen for the pair, which is pretty good (although postage must be figured in too). I have no connection with the auction, but here is a link if anyone is interested:
Tango FT-200-16�@Hi-Fi AutoTrans
http://page9.auctions.yahoo.co.jp/jp/auction/k49323300
A more expensive solution ($450) is this:
http://www.zeroimpedance.com/
-- Chris
While you can certainly invest in matching transformers, I would make that option number two. My first choice would be to invest in new output transformers with a 16-ohm secondary winding. Chances are you'll be able to get better outputs than you have now for a low delta.... and there are lots of choices, just my $0.02 (which is actually worth less now).
Regards, KM
Regards, KM
Planet10,
I just went through the thread and just echoing the concerns of the use of leather as a surround. Then again, it doesn't really matter as long as it sounds good. From reports the sound improves like fine wine, so the idea of making a new enclosure is moot. Don't fix it if it ain't broke.
cdwitmer and kmaier,
Thanks, for the headsup that these only come in 16 ohms. I have a 6C33C SE amp, requires a special tranny. I'm sure I could get one or make a new amp altogether.
Anyway, just trying to get informed and digest all this info. I have little experience with FR and I am very thankful to those who help me. I am but your student. I am also looking at PHY, Hemptone, AudioNirvana, Lowthers and the list getting longer. Presently, I'm quite impressed with the speakers produced with PHY. From my perspective, the creativity infused with these designs could only be inspired by the speaker. Personally, I view speakers to be a musical instrument and would follow that path. Making a piano is on my to-do-list, someday. Anyway, going back to the subject at hand I was equally impressed by Feastrex's company motto. I firmly believe that purity of intent breeds the clarity of thought.
I just went through the thread and just echoing the concerns of the use of leather as a surround. Then again, it doesn't really matter as long as it sounds good. From reports the sound improves like fine wine, so the idea of making a new enclosure is moot. Don't fix it if it ain't broke.
cdwitmer and kmaier,
Thanks, for the headsup that these only come in 16 ohms. I have a 6C33C SE amp, requires a special tranny. I'm sure I could get one or make a new amp altogether.
Anyway, just trying to get informed and digest all this info. I have little experience with FR and I am very thankful to those who help me. I am but your student. I am also looking at PHY, Hemptone, AudioNirvana, Lowthers and the list getting longer. Presently, I'm quite impressed with the speakers produced with PHY. From my perspective, the creativity infused with these designs could only be inspired by the speaker. Personally, I view speakers to be a musical instrument and would follow that path. Making a piano is on my to-do-list, someday. Anyway, going back to the subject at hand I was equally impressed by Feastrex's company motto. I firmly believe that purity of intent breeds the clarity of thought.
Secips said:
You might start with a clavichord . . . it's probably a lot easier. Funny you should mention making a piano; I recently repaired a cracked cast iron plate in one of our pianos. That was quite a project and one that I hope I never have to repeat. After four tunings the repair seems to have been a huge success -- it sounds great -- and it would not have been possible without a LOT of help from Feastrex's Mr. Teramoto and one of Feastrex's parts suppliers. The repair was made without disassembling the piano (although I did loosen all the strings and removed some of them completely to get access to the plate). The repair was made entirely without using any heat. I reinforced the most vulnerable part of the plate with a "tapering, round-cornered triangle" made of steel measuring 5cm thick and with a periphery measuring about 45 cm (sum of the three sides). Since the cast iron plate was not exactly what you'd call a precision casting, Mr. Teramoto's parts supplier machined the chunk of steel so it was a close fit but a tad oversized, and then I used a disk grinder to tweak it into an almost perfect fit. The reinforcement was finally held in place with epoxy and my neighbor who runs an auto body repair shop matched the color of the paint pretty well so I could make the repair invisible. That hardly explains all of what had to be done -- the piano stood broken for a whole year while I researched and prepared for the actual repair, and also saved up money for the expense involved. In the end, though, the repair was effected for about half of the cost of getting a conventional repair, which would have involved a complete removal of the plate from the piano, welding, annealing, and reassembling. Only time will tell but I think that if anything the approach that I ended up taking gave better results than the conventional approach. My piano technician was astounded by my balls and determination -- nobody else in Japan has ever repaired a piano this way, I'm sure -- and by the fact that ordinary people with zero experience in such a thing would attempt it, and pull it off. (There's a good 30 tons of strain on the plate from the strings.) But the folks around Feastrex are no ordinary "ordinary people" -- those guys are crazy geniuses, and a piano is just a big fullrange speaker anyway. We had some interesting and rather heated discussions about minutiae of the repair. They know from experience that even tiny changes, such as the type of metal used in a thin washer or screw, can affect the sound significantly, and they wanted to do as little as possible to minimize any changes in the sound. I wanted a belt-and-suspenders repair and was willing to accept a change in the sound to get an extra measure of strength. We finally decided on a compromise that satisfied everyone. Without the help of Mr. Teramoto and his supplier, I could not have afforded to repair the piano and it would have ended up being scrapped -- not something I wanted to do since it is a rather rare piano with a lot of sentimental value.
cdwitmer,
Bravo! Necessity is the mother of all invention. I thoroughly enjoyed that. You remind me of my friend who makes pianos for living. He discusses the design of his soundboard with the same enthusiasm and pride (accordingly so) as you do with your repair. I promised him that one day, I'll apprentice with him. I didn't realize that you are much more involved with Feastrex. It is good know that people in Feastrex truly have a passion for their selected profession, true artisans. I am glad you were able to save your priceless piano. You definitely have huge "ones"
.
Bravo! Necessity is the mother of all invention. I thoroughly enjoyed that. You remind me of my friend who makes pianos for living. He discusses the design of his soundboard with the same enthusiasm and pride (accordingly so) as you do with your repair. I promised him that one day, I'll apprentice with him. I didn't realize that you are much more involved with Feastrex. It is good know that people in Feastrex truly have a passion for their selected profession, true artisans. I am glad you were able to save your priceless piano. You definitely have huge "ones"
.
Secips said:I didn't realize that you are much more involved with Feastrex. It is good know that people in Feastrex truly have a passion for their selected profession, true artisans. I am glad you were able to save your priceless piano. You definitely have huge "ones"
Actually, it's not that I'm involved with Feastrex so much as that Mr. Teramoto and his parts supplier genuinely felt sorry for my family. After one year, my wife had reached the limits of her patience with the broken piano. We've got seven kids who all play the piano and the only functioning piano was in the main living area. The kids were playing on the piano from morning until night, day in and day out (they're homeschooled so they are literally with their mother 24x7) and she was getting quite stressed out. She wanted another functioning keyboard instrument in a more remote part of the house, not a broken piano occupying precious space. The one with the huge keesters was my wife, who got on my back to get the piano finally fixed, and Mr. Teramoto and his parts supplier, who had the experience to critique my ideas and come up with implementable solutions.
Some of you might find this thread interesting as well --
http://www.diyaudio.com/forums/showthread.php?s=&postid=1429939
-- Chris
http://www.diyaudio.com/forums/showthread.php?s=&postid=1429939
-- Chris
Another post from the Japanese blogger:
http://shinshu.fm/MHz/44.04/archives/0000227391.html
"I like fullrange speakers"
Last year the much-awaited Fostex FE208ES-R went on sale, but unfortunately there were only 500 units and I was not able to get my hands on them. Now the follow-up model, the FE138ES-R is on sale. I expect that most speaker enclosure DIY fans have obtained both.
The 20cm FE208ES-R has an alnico magnet, pure iron pole piece, silver voice coil and carbon/biocellulose hybrid cone. M0=12g, Q0=0.16, magnet weight=3100g, SPL=99dB, total weight��6.3Kg
The 13cm FE138ES-R has a similar concept to the FE208ES-R. M0=5g, Q0=0.27, magnet weight=1490g, SPL=91.5dB, total weight=2.86Kg
At Koizumi Musen I listened to a "Turkey" enclosure with the FE138ES-R in it -- a very tight sound with depth to it, wonderful. I would have liked Tetsuo Nagaoka to be around to design an enclosure for this. I bet Nagaoka fans around Japan are busily designing Swan or Turkey enclosures for these drivers.
And then appears my true beau . . .
The Feastrex D5nf (12cm) is the one. With a highly efficient spherical magnetic circuit and cone assembly that is light in weight (despite the incredible thickness of the handmade Japanese paper in the cone), the whizzer cone is made of "ganpi" paper and it has leather surrounds. I expect these units will still be going strong when they are passed on to my son.
SPL=95dB, total weight=15Kg
I thought I was going to pass out or empty my bladder from the excitement of listening to the sound of these units. There is something very unique about the highly articulate sound of their lightweight diaphragms. With such high SPL (for their size) they are no poofters, and they handle high power very well.
Unemployed "yours truly" doesn't have the money for such a purchase . . . I need to shut my eyes to other distractions and find a job . . .
http://shinshu.fm/MHz/44.04/archives/0000227391.html
"I like fullrange speakers"
Last year the much-awaited Fostex FE208ES-R went on sale, but unfortunately there were only 500 units and I was not able to get my hands on them. Now the follow-up model, the FE138ES-R is on sale. I expect that most speaker enclosure DIY fans have obtained both.
The 20cm FE208ES-R has an alnico magnet, pure iron pole piece, silver voice coil and carbon/biocellulose hybrid cone. M0=12g, Q0=0.16, magnet weight=3100g, SPL=99dB, total weight��6.3Kg
The 13cm FE138ES-R has a similar concept to the FE208ES-R. M0=5g, Q0=0.27, magnet weight=1490g, SPL=91.5dB, total weight=2.86Kg
At Koizumi Musen I listened to a "Turkey" enclosure with the FE138ES-R in it -- a very tight sound with depth to it, wonderful. I would have liked Tetsuo Nagaoka to be around to design an enclosure for this. I bet Nagaoka fans around Japan are busily designing Swan or Turkey enclosures for these drivers.
And then appears my true beau . . .
The Feastrex D5nf (12cm) is the one. With a highly efficient spherical magnetic circuit and cone assembly that is light in weight (despite the incredible thickness of the handmade Japanese paper in the cone), the whizzer cone is made of "ganpi" paper and it has leather surrounds. I expect these units will still be going strong when they are passed on to my son.
SPL=95dB, total weight=15Kg
I thought I was going to pass out or empty my bladder from the excitement of listening to the sound of these units. There is something very unique about the highly articulate sound of their lightweight diaphragms. With such high SPL (for their size) they are no poofters, and they handle high power very well.
Unemployed "yours truly" doesn't have the money for such a purchase . . . I need to shut my eyes to other distractions and find a job . . .
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.