I'm happy to forward, or they could be picked up from Coburg in Melbourne, or Carlton during business hours.
The combined shipping sounds good, very good. But before I buy, I'm also interested in the PT from the Sony 500a (if it has dual 120v primaries) and the tubes from one of the 500a's. Let me know.
That sounds excellent, I'm always up for combining shipping. Let me figure out what I'm getting first and then we should be sweet.
I've been selling The tube-rectified power supplies that were originally spec'd with the TamRadio OPTs for $40 ea. Here's the schematic. http://www.diyaudio.com/forums/showpost.php?p=1403379&postcount=240 They have selectable voltage input with six settings between 100v and 240v.
Again, if it's part of the larger order, I can take 10% off.
Again, if it's part of the larger order, I can take 10% off.
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Fostex RM780 Dissection
Please excuse the horrendous quality of the pics below. I couldn't find my camera, so the cell-cam had to do.
Here is a post-mortem dissection of an open-circuit Fostex RM780. As I mentioned above, I've always liked how these drivers sound, and I think I found out why when I uncovered the hidden bits of quality engineering. These were intended to be high-accuracy monitors, and the Fostex engineers clearly were given their head on this project, because it looks like they didn't cut any corners that matter.
First pic, the driver front and back. The quasi-point-source nature of coaxials is a great starting point, sidestepping many lobing/power-response issues inherent in even the finest non-coaxial multi-way systems.
Also notice the crescent structure on the cone visible through the basket window. It's one of three pieces of high-loss polymer shaped to absorb and diffuse cone breakup.
Please excuse the horrendous quality of the pics below. I couldn't find my camera, so the cell-cam had to do.
Here is a post-mortem dissection of an open-circuit Fostex RM780. As I mentioned above, I've always liked how these drivers sound, and I think I found out why when I uncovered the hidden bits of quality engineering. These were intended to be high-accuracy monitors, and the Fostex engineers clearly were given their head on this project, because it looks like they didn't cut any corners that matter.
First pic, the driver front and back. The quasi-point-source nature of coaxials is a great starting point, sidestepping many lobing/power-response issues inherent in even the finest non-coaxial multi-way systems.
Also notice the crescent structure on the cone visible through the basket window. It's one of three pieces of high-loss polymer shaped to absorb and diffuse cone breakup.
Attachments
Moving deeper into the guts.
Here we have a very nice curvelinear-profile wide-band paper cone with damped fabric surround. The nifty little breakup diffusers are easier to see here. Notice also the dual mirror-image spiders (they're identical size, I just cut one smaller when I sliced through it). They help eliminate VC rocking, and their mirror-image orientation means most spider modes are canceled by anti-phase modes in the other spider.
The motor features quite a large magnet. Its crowning jewel is a generous copper shorting sleeve that covers the entire gap and folds over onto the top of the pole piece. This is pretty much ideal coverage for a shorting ring and does a number of very nice things for motor linearity, both in the small and large-signal realms.
Here we have a very nice curvelinear-profile wide-band paper cone with damped fabric surround. The nifty little breakup diffusers are easier to see here. Notice also the dual mirror-image spiders (they're identical size, I just cut one smaller when I sliced through it). They help eliminate VC rocking, and their mirror-image orientation means most spider modes are canceled by anti-phase modes in the other spider.
The motor features quite a large magnet. Its crowning jewel is a generous copper shorting sleeve that covers the entire gap and folds over onto the top of the pole piece. This is pretty much ideal coverage for a shorting ring and does a number of very nice things for motor linearity, both in the small and large-signal realms.
Attachments
And finally, a closer look at the tweeter.
This is essentially a horn-loaded planar thin-film polymer diaphragm printed with a spiral voice coil and suspended in a radial magnetic field produced by an array of three ring-shaped rare-earth magnets (that fly apart energetically when released, and it's a real trick to put back together.) Again, it looks like a unique no-corners-cut engineering effort by Fostex.
In all, I've never seen anything quite like these coaxial drivers that so outclass the drab boxes they come in. I'd love to chat with the lead engineer and hear the inside scoop. Clearly a labor of love.
This is essentially a horn-loaded planar thin-film polymer diaphragm printed with a spiral voice coil and suspended in a radial magnetic field produced by an array of three ring-shaped rare-earth magnets (that fly apart energetically when released, and it's a real trick to put back together.) Again, it looks like a unique no-corners-cut engineering effort by Fostex.
In all, I've never seen anything quite like these coaxial drivers that so outclass the drab boxes they come in. I'd love to chat with the lead engineer and hear the inside scoop. Clearly a labor of love.
Attachments
Hi Pallas,
This is an 8" coaxial driver from a Fostex RM780 studio monitor speaker. (I am selling two pairs of these.) Fostex also made a 6" version.
Fostex came out with the three-model RM line in the mid-eighties. The drivers are gems, but Fostex hid them in ugly, junky, vinyl-laminated chip-board boxes--maybe in an effort to save the extra money that must have gone into driver development and production. I imagine the poor visual presentation of the boxes torpedoed the perceived value of the line, because Fostex didn't produce them for very long, as far as I can tell.
After hearing how well these RM coaxials perform, I became sort of a collector, buying up whatever I found (which wasn't very much). I've owned all three RM models. Now I'm just trying to shrink my collection a bit in the interest of space.
I think I have a technical brochure about the RM line somewhere around here. I'll post scans when I find it.
Bill
This is an 8" coaxial driver from a Fostex RM780 studio monitor speaker. (I am selling two pairs of these.) Fostex also made a 6" version.
Fostex came out with the three-model RM line in the mid-eighties. The drivers are gems, but Fostex hid them in ugly, junky, vinyl-laminated chip-board boxes--maybe in an effort to save the extra money that must have gone into driver development and production. I imagine the poor visual presentation of the boxes torpedoed the perceived value of the line, because Fostex didn't produce them for very long, as far as I can tell.
After hearing how well these RM coaxials perform, I became sort of a collector, buying up whatever I found (which wasn't very much). I've owned all three RM models. Now I'm just trying to shrink my collection a bit in the interest of space.
I think I have a technical brochure about the RM line somewhere around here. I'll post scans when I find it.
Bill
Notice the RM780's impressive harmonic distortion numbers (page 3). Less than 0.5% 3rd harmonic distortion above 100Hz. And that's at TEN watts/100dB! Very good for an 8" driver.
I wish all driver manufacturers would publish measurements at the 100dB level like this. Standard 1W ratings hide way too much.
I wish all driver manufacturers would publish measurements at the 100dB level like this. Standard 1W ratings hide way too much.
Just realised the condition of my bank account, won't be able to take the OPTs.
What have you got in the way of tubes you'd be willing to part with?
Hello,
the Radian 475PB (one pair ) are still available?
They are in good conditions?
Have a nice day.
Guglielmo
the Radian 475PB (one pair ) are still available?
They are in good conditions?
Have a nice day.
Guglielmo
Here's the most recent list update.
Just ask if you see something interesting that doesn't have a price quoted. I am sometimes open to cutting deals for multiple-item purchases.
Loudspeakers / systems:
EV MS-802 monitor pair (needs woofer refoam)
EV Interface A pair
Foster/Fostex FE103a pair in cabs w/original Admiral TT/tuner/amp -- $175
Fostex RM780 coaxial monitors $120/pr.
KEF C35 coaxial speaker pair -- $100
Artcoustic Diablo mini monitor pair -- $160
Fullrange / wideband drivers:
Babb Lorelei L6 driver pair (one rubs) $170
Coral white-cone pair -- 8-ohm FE103a holey-basket variant -- $75
Lang & Taylor 8" fr driver pair (one rubs)
Pioneer PIM-8L single
Pioneer 6" Mechanical 2-way single (like PIM8L)
Stephens FR120 single
Strange oblong alnico driver pair
University phenolic cone driver pair (ancient, like Western Electric)
Wharfedale Super 8/RS/DD pair (extremely nice!) -- $120
Wharfedale bronze pair (like Super 8) -- $40
Woofers / midranges / coaxial drivers:
AuraSound NRT 1808 driver single -- $550
Coral 8CX-50 pair -- $80
EV EVM-15B drivers $200/pr.
EV Sentry 100A repl. Woofer
Fostex RM860 drivers (bass & coax pairs) and XOs $175
Huge old Racon Alnico 15" woofer
JBL 2152H coax speaker pair -- $250
JBL 2152H coax speaker pair (paint spatter on cones) -- $175
JBL 2104H 4" driver pair for horn-loading used in Vertec arrays -- $75
JBL E145 8 single -- $170
Knight KN810 15" driver single (Jensen OEM w/ coaxial RP302 tweeter) -- $200
Radian 2215 pair 15" woofers (with deluxe cast baskets) -- $220
Radian 210/2B pair 10" woofers, brand new -- $110
Tannoy CMS65 ICT pair -- $80
Tannoy CMS6 coaxial pair (w/crossovers) -- $175
Compression drivers:
Emilar EA-175 driver pair: $50
EV DH1A compression driver pair -- $200
EV ST350a supertweeters (6) (need diaphrams)
JBL 2360 throat single
JBL 2356 throat pair
Radian 465PB driver pair (need diaphragms)
Selenium ST320 slot tweeter pair + extra diaphragm -- $100
Amplifiers:
Biamp MCA 8050 8-channel amp -- $350
Blaupunkt PA275 amp (tripath) -- $65
JBL MPC300 amplifier brand new -- tested, never used, $225
Koss KS5192 receiver/player (for parts--nice TI pure-path amp / SMPS) -- $20
Crest Audio amplifier
Sources:
Grado Green Phono cartridge -- used once, $70
MCS & Technics Turntables
Signal processors / crossovers / switches
Alps motorized 6-gang pots -- $30
Behringer Ultrabass Pro EX 1200 sub-harmonic synthesizer / XO -- $100
Biamp MSP-11 Multi-function System Processor / XO / EQ
Ceramic rotary switch pair
Radian XO PCBs (9) -- $4/ea.
6 105-pin rotary printer switches
Parts, etc.:
Avel toroid power transformer--large-- (2x 120v primaries, 2x 50v secondaries) $45
Dual-ganged HEAVY-DUTY variacs
Thomas vacuum pump
Sharp Notevision3 projector for parts
Vintage Tamura 5k SE Output Transformers for EL84/6BQ5 -- $75/pr.
Tube-rectified power supply for stereo EL84/6BQ5 -- $40
Just ask if you see something interesting that doesn't have a price quoted. I am sometimes open to cutting deals for multiple-item purchases.
Loudspeakers / systems:
EV MS-802 monitor pair (needs woofer refoam)
EV Interface A pair
Foster/Fostex FE103a pair in cabs w/original Admiral TT/tuner/amp -- $175
Fostex RM780 coaxial monitors $120/pr.
KEF C35 coaxial speaker pair -- $100
Artcoustic Diablo mini monitor pair -- $160
Fullrange / wideband drivers:
Babb Lorelei L6 driver pair (one rubs) $170
Coral white-cone pair -- 8-ohm FE103a holey-basket variant -- $75
Lang & Taylor 8" fr driver pair (one rubs)
Pioneer PIM-8L single
Pioneer 6" Mechanical 2-way single (like PIM8L)
Stephens FR120 single
Strange oblong alnico driver pair
University phenolic cone driver pair (ancient, like Western Electric)
Wharfedale Super 8/RS/DD pair (extremely nice!) -- $120
Wharfedale bronze pair (like Super 8) -- $40
Woofers / midranges / coaxial drivers:
AuraSound NRT 1808 driver single -- $550
Coral 8CX-50 pair -- $80
EV EVM-15B drivers $200/pr.
EV Sentry 100A repl. Woofer
Fostex RM860 drivers (bass & coax pairs) and XOs $175
Huge old Racon Alnico 15" woofer
JBL 2152H coax speaker pair -- $250
JBL 2152H coax speaker pair (paint spatter on cones) -- $175
JBL 2104H 4" driver pair for horn-loading used in Vertec arrays -- $75
JBL E145 8 single -- $170
Knight KN810 15" driver single (Jensen OEM w/ coaxial RP302 tweeter) -- $200
Radian 2215 pair 15" woofers (with deluxe cast baskets) -- $220
Radian 210/2B pair 10" woofers, brand new -- $110
Tannoy CMS65 ICT pair -- $80
Tannoy CMS6 coaxial pair (w/crossovers) -- $175
Compression drivers:
Emilar EA-175 driver pair: $50
EV DH1A compression driver pair -- $200
EV ST350a supertweeters (6) (need diaphrams)
JBL 2360 throat single
JBL 2356 throat pair
Radian 465PB driver pair (need diaphragms)
Selenium ST320 slot tweeter pair + extra diaphragm -- $100
Amplifiers:
Biamp MCA 8050 8-channel amp -- $350
Blaupunkt PA275 amp (tripath) -- $65
JBL MPC300 amplifier brand new -- tested, never used, $225
Koss KS5192 receiver/player (for parts--nice TI pure-path amp / SMPS) -- $20
Crest Audio amplifier
Sources:
Grado Green Phono cartridge -- used once, $70
MCS & Technics Turntables
Signal processors / crossovers / switches
Alps motorized 6-gang pots -- $30
Behringer Ultrabass Pro EX 1200 sub-harmonic synthesizer / XO -- $100
Biamp MSP-11 Multi-function System Processor / XO / EQ
Ceramic rotary switch pair
Radian XO PCBs (9) -- $4/ea.
6 105-pin rotary printer switches
Parts, etc.:
Avel toroid power transformer--large-- (2x 120v primaries, 2x 50v secondaries) $45
Dual-ganged HEAVY-DUTY variacs
Thomas vacuum pump
Sharp Notevision3 projector for parts
Vintage Tamura 5k SE Output Transformers for EL84/6BQ5 -- $75/pr.
Tube-rectified power supply for stereo EL84/6BQ5 -- $40
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