A question, before all hell breaks loose with this project. Do the output stage assemblies, and input boards fit the universal holes on the deluxe 4u chassis from the DIY store? Or do they only fit (without drilling/tapping) the special silver cases from the first two runs?
It would have been great to get a numbered case, but absent that, I might consider the 4u, or even the new mono chassis, and have more room to play with for input boards, and PSU filters. Although there is no indication, yet, of the availability of the monos, or if the will have the universal holes.
I did fair to good making M4 threaded holes for SissySIT. Without a drill press, doing all those M3 holes is a bit daunting.
It would have been great to get a numbered case, but absent that, I might consider the 4u, or even the new mono chassis, and have more room to play with for input boards, and PSU filters. Although there is no indication, yet, of the availability of the monos, or if the will have the universal holes.
I did fair to good making M4 threaded holes for SissySIT. Without a drill press, doing all those M3 holes is a bit daunting.
I bought a cheapo (approx $125) tabletop drill press from Amazon, and successfully used it to drill the heatsinks for an M2x. 7x M3 mounting holes for the PCB (drill and tap), plus 2x M3 mounting holes for the power transistor attachment bolts (drill and tap). A total of 9 holes per channel, times 2 channels for a stereo amp.
It was surprisingly straightforward, once I discovered it was best to draw a template on thick heavy paper, and tape that paper to the heatsink. (Rather than draw the template on the heatsink itself, or on masking tape attached to the heatsink). Then centerpunch, then drill. Then tap manually with lots of cutting fluid, and work very slowly. Break a tap and you are oh so screwwed.
I practiced drilling and tapping on a scrap piece of 10mm aluminum from a discarded project. Just to get a feel for the right pressure on the feed handle that lowers the chuck & drill bit. And to get a feel for the number of twists I could apply to the tap, before it begins to feel like it's binding. Then reverse out, wipe off the swarf, add more cutting fluid, and tap some more.
It was surprisingly straightforward, once I discovered it was best to draw a template on thick heavy paper, and tape that paper to the heatsink. (Rather than draw the template on the heatsink itself, or on masking tape attached to the heatsink). Then centerpunch, then drill. Then tap manually with lots of cutting fluid, and work very slowly. Break a tap and you are oh so screwwed.
I practiced drilling and tapping on a scrap piece of 10mm aluminum from a discarded project. Just to get a feel for the right pressure on the feed handle that lowers the chuck & drill bit. And to get a feel for the number of twists I could apply to the tap, before it begins to feel like it's binding. Then reverse out, wipe off the swarf, add more cutting fluid, and tap some more.
M2x is UMS pattern.
VFET Pchannel TO-3 output stage built by Nelson Pass and sold by lottery, is UMS pattern
VFET Nchannel TO-3 output stage built by Nelson Pass and sold by lottery, is UMS pattern
Front end card with Toshiba JFETs, designed by Nelson Pass and sold by lottery, is UMS pattern
Scourge, Bulwark, Marauder, Dreadnought, Relentless front ends cards are UMS pattern
All Ship Of Theseus front end and output stage cards are UMS pattern
Member Bones13 doesn't know (and neither do I), whether the add-VFETs-you-bought-yourself-onto-this-card-that-just-arrived-at-the-fulfillment-people , is or is not UMS pattern
VFET Pchannel TO-3 output stage built by Nelson Pass and sold by lottery, is UMS pattern
VFET Nchannel TO-3 output stage built by Nelson Pass and sold by lottery, is UMS pattern
Front end card with Toshiba JFETs, designed by Nelson Pass and sold by lottery, is UMS pattern
Scourge, Bulwark, Marauder, Dreadnought, Relentless front ends cards are UMS pattern
All Ship Of Theseus front end and output stage cards are UMS pattern
Member Bones13 doesn't know (and neither do I), whether the add-VFETs-you-bought-yourself-onto-this-card-that-just-arrived-at-the-fulfillment-people , is or is not UMS pattern
Hi,
sorry for my dumb question
I like my two bridged ACA monos, now I'm building two Aleph 60 monos, but in the background there is always a tiny evil devil who tells me "you should build a VFET-Amp!".
Well, everybody seems to have VFETs, perhaps even my stepaunt third degree
... but not me. The shop writes one shouldn't even try to buy from the bay because all "available" devices are fakes...
So... Do you have any hints or recommendations where to get VFETs enough for two monos? Or should I simply forget it, after killing my devil with some japanese Suntory whisky?
sorry for my dumb question
I like my two bridged ACA monos, now I'm building two Aleph 60 monos, but in the background there is always a tiny evil devil who tells me "you should build a VFET-Amp!".
Well, everybody seems to have VFETs, perhaps even my stepaunt third degree
... but not me. The shop writes one shouldn't even try to buy from the bay because all "available" devices are fakes...So... Do you have any hints or recommendations where to get VFETs enough for two monos? Or should I simply forget it, after killing my devil with some japanese Suntory whisky?
diyAudio member pras1170 is a reliable seller: https://www.diyaudio.com/community/...-from-japan-tokin.327309/page-17#post-6937987
Also ebay seller watanabetomoaki: https://www.ebay.ca/usr/watanabetomoaki/
Also ebay seller watanabetomoaki: https://www.ebay.ca/usr/watanabetomoaki/
@Plott, Ben has already given you links to known good sellers of the Tokin devices. And there are already some nice projects on this forum using these big parts (for example, SissySIT and Singing Bush). These Tokins are available (at least for now) and Mr Pass has warned that we should get them while we can.
The store's comment I believe was more about the Sony Vfets (2sk82/2sk28, etc)
The store's comment I believe was more about the Sony Vfets (2sk82/2sk28, etc)