Late to the party and still can’t quite believe I have one of these! Finally got all the bits needed to complete the essentials kit I managed to snag online at BA22 and built it the next day.
Sounds wonderful into 93db floorstanders. Like others have commented, excellent bass and sometimes it can sound downright spooky!
Thanks Papa, this is special. And thanks to all who made getting it possible.
Sounds wonderful into 93db floorstanders. Like others have commented, excellent bass and sometimes it can sound downright spooky!
Thanks Papa, this is special. And thanks to all who made getting it possible.
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I use it daily and I am very pleased. I am very curious what would happen with a "better" power supply than the included brick. I have thought about upgrading for a long time. Maybe the universal power supply from the diyaudio store will have nicer looking sinus waves, I don't know. The connector is somewhat confusing for novices with so many pins, and I don't know what precautions to take when building a new PSU.
A relatively simple thing to try is adding a 1000 uF or 2200 uF, 50V cap between the power rails on each channel, right where the wiring is attached. The brick SMPS handles these values without any problem. If you like what you hear (give it a good 20 hours to settle in), consider whether you are willing to go further.
This mod has really good bang for the buck and is easy to back out if you are unconvinced about the improvement.
This mod has really good bang for the buck and is easy to back out if you are unconvinced about the improvement.
I bought two Panasonic 1500uF caps to try just the above. And left enough cable protruding on the rails to easily add them. Going to listen to it as Papa intended for a few weeks then add the caps and see. No hurry. I quite like the connector and bought two matching male ends - in case I indulge the itch we all have, as proper diy’ers, to see if there’s any benefit to a different power supply 🙃!
ZM - turned on the amp and fired up the multimeter's temp measurement. It said the ambient temp was 33 degrees C - it IS a hot day but that seemed about 3-4 degrees too hot but who knows....
After an hour playing music with the cover resting in place I removed the cover and measured the VFETs: 61 degrees each. MOSFETS were about 3-4 degrees less. Center between the TO3's was 50 degrees
Outside of heatsink - closest to T-Bar center (i.e, not on fins): 53 degrees C. Fins around 45 degrees. PS case 40 degrees.
Incidentally, the old Craftsman IR 'pistol' I have reads about 16 degrees lower. But was consistent. Those devices should come with a warning!
Rested cover back on and shall measure again when the music lets me remember....
After an hour playing music with the cover resting in place I removed the cover and measured the VFETs: 61 degrees each. MOSFETS were about 3-4 degrees less. Center between the TO3's was 50 degrees
Outside of heatsink - closest to T-Bar center (i.e, not on fins): 53 degrees C. Fins around 45 degrees. PS case 40 degrees.
Incidentally, the old Craftsman IR 'pistol' I have reads about 16 degrees lower. But was consistent. Those devices should come with a warning!
Rested cover back on and shall measure again when the music lets me remember....
If anyone wants some more Edcor PC600-15K transformers, as used in the Sony VFET front ends {including Scourge and Bulwark}, I'm giving away a set of nine of them for free (but you pay $17 postage). And you have to un-solder them from obsolete PCBs. Here is a link to the message in the Swap Meet.
I built my lottery vfet (no mods, pure stock) a few years ago and loved it. It was powering a pair of Avalon Studio Pro monitors, and it sounded gorgeous, although it lacked a bit in the bass and did run out of steam when turned up. I was not using a preamp and was feeding it direct from a 2V unbalanced source, so with only 10dB gain I was not surprised it could not play loud, but loved it enough to put up with the limitations.
When one of the tweeters in the speakers stopped working, I switched to an old pair of Avalon Arcus floorstanding speakers, and this was too much for the vfet, so I switched to the J2 I built some years before. Still no preamp, but I was now able to use the 3V balanced output from the source and with the higher gain from the J2 it is more than loud enough. I have since tried a few different power amps, but the J2 keeps coming back!
By the time the tweeter of the Avalon monitor was repaired I had just finished the H2. With the H2 between the 2V unbalanced source and the vfet, I had enough gain and was no longer lacking bass. A great combo.
I had my old Magnepan MG3A's rebuilt by the factory some time ago. I have had them for 25 years and always ran them biamped with the same preamp (Jeff Rowland Consummate) and power amps (Aleph 3 for mid/high and Plinius 8200P MkII for bass). The Aleph 3 amplifies the full signal and the bass amp takes the bass output from a Behringer crossover (running the Aleph 3 from the mid/hi outputs of the Behringer sounds awful). [one day I'll build the diy crossover haha]
My preamp stopped working about 5 years ago and replacements (incl. a diy Aleph P1.7) never gave me the sound I wanted. I recently (finally) got the Consummate preamp working again (see my cautionary thread on leaky capacitors) and it is back to it's glorious self. I hooked it up in the old configuration (but now using an F5 for bass instead of the Plinius) and finally have the sound back I had missed for so long.
But ...
Although the vfet only output 5W into 4Ohm, I thought I would try the vfet to power mid/hi of the magnepans on Wednesday (replacing the Aleph 3). My recently recapped preamp was set for 6dB and my crossover needed quite a bit of adjustment to cope with the lower gain of the vfet, but even though it could not play loud, it was the best I ever heard. Today, I changed the preamp gain to 18dB and am amazed at the soundstage the little vfet is able to project through/on the magnepans.
I have a pair of diy F4s so an obvious experiment is going to be to try the vfet in combination with the F4s. Not sure when that will happen though, because I am enjoying just having the vfet powering the mid/hi of the magnepans so much!
And then there are possible the vfet mods that others have described …
When one of the tweeters in the speakers stopped working, I switched to an old pair of Avalon Arcus floorstanding speakers, and this was too much for the vfet, so I switched to the J2 I built some years before. Still no preamp, but I was now able to use the 3V balanced output from the source and with the higher gain from the J2 it is more than loud enough. I have since tried a few different power amps, but the J2 keeps coming back!
By the time the tweeter of the Avalon monitor was repaired I had just finished the H2. With the H2 between the 2V unbalanced source and the vfet, I had enough gain and was no longer lacking bass. A great combo.
I had my old Magnepan MG3A's rebuilt by the factory some time ago. I have had them for 25 years and always ran them biamped with the same preamp (Jeff Rowland Consummate) and power amps (Aleph 3 for mid/high and Plinius 8200P MkII for bass). The Aleph 3 amplifies the full signal and the bass amp takes the bass output from a Behringer crossover (running the Aleph 3 from the mid/hi outputs of the Behringer sounds awful). [one day I'll build the diy crossover haha]
My preamp stopped working about 5 years ago and replacements (incl. a diy Aleph P1.7) never gave me the sound I wanted. I recently (finally) got the Consummate preamp working again (see my cautionary thread on leaky capacitors) and it is back to it's glorious self. I hooked it up in the old configuration (but now using an F5 for bass instead of the Plinius) and finally have the sound back I had missed for so long.
But ...
Although the vfet only output 5W into 4Ohm, I thought I would try the vfet to power mid/hi of the magnepans on Wednesday (replacing the Aleph 3). My recently recapped preamp was set for 6dB and my crossover needed quite a bit of adjustment to cope with the lower gain of the vfet, but even though it could not play loud, it was the best I ever heard. Today, I changed the preamp gain to 18dB and am amazed at the soundstage the little vfet is able to project through/on the magnepans.
I have a pair of diy F4s so an obvious experiment is going to be to try the vfet in combination with the F4s. Not sure when that will happen though, because I am enjoying just having the vfet powering the mid/hi of the magnepans so much!
And then there are possible the vfet mods that others have described …
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