I have a set of Fairchild and Toshiba from F-5 building days but assumed the IRF/Vishay types would be used? Any advantage to the others?
Russellc
Russellc
If i remember correctly, the Fairchilds might yield slightly lower distortion, but I wouldn't worry too much either way. Wonderfully simple amp to build and bias.
4 boards for me please, any colour, preferably the cheapest.
Will there also be a GB for the transformers?
Will there also be a GB for the transformers?
The FQA give the more vivid punchy sound, the IRFs are more relaxed.
The transconductance of the N-type should be slowly higher.
The transconductance of the N-type should be slowly higher.
What the hey .... count me in for a pair of Green .....
Will there be a new thread in group buys? Didn't really see the details on how this is going to actually work!
Dave
Will there be a new thread in group buys? Didn't really see the details on how this is going to actually work!
Dave
What do you mean?
2 picoDumbs suggested to build a first prototyp before ordering a batch. German says: der Teufel steckt in Detail.
I´m still waiting for my first pair of PCB´s for my prototyp. Soldering, assembling and testing will bring me (it is a hobby) end of december before I can give some feedback.
Otherweise, I could start immediatly a M2 GB thread.
Jean-Paul
2 picoDumbs suggested to build a first prototyp before ordering a batch. German says: der Teufel steckt in Detail.
I´m still waiting for my first pair of PCB´s for my prototyp. Soldering, assembling and testing will bring me (it is a hobby) end of december before I can give some feedback.
Otherweise, I could start immediatly a M2 GB thread.
Jean-Paul
I have no problem waiting for tested version, always best way to proceed. When ever done I will still take stereo set.
Russellc
You remember Nelson hints for the output pair matching….?
if not look here
http://www.diyaudio.com/forums/pass-labs/281520-official-m2-schematic-6.html#post4495215
Because I was a bit irritated he was so friendly to give me an "extended version"…… THX Nelson!
"The numbers are get have about 1 volt more Vgs (about 5V) for P channel FQA12P20
vs about 4V for FQA19n20c at 1 amp (cold). That is why you see the trim pot on the
top side for the DC offset.
"The transconductance of the N type is a little higher, but in practice I see a consistent
3rd harmonic character, so it’s not much higher.
There are better parts out there, although my favorites would be the Toshiba 2SK1530
and 2SJ201. If you look them up you will see why, but they are discontinued."
hope sharing Nelsons words is no sacrilege in this case….. 🙂
if not look here
http://www.diyaudio.com/forums/pass-labs/281520-official-m2-schematic-6.html#post4495215
Because I was a bit irritated he was so friendly to give me an "extended version"…… THX Nelson!
"The numbers are get have about 1 volt more Vgs (about 5V) for P channel FQA12P20
vs about 4V for FQA19n20c at 1 amp (cold). That is why you see the trim pot on the
top side for the DC offset.
"The transconductance of the N type is a little higher, but in practice I see a consistent
3rd harmonic character, so it’s not much higher.
There are better parts out there, although my favorites would be the Toshiba 2SK1530
and 2SJ201. If you look them up you will see why, but they are discontinued."
hope sharing Nelsons words is no sacrilege in this case….. 🙂
I went to the basement and…… 🙂
leftover from F5 experiments in 2008 with F5
for German colleagues possibly interesting…more leftovers
https://www.csi-elektronik.de/2SJ201-J-Transistor
2SK1530
leftover from F5 experiments in 2008 with F5
for German colleagues possibly interesting…more leftovers
https://www.csi-elektronik.de/2SJ201-J-Transistor
2SK1530
