For whatever reason, and I'm honestly not sure why, F5m sounds better than the original. (Though both sound great.)
You can still make F5m with those PCB, it’s simpler and more straightforward, though there really isn’t a wrong answer at all.
You can still make F5m with those PCB, it’s simpler and more straightforward, though there really isn’t a wrong answer at all.
Post both schematics here… the original F5 (which is going to not have P3) and the current F5m and see if we can figure it out.
I've got a printed f5 schematic that I'm red markering. The part I'm working on right now is Q1 Q2, on the f5m the sources are together, which goes to R5 on the f5m, but to ground through 10r on the f5. I think my first major change is I'm going to have to cut that ground trace.
I can't find the f5 schematic that I have on paper here, but it's the same one that's in the illustrated build pic that says "figure 6 f5 amplifier" at the bottom of it.
Edit oh wait, can i just jumper the two sides of r1 and r2 to r5 and r6..
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But of course you can build one channel of F5, and another of F5m, using the same PCBs and Q-set.
Play them against each other in mono.
Then decide which one you prefer, and modify the other one to make a pair.
Every person would have a different preference.
You cannot reply on others to decide for you.
🙂
Patrick
Play them against each other in mono.
Then decide which one you prefer, and modify the other one to make a pair.
Every person would have a different preference.
You cannot reply on others to decide for you.
🙂
Patrick
I have an f5m of my own that I built, I got into this f5 project for a friend, who had 2 sets of boards.
Thanks guys, that edited schematic is exactly what I needed!
Oh, one last thing I should mention, I'm assuming that it's going to work fine, but these F5 parts I got for this kit has the Toshiba output fets, 2sj201 vs irfp9140 and 2sk1530 vs irfp240.
I'm still good to go with these on the f5m, but just in case ..
I'm still good to go with these on the f5m, but just in case ..
Assume you bias at 1.3A.
Voltage across 0R47 is 0.6V.
Vgs for the Toshiba's is typically 2.4 V.
So 3V in total.
Assume JFET Idss at 8 mA.
Drain resistor should be 375R.
More like 500R trimmer than 2k.
Don't you think ? 😉
Patrick
Voltage across 0R47 is 0.6V.
Vgs for the Toshiba's is typically 2.4 V.
So 3V in total.
Assume JFET Idss at 8 mA.
Drain resistor should be 375R.
More like 500R trimmer than 2k.
Don't you think ? 😉
Patrick
We’re talking about the output mosfets.
I’ve never used the output Toshibas, would absolutely love to, just never had the chance to get any, and my recollection (which may be incorrect, of course) is people needed bigger pots.
But that is memory, and this is a 15yr old project at this point, so details may be fuzzy.
Of only 500R is needed, then the 1K will work beautifully.
I’ve never used the output Toshibas, would absolutely love to, just never had the chance to get any, and my recollection (which may be incorrect, of course) is people needed bigger pots.
But that is memory, and this is a 15yr old project at this point, so details may be fuzzy.
Of only 500R is needed, then the 1K will work beautifully.