What a great contribution to the diy crowd! This may be possibly the new Swiss army knife line stage circuit I was looking for. Many thanks to you Mr Pass for this!
Hmmm, I have a stack of J113s. This looks like it could be a very useful balanced line converter, RIAA or output buffer for eq and active xover.
Any precautions one could take to safeguard the fets in case of input without B+ present? How close do the input fets need to be matched?
Hmmm, I have a stack of J113s. This looks like it could be a very useful balanced line converter, RIAA or output buffer for eq and active xover.
Any precautions one could take to safeguard the fets in case of input without B+ present? How close do the input fets need to be matched?
if you need to ask, take care to observe presented schm as Black Box;
whatever you want to add, it goes either in front of Black Box, or after Black Box
so, in short - No.
Volume pot goes in front of Black Box
main reason - R1 is defining part of circuit, gain wise and impedance wise; R3 also being important ........... and - in case of resorting to single rail arrangement, there is substantial DC potential across R3
whatever you want to add, it goes either in front of Black Box, or after Black Box
so, in short - No.
Volume pot goes in front of Black Box
main reason - R1 is defining part of circuit, gain wise and impedance wise; R3 also being important ........... and - in case of resorting to single rail arrangement, there is substantial DC potential across R3
Nelson Pass has got a point - J113 is plenty to buy.
It often comes down to if we can find and buy.
Otherwise not anybody can build.
It often comes down to if we can find and buy.
Otherwise not anybody can build.
2sk369 fits that bill handsomely.
the only problem for most folk might be it is even harder to find than 2sk170
So for transformer drive... replace R5 with a jumper? (FE will be near load) Make C3 100X bigger? Crank the output current to ~15mA and don't put your tongue on Q4,Q5? 😛 (I have some little clip-on heatsinks)I vote for that.
How are the values of the resistors for the J113 determined?
=> R7, R8 matched to Vp of J113
Anyone have an explanation?
thanks
(If you don't ask, you remain stupid!) 😕
=> R7, R8 matched to Vp of J113
Anyone have an explanation?
thanks
(If you don't ask, you remain stupid!) 😕
Depending on voltage, 15mA could be a little excessive.
You might get away with it with heatsink attached.
Currently my rails are 22.7V. I thought about doing a CLC with active bridge later that will bring the rails up quite a bit. I guess you get into needing to parallel some more outputs or something.... Would be nice to see a schematic of how to do this properly...
Good possibility!
2SK3557 - JFets do a very good sounding job in two of my WaynesLineStage-variants. But max. voltage rating D-S of 2SK3557 is much lower (15 V max) than J113. Cascoding to the rescue?
No. The J113 can do a really great sounding job! Pretty cheap and available.
Greets
Dirk
2SK3557 - JFets do a very good sounding job in two of my WaynesLineStage-variants. But max. voltage rating D-S of 2SK3557 is much lower (15 V max) than J113. Cascoding to the rescue?
No. The J113 can do a really great sounding job! Pretty cheap and available.
Greets
Dirk
Watanabe san has them, though V grade. I bought a batch and measured Idss was in 18 - 20 mA range.
2SK369V
