Twitchie, I just noticed the drawing of 2sk370 is backwards, drain should go towards the + rail and source to ground. No big deal, the traces look fine.
If you make more boards you could also run the 240 source trace down the edge of the board and over to the .47 res. Then you could eliminate the drain jumper too, and just place the gate res across it.
Bill
If you make more boards you could also run the 240 source trace down the edge of the board and over to the .47 res. Then you could eliminate the drain jumper too, and just place the gate res across it.
Bill
I don't see why not. My old JX-92 based speaker was used with a variety of high and low quality amplifiers, but never more than 50 watts.
C
C
I just moved the Jx92 mltl in my new apartament and I am wondering
what amp to build around them .... 😎
what amp to build around them .... 😎
Mine were in small sealed cabinets.
The best sound I ever heard with them was with the Air Tight 300b amplifier, but that was borrowed.
The best sound I ever heard with them was with the Air Tight 300b amplifier, but that was borrowed.
I am currently using the Fostex fe206 , so I am indecided if build a new pair of MLTL with the 166 ... or try something new for the JX92s
Thanks for all the kind words and words of encouragement. I just started a new job this week, so finding time to get back to this has been difficult.
about the drilling - I must be getting the cheap drill bits around here, or I must be overly aggressive in drilling because I always manage to snap my last one (doesn't matter how many backups I buy) before I finish all the holes
Murphy's law rules around here with an iron fist (fist reference was not intentional). Another case in point - I pull my Proac clones apart to finally veneer them after running them 'au naturel' for years, and end up getting delayed by having my hex-head wood screw order lost by Canada Post ...
about the drilling - I must be getting the cheap drill bits around here, or I must be overly aggressive in drilling because I always manage to snap my last one (doesn't matter how many backups I buy) before I finish all the holes
Murphy's law rules around here with an iron fist (fist reference was not intentional). Another case in point - I pull my Proac clones apart to finally veneer them after running them 'au naturel' for years, and end up getting delayed by having my hex-head wood screw order lost by Canada Post ...
An externally hosted image should be here but it was not working when we last tested it.
GR, BL, V?
So, which of the 2SK170/2SJ24 versions is more suited to the F5 schematic as proposed, GR, BL or V? I know this is a silly question but to tell the truth, its the first time I am dealing with Jfets and I am getting a little confused here.
I am sure that Mr. Pass specified everything (as usual) in his article in AudioXpress, but in this part of the world the May issue is not yet available and I am already gathering parts...
Thanks
So, which of the 2SK170/2SJ24 versions is more suited to the F5 schematic as proposed, GR, BL or V? I know this is a silly question but to tell the truth, its the first time I am dealing with Jfets and I am getting a little confused here.
I am sure that Mr. Pass specified everything (as usual) in his article in AudioXpress, but in this part of the world the May issue is not yet available and I am already gathering parts...
Thanks
I made a mistake which Ole pointed out, the schema is changed to reflect the correct S and D connections.
Here's a 3D hypothetical using some Caddock TO-220 feedback resistors which will attach to the heat sink:
Here's a 3D hypothetical using some Caddock TO-220 feedback resistors which will attach to the heat sink:
An externally hosted image should be here but it was not working when we last tested it.
Re: GR, BL, V?
You want to test Idss for 8+ ma current with the Gate and Source
shorted and Vds at 10V.
BL is the preferred part, but you can use GR if you raise the
Drain resistance. Currently its a 5K pot, in parallel with a thermistor
plus 2.2K in parallel with a 2.2K. You can remove the 2.2K.
Alternatively you can consider paralleling JFETs to get the current up.
panos29 said:
You want to test Idss for 8+ ma current with the Gate and Source
shorted and Vds at 10V.
BL is the preferred part, but you can use GR if you raise the
Drain resistance. Currently its a 5K pot, in parallel with a thermistor
plus 2.2K in parallel with a 2.2K. You can remove the 2.2K.
Alternatively you can consider paralleling JFETs to get the current up.
Re: GR, BL, V?
Taking the risk to appear publicly too stupid…
Why V grade with a lower R wouldn’t work?
I'm afraid that it would reduce the open loop gain, but the same goes for GR the other way round (I mean increase the OLG with GR).
Best regards.
Philippe.
Nelson Pass said:
Taking the risk to appear publicly too stupid…
Why V grade with a lower R wouldn’t work?
I'm afraid that it would reduce the open loop gain, but the same goes for GR the other way round (I mean increase the OLG with GR).
Best regards.
Philippe.
jacco vermeulen said:
So you're offering a group buy od 2sk147 😀
The answer to your question may be due to Jaccolina😎 or the lack of
Magura 🙂
Re: Re: GR, BL, V?
Good question. The amp will work fine with V. I neglect it for two
reasons.
1) try and find any, and if you do, save them for phono stages 🙂
2) I want to limit the current to about 8 ma through the circuit to
avoid too much dissipation in the JFET. Of course you can use a
greater value than the 10 ohm for the feedback, but you can
just as easily get by with a BL.
plep said:
Good question. The amp will work fine with V. I neglect it for two
reasons.
1) try and find any, and if you do, save them for phono stages 🙂
2) I want to limit the current to about 8 ma through the circuit to
avoid too much dissipation in the JFET. Of course you can use a
greater value than the 10 ohm for the feedback, but you can
just as easily get by with a BL.