How about 50uF Black Gate non-polar?
Concerning a large by-pass for the J2's supply caps -
These have two advantages for me:
1. I have them
2. They are small
Dear Zen Mod and other interested parties,
What do you think? Would this be just as good as the motor runs or not worth the trouble?
I know, I know, I should try it and see, but I do not want to fiddle around with the amplifier too much and take a chance at doing something stupid, AND even more importantly, I am lazy.
All comments would be appreciated.
THANKS,
Concerning a large by-pass for the J2's supply caps -
These have two advantages for me:
1. I have them
2. They are small
Dear Zen Mod and other interested parties,
What do you think? Would this be just as good as the motor runs or not worth the trouble?
I know, I know, I should try it and see, but I do not want to fiddle around with the amplifier too much and take a chance at doing something stupid, AND even more importantly, I am lazy.
All comments would be appreciated.
THANKS,
🙂
BG is BG , but big film cap is big film cap .
somehow I know where my preference is , at least in PS
A rose is a rose is a rose ...
and never the twain shall meet? (can mixed literary references be comedic and true?)
That kind of thing?
I will get some large film caps and report.
Thanks,
and never the twain shall meet? (can mixed literary references be comedic and true?)
That kind of thing?
I will get some large film caps and report.
Thanks,
Since the J2 shows predominantly 2nd harmonic, can we build a X-ed (fully balanced) J2 and finish with much lower total distortion?
Of course that will be 4X the power, 4X the cost.
Of course that will be 4X the power, 4X the cost.
Zhoufang, have you thaught how much such a beast would cost to build?
That thing would need some realy HUGE heatsinks and would probably need
16 of those hard to get $60 jfets that would come to ~$1000 just for the
jfets alone! Now that jfet does come in a higher disipition model the sjep120r063
and if you could get us some of those for a reasonable price I sure would like a few!
That thing would need some realy HUGE heatsinks and would probably need
16 of those hard to get $60 jfets that would come to ~$1000 just for the
jfets alone! Now that jfet does come in a higher disipition model the sjep120r063
and if you could get us some of those for a reasonable price I sure would like a few!
yes , we certainly can ; in same manner as Aleph X is made from Aleph , and Aleph XJ is made from Aleph J - core is common LTP for two output sides .
note that some ppl certainly don't need that much power , and that some ppl prefer predominantly 2nd harmonic
Considering each r063 is equal to two R125/R100, we will be buying half as many r063 as we would r100 (that is not counting those who feel a single r063 is too expensive).
And r063, at half the quantity of r100, will cost 3X per unit compared to r100, due to semisouth's very steep price cut for qty.
I'm the the process of making an order with semisouth, if successful, you can expect unit price a little lower than the GB price, matched, plus further volume discount if you get 16 for an x amp, and stock available in late June (long lead time + sorting).
Not really, you can expect 16 of these to cost under $600.
I hope that will make a difference.
Except that J2 does not used a Aleph current source, or else we might just drop the JFET into AX PCB.
The good part of an X to me is that you make full use of the other half side P-JFET (j109, j74) LTP, especially in a design like J2, which you need to parallel the input-stage JFET but not the output-stage one!
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Zen Mod:
I said that sentence just to express how I wish J2-X could just use the A-X PCB and still get the full SiC JFET benefit.
I said that sentence just to express how I wish J2-X could just use the A-X PCB and still get the full SiC JFET benefit.
🙂
considering all expenses needed for X amp (mainly hardware bits 'n' pieces , but this time even tube-like prices for outputs ) , I think that pcbs are minor problem .
I believe that this issue will be solved in meantime , while you get your batch of silly critters
You can drop the JFET into the Aleph circuit, it's just that I
found the mu follower to operate a little better with the lower
Vgs. Not a big deal. You can easily adapt the board in any case
with the npn as the voltage reference.
😎
I've got a channel of an Mini-A working with these JFETs. Only changes so far was getting the R8 up a bit to deal with DC offset.
I want to try next with BA-1 boards.😀
Hmm, what do you want to know? R8 was about 680R.
I could not get in too easily to measure current/Voltages on the IRF610's. No idea what to swap around for ideal parts here, it's otherwise a default unbalanced Mini-A. I figured the Mini-A could take more current in the front end it will make it sound better.
The VGS are about 1.2-6v to conduct on these critters (SS-JFet).
I will try to get back to it at some point. Got distracted by a guy who sent me Little Toshiba's to complete yet another F5 variant. 🙂
I could not get in too easily to measure current/Voltages on the IRF610's. No idea what to swap around for ideal parts here, it's otherwise a default unbalanced Mini-A. I figured the Mini-A could take more current in the front end it will make it sound better.
The VGS are about 1.2-6v to conduct on these critters (SS-JFet).
I will try to get back to it at some point. Got distracted by a guy who sent me Little Toshiba's to complete yet another F5 variant. 🙂
Between an regular A-X (using 3 parallel 240 or 044 per quad) and an proper j2-x (2x semisouth R100 per quad), can we still expect the J2-x to have an edge on open loop distortion?
Nelson often state the 5 second rule for heatsink temperature.
With SiC device (or rather their epoxy packaging) rated for 175degC, as compared to 125degC for silicon, isn't a good reason for us to accept a higher heatsink temperature? (while maintaining enough thermal gradient between the heatsink and the junction)
So except for consumer protection (since "CAUTION: HOT!" are not written on the heatsink), is there any reason stopping us from saving half the size of heatsink, and just let it get hotter?
With SiC device (or rather their epoxy packaging) rated for 175degC, as compared to 125degC for silicon, isn't a good reason for us to accept a higher heatsink temperature? (while maintaining enough thermal gradient between the heatsink and the junction)
So except for consumer protection (since "CAUTION: HOT!" are not written on the heatsink), is there any reason stopping us from saving half the size of heatsink, and just let it get hotter?