Current flowing through the Zener Z1 is expected have a low value; maybe in the uA range; so as to generate the joint [ -Vgs] to DEFiSIT or DEF. This Zener current flows from the output through the autoformer and terminates at the joint sources of the input buffer JFETs. Too high a Zener current may "magnetize' the autoformer and cause sonic heartburn as I recall from the work of lhquam on diyF6. Maybe the Cinemag autoformer does not care about this potential problem of DC continually flowing through it!.
more than enough candidates ........ but none of them really counter-candidates , each having own flavor and virtues
Babelfish J , Babelfish J2 , M2 .... name it ...... I can't really pick ;
list of amps in which I wasn't so personally interested is even longer
catch is - my speakers are pretty benign , regarding drive , so I can enjoy amps with finesse even if price (for finesse) is having them in corner reserved for wimpier ones
anyway , M2 and DEFiSIT - close cousins , M2 being more all-rounder (50W/4R is decent , if you ask me)
almost forgot ..... I'll see (hear) hopefully soon what's going on with Babelfish XA25
edit: of course that each one - classified as Papa's Koan , is personal gift ...... be it complete (real , physical) amplifier , or "just" files ..... is absolutely priceless and incomparable
Joie de vivre
further explanation of phenomenon absolutely redundant
Babelfish J , Babelfish J2 , M2 .... name it ...... I can't really pick ;
list of amps in which I wasn't so personally interested is even longer
catch is - my speakers are pretty benign , regarding drive , so I can enjoy amps with finesse even if price (for finesse) is having them in corner reserved for wimpier ones
anyway , M2 and DEFiSIT - close cousins , M2 being more all-rounder (50W/4R is decent , if you ask me)
almost forgot ..... I'll see (hear) hopefully soon what's going on with Babelfish XA25
edit: of course that each one - classified as Papa's Koan , is personal gift ...... be it complete (real , physical) amplifier , or "just" files ..... is absolutely priceless and incomparable
Joie de vivre
further explanation of phenomenon absolutely redundant
Last edited:
Most interesting and creative solution to generate -Vgs to bias DEF and/or DEFiSIT. What I also find technically astounding for DEFiSIT is that a triode-like and a pentode-like devices are working together[cleanly] in push-pull mode. The electrical characteristics of a SIT and a P-MOSFET are very different!well , I understand it as I wrote , zener being limiting device , to not exceeding GS voltage , for both parts in same time
is this time for another e-mail to Papa , to ask him ?
I hope that Mr. Pass will in due time explain the Zener circuit to generate -Vgs, and other charms of DEF and DEFiSIT.
Best
Anton
Z1 is simply protection. With xfrmr for gain stage is possible to come up
with enough voltage to break Jfet or Mosfet. It will not be conducting in
normal use.
Z2, Z3 and Led are just to make a voltage to use for offset adjust. I have
lots of 9.1 zeners in boxes, so I set it up for multiples of 9.1. However, power
supply was too low to bias 3 of them (27.3V plus) and 18.2 was too low
for operation, so I used a Led to put me in between.
If I were to lay this circuit out again, I would put adjustable TL431 in their
place....
with enough voltage to break Jfet or Mosfet. It will not be conducting in
normal use.
Z2, Z3 and Led are just to make a voltage to use for offset adjust. I have
lots of 9.1 zeners in boxes, so I set it up for multiples of 9.1. However, power
supply was too low to bias 3 of them (27.3V plus) and 18.2 was too low
for operation, so I used a Led to put me in between.
If I were to lay this circuit out again, I would put adjustable TL431 in their
place....
entire biasing current , demanded by output's gates , including AC modus demands , is delivered through xformer winding ;
currents are minuscule in DC realm , little bigger when swing rises , but nothing to write home about
consider that those xformers aren't small piglets made for MC signal , but classic PA jobbies , made to withstand serious abuse
their job in M2 and DEFiSIT is trivial , regarding seriousness of loading
so , diode isn't wodoo part here ; omit it and everything will work the same , as long nasty spikes are far from gates
edit : he's faster ,again ........ typed in same time
currents are minuscule in DC realm , little bigger when swing rises , but nothing to write home about
consider that those xformers aren't small piglets made for MC signal , but classic PA jobbies , made to withstand serious abuse
their job in M2 and DEFiSIT is trivial , regarding seriousness of loading
so , diode isn't wodoo part here ; omit it and everything will work the same , as long nasty spikes are far from gates
edit : he's faster ,again ........ typed in same time
ZM > anyway , M2 and DEFiSIT - close cousins ..
Similar and different beacause Pass SIT-1 and Cinemag etc.
M2 without input and output capacitors.
Curious about Your first music play with DEFiSIT
Similar and different beacause Pass SIT-1 and Cinemag etc.
M2 without input and output capacitors.
Curious about Your first music play with DEFiSIT
Attachments
naah .... too common and too simple
LED string ( 3mm greens and MMBF5486) is so much more fun
I'm a fan of Primus "Have a cigar"
" Frizzle Fry is the debut studio album of Primus, recorded in 1989 for Caroline Records.
Frizzle Fry
TRACK LISTING:
[0:00] "To Defy the Laws of Tradition"
[6:38] "Ground Hog's Day"
[11:29] "Too Many Puppies"
[15:34] "Mr. Know It All"
[19:25] "Frizzle Fry"
[25:32] "John the Fisherman (Fisherman Chronicles, Chapter I)"
[29:10] "You Can't Kill Michael Malloy"
[29:35] "The Toys Go Winding Down"
[34:10] "Pudding Time"
[38:19] "Sathington Willoby"
[38:44] "Spegetti Western"
[44:27] "Harold of the Rocks"
[50:45] "To Defy"
Funny "To Defy the Laws of Tradition" and " To Defy " songs.
to ZM build DEFiSIT
Frizzle Fry
TRACK LISTING:
[0:00] "To Defy the Laws of Tradition"
[6:38] "Ground Hog's Day"
[11:29] "Too Many Puppies"
[15:34] "Mr. Know It All"
[19:25] "Frizzle Fry"
[25:32] "John the Fisherman (Fisherman Chronicles, Chapter I)"
[29:10] "You Can't Kill Michael Malloy"
[29:35] "The Toys Go Winding Down"
[34:10] "Pudding Time"
[38:19] "Sathington Willoby"
[38:44] "Spegetti Western"
[44:27] "Harold of the Rocks"
[50:45] "To Defy"
Funny "To Defy the Laws of Tradition" and " To Defy " songs.
to ZM build DEFiSIT
World première next innovation from Mr Pass
It's first time in the history of solid state amplification!
Yes extraordinary !! Congratulations !!
post scriptum : ZM know he is lucky one
Attachments
