Author Topic: Discrete TubeLess...  (Read 43793 times)

TELEFUNKON

Re: Discrete TubeLess...
« Reply #100 on: May 20, 2008, 03:30:27 AM »
Anyone tried these? Sound samples? Thanks in advance.  :)
grol

IIRC, there were some more or less crappy U2be clips earlier in this thread?
Obviously the OP has tried out some.

gaussmarkov

Re: Discrete TubeLess...
« Reply #101 on: May 20, 2008, 09:16:56 AM »
Seeing as this thread was revived, might as well give an update. 

Although RG's biasing was simpler, I reverted back to my original idea using feedback as part of the biasing.  Controlling closed-loop gain enabled me to contain things within the soft clipping zone.  Without it, there's a fine line before the amp is pushed into hard clipping (very unmusical as there's no gradual onset).  For a workable design a multistage circuit is required, plus a scope and signal generator.

Didn't build a circuit.  Unless CMOS chips go the way of the dodo, I'll stick with them as less work is required.

geez, gez, i was hoping for a better outcome.  this is really disappointing news, though a really appreciate that you have told us.

cheers, paul

p.s.  apologies for the cheap pull on your handle. :icon_twisted: :icon_wink:

gaussmarkov

Re: Discrete TubeLess...
« Reply #102 on: May 20, 2008, 09:26:00 AM »
I dug them out again for explanations in some other recent threads.

they`re interesting, but don`t reveal all questions:
FET principles & circuits pt.1,
pt.2,
pt.3,
pt.4, by the great Ray Marston.

Those N&V links don`t seem to work anymore
but excerpts are found here: http://www.uoguelph.ca/~antoon/tutorial/xtor/xtor10/xtor10.html

i have copies.  here are links:

FET principles & circuits pt.1,
pt.2,
pt.3,
pt.4, by the great Ray Marston.

puretube

Re: Discrete TubeLess...
« Reply #103 on: May 20, 2008, 01:26:49 PM »
Of course, I have a copy, too...
Just ain`t got no rights...

BTW: that "~antoon" link leads to some very nice stuff... Thanx!

gez

Re: Discrete TubeLess...
« Reply #104 on: May 20, 2008, 04:00:47 PM »
geez, gez, i was hoping for a better outcome.  this is really disappointing news, though a really appreciate that you have told us.

Paul, my comments refer to the JFET inverter idea.  Nothing wrong with it (sounded good), it's just that I personally don't see the point of building discrete circuits when there's an easier alternative: CMOS inverter chips.  The day they stop making these, then I'll start playing around with JFETs etc.

Quote
p.s.  apologies for the cheap pull on your handle. :icon_twisted: :icon_wink:

Consider me flushed!  :icon_lol:
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

gaussmarkov

Re: Discrete TubeLess...
« Reply #105 on: May 20, 2008, 06:15:59 PM »
geez, gez, i was hoping for a better outcome.  this is really disappointing news, though a really appreciate that you have told us.

Paul, my comments refer to the JFET inverter idea.  Nothing wrong with it (sounded good), it's just that I personally don't see the point of building discrete circuits when there's an easier alternative: CMOS inverter chips.  The day they stop making these, then I'll start playing around with JFETs etc.

ah, but you have given us a point already, haven't you?  :icon_wink:  an asymmetric version?  i haven't forgotten, because you scooped me on that one by several years.  :icon_biggrin: :icon_cool:

grolschie

Re: Discrete TubeLess...
« Reply #106 on: May 20, 2008, 06:19:38 PM »
What about the 170/250 MOSFET idea at the beginning of the thread?  ???  Or have I missed something?  :icon_redface:  Thanks in advance.  :)

puretube

Re: Discrete TubeLess...
« Reply #107 on: May 21, 2008, 07:56:45 AM »
Anyone tried these? Sound samples? Thanks in advance.  :)
grol

IIRC, there were some more or less crappy U2be clips earlier in this thread?
Obviously the OP has tried out some.

All "puretube`s" circuits, schemos and "crappy" sound-/video clips until reply#77 are tested, measured 170/250 builds...
(and the reason/origin for this thread explained in 1st post & reply#8)

One of the fine options of the WWW is the clickability of hyperlinx...  :icon_wink:

puretube

Re: Discrete TubeLess...
« Reply #108 on: August 08, 2008, 09:04:13 AM »
Anyone tried these? Sound samples? Thanks in advance.  :)
grol

IIRC, there were some more or less crappy U2be clips earlier in this thread?
Obviously the OP has tried out some.

All "puretube`s" circuits, schemos and "crappy" sound-/video clips until reply#77 are tested, measured 170/250 builds...
(and the reason/origin for this thread explained in 1st post & reply#8)

One of the fine options of the WWW is the clickability of hyperlinx...  :icon_wink:

Another fine free thing for all non-illiterates* is the socalled topic- or thread-title (aka: "subject"),
which in this special case says: "Discrete..." as opposed to: "integrated..."



As mentioned in above post,
an explanation for the experiments with 2 complementary discrete MOSFETS was given in reply#8,
and will be repeated in the following quote,
for those who don`t wanna look past the first pic in a thread:
... came up with this coz I didn`t have non-SMD inverters at hand to quickly view...


So it should be clear,
that this whole stuff was not about "emulating  tubes with fets",
but: "replacing a CMOS inverter IC with discrete MosFets"
(as far as my circuits are concerned).

And: it should also be clear by now, that those circuits are not an attempt
to make fets sound like tube-amps at all.
On the contrary:
I haven`t witnessed any (pure) tube-amp or (pure) tube-pedal outside my premises,
that would feature most of what those MosFet circuits do, soundwise...


*that come forum-crossing to this thread for the first time


pleez also see replies #24 & #38 for further understanding...