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Prune Prune is offline
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Default Need EL34 grounded-grid curves

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven operation
anywhere. Help would be greatly appreciated!
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Default Need EL34 grounded-grid curves

I forgot to mention it's for a triode-connected EL34.


Prune wrote in
4.76:

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven operation
anywhere. Help would be greatly appreciated!


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Default Need EL34 grounded-grid curves

Also forgot to add it's for under constant current operation; I need plate
voltage vs cathode voltage.

If such data can't be found, is there a way I can derive it from other
curves?


Prune wrote in
4.76:

I forgot to mention it's for a triode-connected EL34.


Prune wrote in
4.76:

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven operation
anywhere. Help would be greatly appreciated!




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Phil Allison Phil Allison is offline
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Default Need EL34 grounded-grid curves


"Prune"

Also forgot to add it's for under constant current operation; I need plate
voltage vs cathode voltage.

If such data can't be found, is there a way I can derive it from other
curves?



** The basic plate current V negative grid voltage curves still apply.

Just that with cathode drive, the varying negative grid voltage is actually
a varying positive cathode voltage ( all voltages relative to chassis).

The whole game ( linearity wise) depends on the performance of the actual
scheme used for driving the cathodes - ie how accurately does it convert
the input signal voltage to proportional changes in cathode current.

How about you describe yours ?




........ Phil




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Default Need EL34 grounded-grid curves

Hi Phil,

My question is due to the fact that I need to cut down the power drawn
by the electrostatic headphone hybrid amp I've asked about previously on
this group. I didn't talk about the amplication in my initial post
since I didn't want people to start discussions about the amp not
relating to my question; I've already built the amp and I need to change
operating point.

http://www.headwize.com/images5/gilmore4_1.png

Ignoring all but the output stage, V1/2 Q8/15

The designer claimed he had chosen operating point so that the tube's
non-linearity in this configuration was roughly canceled by the driving
source follower's nonlinearity.

My problem is I have to reduce power supply voltage and current a bit.
When I built the power supply transformer, I didn't realize that I
should give it enough margin voltage so that as my mains voltage varies
(up to 10% in my house, even if rarely), the raw supply could drop below
the power regulator's voltage.

So my concern is how much to cut the idle current by when I reduce
supply voltage by a given amount, so as to preserve the rough inverse
matching of the nonlinearities of the two devices. Or do I change the
operating point of the MOSFETs instead. The reason I wanted to see the
curves is to compare how the nonlinearity changes with varying the
voltage and current through the tube.

My aim here is to retain the 40 ppm THD measured with the original while
just reducing the power of the amp (it's kind of overkill since 1500 V
peak to peak drives the Stax a good deal louder than I'd normally listen
to).

Thanks.



"Phil Allison" wrote in
:


"Prune"

Also forgot to add it's for under constant current operation; I need
plate voltage vs cathode voltage.

If such data can't be found, is there a way I can derive it from
other curves?



** The basic plate current V negative grid voltage curves still apply.

Just that with cathode drive, the varying negative grid voltage is
actually a varying positive cathode voltage ( all voltages relative to
chassis).

The whole game ( linearity wise) depends on the performance of the
actual scheme used for driving the cathodes - ie how accurately does
it convert the input signal voltage to proportional changes in cathode
current.

How about you describe yours ?




....... Phil







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Default Need EL34 grounded-grid curves

I'm guessing I can use the XY plotting on a scope to do this somehow. But
what do I feed the tube, a triangular wave or something?


"Bret Ludwig" wrote in news:1174973043.127493.34070
@n59g2000hsh.googlegroups.com:

You are going to have to build a test fixture and plot them.


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Default Need EL34 grounded-grid curves



Prune wrote:

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven operation
anywhere. Help would be greatly appreciated!



The grounded grid curves are the same as for grounded cathode in either
pentode, UL or triode.

Voltage gains are indentical.

All that changes is the input impedance which is high for grounded
cathode, and very low for
grounded grid, and Rk in = RL / voltage gain.

There are no separtae groups of curves for grounded grid.

Musicman guitar amps used transistors to drive the cathodes of output
tubes,
and this could have been a reason why they went out of business.

Patrick Turner.
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Default Need EL34 grounded-grid curves

Thanks, I guess that answers that question. Now if I could only find
curves for the MOSFET. The datasheet only has current vs voltage ones.


Patrick Turner wrote in news:4608C3FE.2DCAD8A1
@turneraudio.com.au:



Prune wrote:

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven operation
anywhere. Help would be greatly appreciated!



The grounded grid curves are the same as for grounded cathode in either
pentode, UL or triode.

Voltage gains are indentical.

All that changes is the input impedance which is high for grounded
cathode, and very low for
grounded grid, and Rk in = RL / voltage gain.

There are no separtae groups of curves for grounded grid.

Musicman guitar amps used transistors to drive the cathodes of output
tubes,
and this could have been a reason why they went out of business.

Patrick Turner.


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Default Need EL34 grounded-grid curves



Prune wrote:

Thanks, I guess that answers that question. Now if I could only find
curves for the MOSFET. The datasheet only has current vs voltage ones.


But what current and what voltage at what electrodes?

Mosfet data should appear like pentode data, ie with Id plotted on a
vertical
scale and Ed horizontally, and the curves you see are Rd curves at
various values
of Egate.

But you have a PP circuit, and wishing for complementary oddorder
distortion cancelling is rather like like
wishing santa make a special trip in July.

Just remember that a +1V applied at the cathode gives +20V at the anode;
the tube becomes a non-inverting amplifier.

One way is to fire it up and start fiddling with bias currents,
but without tempting smoke, and see what your THD meter tells you.

If I attempted direct drive of ESL panels I'd use a far simpler
amp circuit without any SS within, except perhaps for a CCS load in an
input LTP stage.

Good Luck,

Patrick Turner.


Patrick Turner wrote in news:4608C3FE.2DCAD8A1
@turneraudio.com.au:



Prune wrote:

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven operation
anywhere. Help would be greatly appreciated!



The grounded grid curves are the same as for grounded cathode in either
pentode, UL or triode.

Voltage gains are indentical.

All that changes is the input impedance which is high for grounded
cathode, and very low for
grounded grid, and Rk in = RL / voltage gain.

There are no separtae groups of curves for grounded grid.

Musicman guitar amps used transistors to drive the cathodes of output
tubes,
and this could have been a reason why they went out of business.

Patrick Turner.

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Default Need EL34 grounded-grid curves

"Bret Ludwig" wrote in message
ups.com

You are going to have to build a test fixture and plot
them.


Nonsense. Allison is right - the existing curves apply, you just have to
apply them to a grounded grid circuit.




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Default Need EL34 grounded-grid curves

I did the XY thing with the scope, feeding a triangular wave from my
soundcard into the amp. I reduced voltage and bias current about 7%
each, and the display remains a straight line, I can't see any
curvature, unless I push it close to clipping. I don't know to what
extent it's the feedback correcting this, since the amp doesn't work
with feedback disconnected, the DC offset gets huge (even though it's
pretty low feedback since it goes back to the JFET sources, not gates).
I also can't hear any difference. So I guess I didn't have anything to
worry about...

As for the circuit being PP, I don't see it. Each side drives a
separate electrode on the headphones, but each electrode is driven SE.
A differential output amplifier is not the same as PP since the side
pushing is on the other side of the load from the one pulling at that
time.

The one problem I still have is some drift of the DC offset as the amp
warms up, so I'm hoping that several DC volts offset wouldn't be a
problem since the load is a capacitor and shouldn't draw DC.


Patrick Turner wrote in
:



Prune wrote:

Thanks, I guess that answers that question. Now if I could only find
curves for the MOSFET. The datasheet only has current vs voltage
ones.


But what current and what voltage at what electrodes?

Mosfet data should appear like pentode data, ie with Id plotted on a
vertical
scale and Ed horizontally, and the curves you see are Rd curves at
various values
of Egate.

But you have a PP circuit, and wishing for complementary oddorder
distortion cancelling is rather like like
wishing santa make a special trip in July.

Just remember that a +1V applied at the cathode gives +20V at the
anode; the tube becomes a non-inverting amplifier.

One way is to fire it up and start fiddling with bias currents,
but without tempting smoke, and see what your THD meter tells you.

If I attempted direct drive of ESL panels I'd use a far simpler
amp circuit without any SS within, except perhaps for a CCS load in an
input LTP stage.

Good Luck,

Patrick Turner.


Patrick Turner wrote in
news:4608C3FE.2DCAD8A1 @turneraudio.com.au:



Prune wrote:

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven
operation anywhere. Help would be greatly appreciated!


The grounded grid curves are the same as for grounded cathode in
either pentode, UL or triode.

Voltage gains are indentical.

All that changes is the input impedance which is high for grounded
cathode, and very low for
grounded grid, and Rk in = RL / voltage gain.

There are no separtae groups of curves for grounded grid.

Musicman guitar amps used transistors to drive the cathodes of
output tubes,
and this could have been a reason why they went out of business.

Patrick Turner.


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Default Need EL34 grounded-grid curves


"Prune"

As for the circuit being PP, I don't see it. Each side drives a
separate electrode on the headphones, but each electrode is driven SE.



** The HP operates differentially, so reducing or eliminating even order
harmonics generated in the two, anti-phase amplification stages.


A differential output amplifier is not the same as PP since the side
pushing is on the other side of the load from the one pulling at that
time.



** A simpler definition of PP is hard to imagine.



....... Phil







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Default Need EL34 grounded-grid curves


"Bret Ludwig Criminal Psychotic Septic Asshole "


Musicman guitar amps used transistors to drive the cathodes of output
tubes,
and this could have been a reason why they went out of business.



Tom Walker, I believe, did that



** Needs to be taken out and shot.

Just like the Ludpig public menace.


and I'm quite sure the basic design
worked extremely well.



** ROTFL !!

The asinine Ludwig cretin has not even the tiniest clue what the real facts
of the matter are.

Nor does he give a **** about that.

Cos he can bull**** the hind legs of a dead donkey.



........ Phil




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Phil Allison Phil Allison is offline
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Default Bret Ludpig Criminal Psychotic Septic Asshole

"Bret Ludwig Criminal Psychotic Septic Asshole "



Musicman guitar amps used transistors to drive the cathodes of output
tubes, and this could have been a reason why they went out of business.

Tom Walker, I believe, did that

** Needs to be taken out and shot.

Just like the Ludpig public menace.


and I'm quite sure the basic design
worked extremely well.

** ROTFL !!

The asinine Ludwig cretin has not even the tiniest clue what the real
facts
of the matter are.



I fixed hundreds of guitar amps. Few Music Mans because they rarely
went wrong.



** ROTFLMAO !!!!!

- so the tubes in a Music Man do not ever wear out or fail ?

- so that horribly designed, POS transistor drive circuit never blew itself
and the all the OP tubes ?


YOU clearly have ZERO experience with Music Man amps.


YOU are a KNOW NOTHING CRIMINAL LIAR !!


Bret Ludpig = Another Criminal Psychotic Septic ASSHOLE


**** OFF !!



........ Phil




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Default Need EL34 grounded-grid curves



Prune wrote:

I did the XY thing with the scope, feeding a triangular wave from my
soundcard into the amp. I reduced voltage and bias current about 7%
each, and the display remains a straight line, I can't see any
curvature, unless I push it close to clipping. I don't know to what
extent it's the feedback correcting this, since the amp doesn't work
with feedback disconnected, the DC offset gets huge (even though it's
pretty low feedback since it goes back to the JFET sources, not gates).
I also can't hear any difference. So I guess I didn't have anything to
worry about...



There are 2 x EL34 and 28 SS devices in that circuit of yours.
Worked out how each and everyone of them work?

There is also a lot of NFB in action, and slight changes of bias may not
make a visible
difference to X-Y lines on a CRO.

Harmonic Distortion measurements with something capable of measuring
down to 0.005% might tell you more.



As for the circuit being PP, I don't see it. Each side drives a
separate electrode on the headphones, but each electrode is driven SE.
A differential output amplifier is not the same as PP since the side
pushing is on the other side of the load from the one pulling at that
time.


All differential amps are PP amps, because one side turns on while the
other side turns off,
and the even number harmonic currents cancel at the cathodes, emitters,
or sources which are commoned
together to allow their combined current flow in one R or a CCS.
This occurs regardless of whether
there is a balanced input, or only one side is driven, and there does
not need to be a
mutually coupled load from anode, collector or drain as you have with an
OPT
for the circuit to be a PP circuit.
Each 1/2 of any differential circuit is an SE device, but the whole
circuit is PP,
and with all the tell tale signs of reduced 2H,4H etc.


The one problem I still have is some drift of the DC offset as the amp
warms up, so I'm hoping that several DC volts offset wouldn't be a
problem since the load is a capacitor and shouldn't draw DC.



The load is indeed a capacitor and dc drift won't worry the signal,
but you may find dc drift occurs during low level op and high level op,
and you have to analyse why this occurs if it does.

ESL usually only have a significantly pure C load which dominates the
loading at HF above 7kHz
because a treble panel is typically only 200pF measured stator to
stator.
Bass panels usually have a series resistance to feed them lest treble
production become too high.
Bass panels are typically 400 to 1,000 pF.
Some ESL have midrange panels also with series R so high pure C loads
are never seen by the amplifier
which thinks the load at 100Hz is purely resistive, and a high
resistance,
and without the shunting effect of an inductive primary
of a step up tranny. EL34 in pentode mode will have gain approaching
pentode µ at high RL values,
and so the NFB is at a maximum at LF, and declines as F rises and Z
falls for the ESL.

You need to know exactly what the L, C and R equivalent circuit is for
your arrangement
before you can say you understand your loadings.

If you were to understand the working, you could work out
at what dc anode current and at what ac signal level where there was
distortion
caused by cap charge and discharge.
200pF at 20kHz is 39k ohms and would seem to me to be an easy load
for a pair of class A1 EL34 with even a fairly low bias current.
As the C load is increased, the C load current increases.

The beauty of direct drive to ESL is that you avoid the usual step up
transformer self capacitance
which is more than the treble panel for many designs.
But otherwise, there are few if any technical benefits, so sonic
benefits are minimal.

A step up tranny may have a 1:100 ratio, so ZR = 10,000, so 200pF
connected at its output secondary without any series R becomes 2uF at
the input.
If the self C of the tranny is 200pF, you will have 4 uF at the primary,
and some amps will not cope well.

Patrick Turner.









Patrick Turner wrote in
:



Prune wrote:

Thanks, I guess that answers that question. Now if I could only find
curves for the MOSFET. The datasheet only has current vs voltage
ones.


But what current and what voltage at what electrodes?

Mosfet data should appear like pentode data, ie with Id plotted on a
vertical
scale and Ed horizontally, and the curves you see are Rd curves at
various values
of Egate.

But you have a PP circuit, and wishing for complementary oddorder
distortion cancelling is rather like like
wishing santa make a special trip in July.

Just remember that a +1V applied at the cathode gives +20V at the
anode; the tube becomes a non-inverting amplifier.

One way is to fire it up and start fiddling with bias currents,
but without tempting smoke, and see what your THD meter tells you.

If I attempted direct drive of ESL panels I'd use a far simpler
amp circuit without any SS within, except perhaps for a CCS load in an
input LTP stage.

Good Luck,

Patrick Turner.


Patrick Turner wrote in
news:4608C3FE.2DCAD8A1 @turneraudio.com.au:



Prune wrote:

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven
operation anywhere. Help would be greatly appreciated!


The grounded grid curves are the same as for grounded cathode in
either pentode, UL or triode.

Voltage gains are indentical.

All that changes is the input impedance which is high for grounded
cathode, and very low for
grounded grid, and Rk in = RL / voltage gain.

There are no separtae groups of curves for grounded grid.

Musicman guitar amps used transistors to drive the cathodes of
output tubes,
and this could have been a reason why they went out of business.

Patrick Turner.



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Default Need EL34 grounded-grid curves

Patrick Turner wrote in
:

There are 2 x EL34 and 28 SS devices in that circuit of yours.
Worked out how each and everyone of them work?


A bunch of these solid state devices are constant current sources/sinks,
and the Vbe multiplier in the second stage. There are only four SS per
side that do gain on the signal: the differential input pair, the
common-base voltage shifters (to allow DC coupling), the main voltage
gain common source stage, and the cathode drivers.

There is also a lot of NFB in action, and slight changes of bias may

not
make a visible
difference to X-Y lines on a CRO.


I'm sure it has an effect. But the NFB is not that much, unless you're
counting degenerative feedback such as the source resistors on the input
pair. The global feedback cuts gain only in half. Notice that the
feedback goes to the sources, not gates, of the input LTP. The designer
told me he did this because the otherwise needed megaohm resistors have
too much parasitic reactance. Actually I'm not sure how the resistors
are calculated. I know I have more gain than needed even now, as my DAC
puts out enough voltage swing to clip this amp. So given the spare
gain, I'm not sure if it's better to increase the global NFB or any of
the three local degenerative feedbacks instead.

All differential amps are PP amps, because one side turns on while the
other side turns off,


_Neither side turns off in this amp_. Each side swings about 750 V
peak-peak here, for a total differential of 1500 V, and both sides are
always conducting.

and the even number harmonic currents cancel at the cathodes,
emitters,


Yes, I understand that. I guess I was under the impression that PP
referred to when the load is _not_ between the two sides as is here. I
got that impression from the usual SS PP output stages where the two
sides are connected and drive one side of the load, with the other
grounded, whereas in this case the harmonic cancellation happens not at
the source/emitter connection as in the SS amp, but in the load itself.

Actually some of the cancellation is through the feedback going to the
other side as well (throught the LTP's source connection). It makes
distortion from one side appear common mode on the other side and
cancels out in the load. Even if I lower supply voltage on one side so
it clips, the other side stretches up the peak so the differential
output remains a sine. I only tried this in SPICE as I don't have a
good way to try it in the amp because I use one supply for each side.

The load is indeed a capacitor and dc drift won't worry the signal,
but you may find dc drift occurs during low level op and high level
op, and you have to analyse why this occurs if it does.


I assume by op you mean operating point?

ESL usually only have a significantly pure C load which dominates the
loading at HF above 7kHz
because a treble panel is typically only 200pF measured stator to
stator.


Well I'm driving headphones, and the Stax Omega 2 (to which I'll upgrade
in a few months) response is supposed to be from 6 Hz to 41 kHz. Stax
only provides a single number, not a graph w.r.t. frequency. I'm not
sure how I can measure it, as my LCR meter uses a fixed measuring
frequency. The datasheet says 170 Kohm at 10 kHz, so assuming no
resistance, that's 93.6 pF.

If you were to understand the working, you could work out
at what dc anode current and at what ac signal level where there was
distortion
caused by cap charge and discharge.
200pF at 20kHz is 39k ohms and would seem to me to be an easy load
for a pair of class A1 EL34 with even a fairly low bias current.
As the C load is increased, the C load current increases.


So assuming the headphone worst case is not much below the datasheet's
single given number, I shouldn't have any problem with cutting from the
original 25 to 20 mA per side. The headphones are drawing a tiny amount
of that current; it really was chosen for a specific nonlinearity and
the guy obviously had no concern with efficiency, or he woudln't have
used speaker tubes for headphones.

If I were to try to scale this up for ESL, then speaker current would be
significant w.r.t. bias, so then it would make more sense to measure the
specific impedance vs frequency for the speaker.
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Default Need EL34 grounded-grid curves



Prune wrote:

Patrick Turner wrote in
:

There are 2 x EL34 and 28 SS devices in that circuit of yours.
Worked out how each and everyone of them work?


A bunch of these solid state devices are constant current sources/sinks,
and the Vbe multiplier in the second stage. There are only four SS per
side that do gain on the signal: the differential input pair, the
common-base voltage shifters (to allow DC coupling), the main voltage
gain common source stage, and the cathode drivers.


OK, but you are still concerned about THD...

There is also a lot of NFB in action, and slight changes of bias may

not
make a visible
difference to X-Y lines on a CRO.


I'm sure it has an effect. But the NFB is not that much, unless you're
counting degenerative feedback such as the source resistors on the input
pair. The global feedback cuts gain only in half.


It looked like there was a lot more NFB

Notice that the
feedback goes to the sources, not gates, of the input LTP. The designer
told me he did this because the otherwise needed megaohm resistors have
too much parasitic reactance. Actually I'm not sure how the resistors
are calculated.


The GFB resistors of 200k each load the EL34, but lightly,
and won't have parasitic reactance over the band.
I don't think megohm R would either BTW.

If you write out all the instaneous ac Vrms at each point around the
circuit at the onset of clipping
with its phase indicated, you'll get a better idea of the circuit
working.


I know I have more gain than needed even now, as my DAC
puts out enough voltage swing to clip this amp. So given the spare
gain, I'm not sure if it's better to increase the global NFB or any of
the three local degenerative feedbacks instead.


Without building what to me looks like a complex monstrosity,
I cannot advise of best ways for fine tuning.

All differential amps are PP amps, because one side turns on while the
other side turns off,


_Neither side turns off in this amp_. Each side swings about 750 V
peak-peak here, for a total differential of 1500 V, and both sides are
always conducting.


Its still PP, even though each side remains in class A and nothing
switches.


and the even number harmonic currents cancel at the cathodes,
emitters,


Yes, I understand that. I guess I was under the impression that PP
referred to when the load is _not_ between the two sides as is here.




In class A PP, the load is considered between the two balanced outputs.


I
got that impression from the usual SS PP output stages where the two
sides are connected and drive one side of the load, with the other
grounded, whereas in this case the harmonic cancellation happens not at
the source/emitter connection as in the SS amp, but in the load itself.



PP SS class B design isn't class A operation, and is like two SE
amps working in turn for +ve and -ve halves of the signal.
The totem pole SS output stage isn't balanced most of the time.
but when biased for class A it is.




Actually some of the cancellation is through the feedback going to the
other side as well (throught the LTP's source connection). It makes
distortion from one side appear common mode on the other side and
cancels out in the load. Even if I lower supply voltage on one side so
it clips, the other side stretches up the peak so the differential
output remains a sine. I only tried this in SPICE as I don't have a
good way to try it in the amp because I use one supply for each side.

The load is indeed a capacitor and dc drift won't worry the signal,
but you may find dc drift occurs during low level op and high level
op, and you have to analyse why this occurs if it does.


I assume by op you mean operating point?

No, just low level operation, high level operation.

ESL usually only have a significantly pure C load which dominates the
loading at HF above 7kHz
because a treble panel is typically only 200pF measured stator to
stator.


Well I'm driving headphones, and the Stax Omega 2 (to which I'll upgrade
in a few months) response is supposed to be from 6 Hz to 41 kHz. Stax
only provides a single number, not a graph w.r.t. frequency. I'm not
sure how I can measure it, as my LCR meter uses a fixed measuring
frequency. The datasheet says 170 Kohm at 10 kHz, so assuming no
resistance, that's 93.6 pF.


Headphones are an easier load than a full range ESL.
C is smaller, output needed is low, so drive voltages are low.

If you were to understand the working, you could work out
at what dc anode current and at what ac signal level where there was
distortion
caused by cap charge and discharge.
200pF at 20kHz is 39k ohms and would seem to me to be an easy load
for a pair of class A1 EL34 with even a fairly low bias current.
As the C load is increased, the C load current increases.


So assuming the headphone worst case is not much below the datasheet's
single given number, I shouldn't have any problem with cutting from the
original 25 to 20 mA per side. The headphones are drawing a tiny amount
of that current; it really was chosen for a specific nonlinearity and
the guy obviously had no concern with efficiency, or he woudln't have
used speaker tubes for headphones.


I would think 25mA would be plenty.


If I were to try to scale this up for ESL, then speaker current would be
significant w.r.t. bias, so then it would make more sense to measure the
specific impedance vs frequency for the speaker.


There wouldn't be enough voltage drive for bass with ESL.
Maybe you'd need 845 tubes....


Patrick Turner.
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Phil Allison Phil Allison is offline
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Default Bret Ludpig Criminal Psychotic Septic Asshole

"Bret Ludwig Criminal Psychotic Septic Asshole "



Musicman guitar amps used transistors to drive the cathodes of output
tubes, and this could have been a reason why they went out of
business.


Tom Walker, I believe, did that


** Needs to be taken out and shot.


Just like the Ludpig public menace.


and I'm quite sure the basic design
worked extremely well.


** ROTFL !!


The asinine Ludwig cretin has not even the tiniest clue what the real
facts of the matter are.


I fixed hundreds of guitar amps. Few Music Mans because they rarely
went wrong.


** ROTULA !!!!!

- so the tubes in a Music Man do not ever wear out or fail ?

- so that horribly designed, POS transistor drive circuit never blew
itself
and the all the OP tubes ?

YOU clearly have ZERO experience with Music Man amps.


The ones I've seen failed the drive transistor and the tubes survived
fine.



** Then YOU clearly have ** ZERO ** experience with Music Man amps.

YOU know NOTING about the absurd SS drive board that was introduced and
even recommended as a retrofit.

TOTAL LUNACY !!!

The asinine Ludwig cretin has not even the tiniest clue what the real facts
of the matter are. Nor does he give a **** about that.

Cos he can bull**** the hind legs of a dead donkey.


BTW

Tom Walker worked as a ****ing ** sales rep ** for Fender.

What a joke.




........ Phil





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Phil Allison Phil Allison is offline
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Default Bret Ludpig Criminal Psychotic Septic Asshole


"Phil Allison"


Tom Walker, I believe, did that

** Needs to be taken out and shot.



YOU clearly have ZERO experience with Music Man amps.

YOU are a KNOW NOTHING CRIMINAL LIAR !!

Ludpig = Another Criminal Psychotic Septic ASSHOLE


**** OFF !!




........ Phil








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Phil Allison Phil Allison is offline
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Default Bret Ludpig = Criminal Psychpopath


"Bret Ludwig Criminal Psychotic Septic Asshole "


The ones I've seen failed the drive transistor and the tubes survived
fine.



YOU clearly have ZERO experience with Music Man amps.

YOU are a KNOW NOTHING CRIMINAL LIAR !!

Bret Ludpig = Another Criminal Psychotic Septic ASSHOLE

The asinine Ludwig cretin has not even the tiniest clue what the real facts
of the matter are.

Nor does he give a **** about that.

Cos he can bull**** the hind legs of a dead donkey.

Just like the oxygen thieving **** is trying to do right now.


**** OFF **** !!





........ Phil







  #21   Report Post  
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Phil Allison Phil Allison is offline
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Default Bert LUDPIG = a LIAR


"Phil Allison"


Tom Walker, I believe, did that

** Needs to be taken out and shot.



YOU clearly have ZERO experience with Music Man amps.

YOU are a KNOW NOTHING CRIMINAL LIAR !!

Ludpig = Another Criminal Psychotic Septic ASSHOLE


**** OFF !!




........ Phil









  #22   Report Post  
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Phil Allison Phil Allison is offline
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Posts: 1,444
Default LUDPIG = LIAR



"Bret Ludwig Criminal Psychotic Septic Asshole "


The ones I've seen failed the drive transistor and the tubes survived
fine.



YOU clearly have ZERO experience with Music Man amps.

YOU are a KNOW NOTHING CRIMINAL LIAR !!

Bret Ludpig = Another Criminal Psychotic Septic ASSHOLE

The asinine Ludwig cretin has not even the tiniest clue what the real facts
of the matter are.

Nor does he give a **** about that.

Cos he can bull**** the hind legs of a dead donkey.

Just like the oxygen thieving **** is trying to do right now.


**** OFF YANK PIG !!




........ Phil






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Patrick Turner Patrick Turner is offline
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Default ALLISON=COUNTESS


Really Bret,

Your last post does have a certain ring of mysogyny about it.

C#$T is a wonderful furry critter worth visiting with the dip stick
from time to time unless attatched to an expensive and or neurotic
sheila.

Calling Allison equal to something basically desirable is counter
productive.
Doing so with such vibrant repetivness makes you sound like a chook....

And BTW, Allison is right about MusicMan amps, when they blow, they
really blow, and make a mess of things.

After struggling to fix a couple, I saw that the Musicman could have
been better
designed if you really insist on having have a grounded grid output
stage.

Frankly, why anyone would ever bother using squalid state to drive the
cathodes
of a pair of output tubes with grounded grids is a mystery. Its a real
bull**** idea.

Guitar amps should be kept as simple as possible.

The best one I heard was a home built one by a guy who is a physics
professor
at the ANU and he used 2 x 6V6 outputs with 75% UL connections by
mistake
because he didn't understand the significance of the UL tap position
of things from his junk box, then he'd figured that another 6V6 in
triode
with an IST would make a nice driver/phase inverter, and he was right.
He didn't get much power but the sound was warm and wet, ( OK Bret,
****y ),
and magnificent.

I also like ACVox30.......

Musicman is just another amp...

Patrick Turner.

















Bret Ludwig wrote:

On Mar 29, 6:46 pm, "Phil Allison" wrote:
"Bret Ludwig Criminal Psychotic Septic Asshole "

The ones I've seen failed the drive transistor and the tubes survived
fine.


YOU clearly have ZERO experience with Music Man amps.

YOU are a KNOW NOTHING CRIMINAL LIAR !!

Bret Ludpig = Another Criminal Psychotic Septic ASSHOLE

The asinine Ludwig cretin has not even the tiniest clue what the real facts
of the matter are.

Nor does he give a **** about that.

Cos he can bull**** the hind legs of a dead donkey.

Just like the oxygen thieving **** is trying to do right now.

**** OFF YANK PIG !!


**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** ******** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
******** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** **** **** **** **** **** **** **** **** ****
**** **** **** **** **** ****

I mean, how many other ways can i say it?

  #24   Report Post  
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Phil Allison Phil Allison is offline
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"Patrick Turner"


And BTW, Allison is right about MusicMan amps, when they blow, they
really blow, and make a mess of things.


Frankly, why anyone would ever bother using squalid state to drive the
cathodes
of a pair of output tubes with grounded grids is a mystery. Its a real
bull**** idea.



** It was apparently designed by a sales rep called Tom Walker.




....... Phil



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