Krill - The Next Generation

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W

wahab

Member
Joined 2009
Steve Dunlap said:
. I show a bias current 20% lower than what you reported, and 100% higher than wahab reports. He is using different software, and changed the value of 3 resistors in the schematic, .
Click to expand...

what is changed are the two 36.3R resistors that set the currents
of the two CCS, that are sat at 36R in my sims..
you will surely notice that it increase the CCS currents by slightly
less than 1% , the same figure that a 3° C increase in temperature
of the two diodes and bjts wich serve as CCs...
the other resistor is the one that set the Iq current, changed from
1.7K to 910R to set the current at a value of 105 mA per power devices..
all this doesn t change nothing to the sim s validity...
 
Steve Dunlap

Steve Dunlap

Member
Joined 2008
scott wurcer said:
...
WIRE 544 1008 544 960
FLAG 2416 384 0
FLAG 544 -272 0
FLAG 544 1008 0
FLAG 624 176 A
FLAG 464 416 0
SYMBOL npn 864 224 M90
...

...
SYMATTR Value SINE(.12375 29 {freq})
...

Circuit: * C:\Documents and Settings\swurcer\Desktop\AUDIO\krill\Krill20.asc

Direct Newton iteration for .op point succeeded.
.fourier quantity "V(c)" not pressent in data.


LT spelling not mine (this time).

:wave:
Click to expand...

Cut and past from the net list.

TEXT 256 472 Left 0 !.param num_cycles 20\n.param num_fft_pts 2048\n.param freq 20\n.param timestep {1/((num_fft_pts-1)*freq)}\n.tran 0 {num_cycles/freq} 0 {timestep}\n.options plotwinsize=0\n.four {freq} V(c)
Click to expand...

I figured out what is going on here.:troll::nownow:
 
Steve Dunlap

Steve Dunlap

Member
Joined 2008
wahab said:
what is changed are the two 36.3R resistors that set the currents
of the two CCS, that are sat at 36R in my sims..
you will surely notice that it increase the CCS currents by slightly
less than 1% , the same figure that a 3° C increase in temperature
of the two diodes and bjts wich serve as CCs...
the other resistor is the one that set the Iq current, changed from
1.7K to 910R to set the current at a value of 105 mA per power devices..
all this doesn t change nothing to the sim s validity...
Click to expand...

So you don't think cutting the bias to 1/2 the previous value will have any impact on the performance of an amp circuit? Since you insist on changing the circuit from what I posted, there is nothing left to discuss here.:wave2:
 
T

tinitus

Ex-Moderator R.I.P.
Joined 2005
My, thats impressive, very serious
Classy simulations, real artwork
If only I could design amps that way
Cant imagine all the fine amps I would build
Man, this place would be floated with master amps
Well, too late, SS amps are soon gone anyway

But if you design powerful SMPS, it might make you the most popular man around
Or maybe just give in and hang your hat on someone elses work, like many others do it

Good luck
 
W

wahab

Member
Joined 2009
well if current is set at 200 mA per device, that makes 800 mA
for the complete ouput stage...
with such currents, no amplifier output stage will switch off
completely, so you re right, no use to study the thing further,
since there s nothing left that is worth more studies...
 
T

tinitus

Ex-Moderator R.I.P.
Joined 2005
I was previously lectured that this switching off wasnt about bias

Anyway, does 800mA make a full blown classA amp
Well, I didnt know that
Is that really true
I dont know

You keep beating us with all this fancy knowledge
But as I dont understand any of it, neither do I know if I can trust you
I mean, do you know, or do you just think you know
Im not sure I can respect what you are saying
Especially in light of the way things are going here

Tho its funny that those who have actually built a Krill amp are happy and have no complains
Not one single post about any problems
And from pictures I can tell you, they were certainly not built like any classA amps
Smaller heatsinks, if you get my point
Thats what I relate to
They do the serious work, and no hiding behind computer simulations
They have my respect

Maybe you should do some serious work and build this amp
Show what its about
All this talk about small numbers is really just empty hollow talk to me
It just seems pointless, and neither is it very creative
Sorry, but thats how it looks from my side
 
W

wahab

Member
Joined 2009
Steve Dunlap said:
Here is the output stage WITH the 20 ohm resistor added. I also added the large cap across that resistor, as that was mentioned. I'm sure the value won't be what someone else would have used, but we have already established, a few posts back, that part values don't matter.

I have included a screen shot showing the output current minimum at 20 Hz at rated output power into 8 ohms. I show the value for an emitter resistor minimum. the blue trace is an NPN emitter. The green trace is for a PNP emitter. On the blue trace, the current is well above the spec sheet figure of 5uA max for cut off current. In fact, it is almost 100 times greater. The green trace has a minimum of about 1.13mA minimum.

I have also included the LTspice files so anyone can check this for themselves.
Click to expand...


all simulations are in fact useless....
we can see in the asc file posted by steve that there s a gross error..
the voltage supply source V2 has his positive side connected to the normaly negative rail of the output stage...
LTspice is really heroical..does it deal with such mistakes?..
 
T

tinitus

Ex-Moderator R.I.P.
Joined 2005
jkeny said:
Sorry, tinitus, I don't know who you're comments are directed at, Steve, wahab, - can you address them so readers can be clear?
Click to expand...

Oh, sorry

Well, afraid to say I may fear that Steve will be one of the very last SS amp designers to appear here
I think it might have been better to try and make him feel more wellcome, instead of this
He deserves great respect fore still being around

In the end, those who care about themselves only, they dont care about the rest of us
Neither do they have any intentions to help any of us in any way
Its their own right to live like that, as long as they stay to their own things
But its not ok to mess it up fore the rest of us
 
J

jkeny

Member
Joined 2007
tinitus said:
Oh, sorry

Well, afraid to say I may fear that Steve will be one of the very last SS amp designers to appear here
I think it might have been better to try and make him feel more wellcome, instead of this
He deserves great respect fore still being around
Click to expand...
I agree totally but there are some here who insist on this endless antagonistic barrage of criticism & doubting of Steve's integrity based on simulations (edit: & their infinite experience & expertise)

Listen, we all know you are smart dudes, you've proven it again & again - can you just leave this thread alone & let us poor deluded souls tease out our fantasies!
 
Last edited:
W

wahab

Member
Joined 2009
fact is that the LTspice sim file posted by steve in the post 341
has a big error...
both positive and negative rail are supplied with +34V....
thus, if one was to run the file, only the positive
side of the output stage will work..
surely a sign of great engineering capacities, according to tinitus..
 
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