Because I am lacking the self discipline to call it a night rather then try just one more idea or respond to help provided... I am getting better though, didn't post last night's results.
I appreciate pointing out the mistake. 🙂
I can only go by the limited information and understanding I have. This is why I didn't buy a kit and build, stepping back and learning. I am almost done with the elementary electronics book, already read Morgan Jone's book on amplifiers, still have his layout book to read, though feel best after the pre amplifier book I forget the author of.
I am nut sure what you are getting at.
The schematic, BOM and more information is available and has been on my website for quite a while now.
https://www.skunkiedesigns.com/tubelab-spp-clone
If you have questions about that amp design, there is a long thread on this forum full of any information anyone would possibly need to build one, and where people way smarter than me can answer your questions. I am truly sorry for interrupting here, carry on with your journey.
https://www.skunkiedesigns.com/tubelab-spp-clone
If you have questions about that amp design, there is a long thread on this forum full of any information anyone would possibly need to build one, and where people way smarter than me can answer your questions. I am truly sorry for interrupting here, carry on with your journey.
That doesn't answer my question in the least. You have to have a reason for changing a 47k resistor to 470k. "Try just one more idea" is not sufficient. Similarly you have to have a reason for shunting an input coupling capacitor with a resistor, or shunting a grid stopper resistor with a capacitor, whichever way you want to look at it: and again, 'try just one more idea' is not sufficient. It also isn't an explanation. Try it why? What was the underlying idea?
The 470k resistor that should be a 47k resistor is shunted by 0.022uF, whose impedance < 470k above 15Hz, so the resistor can't do its job of grid stopping, because your input circuit is invalid.
I suggest you stop guessing.
Last edited:
It does, I said it was a mistake. Why else would I thank you for correcting me?
The other message is I was tired.
Sorry neither were clear.
Are you referring to the plate bypass?
Soon as had the opportunity I corrected it.
I suggest stop assuming. 😛
The values are based on the results of the filter formula and double checking the distortion.
Capacitor changed.
The results.
The voltages for the EL84. There is also an odd peak to the waveform of the tube, didn't get a chance to run though the other simulations and see if there is an answer. I ask, though that be asinine.
And the slightly modified schematic.
The results.
The voltages for the EL84. There is also an odd peak to the waveform of the tube, didn't get a chance to run though the other simulations and see if there is an answer. I ask, though that be asinine.
And the slightly modified schematic.
Did try and build a simple schematic (regenerative one tube tuner with antenna receiving signal, so be a mild challenge), however, somehow messed up the tube and also building a potentiometer. I did it to see if possible, with no instructions, to sit down and build something, turns out almost is, I think the fault is understanding files available and instead of building a component, find one until have more experience. The program is intuitive and easy to build a simple schematic.
Here are the original formulas, suspect where the fault is as all the nodes are connected in the above test circuit.
Here are the original formulas, suspect where the fault is as all the nodes are connected in the above test circuit.
The schematic I find has left and right channel inputs like an integrated. Seems then inferring the channel inputs are split.
I never have seen this on an amplifier, what advantage is there?
I didn't find your thread by viewing all threads created by you, so why responding here.
Almost certain read through one of the threads (read a number of build threads), no specifications mentioned. Thought maybe have the figure handy.
Hi Adriel,
Here is an example of a potentiometer. You already have the library file, but I forgot to include the symbol file (attached, unpack the archive and put the .asy file in lib\sym\).
Here is an example of a potentiometer. You already have the library file, but I forgot to include the symbol file (attached, unpack the archive and put the .asy file in lib\sym\).
With that change the grid is disconnected from the circuit from DC point of view. Not good, it means the voltage on the grid is unpredictable.
Now the grid is connected to ground via the grid stopped resistor R21 and the grid leak resistor R1. C11 is used just to stop possible DC voltage from the signal source (very rare these days for a standard audio line output).
There is a good writeup about grid stoppers here: https://www.aikenamps.com/index.php/grid-resistors-why-are-they-used
One peculiarity of this potentiometer is that it cannot have position 0% and 100%. You have to set either something very low like 0.00001 or something very high like 0.9999999 for the minimum and maximum position value. This is because LTSpice does not allow a resistor with zero value. Not a big deal though.
The model is not showing up, file extension is correct, so really puzzled.
Even tried re-naming and putting in both the sym and switches folder, that didn't work either.
Update. Tried installing others and the same results. Did the program get corrupted and needs to be re-installed?
Last edited:
This is why I keep posting the schematics, I am bound to make mistakes. So thank you for the assistance and education.With that change the grid is disconnected from the circuit from DC point of view. Not good, it means the voltage on the grid is unpredictable.
Now the grid is connected to ground via the grid stopped resistor R21 and the grid leak resistor R1. C11 is used just to stop possible DC voltage from the signal source (very rare these days for a standard audio line output).
Interestingly, the resistor before the capacitor gets less distortion and lower output and this arrangement (which I of course sticking with) produces almost four times as much (0.02 versus 0.07THD) with more output watts.
I appreciate this. Interestingly, found this in earlier research and why put one in.
So the voltages on the EL84 are suitable for at least normal tube life?
There is something strange. The zip archive I sent you has "pots.asy" inside, not "pots_10K.asy. Where that came from?
Please note that the value of the potentiometer is given when you use it in an schematic. The symbol itself has no value, it is a symbol for any potentiometer, not just for a 10K one.
You just need to make sure that you can see pots.sym in LTSpice\lib\sym\, like this:
You can also try restarting LTSpice. But first let's make sure the symbol file is in the right place.
Darn it. Why of late folks are unable to understand me?There is something strange. The zip archive I sent you has "pots.asy" inside, not "pots_10K.asy. Where that came from?
Please note that the value of the potentiometer is given when you use it in an schematic. The symbol itself has no value, it is a symbol for any potentiometer, not just for a 10K one.
You just need to make sure that you can see pots.sym in LTSpice\lib\sym\, like this:
You can also try restarting LTSpice. But first let's make sure the symbol file is in the right place.
As I showed in the pictures, both the original and the re-named are in the sym folder. Despite this, not showing in the components directory inside LTSpice. In other words, there is a discrepancy.
Can you show me in Windows explorer the file in the sym folder? Not from Ltspice, but from Windows.
I be more than glad to, why turn down generous and kind help?
Yesterday I also tried tossing into a sub folder just for grins, no difference.
Your idea of re-starting has worked!
Just finished breakfast, I can't eat and model, too distracting. 😛
Do you mean me? If so, not the first person to call me patient. A lot of it has to do with my logical brain, sees things needing solutions as puzzles. Take for example writing scripts for frequency to compute distortion and output, I probably could find a working text or write and run a half dozen times and maybe learn something.
Or running another model every 50Hz. I wish a way to sweep, but, good things come to those that are patient.
Well if ever have a model not working, I found there are folks here who love to and will make it work without asking.