• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Triode/Pentode Loadline Calculator

Hi Gsmok,
Can you please raise Ua max for 6S33S(one cathode) from 360 to 460. I am trying to move the operating point for my specific needs and the only limitation is Ua max.
I appreciate so much your great work with this simulator.
One thing that I noticed is the very high h3 which I hope it is not true in reality...��
Thank you again.
Best regards,
Radu
 
I would prefer to see a pentode load-line simulator, though. Is that planned for some future moment?

The load-line is an important detail, but you still have to take the other tubes that participate in creating the end result into consideration:
- Even harmonics cancellation with the preceding stages;
- Eventual feedback loops and their effects.

In my opinion, simulation of entire circuits is still the best way to go, and what we need are tools to create better Spice models.

Yes. I am preparing simulator for pentodes. I agree that simulation of entire circuits is the best tool. There are some of them on the market, and the Loadline Simulator is not in any way a competitive tool. It is a simple supporting tool based on "ancient" graphics design of tube circuits. I plan to add the function of generationg Spice models on the basis od tube data. In fact, the simulator already generates Spice models, but models are hidden.

Feature request: save a .png with the loadlines and all the data
Mayby in the future. At present there are many more useful function have to be improved.

... can i request for ecc40, great tube and should be there as well.
best regards.
k.

I added this tube.

Can you please raise Ua max for 6S33S(one cathode) from 360 to 460. I am trying to move the operating point for my specific needs and the only limitation is Ua max.
I appreciate so much your great work with this simulator.
One thing that I noticed is the very high h3 which I hope it is not true in reality..

I increased tha Uamax for 6S33S and 6S33S (one cathode).
I find it hard to relate to showed values of distortion. The calculation algorithm is the same for all tubes. Maybe it's because of inaccurate model of the tube.

BTW: I wonder if it is not worth for each tube to seperate model for this, which includes a zero voltage grid, and one that covers only the negative grid voltages. Probably, the models without zero-grid voltages will be more accurare.
 
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Hi Gsmok,
Thank you for such a fast response. Just got few pairs of 6C33c-B Svatlana today and can't wait to built with them. I heard many people saying that one cathode sounds slightly better than full throttle, and in addition have the advantage of a longer tube life...or I hope so.
Cheers
Radu
 
Can I request a model for triode-connected EL34 and/or 6CA7?

The EL34 in triode mode has been added. Check please whether simulated anode characteristics are accurate enough for you.

...Can you do the 6gk5?

I'll add it soon. If I forget, let me know again.

...Just got few pairs of 6C33c-B Svatlana today and can't wait to built with them. I heard many people saying that one cathode sounds slightly better than full throttle, and in addition have the advantage of a longer tube life...or I hope so.

I hope so too :).
I made a couple of amps on 6S33S, but always with both cathodes active. I made even one for fun on the plywood (6S33S SE Amplifier on Plywood). I also use the 6S41S tubes, which are like half of the 6S33S.
If you have a 6S33S with Swietlana logo you are a happy man :). This is rare tube. Over 90% of the tubes have a company logo Ulyanovsk, or (tubes from the 90s) does not have it at all. I keep my thumb for your design :).
 
gsmok,
Very nice amp on plywood...
I always start project on plywood. It is fast and can change things fast.
Did you do listening tests. I could not find any comments about the sound.
The reason I am tempted to start a design using 6c33 is that my previous creations are very low power ( “Shiny Eyes” PSE Special Edition | simplepleasuretubeamps), and I would like to be able to play my speakers (92dB) with more power. I am also not willing to build amps with very high voltage ( such as in transmitting tube amps).
But anyway this is out of topic.
I enjoy using your simulator. Thank you.
Cheers,
Radu
 
Did you do listening tests. I could not find any comments about the sound.

I tested it with my friends and responses were very positive for one set of output transformers (CC type core), and rather negative for the second type of transformers (EI core).


gsmok
can i request these tubes
5965 / E180CC
6BK7 / 6BQ7

OK. I added them to the requested tubes list.
 
The same malfunction I have told you before still exists.
H2 does not change when current or voltage cursor is moved, but when I slightly move yellow or white cursors, (and even return them to previous position) then H2, H4 and Htot are recalculated.

This is before I moved yellow cursor:

An externally hosted image should be here but it was not working when we last tested it.


This is after I moved the yellow cursor and then returned it to previous position.
You can see that all operating parameters are unchanged, but H2, H4 and Htot are essentially changed.

An externally hosted image should be here but it was not working when we last tested it.
 
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The same malfunction I have told you before still exists.
H2 does not change when current or voltage cursor is moved, but when I slightly move yellow or white cursors, (and even return them to previous position) then H2, H4 and Htot are recalculated.

Thank you for the examples. I thought that the mentioned bug was removed :eek:. I'll check the code again using atteched screenshots. Thanks again.

Can 6V6GT-triode and EL84-triode be added to the list?
Thanks.
Yes, of course.
 
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It's me again.
I have a problem with that error. There is no way I can get the effect of variable values ​​Htot with the same V/A parameters. Each time I select these parameters I get a result consistent with that shown in the second figure (Htot = 0.244).
When I change the voltage and/or current, value of Htot also varies smoothly.
I checked the behavior of the script undef Firefox and Windows7.

Can I ask for verifying this particular example by other users?
 
Originally Posted by artosalo

The same malfunction I have told you before still exists.
H2 does not change when current or voltage cursor is moved, but when I slightly move yellow or white cursors, (and even return them to previous position) then H2, H4 and Htot are recalculated.

I get that same error. Windows 7 Professional 32-bit on an Athlon II X3 (desktop).

The H3 and H4 readouts auto-update as I move the voltage or current arrows, while the H2 readout remains the same.

I have to wiggle the white arrow to get the program to recalculate the H2 readout.

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