Rather than typing the component values into LTspice in ohm, farad, etc. I strongly suggest using prefixes. Just beware that any spice simulation is ignorant of common conventions and doesn't distinguish between lower and upper case letters for prefixes. Hence m or M is milli (m) = 1E-3 and Meg is used for M = 1E6.
It's a lot easier to read the schematic and avoid mistakes when a capacitance is listed as 220n rather than 0.00000022 (I hope I got the number of zeros right).
~Tom
It's a lot easier to read the schematic and avoid mistakes when a capacitance is listed as 220n rather than 0.00000022 (I hope I got the number of zeros right).
~Tom
Which is why, after only 50 years or so of drawing schematics with a pencil or pen I settled on using the explicit form. It's actually easier, when working with a simulation, to delete or add a zero than it is to move a k.
20.76mA~
Run the transient simulation, hover the cursor (current clamp icon) over the voltage source, look in the bottom left-hand corner of the window - (minus)10.3806mA (per channel).
To see the tube dissipation, run the DC operating point simulation (right click schematic, 'Edit Simulation Cmd./DC op pnt', click OK, right click schematic, 'Run'), close the OP window, hover the cursor (pointing hand icon) over the tube, read the dissipation in the lower left-hand corner of the window.
Run the transient simulation, hover the cursor (current clamp icon) over the voltage source, look in the bottom left-hand corner of the window - (minus)10.3806mA (per channel).
To see the tube dissipation, run the DC operating point simulation (right click schematic, 'Edit Simulation Cmd./DC op pnt', click OK, right click schematic, 'Run'), close the OP window, hover the cursor (pointing hand icon) over the tube, read the dissipation in the lower left-hand corner of the window.
I am reading through this trying to understand sizing the output capacitor. I understand how 11.3 Hz is calculated thought I don't know what an ideal Hz is, but if I use my phones at 18 ohm i calculate I need an 800 uf cap on the output. If I am changing the output cap, should I be concerned about changing the 0.47 uf cap also? If changing the 800 uf cap makes sense, I would like to just add two 400 uf caps in parallel instead of getting one large cap. The math shows it is the same capacitance, but I don't know if it really has a sonic effect. The same question if I keep the 470 uf cap, sub two 235 uf caps.
I am pretty new to this as you can tell. I wouldn't think I would need to change the 1000 and 2200 uf caps because they look like they are just filtering to ground, but I am not really sure. A good resource to get a quick understand of tube circuits would be great too.
Thanks, I am very new to this. I have already build a hybrid amp and wanted to see how different a tube amp is.
Hi,
There's no need to change the 0.47mf cap of the White cathode follower neither is there any need to change the value of the cathode resistor bypass caps. You could bypass the latter with some decent film caps though.
As for resources to learn about valve electronics, there's plenty of material in the stickies at the top of the tube section here.
Cheers,
There's no need to change the 0.47mf cap of the White cathode follower neither is there any need to change the value of the cathode resistor bypass caps. You could bypass the latter with some decent film caps though.
As for resources to learn about valve electronics, there's plenty of material in the stickies at the top of the tube section here.
Cheers,
Yes it makes sense to use parallel caps if you can't find the correct value in a single cap.
A 470uF cap will work OK with 18-ohm phones, but you can add more capacitance if you like, to push the bass response down further. Why not start with 470uF, then try adding another 470uF in parallel, to see if you can tell the difference? I would be surprised if you can find a 470uF 250V film capacitor though.
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