I have a plan of building 2E22 SE ampli. Could anyone give me specs and plate curves of this tube in triode mode.
Thank you and regards,
Thank you and regards,
Running triode strapped, it is supposed to be like a directly heated KT88, although it is only good for 30 watts instead of 40W like the KT88.
http://frank.pocnet.net/sheets/084/k/KT88.pdf
See page 7 of the document.
http://frank.pocnet.net/sheets/084/k/KT88.pdf
See page 7 of the document.
Not like a KT88 , more like a cross between 6L6 / 6V6 . Mu 8 ra 2k . I've done a PP amp with 2E22 , sounded ok but low power
316a
Vg2 max on data is 250V. It's real barrier for high voltage in triode mode, so we cannot get high power out. But it's in penthode and in class C. It can be different in case of triode mode.
I have seen a schema in which Vak is 420V for 2E22 in triode. But that circuit works stable for more 1 year. wow🙄.
If I can get its data on triode mode, then I can choose optimal OPT , B+ voltage, also operating point.
I ran 2E22 as triodes at 350V A-K 55mA with the usual 100r g2 anode strap resistor . No issues . Optimal output transformer approx 6k SE , 8k-10K PP
316A
316A
How much is Vg in that case ?
My plan is Vak 400V, 70-75mA for G2 and anode, OPT 5K. This mode is bit like for KT88 or 300B 🙂 What do you think about it ?
some people say sound of 2E22 is somewhat like 300B 🙂
My plan is Vak 400V, 70-75mA for G2 and anode, OPT 5K. This mode is bit like for KT88 or 300B 🙂 What do you think about it ?
some people say sound of 2E22 is somewhat like 300B 🙂
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funny phrase : 2E22 is 300B for poorman.... I'm poor now 😀
2E22 can run into class A2, so I think it can get more power if the driver stage is strong enough.
I've tried many driver tubes for 2E22. E180F Philips gold pin show fantastic. This is my favorite. Sound is great, very very warm and rich tone, bass is so good. No complaint so far 🙂
AC hum is acceptable at my position.
Does 6V6 here need hang/elevation of heater ?
AC hum is acceptable at my position.
Does 6V6 here need hang/elevation of heater ?
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Yes, elevate the heater to the 6V6, you could tie the filament winding directly to the cathode, but I recommend something like a 100K resistor to filament and a 1uF from filament to ground instead to isolate the output from disturbances on the AC power.
I would move the choke ahead of the 6V6 plate and take advantage of the low output impedance the 6V6 would provide.
I would move the choke ahead of the 6V6 plate and take advantage of the low output impedance the 6V6 would provide.
How do You run 2E22 @ 370-375V G2 screen grid?
When MAX for G2 is 250V in datasheets?
When MAX for G2 is 250V in datasheets?
The answer is Triode operation.
In triode operation, screen voltage can never be higher than anode voltage.
The problem with pentode operation has always been when Ug2 > Ua, when the "current-crossover" sets in.
For example, look at the GU50 datasheet. http://www.mif.pg.gda.pl/homepages/frank/sheets/043/l/LS50.pdf
Max. screen voltage is 250V (first page). But when connected as triode, max Anode and G2 voltage can be as high as 400V. (last page)
Thus, 2E22 with 375V in triode should be fine.
NFB divider Res 245R/11R seems to be fit for this amp. Gain come lower a bit, Noise is reduced significantly so I can not hear hum noise at my chair. Bass get more control cause of better damping, high frequencies become more opened. Maybe this is my final version.
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Hi, this project looks interesting , i was thinking cathode bias 8 watts for the 2E22 in triode mode