Hi.
I am building an amplifier with WE 350 Beam Tetrode.
I have a dude.
In the datasheet , i can see , 16W output power with 18% of distortion , and 11 W output power with 10% of distortion. I think tetrode mode.
Can anyone imagine how many watts of that 16W or 11W could be used for audio.
In ultralinear mode could you lower the distortion ?
Santiago
I am building an amplifier with WE 350 Beam Tetrode.
I have a dude.
In the datasheet , i can see , 16W output power with 18% of distortion , and 11 W output power with 10% of distortion. I think tetrode mode.
Can anyone imagine how many watts of that 16W or 11W could be used for audio.
In ultralinear mode could you lower the distortion ?
Santiago
Attachments
Yes, 300V/80mA into a 3.3K UL transformer with 43% screen taps could give you 9W under perfect conditions.
I would run at a little less voltage and a little less current and accept 7-8. You will still need to deal with THD/damping issues.
I would run at a little less voltage and a little less current and accept 7-8. You will still need to deal with THD/damping issues.
300V 80mA is near to maximun , but Western Electric tubes are strong.
I suppose.
With a KT88 UL could obtain the same 8W or 10W?
Santiago.
A KT88 in 43% UL with 300V P-K and 100mA of quiescent current into a 3K load looks pretty potent, as in maybe 18W. Having messed with single ended KT88s, I wouldn't expect that much in practice.
Is a lot for one SE tube.
Maybe will be a good option. ( Better than WE 350B ? )
15w seduce me.
Do you have any proven diagram ?
Nope. If you wanted to be absolutely assured of 15+W, then pentode operation may be more reasonable.
I can take a stab at one. Do you have any parts you're wanting to use specifically?
I can take a stab at one. Do you have any parts you're wanting to use specifically?
audiowize,
I am ideally looking for a SE Ultralinear.
With 450v max, and I'm seeing which tube could give me more watts.
EL37,6550,KT66,KT88 etc. I have 803 and 813 tubes , but i dont know if are a good option with 450V.
You could get ~30W with an 813 run as a pentode on 450V. The 803 would do about the same. Both would require A2 operation.
The 6550/KT88 is somewhat easier. The RH88 would apparently make about 12W with UL loading, and it runs on the B+ you're interested in
The 6550/KT88 is somewhat easier. The RH88 would apparently make about 12W with UL loading, and it runs on the B+ you're interested in
Attachments
Of course, but i do not understund the 100v in the grid with the anode. in the graphic of right.
I think the diagram is suggesting a zener diode between plate and screen (represented by a battery showing a fixed voltage difference).
No, it suggests running G2 a hundred volts HIGHER (more positive) than plate. (Note G1 voltage for each condition.) That will increase peak "available" cathode current (which is limited by load impedance). For any reasonable *audio* use, it will abuse the screen grid. On original 6L6 we would expect quick failure. (6L6GC is tougher.)
I do not understand the doubts. 350 is a 27 Watt Pdiss tube. A good pentode in SE can make "undistorted" output about 0.4 times Pdiss. Or 10 Watts. At high THD and high impedance (poor damping). You can reduce THD and impedance with NFB. Ultralinear is one way. But that's not much NFB. The classic design is a high gain stage before the power stage and NFB overall.
I do not understand the doubts. 350 is a 27 Watt Pdiss tube. A good pentode in SE can make "undistorted" output about 0.4 times Pdiss. Or 10 Watts. At high THD and high impedance (poor damping). You can reduce THD and impedance with NFB. Ultralinear is one way. But that's not much NFB. The classic design is a high gain stage before the power stage and NFB overall.