How much power can I get from 400V B+?
My OT is rated at 35 watts.
So I am just wondering what tubes I can use to achieve about 25-30 watts of audio power, other than cathode biased 4xEL84?
1. Cathode biased 4 x 6V6 ?
2. Cathode Biased 2 x 6L6 ?
Just wondering. All specs for the 6V6 and 6L6 show wattage ratings with B+ of 360V and 450V, but nothing in between, and not always with cathode bias.
Thank you!
My OT is rated at 35 watts.
So I am just wondering what tubes I can use to achieve about 25-30 watts of audio power, other than cathode biased 4xEL84?
1. Cathode biased 4 x 6V6 ?
2. Cathode Biased 2 x 6L6 ?
Just wondering. All specs for the 6V6 and 6L6 show wattage ratings with B+ of 360V and 450V, but nothing in between, and not always with cathode bias.
Thank you!
I built a fixed bias 6L6 http://www.diyaudio.com/forums/tubes-valves/133034-6l6gc-ab2-amp-50.html 400 volts B+ with MOSFET source followers and DC coupled two stage diff amp driver.
PP pairs of 6L6GC's (5881) with fixed bias will get you there.
PP pairs of EL34's (6CA7) with fixed bias will get you there.
PP pairs of KT88's with fixed bias will get you there but that's more tube than you have output transformers to handle.
You'll also need a power transformer that can source that much power.
Sheldon
PP pairs of EL34's (6CA7) with fixed bias will get you there.
PP pairs of KT88's with fixed bias will get you there but that's more tube than you have output transformers to handle.
You'll also need a power transformer that can source that much power.
Sheldon
Lots!
Is this for geeetar or hifi?
Where is your 400V coming from and how many mA can it deliver? What heater current can it deliver?
OK - what is its primary and secondary impedance?
aaaaaaahhhh you get to enter the magic realm of load lines.....
Easy entry level learning stuff here
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The poster says 4000cct, which I assume is 4K plate to plate, but who knows.
Using KT88's with 400V B+ & fixed bias with 4KA-A should get around 40W walkover and a very long life. Perhaps a luxury overkill.
The 6L6 was the standard workhorse for the popular 30W-1960's guitar amps. The number of circuits around is vast.
I often run output trannies well-over their ratings. Sofar without failure. A 100W from a 50W tranny is fine solong deep bass isn't required. The trick is not to disconnect the output under load.
richy
The 6L6 was the standard workhorse for the popular 30W-1960's guitar amps. The number of circuits around is vast.
I often run output trannies well-over their ratings. Sofar without failure. A 100W from a 50W tranny is fine solong deep bass isn't required. The trick is not to disconnect the output under load.
richy
With a PP-pair of 6L6, 807, 6P3S-E etc. you can get some 25 to 35 W depending on bias system. With fixed bias you will get more power with better efficiency.
Here is one of my amplifiers I built few years ago with Edcor transformer and 6P3S-E tubes.
It has the preamplifier, tone controls and balance, but can be easily simplified.
Here is one of my amplifiers I built few years ago with Edcor transformer and 6P3S-E tubes.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
It has the preamplifier, tone controls and balance, but can be easily simplified.
Your power transformer at 150mA ain't gonna get you there. A single 6L6GC at 400v push pull AB1 will eat up all your available current. See NJ7P Tube Database Search
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