hello ,
i test the build to OTL / Class A to EL 504 ( up EL 502 or 6P45s ) .
the power in build is small
, +/- 600 mW to 8 Ohms .
i joint the schéma and pictures to build to test .
and sound for the test 2 EL 502 for 1 Way ( 1 triode ECC 83 )
Test Prototype OTL - Music Freddie Mercury - Vidéo Dailymotion
nice sound for very small build ( and big consumer energy ) ...
tk , good day for all
i test the build to OTL / Class A to EL 504 ( up EL 502 or 6P45s ) .
the power in build is small
, +/- 600 mW to 8 Ohms .i joint the schéma and pictures to build to test .
and sound for the test 2 EL 502 for 1 Way ( 1 triode ECC 83 )
Test Prototype OTL - Music Freddie Mercury - Vidéo Dailymotion
nice sound for very small build ( and big consumer energy
) ...tk , good day for all
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I think you need some form of negative bias for the grid (G1). As drawn the only bias for the tubes will be due to the 25R resistance of the choke L1.
With 170V B+ to bias the tubes at 70% dissipation, you need about -24V of bias.
Without this the tubes will run very hot (red plate) and suffer short life.
Be aware that the output on the top of the inductor can go negative if the amp is driven hard enough, resulting in reverse bias on the output capacitor(C2).
With 170V B+ to bias the tubes at 70% dissipation, you need about -24V of bias.
Without this the tubes will run very hot (red plate) and suffer short life.
Be aware that the output on the top of the inductor can go negative if the amp is driven hard enough, resulting in reverse bias on the output capacitor(C2).
Hello TheGimp ,
the L1 is up to 56 Ohms approximatly and the power is 160 V= +/- 5V=
the all's tubes ( EL 504 or EL 502 and maximum EL 509 / 6P45S ) is adjoint small résistor to equal ( +/- 1 Ohms ) to série at inductance to 56 Ohms .
the test in prototype to 2 EL 502 use 1 Hour is good , not red plate
tk for help
the L1 is up to 56 Ohms approximatly and the power is 160 V= +/- 5V=
the all's tubes ( EL 504 or EL 502 and maximum EL 509 / 6P45S ) is adjoint small résistor to equal ( +/- 1 Ohms ) to série at inductance to 56 Ohms .
the test in prototype to 2 EL 502 use 1 Hour is good , not red plate
tk for help
Det kunde man räkna från dig ....Nice! I did exactly the same thing with 4x PL504 per channel ten years ago, burned almost 300W to get 2x 0,75W out
But this kinds of experiments are refreshing, do (and het workibg) and watch other do.
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