Hi Ed,
There is also the Kuroda Amp1 of 2019 mentioned here https://www.diyaudio.com/community/...-implemented-on-blameless.356086/post-6246923 with a link that shows the following circuit
Q16,Q17 are the power diodes using power transistors. R5,R6 10 Ohms across the diodes like the E Van Drecht patent, but still not nonswitching IMO.
But notice the shunting large capacitors C1,C7 across the bias transistors -- which IMO will kill the autobias loop at HF. Otherwise it is very close to the autobias I am using -- apart from the CCS's Q11,Q14, where I use fixed resistors to floating/bootstrapped +/-9V supplies (for less dissipation in the CCS's).
It would be interesting to simulate ths amp without C1,C7 AND with R5,R6 node broken to the output, to make it NSB. Maybe with R5,R6 link broken the autobias spreaders won't need the shunting capacitors? Anyone interested in simulating these mods?
There is also the Kuroda Amp1 of 2019 mentioned here https://www.diyaudio.com/community/...-implemented-on-blameless.356086/post-6246923 with a link that shows the following circuit
Q16,Q17 are the power diodes using power transistors. R5,R6 10 Ohms across the diodes like the E Van Drecht patent, but still not nonswitching IMO.
But notice the shunting large capacitors C1,C7 across the bias transistors -- which IMO will kill the autobias loop at HF. Otherwise it is very close to the autobias I am using -- apart from the CCS's Q11,Q14, where I use fixed resistors to floating/bootstrapped +/-9V supplies (for less dissipation in the CCS's).
It would be interesting to simulate ths amp without C1,C7 AND with R5,R6 node broken to the output, to make it NSB. Maybe with R5,R6 link broken the autobias spreaders won't need the shunting capacitors? Anyone interested in simulating these mods?
Hi Ed,
Shinichi Kamijo wrote "Evolve TLB – Power amplifier with Trans-Linear Bias" https://x.com/nikstankovic_/status/1798217258885410963
His "simple TL bias" circuits look similar:
Fig 25 using bipolar's and Fig 27 using lateral's, Fig 28 test results. In Fig 27 power diodes D1,D2 are body diodes of 2SK3844 MOSFET's. Presumably the bias spreaders are thermally linked to these diodes.
A translated version of the memo is attached.
Cheers, IanH
Shinichi Kamijo wrote "Evolve TLB – Power amplifier with Trans-Linear Bias" https://x.com/nikstankovic_/status/1798217258885410963
His "simple TL bias" circuits look similar:
Fig 25 using bipolar's and Fig 27 using lateral's, Fig 28 test results. In Fig 27 power diodes D1,D2 are body diodes of 2SK3844 MOSFET's. Presumably the bias spreaders are thermally linked to these diodes.
A translated version of the memo is attached.
Cheers, IanH