2.7 and 2.6 A across R3, respectively to previous voltages.
So… 4.4 and 3.9 Watts? I need to research Ohm’s Law.
While I’m educating myself, test speakers are singing sweetly! Sounds LOVELY. And it has an absolutely pitch black background of nothingness.
After about an hour of on-time, it’s warm, but not F5 warm. Definitely under 50C on the sinks.
I’m enthralled! It’s my newest and simplest amp! Thank you all!
So… 4.4 and 3.9 Watts? I need to research Ohm’s Law.
While I’m educating myself, test speakers are singing sweetly! Sounds LOVELY. And it has an absolutely pitch black background of nothingness.
After about an hour of on-time, it’s warm, but not F5 warm. Definitely under 50C on the sinks.
I’m enthralled! It’s my newest and simplest amp! Thank you all!
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You want to measure across R3. Are thise measurements on two legs of R3 with other side of multimeter at ground? And what about R4?
If this is directly across R3 and it’s a 1 ohm then 1.62V - 1.48V = 0.14V therefore 140mA bias going through 2SK2087C
Something is odd since you also said that you’re getting 1.1Vdc across the inductor. These 159ZC are 0.7 ohm therefore the current going through them to generate 1.1Vdc would be 1.1/0.7 ~ 1.6A
For now enjoy the music but later on I’d be curious to know your bias...😀
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As I tried to describe before, my measurements were done across the two pins of R3. DVM leads only on the legs of one R3 resistor. I measured across R3 on one board, then R3 on the other board. I measured for voltage first, then current. It seems I’m in the ballpark because the amp was warm and playing music nicely. I will repeat my measurements tomorrow after the amp has warmed up again.
I think I got it, when you wrote “one side is 1.62 the other is 1.48” you meant your 2 voltages across each R3 for your 2 channels and NOT your DVM leads for 1 channel. Sorry if I misunderstood, looks like you’re all set 👍
One R3 had 1.62V going through it. The other R3 (other amplifier channel entirely) had 1.48V going through it. Two separate measurements for two different resistors.
😆 “…Third base.”
😆 “…Third base.”
It sounds FANTASTIC! Thank you for bringing the design to the forum!
My 3U300 heatsinks have 53C at the hottest part of each sink. Everything works wonderfully, so I don't think I will press my luck just yet. 🙂
I could use a little more gain with it in my system, but I expect that is just part of the source follower topology. It won't get very loud, but it has just enough grunt to satisfy my listening environment.
My 3U300 heatsinks have 53C at the hottest part of each sink. Everything works wonderfully, so I don't think I will press my luck just yet. 🙂
I could use a little more gain with it in my system, but I expect that is just part of the source follower topology. It won't get very loud, but it has just enough grunt to satisfy my listening environment.
Glad to hear you are enjoying it. Yeah, the gain is slightly less than 1, so the preamp has to provide all of it. I also think it sounds better after temps have stabilized… about an hour.