Definitely offer parts and pcb, I'm possibly considering a 10W version which will require a different heatsink and chassis, so only need parts/pcb.
I think it's a bit early to say that the heatsink options we we'll have won't work. You don't know what we're offering!
You need to add the option for running a 1/2W resistor from the base ztx450 to it's emitter. Not shown on the original schematic but should be there.
C103 of 1000u might cause instability on some switch mode power supplies. To be safe I probably wouldn't exceed 100uF, Nelson used 10uF here.
Good to see Elna Silmics used.
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That's my bias mod. Which means I used what I could find, that resulted in 1.22A. Nothing to do with optimisation.
Using 2.2k gives a higher bias figure.
I'll have a look around for the 2.2k resistor and retest. I might have a chance to do it tomorrow.
Well, I guess depending on your distortion results I might go for your bias mod.
Though I'm about to change to 24v supplies so most interested in which bias reeults in lower distortion.
The 2.2k resistor will certainly be better. But maybe the improvement is only another 0.1% drop to 0.7%.
It's just about finding the right compromise in order not to overheat the parts on the existing heatsink.
I have some other parts which will bring the distortion down below 0.1% but maybe it sounds better with more distortion not less.
Fun to try though.
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As soon as they have been tested and proven, I will certainly do that.
I will aim to do that before Friday.
Found the problem. Audio Analyzer was set to FLOAT, which didn't cause issues with the Asus supply but did cause issues on the kit supply.
I will post results shortly.