OK. Thanks LC.
BTW smps is great improvement over analog ps. A totally different amp. !!!
I told you guys long time ago, I perform a lot of tests so you don't have to worry about anything.
I'm glad that you hear the same difference over conventional PSU. Toroids and big elco banks are a history for me.
I always say it sounds different never say improved or better
At certain point one comes to a conclusion that better is the right word.
I recommend to try it some day.
I'm a beta tester of a new SMPS brand .I test the F1 with it but also these modules from Thel Audio Audiophiler Hochstrom-Spannungsregler, einstellbar, Voltage Regulator
Hi back
TR1 and TR2 sets DC offset plus VAS bias current at the same time. Both works in pairs reciprocally as explained in User manual instructions - last chapter. +/- 5 mV of output DC offset is easy to set with TR1 and TR2, which is quite remarkable result as we speak of no DC servo control here. VAS bias current is 12 mA at cold start, also set with TR1 and TR2.
TR3 sets the output bias current which for the whole amp (complete amp's idle current - no signal connected) has to be 280 mA.
Hopefully you'll find the way to persuade the amp to work as intended.
Please be very careful, measuring probes sometimes likes to jump between pads making short circuits with catastrophical results.
Regards, L.C.
TR1 and TR2 sets DC offset plus VAS bias current at the same time. Both works in pairs reciprocally as explained in User manual instructions - last chapter. +/- 5 mV of output DC offset is easy to set with TR1 and TR2, which is quite remarkable result as we speak of no DC servo control here. VAS bias current is 12 mA at cold start, also set with TR1 and TR2.
TR3 sets the output bias current which for the whole amp (complete amp's idle current - no signal connected) has to be 280 mA.
Hopefully you'll find the way to persuade the amp to work as intended.
Please be very careful, measuring probes sometimes likes to jump between pads making short circuits with catastrophical results.
Regards, L.C.
Hi Back, if it's same procedure as on VSSA it's a balance and need concentration. Both TR1/TR2 increase VAS bias in clockwise direction, and decrease Vas bias anti clockwise, as qouted LC you shall end up at 12mA when cold. Which one (TR1/TR2) needed to be turned depend on DC offset, if DC offset is too positive the one pull offset in negative voltage, and if DC offset is too negative the other pulls offset in positive direction. Using two DMM is best, this way you have reading of VAS bias and DC offset in realtime. You need all time to read and strategic pick the correct trimmer to end up 12mA and no DC offset.
Here is visual helper from VSSA thread though VAS bias had another target: http://www.diyaudio.com/forums/vend...lateral-mosfet-amplifier-321.html#post3814157.
Here is visual helper from VSSA thread though VAS bias had another target: http://www.diyaudio.com/forums/vend...lateral-mosfet-amplifier-321.html#post3814157.
If mounted to proper heatsink 1 minute is an appropriate time to set DC offset and VAS bias at cold start. Later, when heated DC offset should be rechecked and corrected but only with one trimmer (TR1 or TR2), not affecting VAS bias.