Salas hotrodded blue DCB1 build

Have just tried the lightspeed in dcb1. Earlier in my AN linestage I tried
Alps Blue -> noble pot -> tkd cp2511 (all 100k dual logs)

The TKD was best, then noble and so alps blue.
The ldr volume control was much better than these (with regards to soundquality) but the volume tracking with the AN preamp was a bitch. Just perfect with the dcb1.
 
While the optivol is inspired by and similar to the Lightspeed, it is NOT the Lightspeed. The LSA is minimalist/passive design without buffer. The power supply is only there to supply the LEDs, which are not in the signal chain. The optivol has a buffer, so you are listening to that as well.

In my system, the (passive) LSA lacked drive and volume and the highs were missing, even with 1.5M ultra low capacitance cables. However, the LSA is so highly regarded elsewhere in DIYA that I want to stick with it. Hence, I will add the DCB1 buffer, which I am confident is better than the optivol's buffer.

There are 5 commercial variations of the second generation Lightspeed that I know of. George (inventor) will say that all 4 clones are inferior to his.
 
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sad news here

It's been a month since my dcb1 was finally housed in an appropriate box. When I passed to change the track today, I've inhaled a light warm smell of plastic coming from inside the box. After opening it, I found a tripplet of mosFET Vgs setting leds down. It's on a positive rail with a heatsink running blimey hot. Does that mean one of my Mosfets are down? Curiously, the music was still playing and the voltages measured OK.
 
Well I have a question

I have a 50va 15-0-15 rcore

Using a 10r mosfet source resistor gives 1.2 odd volts across the resistor.
This translates to 120mA,where did the rest go?

Again paralleling 2 10r gives 1 V across the resistor, so 100mA while it should have been around 300mA

There must be something wrong with my understanding
 
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The Mosfet Vgs rises with higher current setting and nears the particular Leds total. Either stronger Vf Leds or smaller setting resistors will do the setting you aim at. If you got enough Vin-Vout then all is a matter of particular semis characteristics. How high a DC you can measure across the bigger smoothing electrolytics?
 
Too much of the good thing is not good for me ;-).

500mA for me adds dollops on bottom taking chunks out of mid & top.200mA for me.

Hey its winter :)
And where in the world would you get the last real stand of the royal Bengal tiger (sunderban - 70miles)....drive on seabeach (90 miles)
Sip you favourite poison while seeing the sun setting on third highest peak of the world (300 mile)
 
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