Building a symmetrical PSU B1 buffer

diyAudio Chief Moderator
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Where, in the regs? That has to do with how I wanted the closed loop gain graph of the dc error amp and what kind of phase margin I got, then with subjective evaluation on the point to point proto. There is no rule of thumb 'small' or 'big' for those.
 
Hi William,
What is the colour LED that you are using ?
I understand that the Lightspeed is sensitive to ambient light . Do you find this a problem with the LEd next to the silonix ?
regards
kp93300
Why are you assuming that? The Silonex devices are potted and isolated from the exterior ambient light. Though I don't know what tolerance it has. I mean, in extreme light conditions it may be affected. But not at all in a closed enclosure.

I don't know if a shunt regulated for the LDRs will give any improvement. After all, it is driving a led. Could be a good experiment to hook up a regulator and checking with a scope if the resistor varies with ripple or whatever
 
Just to say that finally it's up and running!:cool:

In the 'wild' but it's working!

The 10 Ohm resistors are temporary while Mills arrives...

Also the pot (a lightspeed will mount there) and the 100 uF caps are temporary, I'll mount sockets to swap different caps.

In the attached photo is near the 'wild' MyRef. :D
 

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Yesterday i hotrodded my dcb1...i added a 5w 10ohm resistor to the 1w 68r resistors...giving me when measured 7.9ohm
2.04v/7.9 = 258ma
1.73v/7.9 = 218ma

Wow what an improvement!!! The soundstage has opened up wider and deeper, i am hearing sounds all around me(yes sounds even coming from behind me!!!). As a result i can tell where singers or instruments are very easily, and can even differentiate between backing singers. Now this is what i call Holographic. Detail has also gone up a notch and sounds more dynamic, yet the music never grates, i just want to keep on listening....BUT...

After listening for about 30mins (Yes i could tell all the above with just 30mins of listening!) i checked to see the temperature on the mosfets, by touching them with my finger, OUCH way too hot cant touch it very long before it burns, so i took out some heatsinks from an old computer powersupply that doesnt work and listen again for about 30mins, this time the temperature of the mosfets are cooler then before but still too hot, and there is no way im going back to 60ma after hearing it at circa 200ma!!! So i take out the 12v fan from the computer power supply and connect it to an unused 12v tap on the small toroid. After another 30mins of listening i checked the temperature of the mosfets and they are cool :up:

Next up i will install the fan into the cover of the chassis, and i will try the salas shunt reg to run the Optivol

Special thanks to Salas, Nelson Pass and all who participated to make the DCB1 possible :worship:
 

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Hi Andrew, yes i do remember at the time thinking, that they sounded better when the fan was on them, but if it really was better, it would of been a very minimal improvement, maybe cleaner sounding, but not as big an improvement as going from 60ma to 240ma. I should also state that before i went up to 240ma i went to 80ma and did notice an improvement, but again it was slight, but it did improve with the soundstage increasing in depth and width and sounds seeming to float in the room, again more of a 3d sound just not to the extent of going up to 240ma.

Alon
 
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Those Mosfets still amaze me with their ruggedness. So tiny sinks and they survived. Didn't I tell to use proper sinks or bolt to thick floor so many times? You can't run on same sinks you use for regular setting a hot rod. OK, killing a Mosfet is no big deal, but if someone uses a DC amp without output relay DC sense, bye bye speakers. OTOH, when prepared rightly the anti environmental setting attitude has some subjective benefits.:D