The simplistic Salas low voltage shunt regulator

[Salas]

It will work, and have worked, with smaller, less capacitive Mosfets. Its elastic. I prefer the stronger Gm, less bandwidth, and reliability of the big ones though.

 

[iko]

but I think my simulations showed that is was faster.

are we still trusting simulations ?

hehe

You might just have to prototype it and let us know what happened

 

[mikelm]

that is my plan for today

 

[nicoch58]

well the amp works

Shunt after 1,5h of music,

Dx 44,82v -44.93v

SX 44.99v -45.01

T ambient 26.5°

Q6(100r) 46°

outmosfet 51°


amp with bias 675ma T sink 43°

 

[Salas]

We want photo!

 

[nicoch58]

Frankenstein look better!!!

Q6 is safe ?

 

[Salas]

Sure it is safe. Does Franky have a melodic voice at least?

 

[nicoch58]

is 10 day that I dont hear music ,first impression ,so and so ,a little delusion rispect all stuff I put in the amp....

separate trafo for driver
dual mono psu with kG Super Through
dual mono Salas shunt (to do r6 mod)
dual mono psu for pw, pana to KG gold and stealth diode,duoble the size
all psu wire supra ,and supra ply for speakers ,mundorf for internal signal
lower bias for summer 825ma to 675ma


I have lost my personal loved balance in the female voice, little dry with little more sibilance , but There is better details and clean sound ,better bass, no gain in hopes sound stage

need some burn in ,and for me... r6mod and more tantalium resistor

 

[nicoch58]

Frank

under 500w rcore and toroid-psu driver

 

[nicoch58]

 

[iko]

Monstrous heat sinks! I likey!

Edit: just got back from the Luminato festival, a week long festival of concerts and other artsy stuff in Toronto. Saw some great guitar playing today, and boy, the sound there, it kills all my audio stuff. Well, live concert beats everything, AFAIC. And tomorrow .... Sonny Landreth, a legend of slide guitar. And it's for free

 

[nicoch58]

25x30cm and is not the best !with 40v and bias 800ma ,I see 51° with T anbient 32°



live sound ,I have a Gibson with 100w tube fender and two 12", what dinamic!!!!

 

[Melon Head]

I have a Fender Jazz, with 600W Trace Elliot (hybrid amp) and 2x10 speaker cabinet.

 

[nicoch58]

Thanks a lot Salas !!

now after 10h burn in and found R L resersed all sound sweet !
the Shunt do a lot of microdetail/separation note ,es: on vinyl Lonestar Norah J the separation on mirror voice are stunning ,I can see it

and platter are more estended but sweet

I have strange more static/pop

PS offset 0,5ma

 

[nicoch58]

with a small string of copper after 4h the mpsa55 is at 51° ,ok?

 

[Salas]

With 100R under it? Those junctions can go up to 150C max. RthetaJC is 83C per W. Given the derate factor for ambient and hours of use its like using the 625mW device at 400mW under nominal ambient. Sounds pretty safe to me.

 

[nicoch58]

OK thanks ( with100r ), the other channel is at 47, need to redo my andmade heatsink


do you like Franky??

 

[Salas]

P.S. Do you have 4 pieces 2SK170GR? Or 4 pieces BL, but low Idss around 6mA?

 

[nicoch58]

only 6.28 6.17 7.30 728

I have 3.50 in the pacific riaa

 

[Salas]

If you cut the 4 1k 550/560 load resistors and join g,s on 4 2SKs, you can use them instead of those resistors. Drain on V+ for positive, drain on 560 collector for negative. You must watch the Centigrade on the BCs. I would prefer the GRs. Franky I like, and it will sound smoother and opener with that mod.