However if you use a 300ppm VR instead of Vref device then expect anything to happen to output voltage.I compared a trimmer vs a low ppm Vref resistor.
How do you say "Balderdash !!"
Understand how the regulator works and give it a chance to work properly.
The idea of using a VR as the sole device in the Vref string is defeating the whole SALAS reg philosophy.
AndrewT I don't want to discuss with you I know we hear AC but don't forget all is DC powered.
I understand also semis have tempco & surely affects more to the reg.
I know Salas philosophy and I know LEDs are less noisy than resistors.
Still don't answered how do you say: "Balderdash"
I understand also semis have tempco & surely affects more to the reg.
I know Salas philosophy and I know LEDs are less noisy than resistors.
Still don't answered how do you say: "Balderdash"
AndrewT I don't want to discuss with you I know we hear AC but don't forget all is DC powered.
I understand also semis have tempco & surely affects more to the reg.
I know Salas philosophy and I know LEDs are less noisy than resistors.
Still don't answered how do you say: "Balderdash"
"Balderdash" is just a colorful way of saying "Poppycock" , at least as far as low tempco resistors goes according to his analysis.
You aren't alone: welcome to the "Golden Ears Club"
well I have an AXON 4,7 uF PP at output and clearly see his dark signature
that Is why ask
for me AXON Is not a option at all
"Balderdash" is just a colorful way of saying "Poppycock" , at least as far as low tempco resistors goes according to his analysis.
Thanks
Balderdash is a concise but polite and slightly old-fashioned way of saying "I´m sorry but my experience prevents me from agreeing with that. = pamplinas (con cariño).
I think balderdash = tonterias
where's my voltage gone
Hello,
I'm building a two box Pearl II RIAA setup with SSLV1.1's. Tx, rectification bridges and first caps (4700uF) are in the PSU box. 0V lines are tied together when entering 3 wire umbilical. Shunts with additional 4700uF caps and RIAA boards are placed in the other.
At the entering of RIAA box I've got nice and steady 35.3VDC. Meanwhile after connecting SSLV with dummy load (600R) attached, I've got 30.5VDC on board smoothing cap and can't get my target 24V right.
I used two red leds, 1.8 kOhm for R303 and 5K trimmer for my Vref setting. With the trimmer at the max there's above 22Vout.
What might cause the lowdown? I've tried PSUD2 simulations and none of them confirm the actual voltage behaviour.
Thanks.
Hello,
I'm building a two box Pearl II RIAA setup with SSLV1.1's. Tx, rectification bridges and first caps (4700uF) are in the PSU box. 0V lines are tied together when entering 3 wire umbilical. Shunts with additional 4700uF caps and RIAA boards are placed in the other.
At the entering of RIAA box I've got nice and steady 35.3VDC. Meanwhile after connecting SSLV with dummy load (600R) attached, I've got 30.5VDC on board smoothing cap and can't get my target 24V right.
I used two red leds, 1.8 kOhm for R303 and 5K trimmer for my Vref setting. With the trimmer at the max there's above 22Vout.
What might cause the lowdown? I've tried PSUD2 simulations and none of them confirm the actual voltage behaviour.
Thanks.
Normally the 35.3 to 30.5 should be bcs you CCS load your Tx and rectification stage.
Lets assume a 3mA (in circuit Id) mid way GR K117 in your Vref and 6.8K max resistance. That gives 6800*0.003=20.4V plus Vbe and Led(s). Looks normal. Boost your Vref. How high you wanna go? No more than 24-25Vo with your Vi I would suggest. Try 3K3 instead of 1K8 and see what happens.
Lets assume a 3mA (in circuit Id) mid way GR K117 in your Vref and 6.8K max resistance. That gives 6800*0.003=20.4V plus Vbe and Led(s). Looks normal. Boost your Vref. How high you wanna go? No more than 24-25Vo with your Vi I would suggest. Try 3K3 instead of 1K8 and see what happens.
Question about SSLV 1.1 BiB and BHL Audio JFET phono preamp kit
I want to be use the BiB for a BHL Audio JFET phono preamp kit for my MM Phono System.
The phono preamp needs a current draw less than 50 mA by 24V. I want to be using a talema 2x12 416mA (1x24V) as transformer.
What is the recomandation for c101,102,103,104.
C101 220uF,C103 47uF Elkos or
C102,C104 Wima MKS 4,7uF(or10uF) + R1 1R?.
Thanks for your help
greetz kokonut
I want to be use the BiB for a BHL Audio JFET phono preamp kit for my MM Phono System.
The phono preamp needs a current draw less than 50 mA by 24V. I want to be using a talema 2x12 416mA (1x24V) as transformer.
What is the recomandation for c101,102,103,104.
C101 220uF,C103 47uF Elkos or
C102,C104 Wima MKS 4,7uF(or10uF) + R1 1R?.
Thanks for your help
greetz kokonut
I want to be use the BiB for a BHL Audio JFET phono preamp kit for my MM Phono System.
The phono preamp needs a current draw less than 50 mA by 24V. I want to be using a talema 2x12 416mA (1x24V) as transformer.
What is the recomandation for c101,102,103,104.
C101 220uF,C103 47uF Elkos or
C102,C104 Wima MKS 4,7uF(or10uF) + R1 1R?.
Thanks for your help
greetz kokonut
Tx 1x24 is OK near 10V difference to target Vout to avoid mains fluctuation.
Prefer C302 MKT except for very sensitive digital like clocks or MC phono, if you have 10uF better than 4.7uF so C101 don't solder nothing.
For C304 also film cap better 10uF than 4.7uF so if you use film C303 don't solder nothing.
Hi folks,
can I use 2R2 instead of 1R for the zobel filter. Then I would be able to use my favourite brand.
Best regards, Erik.
I believe no but you can parallel two 2R2 and measure if the value is 1R
I guess that would likely be closer to 1R1 and a simple DMM resistance measurement would, incorrectly, show 1R3-1R5I believe no but you can parallel two 2R2 and measure if the value is 1R
Thanks for the fast info. for c104 i have also to use the 1r resistor. yes.Tx 1x24 is OK near 10V difference to target Vout to avoid mains fluctuation.
Prefer C302 MKT except for very sensitive digital like clocks or MC phono, if you have 10uF better than 4.7uF so C101 don't solder nothing.
For C304 also film cap better 10uF than 4.7uF so if you use film C303 don't solder nothing.
what will be the best choice for R303 to reach the 24V? 220R + 10k trimmer (more general) or 1k8 + 5k trimmer ?
Thanks a lot
back on track
Changed 3K3 instead of 1.8K in Vref and now can regulate my target voltage to 24V. All seems OK. With dummy connected, I've got 31VDC before the BIB onboard cap and around 30.9VDC on it. Salas tells me 6V vin-out is enough.
I get around 135mA CCS current with 10R current setting res. That should be alright as Pearl II RIAA consumption is 60mA max.
Ready to test the negative reg.
Thanks for all your help again, Salas.
Changed 3K3 instead of 1.8K in Vref and now can regulate my target voltage to 24V. All seems OK. With dummy connected, I've got 31VDC before the BIB onboard cap and around 30.9VDC on it. Salas tells me 6V vin-out is enough.
I get around 135mA CCS current with 10R current setting res. That should be alright as Pearl II RIAA consumption is 60mA max.
Ready to test the negative reg.
Thanks for all your help again, Salas.
Thanks for the fast info. for c104 i have also to use the 1r resistor. yes.
what will be the best choice for R303 to reach the 24V? 220R + 10k trimmer (more general) or 1k8 + 5k trimmer ?
Thanks a lot
BiB guide says 10-25V 1K8 + 5K trimmer, my advice is use 1K8 + 10K trimmer and adjust Vout to 24V once adjusted take off the trimmer & measure it so you can replace the trimmer value + 1K8 = fixed low ppm resistor
Thanks for your info. i will do that this wayBiB guide says 10-25V 1K8 + 5K trimmer, my advice is use 1K8 + 10K trimmer and adjust Vout to 24V once adjusted take off the trimmer & measure it so you can replace the trimmer value + 1K8 = fixed low ppm resistor
A voltage reference will perform better than a resistor.
Usually a voltage reference will have a few ohms or maybe tens of ohms of dynamic impedance. A resistor must have a dynamic impedance equal to it's resistance. If you use a 1k0 resistor as your voltage Vref string then the dynamic impedance will be 1k0, If you use a 20V Zener & a 100ohm VR set to 49ohms then the dynamic impedance will be very approximately 60ohms. That is approximately 14 times lower impedance of the Vref. That makes for a better regulator, not 14 times better, but quite a bit better.
Instead of a Zener, you can use LEDs as Vref elements. Most of these Salas regulators use a short string of red LEDs just because they allow the regulator to perform better. 20V from a string of red LEDs would require 10 to 12 LEDs. That is a bit too many, a Zener would probably be better for this higher voltage.
No matter whether a resistor has a 5ppm or 50ppm or 0.5ppm tempco, it can never have a dynamic impedance as low as an appropriately selected Vref semiconductor.
Usually a voltage reference will have a few ohms or maybe tens of ohms of dynamic impedance. A resistor must have a dynamic impedance equal to it's resistance. If you use a 1k0 resistor as your voltage Vref string then the dynamic impedance will be 1k0, If you use a 20V Zener & a 100ohm VR set to 49ohms then the dynamic impedance will be very approximately 60ohms. That is approximately 14 times lower impedance of the Vref. That makes for a better regulator, not 14 times better, but quite a bit better.
Instead of a Zener, you can use LEDs as Vref elements. Most of these Salas regulators use a short string of red LEDs just because they allow the regulator to perform better. 20V from a string of red LEDs would require 10 to 12 LEDs. That is a bit too many, a Zener would probably be better for this higher voltage.
No matter whether a resistor has a 5ppm or 50ppm or 0.5ppm tempco, it can never have a dynamic impedance as low as an appropriately selected Vref semiconductor.
Last edited:
- Home
- Amplifiers
- Power Supplies
- SSLV1.1 builds & fairy tales