Can I use IRFP9240 both at the output and the CCS??
If so, will R101 remains at 1.8R please ??
Electrolytes caps and polymers were done on reflektor. Poplypropylenes and evos oil on Salas SSLV on both positions.
I did also test Evos with reflektors.
So eventually I could copare reflektors evo oil and sslv evo oil runing at 7V for I/V and buffer for pcm1704.
Reflektors gave more spacious sound with bigger sound stages, while SSLV as I previously wrote was more tube like, more heavy sound. Refelektor were also shorter on bass and had thinner sound. I liked SSLV better in this position. Maybe Refelktor needs bigger capacitance for leds filetering ...
My next steps will be to power directely the dam1021 resistors ladder @ 4V, with refelktros and sslv BJT. Possibliy I will try Mcap Supreme EVO Oil, which is "induction free" design cap. Who knows maybe that matters as well
An externally hosted image should be here but it was not working when we last tested it.
Electrolytes caps and polymers were done on reflektor. Poplypropylenes and evos oil on Salas SSLV on both positions.
I did also test Evos with reflektors.
So eventually I could copare reflektors evo oil and sslv evo oil runing at 7V for I/V and buffer for pcm1704.
Reflektors gave more spacious sound with bigger sound stages, while SSLV as I previously wrote was more tube like, more heavy sound. Refelektor were also shorter on bass and had thinner sound. I liked SSLV better in this position. Maybe Refelktor needs bigger capacitance for leds filetering ...
My next steps will be to power directely the dam1021 resistors ladder @ 4V, with refelktros and sslv BJT. Possibliy I will try Mcap Supreme EVO Oil, which is "induction free" design cap. Who knows maybe that matters as well
An externally hosted image should be here but it was not working when we last tested it.
Wow! I didnt realize there could be such a difference among caps in a power supply. I thought it was mostly coupling caps that were subjectively different.
Any comments on K73-16 caps?
nash
Is there a p-channel compliment for BF256? For use in V1.2R negative regulator? I'm having trouble finding it.
very little choice for Pchannel jFETs.
Build two positive regulators and connect each to a separate secondary winding on the transformer feeding their own PSU.
If the bf256 is a G to S short making it a CCS, then you can simply turn it around when in a negative regulator.
The DCB1 has a +ve and -ve regulator pair and it uses N channel jFETs.
Build two positive regulators and connect each to a separate secondary winding on the transformer feeding their own PSU.
If the bf256 is a G to S short making it a CCS, then you can simply turn it around when in a negative regulator.
The DCB1 has a +ve and -ve regulator pair and it uses N channel jFETs.
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what output capacitor is recommended. I see some users have chosen polypropylene and some use electrolytic. Which is actually recommended and what is the least and whats the maximum value recommended?
IMG_1798_zpse988d779.jpg Photo by tonyjukes | Photobucket
in the above pics they look like WIMA lower values may be 2.2uf or so but what do you recommend salas?
IMG_1798_zpse988d779.jpg Photo by tonyjukes | Photobucket
in the above pics they look like WIMA lower values may be 2.2uf or so but what do you recommend salas?
Here you have salas response for the same question
http://www.diyaudio.com/forums/anal...otrodded-blue-dcb1-build-545.html#post4745241
That's what I'm listening to at the moment. But they are series style not shunts, and I want to listen to a shunt regulator.
Do you think a positive-negative pair would provide any sonic advantage over a pair of positive regulators?
The V1.2R regs with cascoded JFET CCS "tail" we discussed JFET equivalents for are positive and negative designs already that use NJFETs only. For MOSFETS and BJTs they use opposites. They are the first two schematics from the "revision" link in post #2 of the "The simplistic Salas low voltage shunt regulator" thread. The thread where this discussion belongs better by the way.
I have fired up my SSLV today and something is not right. I am feeding VDC directly from a another PCB.
Initialy I bridged the diode positions wrongly and applied DC with the rails shorted across. it blew the fuse and after that I soldered the DC input directly to the positions after the diodes, next to the big capacitor.
Right now I power up and the green leds light up but the red ones in the voltage reference do not. I have about 1.5V across the R101 resistor and the heatsink is getting warm. On the positive reg DC output voltage is rising very slow to about 22V and the trimpot doesn't allow any adjustment. On the negative reg VDC is rising also slow to about 30V and then lowers to about 18VDC.
Any ideas?
Here is a summary of the calculated values from the spreadsheet.
DC Feed Parameters DC In 42 Vdc
Operating Point V Out 32 V
Constant current (Q101) 250 mA
Load Consumption 50 mA I Shunt (Q106) 200 mA
D102A Vf 0 V
D102B Vf 2 V
D103 Vf 2 V
D104 Vf 2 V
R101 5,5 Ohm
Q103 Idss 3,6 mA
D101 0 V
D105 1,9 V
D106 1,9 V
R103 - 6810Ohm
R105 1023 Ohm
Initialy I bridged the diode positions wrongly and applied DC with the rails shorted across. it blew the fuse and after that I soldered the DC input directly to the positions after the diodes, next to the big capacitor.
Right now I power up and the green leds light up but the red ones in the voltage reference do not. I have about 1.5V across the R101 resistor and the heatsink is getting warm. On the positive reg DC output voltage is rising very slow to about 22V and the trimpot doesn't allow any adjustment. On the negative reg VDC is rising also slow to about 30V and then lowers to about 18VDC.
Any ideas?
Here is a summary of the calculated values from the spreadsheet.
DC Feed Parameters DC In 42 Vdc
Operating Point V Out 32 V
Constant current (Q101) 250 mA
Load Consumption 50 mA I Shunt (Q106) 200 mA
D102A Vf 0 V
D102B Vf 2 V
D103 Vf 2 V
D104 Vf 2 V
R101 5,5 Ohm
Q103 Idss 3,6 mA
D101 0 V
D105 1,9 V
D106 1,9 V
R103 - 6810Ohm
R105 1023 Ohm
Salas is it recommended to use BF256B instead of 2sk170 as original toshiba parts are hard to find and I really doubt about the LSK170 as I was not really that happy with the lsk170s which i have tested before. What do you suggest can we use BF256B?
Im currently using 10000uf Mundorf psu at the main rectifier 100uf nichicon FG at the Vref and 100uf Muse for the output to power the dac with 600ma CCS and what I found is the resolution is good but the bass firmness is missing its ok but not good. So using a film capacitor like a polypropylene 10uf > only < for the output cap will solve that problem as its esr will be very low.
Im currently using 10000uf Mundorf psu at the main rectifier 100uf nichicon FG at the Vref and 100uf Muse for the output to power the dac with 600ma CCS and what I found is the resolution is good but the bass firmness is missing its ok but not good. So using a film capacitor like a polypropylene 10uf > only < for the output cap will solve that problem as its esr will be very low.