Since you can custom order its better with 17VAC secondaries because it will save you some heat on the DCSTB's sinks without any sound quality loss. Useful move at 150mA bias level especially.
Rather 20k with few exceptions due to differentiated system synergy. The lower the pot's value the faster rise time and wider bandwidth in this preamp thus a "tighter" sound you get. Also read post #79 "few words about power" on what are the current demands and minimal suggestions on how much CC limit to set when not using the DCSTB PSU but SSLV1.1 or 1.3 current limiter equipped shunt regulators.
Salas,
Thanks. That’s perfect because my 20k smd fleabay stereo attenuator sounds great and are only 12 bucks. Vendor is lasercollection
Read 79: 33 peak to peak with my loudspeaker will be way beyond what I need
I’ve got R1 on both + and - BiBs at 3R. So I will be good.
Cheers,
Greg
Says (79) more CC for common between channels shunt reg. You got 200mA CC per rail now with 3R when two DCG3 channels pull 200mA bias per rail (low bias mode). Use 2R R1 CC setting resistors for 300mA CC in your 1.3. And that's conservative, good enough for line level use and high impedance headphones.
RS02B2R000FE70 Vishay / Dale | Mouser
RS02B2R000FE70 Vishay / Dale | Mouser
Yeah, misread that. I was thinking 100ma per pole was plenty with a 100 ma buffer. Will do.
You can keep your 24VAC secondaries transformer from your BA-3 because you got a very big sink for the shunt regs as I have seen in your photos in other threads. UltraBiB's M1 MOSFETS (when R1=2Ω) are going to dissipate 4.5W each and M2s 1.73W each with that trafo and +/- 17.3V DC output setting for the DCG3 at 100mA bias mode.
Those are mins for any headphone use also, in dual mono shunt PSU configuration. He will be using it for line level in common shunt PSU configuration between channels.
You may go to 300mA pos CC & 200mA neg CC with dual mono shunts and 18VAC secondaries in your config. The chassis base should still suffice.
You may go to 300mA pos CC & 200mA neg CC with dual mono shunts and 18VAC secondaries in your config. The chassis base should still suffice.
Your UltraBiB PSU has a CCS current limiter so it will protect the load (DCG3) from a fault higher to your R1 mA setting anyway. If surpassed it will drop the PSU's output voltage and you will instantly know by the PSU's LEDs turning off. Not only useful in test, but forever, its a built in feature. I put the CCS there primarily for dynamic separation reasons but it works as a CC protection mode too.
The dim bulb tester will sense the 6800uF reservoir capacitor's inrush current and try limit it but once charged it will not react for brightness any further. Because the PSU's current draw will be maintained constant no matter what gross fault may occur after its current limiter. Naturally it won't protect what's located before it i.e. the transformer, the bridge diodes, and the reservoir capacitor.