Also the constant current pull of the DCB1 PSU does not allow any time break to the transformer.
I have a case where in DAC output I have 10Vrms to drive unity gain Nelson Pass F4 amplifier. Is it possible then to increase the voltage on DCB1 from -/+10V to -/+15V? Is it actually necessary to increase the voltage to buffer 10Vrms signal?
Yes you can increase to +/-15V rails, and you must because 10VRMS makes 28.3V peak to peak swing.
Hi. I have 6pcs of unknown R core transformers which write pt011a on them weight about 1kg and I think they are 60va. I measured them and they have about 22v CT AC on secondaries. When I connect 39r2 50w voltage drops to 42.15v from 44.74v. Can I use them as hot rod but for biamping. I want to use 4 channel. Should I connect 10R 10w non inductive resistors in series maybe it will help? And what mods should I do on standart board? Many thanks
22V-0-22V output transformers, correct?
That's unfortunately too high for DCB1. Wants 15V-0-15V at most.
Dropping with series resistors isn't as nice as having the right transformers since the resistors will dissipate heat and add impedance.
On the other hand because the DCB1 power section draws constant current its easy to predict the right secondary dropping resistors value and their power spec. PSUD2 should be very helpful to picture the situation.
AC-0-AC is the power input format of DCB1 stereo boards so you will need two CT transformers and two boards to have four channels.
That's unfortunately too high for DCB1. Wants 15V-0-15V at most.
Dropping with series resistors isn't as nice as having the right transformers since the resistors will dissipate heat and add impedance.
On the other hand because the DCB1 power section draws constant current its easy to predict the right secondary dropping resistors value and their power spec. PSUD2 should be very helpful to picture the situation.
AC-0-AC is the power input format of DCB1 stereo boards so you will need two CT transformers and two boards to have four channels.
Yes they are about 22v ct transformers. Sorry i do not have extra budget and want to use these transformers.I saw somebody uses 2x18v ac as transformers so i thought maybe i can also use my transformers by adding resistors in series . Is not 60va R core transformer enough to power 2 boards? 2 transformers may be better though.
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Using same windings for 2 different rectifier causes gnd loop maybe? So maybe 2 transformers and hot rod mode may be logical. 600ma and 10R resistors maybe solves the problem then.Resistors are already 10w. These transformers are ultra silent. I want to use them a lot.
I also need about 5x gain with opa627 opamps and want to make active crossover too. Do you think there will be a problem to put all in one enclosure? And do you have a good idea how to implement it?
Which order do you recommend? Gain - crossover and b1 buffer? Or vice versa. What will be the effects? İmho b1 at the end may sound warmer. But I am open to better opinions if possible.( My dac is muse dac6x ) I also have better days but they need to be fixed. I am not looking for high volumes
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Salas what happens if one puts a resistor in primary to reduce the secondary when there is higher voltage transformer than required, though resistor be larger to dissipate the heat but are there any sonic differences?
Because its constant current drawn by DCB1's shunt PSU section I don't predict a flaw since CCS is high impedance isolating what's before it. At least for critical audio band frequencies. If it was just a typical PSU it would have a modulation impact because of worsened transformer regulation. That is why in heavy power amplifiers having soft start systems with power resistors in the primary they switch them out with a relay after a little time when reservoir capacitors have charged.