Hi ! i see a socket on the back for a single +24VDC power supply ... do you mean that from this they make a dual supply for the circuit ? i am very interested how they have done this Do you have any idea of the actual circuit ?
By the way ... the parts used have very high specs I mean already reading the datasheets the potential can be clearly seen Of course one thing is the limit and another thing to reach it
Thanks a lot for pointing at this very interesting piece of electronics.
By the way ... the parts used have very high specs I mean already reading the datasheets the potential can be clearly seen Of course one thing is the limit and another thing to reach it
Thanks a lot for pointing at this very interesting piece of electronics.
Not sure what's on the back of the pcb, but here you have all the possibilities explored:
Virtual Ground Circuits
I used two of them in my last project having a headphone amp with equaliser in the feedback path.
One of those circuits is an ac-dc active-passive splitting ground for the headphone's amp circuits , another one is just an ac splitting ground to provide the headphone's ground.
That's kind of redundancy as the ac-dc virtual ground circuit can do it all, but it's not really .I didn't want to provide any dc current to the headphones themselves more than the leakage current of the output capacitors . not even a tiny bit.
The only real difficult choice i had to make was if i choose to have a high speed composite op-amps with no output capacitance or a simple passive circuit.I chose to have three active LH0002 buffers in parallel, out of the feedback path of the op amp driving them setting the dc level in paralel with a passive RC ground generator.
LH0002 can provide a fairly low output impedance outside a fdeedback loop if driven by the op-amp's low impedance and thus i could add a lot of output capacitance not needing a fast op-amp.It was just a curiosity if the circuit would work properly.I didn't fire it yet...
Maybe i could have used the lme49600-lm49710 application with a half supply zenner as i have some of them
DON'T ASK phono and headphones amplifier with equalization
Virtual Ground Circuits
I used two of them in my last project having a headphone amp with equaliser in the feedback path.
One of those circuits is an ac-dc active-passive splitting ground for the headphone's amp circuits , another one is just an ac splitting ground to provide the headphone's ground.
That's kind of redundancy as the ac-dc virtual ground circuit can do it all, but it's not really .I didn't want to provide any dc current to the headphones themselves more than the leakage current of the output capacitors . not even a tiny bit.
The only real difficult choice i had to make was if i choose to have a high speed composite op-amps with no output capacitance or a simple passive circuit.I chose to have three active LH0002 buffers in parallel, out of the feedback path of the op amp driving them setting the dc level in paralel with a passive RC ground generator.
LH0002 can provide a fairly low output impedance outside a fdeedback loop if driven by the op-amp's low impedance and thus i could add a lot of output capacitance not needing a fast op-amp.It was just a curiosity if the circuit would work properly.I didn't fire it yet...
Maybe i could have used the lme49600-lm49710 application with a half supply zenner as i have some of them
DON'T ASK phono and headphones amplifier with equalization
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