yes, I fully agree with it.
I am trying to debug the distortion heard. The circuit seems not to produce any clipping. I took RIAA out and checked circuit with square wave.
There is no over/under-shoot.
Triangular wave shows proper sharp edges.
So I moved on and checked if there is a problem with the preamplifier although in SE mode with the CD it doesn't do it, I am making sure that in Balance both halves are working fine.
I also noticed that there is a strange wave form on the bench if I connect phono and line and it seems to be ground related, not sure though.
yes correct.
with a cartridge though you have a floating GND.
Ground reference is generated at the circuit with shunted load.
Am I wrong?
One more comment: Optimizing the values on the RIAA i.e. doubling caps and halving resistors (roughly) and lowering degeneration resistors at the input stage, significantly reduced noise level of this circuit which now is getting magnificently low.
It probably needs a little more tweaking around and then I will repost the updated circuit.
It probably needs a little more tweaking around and then I will repost the updated circuit.
yes, but that is not what I was saying.
I was sayiong that signal coming from the Cartridge when used in balance mode only has two wires one goes to + side and the other to - side, which leaves a floating balance signal.
GND is generated at the board inside the circuit and referenced to the GND at the ouput so basically who is offering the stable audio GND is the next stage which is the preamplifier and not the input stage.
Am I saying something wrong?
Since Paradise is certainly a reference noise wise, here is the comparison of paradise vs. masterpiece.
Noise floow of MasterPiece is pretty good. I wish it could be improved further though.
Anyhow during listening the noise contribute is pretty low and you can hear all sorts of subtle details.
Anyway for the kick below is the simulation report.
Noise floow of MasterPiece is pretty good. I wish it could be improved further though.
Anyhow during listening the noise contribute is pretty low and you can hear all sorts of subtle details.
Anyway for the kick below is the simulation report.
Attachments
A balanced stage always has a 3dB noise disadvantage.
The only way to lower the noise is more paralleling of input devices.
You already lowered the emitter resistors, good for less noise but also more distortion because of lower local current feedback. That is the reason we use quite a few input devices in parallel in the Paradise with quite high degeneration.
The " compound " is then low noise plus low distortion. this is one of the reasons i am not strictly against paralleling. Theoretically it makes sense. How it sounds ?
That is at least in part subjective.
The only way to lower the noise is more paralleling of input devices.
You already lowered the emitter resistors, good for less noise but also more distortion because of lower local current feedback. That is the reason we use quite a few input devices in parallel in the Paradise with quite high degeneration.
The " compound " is then low noise plus low distortion. this is one of the reasons i am not strictly against paralleling. Theoretically it makes sense. How it sounds ?
That is at least in part subjective.
what you are saying makes total sense.
Higher degeneration a little higher noise but lower distortion and better DC performance.
Paralleling devices in my listening expeerience didn't yeald to a good result but I am willing to re-evaluate that and re-try.
Anyway, if simulator hasn't smoked anything and if this results are REAL, this is a whooppie low noise result.
If this simulation is accurate this would be the quitest phono stage in the entire history of phonos !!!!
I rearranged the RIAA and below is noise performance and re-arranged RIAA.
What do you think?
Higher degeneration a little higher noise but lower distortion and better DC performance.
Paralleling devices in my listening expeerience didn't yeald to a good result but I am willing to re-evaluate that and re-try.
Anyway, if simulator hasn't smoked anything and if this results are REAL, this is a whooppie low noise result.
If this simulation is accurate this would be the quitest phono stage in the entire history of phonos !!!!
I rearranged the RIAA and below is noise performance and re-arranged RIAA.
What do you think?
Attachments
yep and I can confirm you that the bass response is as clen as it gets.
Almost remind you of a CD player in a good sense.
Something I have never had with other phonos I have built and tried so far.
And if you think that it was better in bass area, just look at the new graph
and last...this is Christmas....free million dollar gift to everybody!!! 
My personal Masterpiece for you, standard values, absolute precision, epic bass response and ultra low noise.
Re-arranged RIAA with relative frequenqy response.
This is now, in theory so far, a breakthrough design didn't take a squat team nor 3 years like paradise to come alive ahahahahahah!!! Hopefully bench results will confirm these fantastic data.
My personal Masterpiece for you, standard values, absolute precision, epic bass response and ultra low noise.
Re-arranged RIAA with relative frequenqy response.
This is now, in theory so far, a breakthrough design didn't take a squat team nor 3 years like paradise to come alive ahahahahahah!!! Hopefully bench results will confirm these fantastic data.
Attachments
and this is a big one!!!! ahahahaha
For one thing the resistors on the RIAA have lowered which took big part of the noise down.
Plus splitting the cap apparantly took another big chunk of the noise out (no explanation for this).
Anyhow, I have ordered V-Caps CuTFT just a little bit ago and this weekend I will be conducting tests on the latest topology.
This might be the end of it in terms of phono design.
One gain, fully balance, high precision, low noise, low distortion and most of all amazing sound.
Just aside, I don't believe in miracle at all, so to me it seems almost impossible, but I am giving it a try anyway!!
For one thing the resistors on the RIAA have lowered which took big part of the noise down.
Plus splitting the cap apparantly took another big chunk of the noise out (no explanation for this).
Anyhow, I have ordered V-Caps CuTFT just a little bit ago and this weekend I will be conducting tests on the latest topology.
This might be the end of it in terms of phono design.
One gain, fully balance, high precision, low noise, low distortion and most of all amazing sound.
Just aside, I don't believe in miracle at all, so to me it seems almost impossible, but I am giving it a try anyway!!
Does reducing the riaa resistors and upping the caps also cause a higher amplification factor in this design ?
Can some of the findings here be tranposed to the original paradise ?
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