Revisiting some "old" ideas from 1970's - IPS, OPS

Looks excellent!

I think, we will add one more resistor placeholder in series with both both R6 and R15 - the optimal value would be some 5.8...5.9 Kohm - easier to add-up by 2 resistors.
It's pretty well-balanced by itself - only 56mV at the servo output, easy job for the servo.
I think, it's going to become our "flagship" IPS board for Modular series.

Is the front-end running cooler in terms of temperature, just by touching the local heatsinks?
Do you mean that i must place two 5k6 resistors in series for eatch R6&R15?
Please post a draft schematic.:)
I will make temperature measurements soon.
 
Do you mean that i must place two 5k6 resistors in series for eatch R6&R15?
Please post a draft schematic.:)
I will make temperature measurements soon.

That's what I mean (red arrows) ;)
 

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vz-x4 analyzed using RightMark Audio Analyzer.
 

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These look good! I don't see as much 50 or 100HZ noise on these ones. Did you try something new with your test equipment?
Good catch!
This problem solved in this way.
Resistor divider in a metal box fitted direct in sound card input.
Still some noise components above 1KHz... however - better than before.
Yes but these are present in the source signal too.(right channel);)
My choice:
WinAudioMls: Audio Realtime Analyzer for Windows platform using FFT and MLS

Yes i like your choice but i haven't the money:(
SpectraLab.
 

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Another factor is the quality of the PC's PS. A great reduction of higher
order noise when I moved up to a Seasonic/Corsair supply versus those OEM/
cheap Asian supplies.

I notice this with either onboard or top of the line (ASUS Xonar).
It does not take much when you are dealing with >-100db signals.
Audio quality in general also increases with the better PC supply.

PS- ground straps between removable motherboard trays - PS - main
case are another improvement that can be added.
My PC is my main audio/HT device !

OS
 
Last edited:
Another factor is the quality of the PC's PS. A great reduction of higher
order noise when I moved up to a Seasonic/Corsair supply versus those OEM/
cheap Asian supplies.

I notice this with either onboard or top of the line (ASUS Xonar).
It does not take much when you are dealing with >-100db signals.
Audio quality in general also increases with the better PC supply.

PS- ground straps between removable motherboard trays - PS - main
case are another improvement that can be added.
My PC is my main audio/HT device !

OS
Glad to see you here Pete!
My PC power supply isn't a no name cheap one.
I has try a very expensive PC power supply in the past without any improvement.