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.
Offset d.c never was a measurement issue😉
Just all hysteresis capacitors changed to 1-2.2uf.
Yes - light trimming of LTP currents, so that the voltage drop over resistors, marked 0.5V, becomes closer to 1/2 of the voltage drop over the resistors, marked as 1V (now it's roughly 0.6V vs 1V).
If we keep this as final modification it is necessary to modify the Vbe multiplier too.
Now the end of Vbe trimmer is nothing more than 21mV over 0.44R emitter resistors.
Temperature on four transistors is 47°c when room temperature is 23°c
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Well, now the VAS output went a bit below 5mA.
We can either slightly tune-up R24 || R25 for increasing it back to some 5...5.5 mA.
Or - leave 5.6K, as you had before - it runs great anyway.
This is just a very fine tuning ))
We can either slightly tune-up R24 || R25 for increasing it back to some 5...5.5 mA.
Or - leave 5.6K, as you had before - it runs great anyway.
This is just a very fine tuning ))
vz-x4 analyzed using RightMark Audio Analyzer.
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Wow - RMAA is just what I have been looking for to measure my amps! Just need a good sound card.
This is like the "REW" for amps. 🙂
This is like the "REW" for amps. 🙂
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?
My choice:
WinAudioMls: Audio Realtime Analyzer for Windows platform using FFT and MLS
But it's not free 😉
Still some noise components above 1KHz... however - better than before.
The board performance looks good!
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
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
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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.
