I have been messing around more. I have a hybrid line stage I made similar to this phono stage that is dead quiet. The line stage has the opamp buffer on the input and output and two resistors to set the gain in the long tail circuit.
The phono is the same thing only with a second long tail circuit. What do you think for noise and drift due to tube characteristics? I have been using trial and error with the feedback resistors and caps for flat RIAA. I am having no luck. Any suggestions?
The phono is the same thing only with a second long tail circuit. What do you think for noise and drift due to tube characteristics? I have been using trial and error with the feedback resistors and caps for flat RIAA. I am having no luck. Any suggestions?
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The first stage of LME49860 is useless with the following reason.
No voltage gain ( 0dB gain ) > No benefit for noise
But the last stage of LME49860 is useful due to low
output impedance.
Regarding to RIAA equalizer CR values, please send the
TINA TSC file so that I will implement simulation.
No voltage gain ( 0dB gain ) > No benefit for noise
But the last stage of LME49860 is useful due to low
output impedance.
Regarding to RIAA equalizer CR values, please send the
TINA TSC file so that I will implement simulation.
I am aware the input buffer is useless. There are two of them on each chip and needed to do something with the second 🙂
I did TINA simulation. I modified the original schematic
as following reasons.
*Frequency Response is not flat.
> Change the CR values to another Japanese' (yesterday's my post)
*Voltage Gain is only 30dB
> I modified the first stage of LME49860 has 12dB gain
The results are shown in the attached photos.
as following reasons.
*Frequency Response is not flat.
> Change the CR values to another Japanese' (yesterday's my post)
*Voltage Gain is only 30dB
> I modified the first stage of LME49860 has 12dB gain
The results are shown in the attached photos.
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