I am trying to avoid the use of discrete tones and ultimately want the playing field level so to speak so the input tones and resultant overload behavior is representative of the signal that is fed to the input of the phono. It was Chicago’s post that alerted me to this issue. His results as posted in this image gave me cause for concern on several levels.
According to these plots if I am interpreting them correctly the lowest signals input to the DUT have the most distortion and as signal level goes up (aside from the obvious clipping) the distortion goes down. This is 100% the opposite of what I would expect and I am trying to reconcile the cause of this behavior. (I’m guessing noise?)
I would simply like to recreate this set of plots with a “riaa corrected” input to the dut and see the results. Moving to using an iRiaa is of course an option but then as mentioned above I run out of signal to fully clip the stage. I am specifically trying to look at overload characteristics and while using discrete tones scaled to the right amplitude for frequency will solve all the issues, getting that info into nice clean plots is quite tedious and time consuming.
I really do appreciate this discussion and am glad you are here to support your product!
dave