A good multitone test will stress an audio device in more meaningful ways. Two issues however- first is getting tone sets that don't have harmonics and IM produts on top of other tones. Second is the diagnostic component- figuring out where the circuit needs attention from the frequency domain is difficult at best. The residual from a notch can reveal a lot about where in the cycle and where in the circuit the non-linearity lies. I'm attaching some info on "Spectral Contamination" that may be helpful.
Demian,
Thanks, from all of us!
I've been using the "NID" multitone test pattern as generated in REW for some simulations in LTspice. It's really interesting how some preamp and amp designs look pretty similar when simulated for harmonic distortion yet can be 10 dB or even 20 dB apart in the multitone performance.
But, I'll try these.
Thanks, from all of us!
I've been using the "NID" multitone test pattern as generated in REW for some simulations in LTspice. It's really interesting how some preamp and amp designs look pretty similar when simulated for harmonic distortion yet can be 10 dB or even 20 dB apart in the multitone performance.
But, I'll try these.
OK, I think I got it right.
This is a simulation of the simplest circuit I can think of. Two 2SK170BLs run at Idss, with one as the current source and one as the buffer. 15 VDC rails. 1 Vrms total input voltage to 10K load.
I won't belabor this, because it's the wrong forum thread, but wanted to show an example of the Jon Risch Phi 12 multitone test. The floor doesn't include any circuit noise - only calculation "noise".
This is a simulation of the simplest circuit I can think of. Two 2SK170BLs run at Idss, with one as the current source and one as the buffer. 15 VDC rails. 1 Vrms total input voltage to 10K load.
I won't belabor this, because it's the wrong forum thread, but wanted to show an example of the Jon Risch Phi 12 multitone test. The floor doesn't include any circuit noise - only calculation "noise".