As the battery of the Sony TC-D5 goes down interesting harmonic distortion is created

It is tricky to capture the sweet spot.


The ticking clock from far away could be better heard through the headphones indicating an increase in information extraction.


Perhaps it is the trick that cats use. There is a paper on JASA describing 2 sinewaves stimulating a cat's ear and many many combination frequencies arriving at the cat's brain through the auditory nerve. Non linearity at work. This is why the cat goes nuts when we call her pspspspsppsssss.


Heavier analog distortion is very nice especially when one only instrument or voice is sent to a chanel. For example male singing voice sounded as a male voice reproduced through a vinyl records. That nice buzz sound.


Signal path. Setup:


Male singing voice at 2 in - Sennheiser MD211 N - Pleiades (140Ω, 41mH) filter, shunt - Pleiades V6 with Altec 4722 input transformer and Nuvistor 7586 electron tube at less than 4 volt - Sony TC-D5 pro with fading batteries - Sennheiser HD580