So this is a mono set? I assume you recommend your tube pre, or is that coming soon too?@bjesien We've been making preamps since 1989- the MP-1 was the first balanced line preamp made for home audio.
Intrigued. Could you please point me in the direction of any credible scientific documentation which arrives at this conclusion?@pesky_wabbit This fact that the ear/brain system uses higher ordered harmonics (5th and up) to sense sound pressure is well known and you can prove it to yourself with simple test equipment. All you need is a speaker, an amplifier, a VU meter and a sine/square generator. Set the generator to sine. Run the signal into the amp and then to the speaker. Use the VU meter to show the level. Set the level to 0VU. Then cover up the meter and turn down the volume. Set the generator to squarewave output. Keep the meter covered; run the volume up until its as loud as it was before. Uncover the meter and you'll immediately see what's going on- typically the meter will be showing -20dB or less. Square waves have lots of higher ordered harmonics and sine waves have none.
On page 31 of the Radiotron Designer's Handbook (3rd edition, from the 1930s) we see that it was understood back then that the higher orders were more audible and so should not be created in large amounts for the critical (or casual) listener. Here's a link to a pdf of that tome:
https://worldradiohistory.com/BOOKSHELF-ARH/Handbooks/Radiotron-Designer%27s-Handbook-3rd-Edition.pd...You might want to read the chapters on audio power amplifier design; its quite interesting to see how well were understood the principles we use today. Keep in mind that the Radiotron was meant as a guide and is not greatly in-depth.
General Electric did a study on this in the 1960s which I read in college but I've yet to find that study on line.