FYIW, I did the same experiment. Preamp at 40 - SPL shows 72db. Unplug Typhon - still 72db. Play one minute of music with high dyanmic range. Highest peak in one minute is 77db. Unplug tyhpon, some result 77db.
have you tried with pink noise?
BTW to all you scientists feel free to buy whatever equipment you want. I'm a retired doc and a totally different science so for my need my good old Radio Shack SPL Meter serves me just fine. I'm reporting what I heard with another listener (who BTW IMO is the most critical listener I have ever known in this hobby and is not only a doc like me but so also the scientist I'm not) and he heard the difference as plain as day as me.
Now, you can argue all you want about the lack of science.....I agree
However two of us heard it and in both of our opinions it was a 4 Db difference. I also said that I have no explanation. I would be happy to have you come by for a listen and we can put our thinking caps on but in the meanwhile I was there and you weren't. It's easy to pontificate. We've all done that. I have no explanation nor does Marty. I'm only the messenger. I posted this because I anticipated it would generate a lot of discussion. It has. There are 2 other users here who have found what I have and edorr who heard no difference. Perhaps that is why he is selling his Typhon. Marty BTW also has a Triton but no Typhon and like everyone here was very skeptical as to my findings. He hasn't heard my system since my adding the Shunyata gear but he is quite familiar with a Triton in his system. As previously posted, after listening for a few hours, Marty then said, OK, you know I can't leave until I compare the system without the Typhons in the AC duplex of my amps and then the Typhon plugged into my Triton. It was both our perceptions that without the Typhons the preamp gain control had to be increased by 4 Db in order to restore what we were hearing when the Typhons were in the system