Thiel Owners

With both speakers it could be a room mode or other boundary effect. Test it by changing locations in the room.

I played around with test tones on my 3.7s and heard some mild vibration in the crossover.  Something is resonating down there but I've never heard it with anything other than the test tone cd so I don't worry about it.  Test tones can do funny things.  When I bought a big sub and was running frequency sweeps I heard a loud weird sound upstairs that scared me.  Turned out the pan in the oven was going crazy with a particular frequency played loudly by the sub.  Never noticed that with anything other than test tones either.  All sorts of stuff can start resonating with a continuous signal at a particular frequency.  Since music doesn't normally contain long continuous single frequency notes like that you'll likely never excite those resonances to near the degree you can with tones.

agree with jon.

Test tomes resulted in weird noises, both earlier 3.5s and now the 2.7s. 

Thank you jon-5912 and brayeagle 

I feel relieved and I to have only heard it with the test CD .

I'll be running it again next week when I replace 
the recitifiers on the amp that are faster and have a softer recovery  .



 

1:04 on the Ayre IBE long glide tone is ~28 Hz. Charles Hansen posted the formula on audioasylum.

What caps did you replace? In the 2.7s?