To Aesthetix users

Hi Patrick,

I have been following your progress with the IO problem. I am a relatively new owner of the IO Signature.

I was wondering if you ever left the IO on for a full day, such as 7AM until midnight, for example...I did one day and noticed at the end of the day that the IO was whistling a high pitched sound...according to my searches it sounds like tube bias getting out of whack or something related to that...how do we test tubes to see if they are bad or going bad, the IO has so many that it will take time..I do not have any problems now, been using the IO for several hours a day, not all day marathons like last week.
Thanks,
Audioquest4life

Hi AQ4life,

I leave the Io on all the time. This is recommended by Aesthetix and longtime users here such as Albert Porter. Best for sound and for tube life.

I've never heard the whistling high-pitched sound. Do you know if your Mills resistors (used in the first batch of Ios -- they turned out to be bad) have been replaced by Roedersteins? It's a free upgrade from Aesthetix.

Aside from that, I'd call Aesthetix. It sounds like you'll have to send the unit in, unfortunately. Unless it's just a bad tube somewhere. You should switch tubes from L to R starting with the front end gain pairs (12AX7LPs) and if the whistling switches channels, you may have isolated your problem tube. Remember to turn off before switching.

Thanks for the reply. I turn off the IO after every listening session. I am stationed in Germany and electricity is very expensive here.

The problem is not one that has ever popped up before. I do not need to send it off as the problem has not reproduced itself. I will let the IO stay on this weekend to see what happens.

V/r
Audioquest

BTW...nice system