Hi ,
I have an Io with volume controls and two supplies. I use original Mullards in the Io. Tighter than with the original Electro Harmonix.
They test like new compared to another NOS Mullard for reference after being in for about 4 years.
I pull all the tubes in the Io and power supplies at least 2x per year to clean the pins and "very very lightly" condition them with deoxit. WOW.. you should try it along with the IEC connector and fuses caps.
The 12AX7s in mine are NOS RCAs of which I bought several sleeves from ebay years ago. I routinely test and replace those as necessary but the NOS last for years as well.
I would not punch holes in the case unless I got a spare one.. not worth it IMO to devalue the piece. You can try the KT66s - I found them "rounder" sounding than the EL34s- I tried original GEC KT66s YMMV and all that.
Good Luck
I have an Io with volume controls and two supplies. I use original Mullards in the Io. Tighter than with the original Electro Harmonix.
They test like new compared to another NOS Mullard for reference after being in for about 4 years.
I pull all the tubes in the Io and power supplies at least 2x per year to clean the pins and "very very lightly" condition them with deoxit. WOW.. you should try it along with the IEC connector and fuses caps.
The 12AX7s in mine are NOS RCAs of which I bought several sleeves from ebay years ago. I routinely test and replace those as necessary but the NOS last for years as well.
I would not punch holes in the case unless I got a spare one.. not worth it IMO to devalue the piece. You can try the KT66s - I found them "rounder" sounding than the EL34s- I tried original GEC KT66s YMMV and all that.
Good Luck