The iFi iDSD PRO comes with an excellent pair of NOS (New-Old-Stock) tubes in its analog output stage. My suggestion to most everyone would be to leave them the same, as the stock sound is about as good as you will get.
I have experienced super 'syrupy' tube sound with RCA branded 5670 tubes, all the way to my current rather rare favorites.. Tesla (not the current JJ product, I am taking the real deal Tesla from back in the golden days of tubes) 6CC42's.
The iDSD PRO is highly sensitive to leaky tubes, however, so be careful when tube rolling or you will hear a brash, rough sound come forth from your speakers that will have you wondering 'what piece of gear did I break this is time?' Actually in all truthfulness if you get the volume turned all the way down fast enough, let it cool down, and remove the offending tubes all should be just fine for the next set of tubes to try.
I have experienced super 'syrupy' tube sound with RCA branded 5670 tubes, all the way to my current rather rare favorites.. Tesla (not the current JJ product, I am taking the real deal Tesla from back in the golden days of tubes) 6CC42's.
The iDSD PRO is highly sensitive to leaky tubes, however, so be careful when tube rolling or you will hear a brash, rough sound come forth from your speakers that will have you wondering 'what piece of gear did I break this is time?' Actually in all truthfulness if you get the volume turned all the way down fast enough, let it cool down, and remove the offending tubes all should be just fine for the next set of tubes to try.
TESLA 6CC42 tubes currently installed and used for this review.
excellent pair of Sylvania GOLD BRAND 5670 tubes installed.
RCA 5670 Tubes.. wonderful lush sound.