Remember you lose 40% of the amplification factor of a 12AX7. The At7 is considered by many a bad audio tube because it was originally engineered to work in oscillators. As an input tube however it can work very well because it is a very good phase splitter. It is apparently a very versatile tube eliminating the need evidently for a separate phase. A fair number of engineers use them.
I used a variety of 12volt 9 pins in the input section of a 40wpc ultralinear amp using a very classic Mullard long tail circuit. I found some tubes just didn't sound so great but all of them worked well enough.
I have no idea what purpose it serves in a Kora . Be warned I am a technical know nothing
I used a variety of 12volt 9 pins in the input section of a 40wpc ultralinear amp using a very classic Mullard long tail circuit. I found some tubes just didn't sound so great but all of them worked well enough.
I have no idea what purpose it serves in a Kora . Be warned I am a technical know nothing