NOS Tubes For VAC Renaissance Mk III

The 5814 and 7730 CBS Hytron are excellent examples of premium 12AU7.

Telefunken has long been an audiophile favorite for the 12AX7. Tele 12AX7 was my all time highest performer for both Aesthetix line and phono stages.

The 5814 is a military version and more rigid than standard 12AU7, typically improving signal to noise and reduction of microphonics.

Regardless of what you choose, low noise, low microphonics and good matching are important for any preamp.

Other popular choices are Amperex Bugle Boy from late 1950s and Siemens. The difficult part is knowing what each of these sound like in the circuit and then choosing which best suits your need.

Unfortunately the only way to find that out is buy and try. The good news, these tubes continue to go up in value, so if it's not perfect for this application you have a solid investment.

I have hundreds on hand in my collection.

My favorite 12AU7 is the 7316 Amperex which is a drop in sub. They were an early "computer" tube made only at the Heerlen Dutch Phillips factory in the late 50's to mid 60's. They are often labeled as H/P etc. They are a very extended, crystalline, halographic and transparent tube. For 12AX7s it really comes down to some compromise. I don't know a "do it all tube" but my favorite is the well loved Sylvania triple mica blackplate 5751, which has most of what you want. The GE 50s TMBP 5751 has more pronounced bass. A low noise all roud clean and clear sound may be best found in the rare windmill getter mid 60s Ratheon 5751, as well as the Telefunken 12AX7 as suggested above

Or, if you don't want to take risk on NOS tubes and if they are really new, try the top quality choice of Psvane. I am very pleased with the 12AU7's and KT-88 power tubes and a friend re tubed his phono with 12XA7's and finds them very quiet and very musical. My experience with the KT-88s and 12AU7's is similar.

EAT cool valve 12xA7 and 6922s are AWESOME. running a pair in my GAT preamp. wonderful