The Tube Amp Doctor premium selected 12AX7 / ECC83-Cz features big, warm, clean sounds with a mellow top-end when pushed to overdrive. It’s a great choice for guitar amps and HiFi alike. The ECC83-Cz is recommended if you want to emphasize punchy mids and is especially great when pushed into a fat overdrive.

The TAD™ ECC83-Cz is a miniature, high-mu twin triode with good gain, round deep bass, somewhat compressed mids and very smooth top end. Selected and recommended for guitar amps to smoothen up the tone or for HiFi to shape the body of sound more to “that” tube tone. Best for jazzy and thick clean as well as for vintage bass response. Recommended for all positions in amps with medium gain level or High-Gain Amps for V2+ positions. As for V1 in general but especially for higher gain amps or phono/audio-amps, we recommend the RT030 7025/E83CC Highgrade, T-7025-HG-TAD. The TAD™ ECC83-Cz can replace any 7025, 12AX7WA, 12AX7WB, 12AX7LPS, 12AX7EH, ECC83 or E83CC.

Q: When does a preamp tube become a Premium Selected tube?

A: All preamp tubes labeled Premium Selected have passed the following tests:

• Low Noise Test
• Microphonic Test
• Gain Test
• Sonic Tests
• Shock Tests
• Listening Tests
• Balanced Output Test