Same electricals but 12.6V heater — not a drop-in in 6.3V circuits
Electrical Specifications
Absolute Maximum
Anode Voltage (max)Anode Voltage (max)250V
Anode Dissipation (max)Anode Dissipation (max, per section)1W
Cathode Current (max)Cathode Current (max)8mA
Heater-to-Cathode Voltage (max)Heater-to-Cathode Voltage (max)100V
Notes
The 6SU7GTY is a special-quality 6SL7GT selected for balanced sections, low gas, and low leakage. The Tung-Sol datasheet specifies plate current difference between sections of ±0.1 Vdc (initial) and ±10 mAdc (after 500-hour life test), making it well-suited for balanced DC amplifiers and low-level audio stages.
The 6SU7GTY max plate voltage (250V per Tung-Sol 1946 datasheet) is lower than the 6SL7GT (300V per JJ). The 6188/6SU7WGT premium version raises this to 275V. When substituting a 6SL7GT with a 6SU7GTY, verify the circuit does not exceed 250V on the plates.
Heater-cathode voltage should be kept as low as possible per the 6SU7GTY datasheet. The 6188/6SU7WGT datasheet specifies ±100V Vhk_max.
Soviet equivalents 6N9S (6Н9С), 6N9C, and 6N9M share the same octal basing and electrical characteristics.
Pin Layout — Octal
1Control Grid (section 2)
2Anode (section 2)
3Cathode (section 2)
4
Socket-Compatible Tubes ⚠ Not electrically compatible