{"type_number":"6SU7","canonical_url":"https://tubeofile.com/tubes/6SU7","manufacturer":"Tung-Sol","tube_type_key":"small_signal_triode","tube_type_display_name":"Small Signal Triode","base_name":"Octal","description":"High-mu twin triode amplifier with the same general characteristics as the 6SL7GT, but featuring a low-loss phenolic (Micanol) base, minimum gas and leakage currents, and specially tested for plate current balance between the two triode units. Developed by Tung-Sol, first registered March 1944.","is_directly_heated":false,"completeness":"high","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."],"references":["https://frank.pocnet.net/sheets/127/6/6SU7GTY.pdf","https://frank.pocnet.net/sheets/127/6/6188.pdf","https://www.jj-electronic.com/images/stories/product/preamplifying_tubes/6sl7/6sl7.pdf"],"source_urls":{"r_type":null,"tdsl":"https://tdsl.duncanamps.com/show.php?des=6SU7GTY","radiomuseum":"https://www.radiomuseum.org/tubes/tube_6su7gty.html"},"raw_equivalents":["6SU7GT","6SU7GTX","6SU7GTY","6SL7GT","6SL7GTY","6113","VT-229","CV1985","6N9S","6N9C","6N9M","6188","6SL7WA","6SL7"],"equivalents":[{"type_number":"6SL7","equivalence_type":"direct","notes":null}],"similar":[{"type_number":"12SL7GT","reason":"Same electricals but 12.6V heater — not a drop-in in 6.3V circuits","has_detail_page":false}],"pins":[{"pin_number":"1","function":"Control Grid (section 2)","function_code":"g1_2","notes":null},{"pin_number":"2","function":"Anode (section 2)","function_code":"a2","notes":null},{"pin_number":"3","function":"Cathode (section 2)","function_code":"k2","notes":null},{"pin_number":"4","function":"Control Grid (section 1)","function_code":"g1_1","notes":null},{"pin_number":"5","function":"Anode (section 1)","function_code":"a1","notes":null},{"pin_number":"6","function":"Cathode (section 1)","function_code":"k1","notes":null},{"pin_number":"7","function":"Heater","function_code":"h","notes":null},{"pin_number":"8","function":"Heater","function_code":"h","notes":null}],"specs":[{"key":"Vh","display_name":"Heater Voltage","value":"6.3","numeric_value":"6.3","unit":"V","param_group":"heater"},{"key":"Ah","display_name":"Heater Current","value":"0.3","numeric_value":"0.3","unit":"A","param_group":"heater"}],"sections":[{"section_number":1,"section_label":"Triode (each section)","tube_type_key":"small_signal_triode","specs":[{"key":"Va_max","display_name":"Anode Voltage (max)","value":"250","numeric_value":"250","unit":"V","param_group":"absolute_max"},{"key":"Pa_max","display_name":"Anode Dissipation (max)","value":"1","numeric_value":"1","unit":"W","param_group":"absolute_max"},{"key":"Ik_max","display_name":"Cathode Current (max)","value":"8","numeric_value":"8","unit":"mA","param_group":"absolute_max"},{"key":"Vhk_max","display_name":"Heater-to-Cathode Voltage (max)","value":"100","numeric_value":"100","unit":"V","param_group":"absolute_max"},{"key":"Rg_max","display_name":"Max Grid Resistor","value":"1","numeric_value":"1","unit":"MΩ","param_group":"absolute_max"},{"key":"Va","display_name":"Anode Voltage (typical)","value":"250","numeric_value":"250","unit":"V","param_group":"typical_operating"},{"key":"Vg","display_name":"Grid 1 Bias Voltage","value":"-2","numeric_value":"-2","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"2.3","numeric_value":"2.3","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"44000","numeric_value":"44000","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"1.6","numeric_value":"1.6","unit":"mA/V","param_group":"typical_operating"},{"key":"mu","display_name":"Amplification Factor (μ)","value":"70","numeric_value":"70","unit":"—","param_group":"typical_operating"},{"key":"Cgp","display_name":"Grid-to-Plate Capacitance","value":"3.5","numeric_value":"3.5","unit":"pF","param_group":"capacitances"},{"key":"Cgk","display_name":"Grid-to-Cathode Capacitance","value":"2.15","numeric_value":"2.15","unit":"pF","param_group":"capacitances"},{"key":"Cak","display_name":"Anode-to-Cathode Capacitance","value":"0.9","numeric_value":"0.9","unit":"pF","param_group":"capacitances"}]}],"synced_at":"2026-04-07T19:05:02.395Z"}