6AS7
6AS7 has no equivalent designation confirmed by the archive. Completed sales put the typical price at $30.00 per tube.
General Description
The 6AS7 is a glass-envelope, dual power triode with high transconductance and high plate current capacity. Each triode has an indirectly-heated, oxide-coated unipotential cathode. The tube is manufactured in the Svetlana factory in Russia.
Construction and Ratings
The Svetlana datasheet gives maximum ratings per triode: DC plate voltage 250 V, grid no.1 (control) voltage -150 V, DC cathode current 130 mA, plate dissipation 13 W with convection cooling, and bulb temperature (surface hottest point) 250 degrees C. Maximum cathode-to-heater potential is plus or minus 300 V. Heater voltage (AC or DC) is rated at 5.7 V minimum, 6.3 V nominal, and 6.9 V maximum, with a nominal heater current of 2.5 A.
The base is JEDEC 8BD, octal 8-pin. Maximum dimensions are 140 mm (5.51 in.) height and 52 mm (2.05 in.) diameter, with an approximate net weight of 90 g (3.2 oz.). Cooling is by convection. When mounting horizontally, pins 1 and 8 must be in the same horizontal plane.
Electrical Characteristics
The Svetlana datasheet gives typical transconductance as 5500 microsiemens and plate resistance as 280 ohms. Maximum direct interelectrode capacitances are: grid to cathode 8 pF, plate to cathode 3 pF, and grid no.1 to plate 11 pF.
Applications
The 6AS7 is intended for low distortion audio frequency power amplification service in either single or push-pull/parallel tube applications. The Svetlana datasheet gives a typical class A operation for two triodes in push-pull, with plate voltage 250 V, zero signal plate current 80 mA, max signal plate current 110 mA, cathode resistor (each triode) 1250 ohms, peak grid-to-grid AF signal 250 Vp-p, effective load resistance 6000 ohms, and power output 10 W. The 6AS7A variant was originally designed as a series pass tube in regulated power supplies.
| Measure | Per tube |
|---|---|
| Median | $30.00 |
| Typical range (25th–75th) | $18.95 – $56.03 |
| Most sales (10th–90th) | $12.00 – $92.16 |
| Extremes incl. outliers | $2.44 – $737.35 |
| Completed sales | 149 |
| Brand | Median | Range | Sales |
|---|---|---|---|
| RCA | $27.99 | $17.28 – $48.65 | 75 |
| GE | $19.45 | $9.95 – $35.49 | 14 |
| Sylvania | $32.48 | $28.95 – $65.82 | 12 |
| Svetlana | $33.37 | $25.70 – $37.50 | 12 |
| Tung-Sol | $85.00 | $75.00 – $603.67 | 7 |
| Chatham | $56.90 | $48.80 – $158.75 | 4 |
| Condition | Median | Sales |
|---|---|---|
| NOS | $36.50 | 74 |
| used | $25.37 | 54 |
Per-tube prices from completed sales, 2026-02-05 to 2026-10-17. Matched pairs and quads are divided out. See the price index for how these move over time.
Original manufacturer datasheets for 6AS7, hosted by Frank Philipse's Electron Tube Data sheets.
| Manufacturer | Designation | Datasheet |
|---|---|---|
| Svetlana | 6AS7 | PDF (72 KB) |
Documents held here and used to write this page.
- **Svetlana 6AS7 Dual Power Triode for High Performance Audio Applications**