10BQ5
10BQ5 has no equivalent designation confirmed by the archive. Completed sales put the typical price at $15.04 per tube.
Description
The 10BQ5 is an output pentode designed for application in medium power hi-fi amplifiers. Except for heater characteristics and heater warm-up time, it is identical to the 6BQ5. The tube has a glass bulb, a miniature button 9-pin base (E9-1), and a coated unipotential cathode. It can be used in any mounting position. The basing diagram is JEDEC 9CV, and the outline drawing is JEDEC 6-4.
Ratings
Maximum ratings for the 10BQ5 include a plate voltage of 300 volts, a plate voltage without plate current of 550 volts, and a plate dissipation of 12 watts. The maximum grid #2 voltage is 300 volts, and without current it is 550 volts. Grid #2 dissipation is limited to 2 watts, with a peak dissipation of 4 watts. The maximum negative grid #1 voltage is 100 volts, and the maximum cathode current is 65 mA. The maximum voltage between heater and cathode is 100 volts. The maximum grid #1 circuit resistance is 1 megohm with automatic bias and 0.3 megohm with fixed bias.
Heater
The heater is rated at 10.60 volts and 0.45 ampere, with a warm-up time of 11 seconds. The Tung-Sol datasheet specifies a heater current of 450±30 mA. The Tung-Sol datasheet also states that when the heater and positive voltages are obtained from a storage battery by means of a vibrator, the maximum plate and grid #2 voltages are reduced to 250 volts and the maximum plate dissipation to 9 watts.
Capacitances
Interelectrode capacitances are as follows: grid #1 to all other elements, 10.8 pF; plate to all other elements, 6.5 pF; plate to grid #1, 0.5 pF maximum; and grid #1 to heater, 0.25 pF maximum.
Applications
A pair of 10BQ5 tubes in class AB push-pull conventional operation yields an output of up to 17 watts at 4% distortion without feedback. In single-ended operation, the 10BQ5 can obtain a power output of 5.7 watts.
| Measure | Per tube |
|---|---|
| Median | $15.04 |
| Typical range (25th–75th) | $14.00 – $56.19 |
| Most sales (10th–90th) | $8.69 – $65.00 |
| Extremes incl. outliers | $8.69 – $65.00 |
| Completed sales | 8 |
Per-tube prices from completed sales, 2026-07-30 to 2026-08-22. Matched pairs and quads are divided out. See the price index for how these move over time.
Original manufacturer datasheets for 10BQ5, hosted by Frank Philipse's Electron Tube Data sheets.
| Manufacturer | Designation | Datasheet |
|---|---|---|
| Tung-Sol | 10BQ5 | PDF (645 KB) |
Documents held here and used to write this page.
- TUNG-SOL -