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.

What 10BQ5 Sells For
MeasurePer 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 sales8

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.

Datasheets

Original manufacturer datasheets for 10BQ5, hosted by Frank Philipse's Electron Tube Data sheets.

ManufacturerDesignationDatasheet
Tung-Sol 10BQ5 PDF (645 KB)
In the Archive

Documents held here and used to write this page.