EL84 N709 Gold Lion Genalex Röhren BTB matched Pair

Genalex Gold Lion N709/EL84 – BTB-matched pair for hi-fi and guitar amplifiers

This Genalex Gold Lion N709/EL84 set contains two matched current-production power pentodes. The valve uses a nine-pin B9A Noval base, operates from a 6.3 V heater supply and is identified by the current manufacturer as an N709/6BQ5-equivalent output valve for audio-frequency power stages.

Unless stated otherwise, BTB matches EL84 sets in-house at a practical plate voltage of 300 V. The pair is particularly suitable for compatible push-pull output stages using two EL84 valves or for two identically configured single-ended channels. An output stage using four EL84 valves should preferably use one matched quad rather than two independently matched pairs.

Suitable applications

• Hi-fi push-pull output stages using two EL84 or 6BQ5 valves
• Guitar amplifiers using exactly two EL84 output valves at a compatible operating point
• Stereo single-ended amplifiers using one EL84 per channel with identical channel circuits
• Service and replacement in equipment that explicitly specifies EL84, 6BQ5 or N709 valves
• New builds whose heater supply, plate and screen-grid voltages and output transformer suit the EL84 type

BTB matching and package contents

Package contents

Two current-production Genalex Gold Lion N709/EL84 valves

Selection type

BTB matched pair, selected in-house as one coordinated set of two output valves

Practical matching operating point

300 V plate voltage for EL84 sets unless the specific product states otherwise

Test system

Roetest V11, current as of 2026

Parameters considered

Plate current, transconductance, grid currents, plate resistance and acoustic checks

Technical benefit

Closely corresponding electrical loading of the two push-pull halves or closely corresponding operating values in two identically configured channels

Difference from a matched quad

A four-valve output stage is better served by one quad selected as a complete set than by two independently matched pairs

Technical data

Valve type

Indirectly heated miniature power pentode

Type designations

N709/EL84; identified by the current manufacturer as N709/6BQ5 equivalent

Production type

Current production, not a historical NOS valve

Base

Nine-pin B9A Noval

Heater voltage

6.3 V nominal

Heater current

700 to 840 mA per valve according to the current Genalex data sheet

Maximum plate voltage

300 V

Maximum screen-grid voltage

300 V

Maximum cathode current

65 mA

Maximum plate dissipation

14 W

Maximum screen-grid dissipation

2.2 W

Maximum heater-to-cathode voltage

100 V; the data sheet tests insulation at ±100 V

Maximum grid-leak resistance with cathode bias

1.0 MΩ

Maximum grid-leak resistance with fixed bias

0.51 MΩ

Data-sheet test point

Plate and screen-grid voltages of 250 V with a control-grid voltage of -6.6 V

Plate current at the data-sheet test point

40 to 54 mA

Screen-grid current at the data-sheet test point

8.0 mA maximum

Transconductance at the data-sheet test point

9.0 mA/V minimum

Single-ended power example in the data sheet

At least 3.0 W into a 5.2 kΩ plate load with no more than 10% distortion under the stated test conditions; this is not a power rating for the matched pair in a particular amplifier

Manufacturer construction features

Single-halo getter and coated plate structure

Dimensions

Maximum overall height approximately 78.5 mm and maximum envelope diameter 22.5 mm according to the current data sheet

Country of origin

Russia according to the current BTB and manufacturer listings

Pinout

Pin 1

Free

Pin 2

Control grid g1

Pin 3

Cathode and suppressor grid g3

Pins 4 and 5

Heater

Pin 6

Free

Pin 7

Plate

Pin 8

Free

Pin 9

Screen grid g2

Sound positioning

Electro-Harmonix subjectively describes the current Genalex Gold Lion EL84 in terms of soft overdrive, organic sustain and harmonic crunch. BTB subjectively positions the version as clear, neutral, spacious and dynamic. The audible result also depends on the operating point, output transformer, feedback, loudspeaker, power supply and complete amplifier circuit.

Selection and application notes

Matching does not replace verification of the operating point. In a fixed-bias amplifier, check and adjust the quiescent current after replacing the valves. A cathode-biased amplifier often has no adjustment, but its cathode current and plate dissipation should still be checked, especially in circuits that operate EL84 valves close to their limits.

The 300 V, 65 mA, 14 W and 2.2 W figures are limits from the current Genalex data sheet rather than universal recommended operating values. A valid operating point depends on the plate and screen-grid voltages, quiescent current, load impedance, cooling and operating class.

In an amplifier whose two output valves operate together, replace both old valves as a set. A four-EL84 amplifier should preferably use a matched quad. Check mechanical clearance before ordering because the manufacturer specifies a maximum overall height of 78.5 mm.

Power valves become very hot and operate with lethal voltages. Switch the equipment off, disconnect it from the mains, allow the valves to cool completely and leave bias or high-voltage work to suitably qualified personnel.

Questions about selection and use

Is the Genalex Gold Lion N709/EL84 BTB matched pair suitable for a push-pull output stage using two EL84 valves?

Yes, the Genalex Gold Lion N709/EL84 BTB matched pair is intended for compatible push-pull output stages using two EL84 or 6BQ5 valves. The heater supply, plate and screen-grid voltages, output transformer, quiescent current and mechanical clearance must suit the specific amplifier.

Can the matched pair replace an existing EL84 or 6BQ5 set?

Yes, the current manufacturer identifies the Genalex Gold Lion N709/EL84 as N709/6BQ5 equivalent. Replacement is suitable when the equipment specifies the standard EL84 or 6BQ5 type; related valves such as E84L, 7189 or SV83 should not be treated as unchecked direct equivalents merely because their bases are similar.

Should the operating point be checked after installing the matched EL84 pair?

Yes, a matched pair still requires an operating point that suits the circuit. Check and adjust the bias in a fixed-bias amplifier; in a cathode-biased amplifier, verify the cathode current, plate dissipation and heater voltage under normal operating conditions.