What is the 8417 vacuum tube?

The 8417 is a pentode vacuum tube designed for power (pp) applications. High-power beam tetrode..

What is a 8417 substitute or equivalent?

Direct equivalents to the 8417 include None. These share the same pinout and operating envelope, so they can usually be swapped without circuit changes — though batch-to-batch variations between manufacturers (NOS vs current production) may shift the sonic character noticeably.

What are the key specifications of the 8417?

Amplification factor μ ≈ 16, transconductance gm ≈ 23 mA/V, plate resistance rp ≈ 16.0 kΩ, max plate voltage 660 V, max plate dissipation 35 W, heater 6.3 V / 1.6 A.

Is the 8417 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 8417 as Sought-after availability. NOS (new-old-stock) examples from RCA, Mullard, Tung-Sol, GE, Sylvania and Telefunken trade among collectors; modern production where it exists comes mostly from JJ Electronic, Electro-Harmonix, Tung-Sol (New Sensor), Genalex, and a handful of small-batch makers.

What does the 8417 sound like?

High-power beam tetrode.. Sonic character also depends heavily on the circuit operating point, the surrounding tubes in the stage, and the output transformer when present — use the interactive loadline calculator on this page to explore the trade-offs.

By Jean-Michel Falligan Devergne · Reviewed May 29, 2026

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8417 Pentode Vacuum Tube

Pentode6.3V / 1.6AOctalSPICE

SourceSylvania 8417 datasheetReviewed2026-05-29StatusDataModelCalcModelKoren pentodePDF

Power pentode delivering up to 35W in pentode, UL, or triode mode

Datasheet ↗SPICE

8417 — GE — pentode vacuum tube — (1962)

16.0kΩ

23.0mA/V

22.0pF

0.9pF

9.00pF

GAIN16%

POWER88%

DRIVE84%

LINEARITY92%

SPECIFICATIONS

Heater6.3 V · 1.6 A

Max Plate Voltage660 V

Pa max35 W

Gain Factor16

gm23 mA/V

rp16.0 kΩ

Inter-electrode capacitances

Cgk22 pF

Cgp0.9 pF

Cpk9 pF

PinoutOctal

Era1962

RaritySought-after

HEATER6.3V / 1.6A

MAX PLATE660V / 35W

BASEoctal

Source datasheets

2 manufacturer datasheets cross-checked for 8417

2 verified

EXECUTIVE SUMMARY

The 8417 is a indirectly-heated pentode from GE, introduced around 1962. It provides a gain factor (μ) of 16 with 16.0kΩ plate resistance. Commonly used in power (pp) applications. High-power beam tetrode.

APPLICATIONS

Power output

Generic pentode power (pp) stage

• PA/public address

HISTORY

Introduced1962ManufacturerGE

Late Production

8417 Datasheet

Local mirror · PDF

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METRIX TESTER

Test this tube on a Metrix

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