What is the DCC90 vacuum tube?

The DCC90 is a triode vacuum tube designed for preamp applications. Battery dual triode..

What is a DCC90 substitute or equivalent?

Direct equivalents to the DCC90 include 3A5. 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 DCC90?

Amplification factor μ ≈ 15, transconductance gm ≈ 1.8 mA/V, plate resistance rp ≈ 8.3 kΩ, max plate voltage 135 V, max plate dissipation 1 W, heater 1.4 V / 0.22 A.

Is the DCC90 still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the DCC90 as Rare 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 DCC90 sound like?

Battery dual triode.. 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.

DCC90 Triode Vacuum Tube

Also known as 3A5

Medium-gain triode for driver and line stage applications

TriodeHeater 1.4 V · 0.22 A7-pin MiniatureMullard 1955

Plate dissipation: 1W
Max plate voltage: 135V
Amplification factor: 15
Transconductance: 1.8mA/V
Plate resistance: 8.3kΩ

DCC90

Characteristics

Datasheet values, once each. Every value cites its sheet.

HeaterDirectly heated

Specifications of DCC90 — Heater
Heater voltageVh	1.4 V
Heater currentIh	0.22 A

Limiting valuesDatasheet maximum ratings — not to be exceeded

Specifications of DCC90 — Limiting values
Plate voltageVa max	135 V
Plate dissipationPa max	1 W

Mechanical

Specifications of DCC90 — Mechanical
Base	7-pin Miniature
Rarity	Rare
Pinout

Small signalDatasheet parameters at the reference operating point — not limits

Specifications of DCC90 — Small signal
Transconductance	1.8 mA/V
Plate resistance	8.3 kΩ
Amplification factor	15

Capacitances

Specifications of DCC90 — Capacitances
Grid–cathode	0.9 pF
Grid–plate	3.2 pF
Plate–cathode	1 pF

Charactereditorial reading, not a measurement

Specifications of DCC90 — Character
Gain	15%
Power	3%
Drive	92%
Linearity	93%

datasheet cited · model or editorial reading · catalogue value, no citation attached yet · nothing invented

Typical operation

Canonical operating pointModel

B+: 125 V
Load: 17 kΩ
Va: 75 V
Ia: 3.33 mA
Vg: -3 V
Pd: 0.25 W
Gain: 22.4 dB

At Q: Norman Koren
μ: 17.4
gm: 1.75 mA/V
rp: 9.9 kΩ

Design a stage →

Using this tube

Applications

Voltage amplifier
Line stage

Generic triode preamp stage

Hi-Fi stereoHeadphone amp

Replace or compare

Sources

By Jean-Michel Falligan DevergneReviewed May 29, 2026Source : Tung-Sol 3A5 / DCC90 datasheetActive model : Norman Koren

Manufacturer datasheets

2 manufacturer datasheets cross-checked for DCC902 verified

DCC90 DatasheetLocal mirror · PDF

SPICE models

Revision and verification status

Source: Tung-Sol 3A5 / DCC90 datasheet
Reviewed: 2026-05-29
Status: DataModelCalc
Model: Norman Koren

Context

The DCC90 is a directly-heated triode from Mullard, introduced around 1955. It provides a gain factor (μ) of 15 with 8300Ω plate resistance. Commonly used in preamp applications. Battery dual triode.

History

Introduced: 1955
Manufacturer: Mullard
Era: Golden Age

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