Main page » Tubes » Electro Harmonix » EH 7025 (12AX7 / ECC83 HQ)

EH 7025 (12AX7 / ECC83 HQ)

Electro-Harmonix has released a low noise, low microphonic version of the 12AX7 that meets all specifications required for the tube to be designated 7025. The original 7025 tube was a 12AX7 that was tested and selected for the lowest noise and microphonics for use in the critical first preamp stages of amplifiers where noise and microphonics could be an issue. In order to ensure that the 7025 specification is consistently met, Electro-Harmonix has redesigned the structure of the 12AX7 and has implemented construction techniques to ensure the absolute lowest noise and microphonics possible. In all samples tested, noise and microphonics could not be detected.

The Electro-Harmonix 7025EH has a mid-range that gives clarity and definition to the sound and a smooth top end for warmth and balance. With these characteristics, along with the exceptionally low noise and low microphonics, the Electro-Harmonix 7025EH will work equally well in vintage and modern high-gain guitar amplifiers, as well as sensitive phono preamps.

Safety Information

Safety Information for Vacuum Tubes

For all electrical, electromechanical and mechanical components, the specifications and operating parameters arising from the respective type standard generally apply.
Further information, where available, can be found in the respective data sheets and product descriptions included with the product.

General Information

NOT SUITABLE FOR CHILDREN - choking hazard due to small parts
NOT SUITABLE FOR UNTRAINED PERSONS - danger to life due to high voltages
The safety and processing requirements applicable to the component must be observed
CE conformity applies only when installed professionally
Warranty becomes void in case of improper handling
The operator is responsible for proper installation
Local regulations and VDE provisions must be complied with
Never exceed the rated power
Never exceed the rated voltages and currents

Required Expertise

Use of measuring instruments (multimeter, oscilloscope) and evaluation of measurement results
Safe handling of high voltages (up to 500V and more)
Reading and understanding circuit diagrams
Selection of appropriate tools
Knowledge of electrical components and their characteristics
First-aid knowledge for electrical accidents
Knowledge of VDE regulations and safety requirements

Amplifier Tubes

Hazard due to high voltages
Hazard due to very high heat generation
Hazard due to glass breakage
Hazard due to UV radiation in case of defective tubes

Manufacturer

Herstellerinformationen | Manufacturer Information

New Sensor Corporation, 32-33 47th Avenue, Long Island City, NY 11101, USA

EU-Wirtschaftsakteur | EU Economic Operator
Tube-Town GmbH, Rumbergring 37, 66969 Lemberg, Germany, info@tube-town.de

Customer reviews (2)

Essential information about customer reviews We do not verify that the published reviews come from such consumers who have actually used or purchased the rated goods or services. All reviews, i.e. positive and negative, are published. No reviews that are unobjective, offensive or unrelated to the product will be published.

Laurent S., 01/16/2021

Top tube to get rid of microphony issue without having to make compromises on the tone. Works perfect in a Friedman Smallbox clone in V1 position.

Recommended products:

Socket Noval Ceramic, Chassis w/ mounting bracket

Type: Noval Socket
Version: Ceramic Chassis mount
w/ mounting bracket
Termination Style: solder lugs
for Tube Type: 12AX7, 12AT7, 12AU7, EL84, EZ81, EL844 etc.

0,75 €

Socket Noval Ceramic w/mounting bracket - GOLD

Type: Noval Socket
Version: Ceramic Chassis mount
w/ mounting bracket Gold
Termination Style: solder lugs Gold
for Tube Type: 12AX7, 12AT7, 12AU7, EL84,
EZ81, EL844 etc.

1,29 €

Silicon Tube Damper for 12AX7, EL84

Vacuum Tube Damper made of silicon, helps to reduce noise and rattle of vacuum tubes. But it will not turn a bad tube into a good tube.
If a higher level of damping is needed, than use more than one damper per tube.

Inner diameter ca. 22 mm
Can not be used with JJ 12AX7 and other JJ preamp tubes with similar diameter and JJ EL84 and JJ EL844
Price per damper

BEFORE ordering check the exact outer diameter of the vacuum tubes and compare it with the diameter of the damper to make sure that the damper fits.

0,45 €

Customers who bought this product bought also the following products:

TT 12AX7 / ECC83 Classic

Tube-Town 12AX7 / ECC83 Preamp-Tube

The TT12AX7 impresses with its fine and detailed reproduction of the highs, which is maintained even at high amplification levels. Due to a higher H3 part, the TT12AX7 sounds significantly cleaner than many other 12AX7/ECC83 tubes, which makes the bass range appear much tighter. We therefore especially recommend this tube for styles such as clean, crunch, and metal, where high amplification and clear transparency are required.

Electrical Characteristics

Heater voltage (Uf): 6.3V or 12.6V
Heater current (If): 300mA at 6.3V, 150mA at 12.6V
Anode voltage (Ua): Maximum 300V
Grid voltages (Ug1): -2V (typical)
Grid voltages: -50V to 0V
Anode current (Ia): 1.2mA (typical)
Anode power dissipation: Maximum 1W per triode
Anode resistance (ra): 62.5kΩ
Amplification factor (μ): 100
Transconductance (S): 1.6mA/V
Input capacitance (Cin): 1.6pF
Output capacitance (Cout): 1.6pF

Mechanical Characteristics

Socket: B9A (Noval)
Number of pins: 9

Pin Configuration

1 Anode (Triode 1)
2 Grid (Triode 1)
3 Cathode (Triode 1)
4 Heater (f)
5 Heater (f)
6 Anode (Triode 2)
7 Grid (Triode 2)
8 Cathode (Triode 2)
9 Center Heater (f)

Application Notes

Heater operation: The tube can be operated with 6.3V or 12.6V, depending on the circuit design.
Grid resistors: It is recommended to use grid resistors of at least 1MΩ to ensure stable functionality.
Coupling capacitors: Capacitors with low capacitance (typically 0.1µF) are recommended to minimize high-frequency interference.

19,50 €

TT Diffusor 10"

Universal size for 10" speakers
Dome diameter: 80 mm

As the frequency increases, the radiation of a loudspeaker is increasingly focused on its center. If the listener is in this beam, the sound is extremely harsh and biting; if one moves to the side of it, the sound becomes significantly darker and treble components are partially missing.
To reduce this behavior, a diffuser is used. This sits directly in the beam of the speaker and deflects the high frequencies very strongly, it breaks the "beam". This makes the sound much fuller and more balanced.

Hear the Diffusor in action on ->YouTube (made by one of our customers, Thanks !)

14,75 €