Silicon Tube Damper for 12AX7, EL84

Premium medium-Mu Twin Triode for use in preamplifier.

TT Selection: Balanced
Both systems with balanced gain

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.

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.

TT Selection: V1 - Low Noise
This tube is selected for sensitive input stages (V1)

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.

• Type: LIH/125 Stranded wire - halogen free
• Conductor: stranded copper - tinned
• Conductor strands: 16 x 0.2 mm
• Insulation: TPE-S (12Y), flammable
• Cross sectional area: 0,5 mm²
• Outer Ø: 1.6 mm
• Temperature Range  
• static / dynamic: -40 to +125°C / -25 to +125°C
• Operating voltage: 900V
• Insulation resistance: min. 200MΩ x km at +20°C

• Type: LIH/125 Stranded wire - halogen free
• Conductor: stranded copper - tinned
• Conductor strands: 16 x 0.2 mm
• Insulation: TPE-S (12Y), flammable
• Cross sectional area: 0,5 mm²
• Outer Ø: 1.6 mm
• Temperature Range  
• static / dynamic: -40 to +125°C / -25 to +125°C
• Operating voltage: 900V
• Insulation resistance: min. 200MΩ x km at +20°C

• Type: LIH/125 Stranded wire - halogen free
• Conductor: stranded copper - tinned
• Conductor strands: 16 x 0.2 mm
• Insulation: TPE-S (12Y), flammable
• Cross sectional area: 0,5 mm²
• Outer Ø: 1.6 mm
• Temperature Range  
• static / dynamic: -40 to +125°C / -25 to +125°C
• Operating voltage: 900V
• Insulation resistance: min. 200MΩ x km at +20°C

• Type: LIH/125 Stranded wire - halogen free
• Conductor: stranded copper - tinned
• Conductor strands: 16 x 0.2 mm
• Insulation: TPE-S (12Y), flammable
• Cross sectional area: 0,5 mm²
• Outer Ø: 1.6 mm
• Temperature Range  
• static / dynamic: -40 to +125°C / -25 to +125°C
• Operating voltage: 900V
• Insulation resistance: min. 200MΩ x km at +20°C

• Audio: 5 W
• Max. DC: 45 mA
• Pri. Inductance: 8,97 H

Kit for TT PSU Mini

The kit includes all components except a powertransformer and a choke for building PSU for tube amps. If you want to use a choke instead of the 5 W resistor than you must order the choke that you need separately.
The PSU can handle max 700 V DC at out B1 and B2, 450 V DC at out B3 and is recommended for tube amps up to 50 Watt. The size of the PSU is 97 x 55 mm only and has a high of ca. 40 mm.

Please refer the attached schematic for more infos about the layout and design of the PSU.

Tip: use Duncanamps' PSU Designer to simulate and calculate power supplies.

Files:

• Document

• Type: Tubular Metalized Polyester Film Capacitors
• Voltage Rating: 630 V
• Tolerance: +/- 10%
• Operating Temperature Range: - 40°C / + 85 °C
• Termination Style: axial
• • Non-inductive
  • Self healing windings.
  • Similar to the Mallorys 150-Series

• Type: Electrolytic capacitor
• Capacitance: 220 µF
• Voltage Rating: 63 V
• Tolerance: - 10 % / +30 %
• Operating Temperature Range: - 40°C / + 85 °C
• Dimensions: Ø 15 mm x 20 mm
• Termination Style: axial

Images are for reference only. See Product Specifications

• Type: HV ceramic disk capacitor
•   Epoxy resin molding
•   (insulating and flame retardant)
• Voltage Rating: 2 kV
• Tolerance: - 20 % / +20 %
• Operating Temperature Range: - 40°C / + 85 °C
• Dimensions: 3 mm x 7 mm
• Grid: 7,5

ECC82 / 12AU7 medium gain pre-amplifying double triode.
Provides a very smooth sound with well-defined tones suitable for audio and guitar amplifiers.

Files:

• Datasheet