JJ 12AX7 / ECC83S Selected GOLD

JJ's version of the ECC81/12AT7 tube type with a warm and soft sound. Often used for phase inverters or reverb drivers.

Files:

• Datasheet

Very linear working 12AX7 / ECC83 with long anode plates and spiral heating, which makes the tube less sensitive to interference from AC heating.
We recommend this tube for audio and high-end amps as well as for "modern" Fender amps with more overdrive, but also as an input tube in old Marshall JCM800s.

Note: Tubes equipped with long plates are commonly associated with a "warmer" or "richer" sound, whereas those with shorter plates tend to deliver a "tighter sound". However, tubes featuring long plates exhibit increased sensitivity to vibrations and mechanical disturbances, rendering them less ideal for critical applications.

Files

• Datasheet

Sweet and warm sounding preamp tube with high gain. We recommend this tube for guitar/bass amps.

Files:

• Datasheet

Bias probe for indirect measurement of quiescent bias current of a tube. The adapter is inserted between the tube and the socket and gets connected to a standard voltmeter (not included). Pay attention to the quality of the measuring device and sufficiently charged batteries!

The quiescent current is measured indirectly via a precision resistor integrated in the adapter. The advantages of this measuring method are harmless voltages at the measuring plugs, which are in the mV range, as well as short ways for the current, since it does not need to be fed through the measuring device (common practice with many measuring adapters of Far Eastern production). As a result, there is no risk of oscillations of the amplifier which can lead to possible damage of the tubes or the amplifier itself.

Note: This adapter cannot be used when additional tube brackets are installed. These must be removed before using the measurement adapter and reattached after the measurement is complete.

Procedure for the measurement

Determine the resistance of the adapter, including the measuring leads. To do this, connect the adapter to the meter, but do not plug it between the tubes and the amplifier, yet. Select the measuring range “Ohm” on the meter and note the measured value, e.g. 1,1 ohms.

For the final measurement insert the adapter between the tube and the currentless amplifier and connect it to the meter, select the measuring range mV and switch on the amplifier. When the amplifier has reached a stable operating condition, read the value in mV from the meter and calculate the quiescent current based on Ohm's law.

Example:
measured voltage = 47 mV, resistance of the adapter = 1,1 ohms.
Formula (I = U / R) or in this case:
bias current (in A) = measured value (voltage in V) / measured value (resistance in ohm)
0.047V / 1.1 ohms = 0.042A or 42mA respectively

For the calculation of the correct bias current as well as further information on the bias measurement, please refer to further documents or the bias setting instructions in the info area, as well as the manual of the amplifier itself.

This measuring adapter is suitable for all EL34, 6L6, 6550, KT88, 6V6, 6CA7 and other tubes with the same pin layout.

Attention high Voltage! Measurements and work on tube amplifiers should only be carried out by qualified persons.

TT Selection: Balanced
Both systems with balanced gain

JJ's version of the ECC81/12AT7 tube type with a warm and soft sound. Often used for phase inverters or reverb drivers.

Files:

• Datasheet

Wire Silicon, SiAF

• Insulation: Silicon
• Operation Voltage: 500 V
• Test Voltage: 2000 V
• Operating temperatures:    –50 bis +180 °C
• Packing:: 5 m
• Cross-Section: 0,5 mm²
• Outer Diameter: 2,1 mm
• Stranded wire structure: 16 x 0,20 mm, tinned copper

• Length: 100 mm
• Width: 2,5 mm
• color: transparent
• Set of 100 pcs

• Length: 100 mm
• Width: 2,5 mm
• color: black
• Set of 100 pcs

• Length: 200 mm
• Width: 2,5 mm
• color: transparent
• Set of 100 pcs

• Length: 300 mm
• Width: 3,5 mm
• color: transparent
• Set of 100 pcs

Single tube, not matched

Totally Tweed! The preferred OEM tube of ’50s-era Fender Tweed Champ and Deluxe amplifiers The Tungsol 6V6 has a geometry designed to safely handle the higher voltages used in guitar amps – plus heavier plate and grid materials. The result.. better mids and bottom while keeping the smooth top of the classic 6V6’s. The Tungsol 6V6 breaks up evenly from low E to high up the neck. Blues players will LOVE these tubes for the way they sing!

Files:

• Datasheet

DOUBLE ANODE RECTIFYING TUBE
Suitable for all Hi-Fi and Guitar/Bass amplifiers.

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: Balanced
Both systems with balanced gain

Sweet and warm sounding preamp tube with high gain. We recommend this tube for guitar/bass amps.

Files:

• Datasheet