JJ 6550 - SEXTET

2 tubes, matched as pair

Mullard reincarnated. With the EL34EH, Marshall amp owners can recreate the balanced tone, deep, tight bass, sweet mids, and well-defined highs of the original equipment Mullards. Innovative design and precision construction give the EL34EH exceptionally smooth and an ideal balance of pleasing even-order harmonics while virtually eliminating undesirable odd-order harmonics.

Files:

• Datasheet

Resistor Metaloxide 2 Watts

• +/- 5% tolerance
• -55° C to 240° C operating range
• Max 500 V
• Excellent flame retardant coating
• Different manufacturers

Please note:
These resistors have a very small form factor:
red: l = 10 mm, d = 3.9 mm
green: l = 11.5 mm, d = 4.5 mm

Warm and balanced overall sound, paired with high resolution and brilliance, which is why the TT12AT7 achieves the best results in both instrumental and audio/high-end amplifiers.

Features:

• Warm and balanced sound
• Excellent sound resolution and brilliance
• Ideal for instrumental and audio/high-end amplifiers

Hint;
Often, 12AU7 and 12AT7 types are used instead of 12AX7 tubes in order to either reduce the overall power of the amplifier or just take back the overdrive of the preamp. Especially the 12AU7 brings a very large tonal difference compared to a 12AX7, which is usually much greater than when switching from a 12AX7 to 5751 or 12AT7.

When using a 12AU7 in a driver stage that is normally designed for 12AX7, the overall power of the power amp is usually reduced. How big this difference is depends on the amplifier or circuit. For example, a Marshall with a 12AX7 in the phase inverter stage set to volume 5 will then reach the same volume with a 12AU7 set to volume 6 (perceived volume, not measured).

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 Voltage (Ug1): -2V (typical)
• Anode Current (Ia): 10mA (typical)
• Anode Power Dissipation: Maximum 2.5W per triode
• Anode Resistance (ra): 11kΩ
• Amplification Factor (μ): 60
• Transconductance (S): 5.5mA/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 either 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 operation.
• Coupling Capacitors: Capacitors with low capacitance (typically 0.1µF) are recommended to minimize high frequency disturbances.

EH 12AX7 / ECC83

• The 12AX7EH provides high gain with ultra low noise and detailed, musical tone that rivals the most desirable NOS types.

Files:

• Datasheet

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

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