Tube Bass/Treble Tone Control Preamp – Designed for Audiophiles and DIY EnthusiastsWe’ve designed this Tube Bass/Treble Tone Control Preamp with the audiophile and DIY enthusiast in mind. Featuring adjustable bass and treble controls, it allows you to fine-tune the sound to match your audio setup, delivering an ideal Hi-Fi listening experience.
Circuit Design:The circuit is inspired by the classic P.J. Baxandall Tube Tone Control Circuit** from the UK. This design uses frequency-negative feedback for low distortion but doesn’t rely solely on the feedback loop for tone control. Instead, it combines changes in the frequency characteristics of the coupling section with negative feedback to boost or attenuate bass and treble. The result is a wide control range and a flat response curve when both potentiometers are set to the middle position.
- Treble Control: The frequency response curve shifts along the frequency axis with minimal shape change.
- Bass Control: The frequency response curve remains more stable compared to most continuously adjustable circuits.
The Baxandall circuit is renowned for its exceptional sound quality and is widely used in professional stage audio equipment worldwide.
Why Tube Technology? Tubes offer unique advantages over solid-state or op-amp-based tone controls:
- High input impedance
- Wide dynamic range
- Low thermal noise
- Excellent transient response
- Low distortion
- Natural "air" and spacious sound
- Simple and elegant circuit design
Key Components: - Rectification: 6Z5P for high-voltage rectification
- Voltage Regulation: 6P1 tube for stable high-voltage output
- Amplification: Two 12AX7B tubes for signal amplification
Technical Specifications: - Tubes: 6Z5P x1, 6P1 x1, 12AX7B x2
- Overall Gain: 10dB
- Frequency Response: 15Hz–35kHz
- SNR: 80dB
- Harmonic Distortion: <3% (1kHz)
- Input Sensitivity: 1V
- Input Impedance: 100kΩ
- Output Impedance: 600Ω
- Power Supply: AC 100V, 110V, 120V, 220V, 230V, 240V (select one)
- Input/Output: 4 inputs with switching, 1 output
Important Notes: This preamp is designed to work exclusively with "pure power amplifiers" or "power amp stages". It is "not compatible"with AV receivers, integrated amps with tone controls, or preamp-equipped amplifiers. If you’re unsure, please contact us before purchasing.
