Tone Board Preamp Pre-amp With Treble Bass Volume Adjustment Pre-amplifier Tone Controller For LM1875 LM3886 Amplifier Board

Product Specifications

Product name: FS-QA1
Supply voltage range: AC 15Vx2~AC 17Vx2
Frequency response: 20Hz~20kHz (+1dB through)
Bass adjustment range: +6dB
Treble adjustment range: +6dB
Signal-to-noise ratio: ≥90dB (A-weighted)
Distortion rate: ≤0.005% (20Hz≤f≤20kHz)
Separation: ≥60dB (1kHz)
Dimensions: 100mmx75mmx30mm (LxWxH with shielding plate)
Weight: 0.15kg (with shielding plate)

Design ideas

This pre-stage adopts the classic two-stage high-bass adjustment circuit to realize the personalized adjustment of high and low to suit everyone's different listening tastes. At the same time, a practical left and right speaker balance knob is added to meet the needs of most daily application scenarios. The audio channel adopts Weimar capacitors, which are characterized by extremely low loss, extremely fast speed, and natural balance of sound quality. The power filter capacitor adopts ELNA blue-pao audio special capacitor, which is characterized by low loss, thick bass, wide sound field, soft and sweet intermediate frequency, and slender high frequency. The op amp is based on the highly cost-effective 5532, with a gold-plated IC seat onboard, which is convenient for users to replace different op amps. The L-shaped wrapped shielding plate can greatly reduce the external induced noise, which is convenient for wooden or plexiglass chassis.

Reasonable layout

There are three basic elements that a good audio product must have: excellent wiring, reasonable layout, and sophisticated devices, all three are indispensable. For a reasonable layout, its signal direction must follow a single process, without redundant and complicated signal reciprocating links. The electrical signal is not born with the flexible thinking ability of turning, give it a simple and smooth road, it will obediently and diligently run from the starting point to the end point, and if it makes a corner in the middle, it is easy to find the north, like a Wild horses run wild. Once a reasonable layout is formed, the placement of components and the direction of lines will be natural and smooth, and performance and appearance will be perfectly unified.