1. And Pure Quality; Using High-Quality for Original-Parts Not Only Guarantees And Quality And Long Service Life, But More Importantly, It Is A Strong That The Actual Performance Can Meet The Design Goals. 2. The Capacitor Adopts Audiophile-Grade With A Capacity Of 3300uf*4 And Adopts 2a And Above Rectifier To A Strong And Continuous Power Supply. The Resistor Is A Five-Ring Metal Resistor, And The Main Circuit Uses A Five-Ring Metal Film Resistor With An Accuracy Of 1%, Ensuring A Good Signal-To-Noise Ratio Of The Whole Machine. 3. The Pcb Uses 1.6mm Thick Double-Sided Sheets, 2.0 Oz Copper Thickness, And Full Tin Spraying Process To Good Passing Performance Of Large And Small Currents. Top- Pcb Quality. Using A Fully Enclosed Dust-Proof Potentiometer, The Performance Is More Stable And More Than Ordinary Potentiometers. 4. The Wiring Layout Of The Entire Circuit Board Is Quite Rigorous And Reasonable, And The Overall Pcb Wiring Adopts A One-Point Grounding . The Work Is Stable And Reliable, The Low Frequency Is Steady And Powerful, The Signal-To-Noise Ratio Is Excellent, And The Dynamic Range Is Wide 5. The Details Are Clear, The Transient Response Is Excellent, And It Can Play All Kinds Of Music With Ease, And It Performs Very Well In A Home Playback Environment. This Board Has A Treble And Midrange Pass-Through Switch Class A Parallel Regulated Regulated Power Supply Has The Characteristics Of High Speed, Low Noise And Low Internal Resistance. In Terms Of Noise, Music Detail And Sense Of Extension, It Is Unmatched By A Series Regulated Power Supply. The Performance Of The Series-Connected Regulated Power Supply For Dynamic Loads Is Not As Good As That Of Parallel Connection, Because The Conduction Degree Of The Regulating Tube Is Very Low WhenThe Series-Connected Power Supply Is No-Load, Which Is Similar To Class B. For Dynamic Loads, The Constant Current Source Of The Parallel-Connected Power Supply Must Be Accelerated From 0 To 60ma. A Large Current Is Sent To The Adjustment Tube. It Works A. For Dynamic Loads, It Only Needs To Accelerate From 30ma To 90ma. The Response Speeds Of The Two Are Definitely Different. Power Supply Voltage: AC12V-0-AC12V (Filter Capacitor Is 16v Withstand Voltage) Potentiometer From Left To Right: Treble Adjustment - Midrange Adjustment - Bass Adjustment - Master Volume Control Note:Different Batches May Have Differences In Product Appearance, Color, And Printed Characters, Which Will Not Affect The Use Colour:As Shown Material:PCB Size:About 140x66mm Package Contents: 1 * Tone Board Module 1 Set * Screw Mounting Accessor Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.