Project 9
Project 9 is a tone control project that uses Texas Instruments' LM1036 Dual DC Operated Tone/Volume/Balance integrated circuit. It is available in a 20-pin through-hole Plastic Dual-Inline-Package (PDIP) or Small Outline Integrated Circuit (SOIC) surface mounted package. The LM1036 is at its active lifecycle status that was originally released in the early 90’s by National Semiconductors and still going!
There’s plenty of LM1036 tone control PCA available online in assembled or kit form but only in 20-pin PDIP version. I did both chip package versions giving you more options to build. I made PCB layouts for 2 SOIC versions that use either 9mm or 16mm single linear potentiometers. The PDIP version uses 16mm single linear potentiometers. The Bill of Materials (Project9 LM1036) is the same for all versions. All provided for free, as is, no warranty.
Refer to Texas Instruments LM1036 spec sheet SNAS525C for more information. The spec sheet explains in detail how to change values of bass or treble capacitor (C16/C17, C14/C15) for different tone characteristic response curves. I have tried experimenting with different values but ends up using the values in the example application circuit, which in my opinion gives better response when mated with any of the power amplifier projects presented in this website.
I have redrawn the schematic diagram of the example application circuit to include U1, a 12-volt linear regulator in a TO92 package and D2, a LED of SMT-1206 package.
Project9 Schematic Diagram
Test results using QuantAsylum QA400 audio analyzer.
20-pin DIP version
20 pin DIP Bottom Copper Layer
20 pin DIP Silkscreen Layer
20-pin SOIC version with 9 mm only potentiometers
Bottom Copper Layer
Silkscreen Parts Placement Layer
20-pin SOIC version with 9 mm or 16 mm potentiometers
Silkscreen Parts Placement Layer
Bottom Copper Layer