The SwinSID Nano is one of many modern replacements for the failing original parts in a Commodore 64. If you have no sound from your C64, or if the sound isn't right (often parts of the chip fail, such as one voice or the filter) then you may need to replace your SID (sound interface device). Original parts are sought-after and therefore are now very expensive.
The SwinSID Nano b is Tolaemon's improvement on the SwinSID Nano. It's mostly indistinguishable from more expensive options (see my comparison video). It has the same footprint as the original chip, it has an LED on the underside (I use amber) and a startup chime.
The SID is usually socketed on the C64 board, so this should be a simple swop, but do check your board because if you have to desolder the original chip, replacement is a more involved process. I use socket-friendly pins.
Note that the SwinSID doesn't handle the analogue paddle input so that's a consideration if rotary paddles are important to you.
The SIDKick pico ("SKpico") is a drop-in replacement for the SID 6581/8580 sound chips in the Commodore 64 and 128 computers. It has been designed as an inexpensive alternative to other replacements while not making compromises regarding quality. It consists of a simple interface board and a Raspberry Pi Pico (or compatible clone). The emulation is based on an extended version of reSID 0.16, and includes a few additional features.
Emulates the 6581 or the 8580 in single or dual SID mode. Has a built-in configuration menu that is accessed with a BASIC command (SYS 54301 for the c64, SYS 54333 for the c128). Supports stereo output if you hook a DAC up.
Uses surface mount components so this is not a project for the inexperienced or the faint of heart.
An FPGA powered hardware platform for emulating the MOS 6581 and 8580 SID chips. It is a fully functional device that can be installed into a Commodore computer as a pin-compatible replacement.
The SwinSID is a pin-compatible and software-compatible replacement for the Commodore SID chip based upon an Atmega microcontroller. You can drop this chip right into a socket on the motherboard of a damaged Commodore computer, or you can probably drop it into a hardware synth that uses SID chips and hit the ground running. The firmware image and schematics are available for download for free on the website, so you can roll as many of your own as you want.
ODO has made available several hundred megabytes of Commodore-64 samples, stright from the SID chip.
An /*duino/i shield which emulates an MOS 6581... the SID chip.