The classic DCD-1650AZ, equipped with DENON's unique AL24 Processing for 24-bit processing and playback, is highly regarded for its sound quality, thanks to its combination with the high-quality 24-bit DAC (PCM1704) from Burr-Brown. It was awarded the grand prize in the CD player category of the 15th FMfan Dynamic Test Awards, selected by Mr. Tetsuo Nagaoka, known as the "God of Audio," surpassing even higher-end models. When purchasing a used DCD-1650AZ, there's one important thing to note: choose one with a serial number starting with 90, as shown in image 13. Those with serial numbers starting with 0, 1, or 91 and onwards use the OP262 op-amp from Analog Devices, which is known to fail quite frequently. The product for sale has a serial number starting with 90, so I've confirmed that the op-amp has been replaced with the improved Analog Devices AD8058 (photo 14) (which is reassuring). If the op-amp fails, the unit won't read discs even after replacing the pickup lens with a new one. Recently, there have been modified units that bypass the broken OP262 op-amp board, so please be careful. For this listing, I've replaced the pickup lens (which is still usable), replaced the rubber belt (a cause of repeated tray opening/closing), replaced the overcurrent protection elements, and replaced the rocker switch. There are cases where the DACs fail due to their own heat, resulting in no sound from either one or both channels when using analog connections, so I've attached heat sinks to both channels' DACs as a precaution (images 15 ⇒ 16). Also, I've removed the stickiness caused by the hydrolysis of the tray paint, which is common in this model, and repainted it, so there's no stickiness (image 6). In addition, I removed representative capacitors from the board and measured them with a multimeter, and there was no loss of capacitance. I've confirmed that CD playback is working fine for both channels via FIXED analog output and OPTICAL digital output. The remote control is also responsive. I've cleaned the PHONES jack to remove any crackling. Included accessories: * Generic power cord * Instruction manual (copy) * Replacement remote control RC-253 (new. Batteries not included). The volume buttons on the RC-255 are not usable. This is a used item of an older model, so it is not new. Please refrain from considering this if you are concerned about minor details.