@bruce_philly
How old is the DAC1 you are comparing to the Accuphase?
That DAC1 runs pretty hot. I think it might need a recap after 10 years possibly due to the internal heat causing aging of the caps. You should be comparing to the DAC3 these days. The DAC3 uses 512 delta sigma DACs over several ESS Sabre 9028 chips. Basically this design is a hybrid between a ladder R2R and a single delta sigma 1 bit DAC. This type Sabre chip is where performance minded DAC conversion is heading - the best of both worlds - high linearity (from 1 bit delta sigma) and low noise (of ladder style design) - achieving 9 bit resolution and extremely low noise a far cry from old single 1 bit sigma delta methods of the 90’s.
How old is the DAC1 you are comparing to the Accuphase?
That DAC1 runs pretty hot. I think it might need a recap after 10 years possibly due to the internal heat causing aging of the caps. You should be comparing to the DAC3 these days. The DAC3 uses 512 delta sigma DACs over several ESS Sabre 9028 chips. Basically this design is a hybrid between a ladder R2R and a single delta sigma 1 bit DAC. This type Sabre chip is where performance minded DAC conversion is heading - the best of both worlds - high linearity (from 1 bit delta sigma) and low noise (of ladder style design) - achieving 9 bit resolution and extremely low noise a far cry from old single 1 bit sigma delta methods of the 90’s.

