Dac 4.4

Based on the ANK dac 4.1 kit and enhanced with ampsandosund transformers, circuit modifications and wiring expertise. 

Power supply starts with a M2PCB fitted with 6X5 rectifier and a 6MB8/ ECL82 tube as a regulated Power supply. Part choices are reworked for resistance to heat soak.

Our DAC strategy calls for a Resistor Ladder DAC architecture as opposed to the more common Delta-Sigma computer processing style DAC. Rather than using feedback loops and high frequency oversampling clocks. R-2R DAC turn on each required bit in the digital ‘word’ and the exact amount of current will flow from the chip to reconstruct the analog waveform. The method is perfect in its simplicity is closest to an analog sound.

The IVtransformers are proprietary to ampsandsoudnand tuned considering the total performance of the dac.  Delicate analog current signal that comes out of the AD1865 chip is run through a high quality resistors to create a voltage representing the audio signal – this signal is then transferred through a 1:1 ( I/V ) transformer which allows this ultra delicate signal to land on the line stage fully intact. Our approach doesn’t just chose the closest best choice based on a spec sheet but both measured performance and extensive listening tests to pic the final design that expresses our voice and yields max performance.

Once past the IV transformers the audio signal is amplified in the output tube stage which comprises of a 12au7 input tube and an ECC99 output stage.

The final part of the output stage is our custom output transformers. For those who know ampsandsound reputation for custom absolutist transformers, these outputs are no different. They are wound by the same team that winds outputs for our amps and places tone and performance above all else.  

Specs:

Output tubes: 12au7 / ecc99

Power Supply 6×5, ecl82

Line stage – Jupiter copper film

DAC Board CS8414 receiver , AD1865 analog conversion

IV transformers with nickel core laminations

Output transformers 200% oversized and wound with significant interleaving for extended frequency response.