MSB The Reference DAC

The MSB The Reference is built with a fanatic care for signal purity, from input to output. There are no buffers, current-to-voltage converters, or transistors in the signal path, and there are no active devices after conversion used at all. At the heart of it there are four Hybrid DACs, a current evolution of 20 years of MSB’s experience in building discrete DACs. The Hybrid DACs are individually shielded and fully balanced to the point of conversion that helps reject noise and maintain high resolution, and can operate up to 6Mhz for PCM, and up to 50MHz for DSD. The conversion is clocked by two

ultra-low jitter Femto 33 clocks. Before the audio playback starts, the DAC determines the base sample rate and selects the correct playback clock. MSB claims that “the vast majority of digital audio was recorded within two different frequency families: multiples of 44.1kHz and multiples of 48kHz. The 44.1kHz family includes CD, DSD and many hi-res formats such as 176.4kHz. The 48kHz family includes most sound recorded along with video and many hi-res formats, such as 96kHz and 192kHz audio. But there are differences between these two frequency families. One oscillator–such as 10Mhz or 27MHz–can be converted into the frequencies required to play back both the 44.1kHz and 48kHz families. However, the electrical circuits required are extremely lossy, leading to a large degradation of clock precision. The best solution is to have an independent clock oscillator for each frequency family chosen for each playback scenario”.  At the same time, MSB argues that external clocks are sub-optimal for digital audio because “A clock signal is a fast-moving precision electrical signal and is extremely sensitive to added noise or distortion. Each time it’s buffered or transmitted, a portion of its precision is lost. Even if a small amount of noise couples into the clocks, jitter will increase dramatically. A clock sent over an ultra-high quality cable will still increase its jitter considerably. The best solution is to create the lowest jitter clock as close to the DAC as possible”.

There are two very essential boxes attached to the DAC. The first is an external power supply (The Reference Powerbase) with separate digital and analog sides. The second addition is less visible as it is a smallish interface that is to be connected between a computer and the DAC. So called The Pro USB/Pro ISL solution is asynchronous electrical isolation between the source and the DAC. MSB asserts that removing the digital playback source from the room is the best one can do to eliminate another noise-generating component. The Pro ISL facilitates running up to 1km cable lengths between the USB module and the DAC. The only disadvantage is that you won’t be able to control the DAC from the computer. This does not represent a big problem, considering that MSB included lossless volume control in The Reference DAC.