The new DAC3.1x/II Balanced replaces the Canadian produced model MkI version and offers the following improvements and revisions,
- Better power supply now with valve regulation, ECL82, in addition to the valve rectifier also used in the DAC3.1x Balanced.
- Further simplified digital circuit and better PCB layout (it takes time to understand
- Improved digital – analogue I/V transformer interface
- No analogue filtering whatsoever.
- Improved line amplifier circuit, we have moved from the use of 2 x 6DJ8/ECC88 run in parallel to a series stage consisting of two ECC82s, this allowed the use of a better output transformer
- Better output transformer, 33:1 step down ratio, improving bandwidth, and dynamic signal transfer whilst also reducing hum and RF interference. The copper wired output transformers use the new IHiB core material in a double C-core configuration. Note the copper shrouds on the output transformers, a small detail perhaps, but an important one and not just cosmetically, commercially available transformer frames and shrouds are all made from steel, which is magnetic and when an air gapped transformer is assembled with a magnetic frame or shroud, its performance is adversely affected, because the air gap is shorted by the magnetic currents flowing in the frame or shroud and a loss of low level detail is evident. We therefore decided to move over to copper frames and shrouds, as they do not affect performance.
DAC3.1x/II Balanced “undressed” as it were showing the layout, with two mains transformers and the supply choke, rectifier/regulator PCB on the right and output transformer and digital and analogue PCB on the left.
Side view of DAC3.1x/II Balanced, brushed clear aluminium front panel.
Fully balanced input and outputs, ground post and single-ended input and outputs, note that being transformer coupled input to output still affords the transformer coupled low output impedance even when using the SE outputs.
The DAC3.1x/II Balanced is a Level Three product.