The DAC boards are worthy of comment in that they now run the PEtER spline filter algorithms used in the C1 DAC, updating their performance over the D1 dual-mono cards considerably. Both the DAC boards and the Sync IO board can be added to the D1.5 chassis at any point, without cost penalty, so you can upgrade or increase the capability of your unit as your system develops or demands.
One final difference that owners of the D1 will note is that the D1.5 is considerably lighter. That’s down to the aluminium base plate that replaces the steel one used in the D1. With the new, rigid aluminium structure of he transport, material continuity makes perfect sense and improves mechanical grounding.
Operationally, the D1.5 is identical to the D1, with all commands and menus accessible from the dual concentric knob/main display or the Control App. In addition, you get a small hand-held, IR remote for basic transport functions. In amongst the menus that allow you to change the display brightness or colour, or designate a specific display colour for a given format – say, orange for SACD, blue for CD and Green for MQA CD (yes, the D1.5 is MQA compatible) – there are two critical settings that you will need to select if using the unit as a transport:
The first is the clock setting, which needs to be selected between internal (if the unit is being used as a standalone player or as a transport without the Sync IO board fitted) and Sync BNC 75 OHM if the D1.5 is connected to a DAC with a clock output or an external clock. This clock setting is absolutely vital if you are going to get the best out of the D1.5, especially in the context of a DAC or external clock.
The second is concerned with CD and MQA replay. Step one of the MQA decoding process up-samples the raw 44.1 data to 88.2kHz/24bit (MQB). The D1.5 transport can be set to up-sample all CD material and output it at 88.2kHz, with MQA material passing through the MQA decoder, standard Red Book CD being up-sampled by the PEtER spline algorithms. This prevents on-the-fly sample-rate shifts and maximises sound quality for both formats. Operating status can be shown by user selectable screen colours. The examples above show a green MQA Studio (MQB) output, MQA output indicated by a yellow screen and MQA output indicated by a white screen. You can select each individual colour or have everything the same…
Listening in…
The single most important thing that you need to know about the D1.5 is that its performance as a one-box player has advanced by leaps and bounds – partly I suspect as a result of the improved transport (I never particularly liked the TEAC drives, always finding them somewhat mechanical and often sterile) and partly down to the improved DACs and mechanical grounding. Where the D1 tended to sound compressed and flat, the D1.5 is ouncy, bouncy, trouncy and full of fun, fun, fun… Well – not quite, but you get the point. More dynamic, more solid and more purposeful, with richer colours and greater dimensionality, the new player has all the musical intent that its predecessor so sorely lacked. The performance on SACD is particularly succinct and engaging, the higher res format generally delivering a more immediate and incisive presentation, underlining SACD’s continued relevance. Note weight on piano is far more explicit, as is the sense of string players bowing: nice details but their real importance lies in the greater sense of musical direction and coherence they reflect. Whatever the format, rhythmic nuance and phrasing, the overall shape of the piece, its structure and purpose are all significantly improved, putting the D1.5 on a par with the best and most musically expressive one-box players I’ve used. Add in the impressive SACD replay capability and the CH player has moved from also ran to serious consideration.
Stepping up…
The improvement is such that some people have questioned whether the D1.5 eclipses the performance of the C1 – given that it uses essentially the same decoding. Indeed, if the D1.5 really does render the C1 redundant, it calls into question CH Precision’s carefully constructed product line and expandable/upgradable ethos.