Industry Update

CH Precision Releases D1.5 SACD/CD Player/Transport

Christiaan Punter 4 November 2021 No Comments

Press Release November 3rd, 2021

The D1 CD/SACD player/transport was CH Precision’s first-ever product, a discrete multi-channel capable machine that established the Company’s now familiar, user-configurable, upgradable, card-cage construction. For over a decade, along with the C1 DAC, it has set the standard for high-resolution disc replay, even though, these days the focus for many listeners has switched to high-res streaming.

Yet, with the constant development of new production techniques, materials and even formats, optical disc has never sounded so good. The emergence of Glass CD, SHM discs, UHQCD, and new formats such as MQA-CD, has improved performance, giving disc replay a renewed relevance – while millions of existing discs still offer superb performance(s). But at the same time, the quality of replay hardware has diminished significantly, undermining those advances and masking their real value.

Time to revisit disc replay – Swiss style.

To match the improving digital standards we have developed our own, mechanically damped, high-mass MORSe transport mechanism. We have revised the optional on-board upsampling, updating it with our proprietary PEtER spline filter algorithm. We have added MQA replay capability, while also allowing users the choice of optimized MQA digital output when connected to an external, MQA capable DAC, avoiding on-the-fly sample-rate switching.

Meet the D1.5: same face; same precision engineering and flawless finish; same versatile, configurable, upgradable character; still the foundation stone of the CH digital eco-system – but now delivering a whole new level of performance! Owners could start with a single-box D1.5 player and grow it by stages and without cost penalty, all the way up to a nine-chassis, state-of-the-art digital front-end! Of course, they can also stop at two-boxes, three-boxes, or any number of boxes up to nine – the ultimate example of upgradability.

Features and Functionality

With an almost identical form-factor and operational interface (as its predecessor), the D1.5 continues the established CH aesthetic, fitting in perfectly with existing and future systems. However, internally it is a completely different machine, based around our own, all-new, proprietary transport mechanism.

That means that existing D1s cannot be physically upgraded to D1.5 status – but in keeping with CH Precision’s upgradable/future-proof ethos, a factory trade-in scheme and compatibility with all existing CH digital products ensures existing owners a cost-effective path to the substantially improved performance offered by the D1.5.

In-house designed and built Mechanically Optimized Reading System (MORSe) disc transport unit. See also the detailed information further below.
The optical pick-up and motor are precision mounted on a machined brass ‘sled that weighs almost 1kg, which is in turn isolated on a sophisticated alpha-gel suspension, fine-tuned to filter vibration down to AC Mains frequencies. This prevents vibrations generated by the spinning of the disc from reaching sensitive electronic boards, as well as low-frequency vibrations originating in the power supply or chassis disturbing the accurate tracking of the laser mechanism.
Massive, ultra-rigid support frame, constructed from almost 2kg of machined billet aluminum and directly coupled to the chassis base plate, with its improved four-point mechanical grounding and leveling system.
Fully compatible with SACD, CD, and MQA-CD discs.
CH Link HD, AES/EBU, S/PDIF, and TosLink digital outputs mounted as standard.
Optional dual-mono DACs and Sync IO board allow users to specify or adapt the unit for use as a transport or player, with or without external clocking.
On-board upsampling employs a state-of-the-art PEtER spline filter algorithm for CD replay.
Users can configure digital outputs to optimize replay of MQA-CDs with an MQA capable DAC, avoiding on-the-fly sample-rate switching.
Fully compatible with CH Precision’s C1 and C1 Mono DACs and the I1 integrated amplifier, as well as the T1 Time Reference master clock and X1 External Power Supply.

Detailed information pertaining to the transport mechanism

There have been online suggestions that the D1.5 uses a Marantz/Denon transport mechanism. Having contacted CH Precision I understand that, although some Marantz/Denon parts are used, the overall mechanism is very much a proprietary construction. Here is their response in full:

While the MORSe mechanism does use some Denon/Marantz parts, to suggest that it is based on a Denon/Marantz unit is definitely an overstatement. A Denon/Marantz mechanism is used as a donor unit, from which CH removes the Motor and Optical Pickup. All other mechanical parts of the reader mechanism are discarded. The motor and optical elements are then precisely installed into a precision machined brass mount, weighing almost 1kg. This mounting is then isolated on an alpha gel suspension. The high-mass results in lower fundamental resonance for the mechanism, as well as resisting the torque of the (variable speed) motor. The suspension also prevents vibration from the rotating parts reaching sensitive electronic circuitry.

The tray surface that carries the disc is the original part, but the guides (which control its motion) have been completely replaced. Its operation is far smoother and once the drawer closes it is now locked securely in place, with an additional damping element to prevent it from vibrating or being excited by the motor.

The motor control board has been completely replaced and the operation of the motor itself (especially in the loading phase) is now quite different from the original version.

A heavy machined bridge on top clamps the disc using a proprietary puck, entirely replacing the thin plastic parts of the original.

The transport mount and its suspension are in turn supported by a massive, milled aluminum frame (weighing a further 2kg) that is directly coupled to the D1.5 base-plate and its dedicated mechanical grounding system. This grounding arrangement uses the latest, composite, hardened aluminum/polymer spiked posts to provide superior energy transmission and the facility to precisely level the unit.

It is of course interesting to note that Denon knows a thing or two about producing direct-drive motors, having manufactured some particularly good direct-drive turntables in the past. Like those turntables, the secret of achieving optimum performance lies in the mounting arrangements used. The high mass of the laser mount/motor block demands increased mass and rigidity from the rest of the structure, to create a mechanical cascade to evacuate unwanted vibrational energy. CH Precision believes that it is only with this kind of clean-sheet approach to engineering that it is possible to produce the finest available disc transport – and the musical performance that goes with it.