Rega Isis Reference CD Player

The Isis is Rega's finest CD player — a reference-level component built to the highest standard the company has achieved, inside and out. At 19kg, with a custom solid anodised aluminium case, a genuine black chrome lid and front fascia, and a CNC-machined reference remote handset, it announces its intentions before a disc has been loaded. What is inside is equally serious: twin Burr Brown PCM1794 digital-to-analogue converters running in parallel dual mono configuration, discrete class A operational amplifiers and filters throughout, twenty separate power supply regulators, and two 50VA transformers providing complete galvanic isolation between the digital and analogue sections.

The Isis is for listeners who are committed to physical media at the reference level — who want the best that a dedicated CD player can offer, rather than a CD transport feeding an external DAC, and who want that in a component that matches the quality of the rest of a reference system.

Where the Isis Sits in the Rega Range

The Isis is the only CD player in the current Rega range stocked by Martin's Hi-Fi. It is positioned at the reference tier — priced and specified to partner the Osiris integrated amplifier or the Mercury and Solis separates system.

It connects to any amplifier with a line-level RCA or balanced XLR input. For those who want the balanced connection — and at this price point, it is worth using — the Isis's XLR outputs provide fully balanced analogue signal from the DAC outputs directly, not a balanced conversion of a single-ended signal. The USB input, separately powered and double-clocked to eliminate jitter, allows a computer or laptop to be used as a digital source through the Isis's analogue and DAC stages.

At the amplifier level, the Isis is correctly matched with the Aethos or above. At this level of source quality, the pre-amplifier and power stages should be capable of resolving what the Isis offers; the Brio and Elex are not wrong partners technically, but they are not where the Isis performs at its best.

Sound and Performance

The engineering of the Isis is aimed at a single outcome: that the digital-to-analogue conversion and analogue output stages contribute as little distortion and noise as possible, allowing the musical content of a CD to be presented with maximum fidelity.

The twin Burr Brown PCM1794 DACs, running in parallel dual mono mode, are the starting point. Parallel operation — two DAC chips per channel, combined — halves the noise floor compared to single-chip operation; the noise floors combine incoherently, so two chips at the same noise level produce a combined noise 3dB lower. Dual mono means each channel has its own completely separate DAC circuit with no shared components; there is no channel crosstalk at any point from DAC input to analogue output. The measured result is THD and noise below 0.0013% — among the lowest figures available from a CD player.

The discrete class A current-to-voltage amplifier that follows the DAC is the next step. Standard practice uses an integrated circuit operational amplifier for this stage; Rega instead builds a discrete circuit from selected components, operating in class A throughout. This stage converts the DAC's current output to the voltage that the rest of the analogue chain requires. Built discretely and running in class A, it adds less distortion and noise than an integrated circuit equivalent would.

The power supply architecture is remarkable. Twenty separate regulators — ten for the analogue circuits, ten for the digital — isolate each section from the others and from the mains supply. Two 50VA transformers, one dedicated to the analogue circuits and one to the digital, provide complete galvanic isolation: there is no shared magnetic or electrical coupling between the sections. K-Power smoothing capacitors — the same type used in the Osiris amplifier — provide the energy storage that sustains dynamics. The custom phase-lock loop (PLL) design in the digital section manages jitter reduction at the transport and re-clocking stages.

The Isis has a frequency response of 17Hz to 20kHz within ±0.1dB — not "–3dB at 20Hz" but genuinely flat from below audibility to the top of the audio band.

Build Quality and Design

The case is custom anodised aluminium, CNC-machined to the same standard as the Osiris amplifier case. The black chrome lid and front fascia are not lacquered or coated sheet metal; the chrome is genuine, applied to the aluminium. The 19kg weight is the honest consequence of a serious power supply — two 50VA transformers, a substantial capacitor bank, and a properly specified chassis — rather than added ballast.

The CNC reference remote handset is machined aluminium, consistent with the case finish. It is the same type of remote supplied with the Osiris amplifier, which is appropriate if the two are used as a system. Lifetime warranty against manufacturing defects applies.

Connectivity and System Matching

The Isis provides balanced XLR analogue outputs — fully balanced from the dual mono DAC outputs — and standard RCA analogue outputs. The USB input accepts digital audio from a computer or laptop with full isolation and double-clocking to manage jitter at the digital input stage. The analogue output level and output impedance should be confirmed via Martin's Hi-Fi if system matching with a specific pre-amplifier or integrated amplifier is a concern.

For a balanced connection to the amplifier, the Osiris's XLR input is the natural partner. For the Mercury and Solis system, the Mercury's line-level input receives the Isis's output. For those using the Aethos, the RCA input accepts the Isis directly; the Aethos does not have an XLR input.

At this level, the quality of the interconnect between the Isis and the amplifier is worth attention. Dave or Chris at Martin's can advise on cable matching at the reference level.

Technical Specifications

Who Is It For?

The Isis is for the listener at the reference level of the Rega range who wants to get the best from a CD collection — not as a secondary source feeding a streaming-first system, but as a primary, dedicated CD player matched in quality to a reference amplifier. It suits those running the Osiris, the Aethos, or the Mercury and Solis separates. It is the wrong choice for a system at Brio or Elex level — not because it will not work, but because the system will not resolve what the Isis offers. Those who want digital connectivity at a lower price point will find it built into the Brio MK7, Elex MK4, and Elicit MK5.

Buying from Martin's Hi-Fi

Martin's Hi-Fi has been in Norwich since 1968, and the Rega range has been part of what we do for years. We are still family-run — Elizabeth Gould runs the business today — and we stock only brands we have heard properly and stand behind.

The Isis is available to hear in our Norwich showroom; call ahead and Dave or Chris will set it up in a reference system so you can hear what the dual mono DAC architecture and discrete class A analogue stages actually deliver on your recordings. At this level of investment, a listening session before purchase is not optional — it is the whole point.

Reach them at dave@martinshifi.co.uk, chris@martinshifi.co.uk, info@martinshifi.co.uk, call on 01603 627010, or WhatsApp Dave or Chris directly on 07554 687137 for a quick answer after your purchase. You can read more about who we are and how we work on our Why Martin's page. We are at 85–91 Ber Street, Norwich, NR1 3EY, open six days a week.

Contact: info@martinshifi.co.uk | 01603 627010 | WhatsApp: 07554 687137 | 85–91 Ber Street, Norwich, NR1 3EY