Audio T Verdict
The Audio Note CD3.1x/II marks a substantial step up within the company’s range of integrated CD players, introducing the 18-bit AD1865 DAC and a more developed analogue output stage using two ECC88 valves.
It retains Audio Note’s deliberately focused approach to digital replay: a modified Philips mechanism, no oversampling, no conventional digital filtering and no collection of largely unrelated features.
This is a serious source component for someone with a valued CD collection and a sufficiently revealing system. It is considerably larger and more specialised than a conventional CD player, but its transport, DAC, valve stage and component selection have all been developed around the same purpose.
Audio Note CD3.1x/II Valve CD Player
The Audio Note CD3.1x/II is a Level 2 integrated CD player designed specifically for Red Book audio CD playback.
It is the first integrated model in Audio Note’s current range to use the Analogue Devices AD1865 digital-to-analogue converter, an 18-bit multi-bit DAC also employed in the company’s more advanced standalone digital converters.
The internal DAC feeds an analogue output stage built around two ECC88 dual-triode valves, Audio Note copper foil capacitors and tantalum resistors in critical areas of the circuit.
Designed for Red Book Audio CDs
The CD3.1x/II is a dedicated audio CD player rather than a universal disc machine. It does not play SACD, DVD or Blu-ray formats and does not provide streaming, Bluetooth or direct USB file playback.
Compatibility with recordable CDs can depend on the disc, recording method and condition. If CD-R playback is important, we recommend testing representative discs before purchase.
A Complete Audio Note Digital Source
The CD3.1x/II combines a dedicated CD transport, digital-to-analogue converter and valve analogue output stage within a single enclosure.
Its stereo analogue outputs can connect directly to a conventional amplifier line input, so an external DAC is not required.
Bringing these stages together also removes the need for a separate digital interconnect between the transport and DAC, allowing Audio Note to control the complete path from disc reading to analogue output.
Modified Philips CD Mechanism
The transport is based on a Philips front-loading CD mechanism modified in-house by Audio Note for dedicated Red Book playback.
It uses a three-beam optical pickup and a 780nm semiconductor laser to read the digital information stored on the disc.
The mechanism is housed within the CD3.1x/II’s substantial full-width enclosure and is operated using either the front-panel buttons or supplied remote control.
Analogue Devices AD1865 DAC
The CD3.1x/II is the first integrated CD player in Audio Note’s current range to use the Analogue Devices AD1865.
This is an 18-bit multi-bit digital-to-analogue converter rather than the TDA1543 used in the CD Zero, CD1.1x and CD2.1x/II.
Audio Note also uses the AD1865 within a number of its standalone DACs and has selected it on the basis of listening and circuit performance rather than the pursuit of the newest available converter technology.
The 18-Bit DAC Does Not Create High-Resolution CD Data
A conventional Red Book audio CD contains 16-bit, 44.1kHz data. The use of an 18-bit converter does not turn the recording into a high-resolution format or add musical information that was not stored on the disc.
The AD1865 is part of the player’s conversion architecture and was selected for the way Audio Note considers it to perform within the complete circuit.
No Oversampling
The CD3.1x/II does not mathematically increase the sampling rate of the CD signal before digital-to-analogue conversion.
Audio Note favours non-oversampling operation because it avoids generating intermediate samples that were not part of the original recording.
Non-oversampling is a fixed part of the player’s design rather than a selectable processing mode.
No Conventional Digital Filter
The digital circuit operates without a conventional digital reconstruction filter.
Audio Note’s intention is to reduce the amount of digital processing applied between reading the disc and converting its data into an analogue signal.
The CD3.1x/II therefore does not provide a menu of selectable filters, upsampling options or digital sound modes.
Dual ECC88 Valve Output Stage
Following digital conversion, the analogue signal passes through an output stage using two ECC88 dual-triode valves.
This represents a significant development over the miniature 6111WA valve stage found in the CD2.1x/II and gives the CD3.1x/II a more substantial valve-based analogue section.
Audio Note specifies a reference output of approximately 3.0V RMS, an output impedance below 2kO and channel balance within 0.5dB.
Audio Note Copper Foil Capacitors
Audio Note’s custom-designed and manufactured copper foil capacitors are used within the analogue output stage.
Coupling capacitors form part of the direct analogue signal path, making their construction and material particularly important within Audio Note’s component-led design approach.
The company manufactures these capacitors itself rather than relying entirely on standard off-the-shelf components.
Audio Note Tantalum Resistors
Audio Note tantalum resistors are used in critical areas of the CD3.1x/II’s circuitry.
These components form part of the wider progression from the lower models in the range, alongside the move to the AD1865 DAC and dual ECC88 output stage.
Exact internal components can change as Audio Note continues its development programme, so a current production specification should be confirmed if a particular component is important.
Connect Directly to Your Amplifier
The CD3.1x/II’s stereo RCA analogue outputs connect to a standard line-level input on an integrated amplifier or preamplifier.
Suitable inputs may be labelled CD, AUX, Tuner or Line. The player must not be connected to a moving-magnet or moving-coil phono input, as these are designed for the far lower signal level produced by a turntable cartridge.
Standard Connection
- CD3.1x/II analogue outputs
- Stereo RCA interconnect
- Amplifier CD, AUX or line input
- Amplifier connected to loudspeakers
Do Not Connect To
- Moving-magnet phono input
- Moving-coil phono input
- Speaker-level terminals
- USB-only digital inputs
- Headphones without a suitable amplifier
Front-Panel and Remote Operation
Front-panel controls provide access to the essential disc-loading and playback functions.
The supplied remote control adds convenient track selection, search, repeat, random play, time-display and programmed-playback functions.
The display can be dimmed or switched off to reduce distraction while listening.
Substantial Full-Width Construction
The CD3.1x/II is considerably larger than the CD Zero and CD2.1x/II, measuring approximately 445mm wide, 142mm high and 420mm deep.
Its 8kg weight and deeper enclosure reflect the more substantial internal construction, valve output stage and power-supply requirements.
Before ordering, check that the intended equipment rack provides enough depth for the player itself, its rear connections and sensible cable routing.
Check Your Equipment Rack
At 420mm deep before allowing additional space for plugs and cables, the CD3.1x/II may not fit comfortably on a shallow shelf.
The player also requires ventilation around its casework. It should not be enclosed in an unventilated cabinet or placed directly on top of another heat-producing component.
Black or Aluminium Finish
The Audio T product options currently include black and aluminium finishes.
The black version is normally supplied with a black acrylic fascia and gold-coloured controls, while the aluminium version uses an anodised aluminium fascia.
The internal specification remains the same for both versions. Current finish availability and expected supply time should be confirmed before ordering.
Placement and Ventilation
Place the CD3.1x/II on a stable, level equipment support with adequate ventilation and room for the rear connections.
Avoid direct sunlight, excessive dust, damp conditions and positioning close to a strong source of heat or vibration.
Analogue interconnects should be kept away from mains leads where practical, and the left and right channels should remain correctly connected throughout the system.
Initial Running-In Period
The performance of the CD3.1x/II may change during its initial period of use as its valves, capacitors and other internal components bed in.
It is worth allowing the player time to settle before making final decisions about system matching or cable changes.
Normal operation is sufficient. The player should not be left running unattended purely to accelerate the process.
Valve and Laser Servicing
The ECC88 valves, laser assembly and internal power-supply components are not user-serviceable. Do not remove the top cover or attempt to replace internal parts.
If the player develops a fault or struggles to read several clean, undamaged CDs, contact Audio T for advice and servicing support.
Looking After Your CD Collection
Dirty, scratched or damaged discs may cause skipping or prevent playback even when the player itself is operating correctly.
Handle CDs by their edges, keep the playing surface free from fingerprints and return each disc to its case after listening.
If a disc needs cleaning, wipe it gently from the centre towards the outer edge rather than following a circular path around its surface.
Key Features
- Audio Note Level 2 integrated CD player
- Dedicated Red Book audio CD playback
- In-house modified Philips CD mechanism
- Three-beam optical pickup
- Analogue Devices AD1865 18-bit multi-bit DAC
- First integrated Audio Note CD player to use the AD1865
- Non-oversampling digital conversion
- No conventional digital reconstruction filter
- Two ECC88 dual-triode valves
- Valve-based analogue output stage
- Audio Note copper foil capacitors
- Audio Note tantalum resistors in critical circuit positions
- Stereo RCA analogue outputs
- Approximate 3.0V RMS reference output
- Output impedance below 2kO
- Front-panel and remote operation
- Substantial full-width enclosure
- Black or aluminium fascia options
Frequently Asked Questions
Does the CD3.1x/II require a separate DAC?
No. It contains an AD1865 DAC and dual-ECC88 valve output stage, allowing it to connect directly to a normal amplifier line input.
What DAC does it use?
It uses the Analogue Devices AD1865, an 18-bit multi-bit converter also found in a number of Audio Note’s standalone DACs.
Does an 18-bit DAC make CDs high resolution?
No. A Red Book CD still contains 16-bit, 44.1kHz data. The 18-bit AD1865 is the converter Audio Note has selected to process that original signal.
What is the difference between the CD3.1x/II and CD2.1x/II?
The CD3.1x/II moves from the TDA1543 DAC to the AD1865 and uses a more substantial analogue output stage with two ECC88 valves. It is also housed in a larger and deeper enclosure.
Does it play SACDs?
No. It is designed for conventional Red Book audio CDs and does not decode the high-resolution SACD layer.
Will it play CD-R discs?
Compatible recordable discs may play, but performance can vary according to the disc, recorder, recording method and physical condition.
Does it support streaming or Bluetooth?
No. The CD3.1x/II is a dedicated CD player without network streaming, Wi-Fi or Bluetooth.
Can it play music through USB?
No. It does not provide a USB input or direct playback of stored music files.
Does it have digital inputs?
No. Its internal DAC is dedicated to the fitted CD mechanism and cannot be used with an external streamer, television or computer.
Which amplifier input should I use?
Connect the stereo analogue outputs to a normal CD, AUX, Tuner or other line-level input. Do not connect the player to a phono input.
Does it use valves?
Yes. Its analogue output stage uses two ECC88 dual-triode valves.
How large is the CD3.1x/II?
It measures approximately 445mm wide, 142mm high and 420mm deep. Additional space is required for ventilation and rear cable connections.
What finishes are available?
The Audio T product options currently include black acrylic and anodised aluminium fascias, subject to availability.
Why Buy From Audio T?
- Experienced Audio Note product specialists
- Advice on amplifier and system compatibility
- Help comparing Audio Note CD player models
- Equipment rack and ventilation guidance
- Suitable analogue interconnect recommendations
- In-store demonstrations through participating branches
- System installation and setup support
- Ongoing valve, laser and servicing assistance
Contact your local Audio T store
to discuss availability, arrange a demonstration or compare the Audio Note CD3.1x/II with other CD players.