Audio T Verdict
The Audio Note M6 Phono is a Level 4 valve preamplifier combining a dedicated moving-magnet phono stage with a minimalist line-level signal path.
Its design includes separate left and right stepped attenuators, silver internal wiring, Audio Note copper foil signal capacitors and custom transformer-coupled balanced outputs.
This is a specialist preamplifier rather than an integrated amplifier. It must be partnered with a suitable power amplifier, and low-output moving-coil cartridges require an appropriately matched step-up transformer.
Audio Note M6 Phono Level 4 Valve Preamplifier
The Audio Note M6 Phono is a pure Class A, single-ended valve preamplifier with line-level inputs and a built-in moving-magnet phono stage.
It follows Audio Note's Level 4 design criteria, using zero negative feedback, valve rectification and selected proprietary components throughout the signal path and power supplies.
Its line stage uses ECC82 and 7044 valves, while the dedicated phono section uses three 5670 valves and has its own valve-regulated and valve-rectified power supply.
This Is the Standard M6 Phono
This product is the standard M6 Phono with conventional line-level inputs and a built-in moving-magnet phono stage.
It includes a balanced output circuit, but it does not include the balanced analogue CD input fitted to the separately specified M6 Phono Balanced CD Input model.
Confirm the required input and output connection arrangement when ordering, particularly when planning a fully balanced connection to a power amplifier.
A Preamplifier, Not an Integrated Amplifier
The M6 Phono selects sources, controls listening level and provides the voltage gain needed to drive a separate power amplifier.
It does not contain a loudspeaker power-amplifier section and cannot drive passive loudspeakers directly.
A complete system therefore requires suitable source components, the M6 Phono, one or more power amplifiers and a pair of loudspeakers.
What the M6 Phono Includes
- Valve line-level preamplifier
- Moving-magnet valve phono stage
- Source selection
- Separate left and right level controls
- Balanced output circuit
- Valve-rectified power supplies
What It Does Not Include
- Power amplification for passive loudspeakers
- Built-in DAC or digital inputs
- Network streaming or Bluetooth
- Direct low-output moving-coil cartridge input
- Balanced analogue CD input on this version
- Built-in headphone amplifier
Audio Note Level 4 Design
Audio Note classifies the M6 as a Level 4 component within its product hierarchy.
Its design follows the company's Level 4 criteria of pure Class A operation, zero negative feedback, single-ended circuit topology, valve rectification and carefully selected materials and components.
These principles are applied to both the circuit arrangement and the selection of wiring, resistors, capacitors, valves and transformers.
Pure Class A and Zero Negative Feedback
The M6 line stage operates in pure Class A and uses a single-ended circuit without an overall negative-feedback loop.
Audio Note uses this deliberately simple topology to minimise the number of stages and components through which the incoming signal must pass.
The preamplifier is designed around linear valve operation rather than relying on corrective feedback to reduce conventional distortion measurements.
ECC82 and 7044 Line Stage
The line-level amplification section uses one ECC82 and one 7044 valve.
The ECC82 and 7044 work within the M6's single-ended line-stage circuit before the signal reaches the custom output transformers.
The 7044 is used here as part of the current M6 design and should not be confused with the different valve complements found in some earlier or lower-level Audio Note preamplifiers.
Separate Left and Right Stepped Attenuators
Instead of combining a conventional stereo volume potentiometer with a separate balance control, the M6 uses one Audio Note stepped attenuator for each channel.
The two controls independently adjust the left and right listening levels. This allows channel balance to be set directly while avoiding a separate balance potentiometer in the signal path.
Both controls should normally be moved together once the desired left-to-right balance has been established.
Dedicated Moving-Magnet Valve Phono Stage
The built-in phono stage is designed for moving-magnet cartridges and presents a published 47kO input impedance.
It uses three 5670 valves, Audio Note copper foil signal capacitors and pure silver internal wiring.
The phono stage provides the gain and RIAA equalisation required to replay records through a compatible moving-magnet cartridge or step-up transformer combination.
Using a Moving-Magnet Cartridge
A suitable moving-magnet cartridge can connect directly to the M6 Phono's phono input.
The
Audio Note IQ III moving-magnet cartridge
is one potential partner within an Audio Note vinyl system.
Audio Note does not publish the M6 Phono's input capacitance or phono sensitivity in its current general specification. Cartridge output, loading and system gain should therefore be checked when planning the complete system.
Using a Moving-Coil Cartridge
The phono input is not a direct active moving-coil input. A low-output moving-coil cartridge requires a compatible step-up transformer before it reaches the M6's 47kO moving-magnet input.
For example, the
Audio Note IO I moving-coil cartridge
can be partnered with a correctly matched Audio Note step-up transformer.
The
Audio Note AN-S5/L
is designed for very low-impedance cartridges, but cartridge and transformer compatibility must always be confirmed before ordering.
Do Not Connect a Low-Output MC Cartridge Directly
A typical low-output moving-coil cartridge will not provide sufficient signal level when connected directly to the M6 Phono's moving-magnet input.
The step-up transformer's input impedance must be matched to the cartridge rather than selected solely by brand or output voltage.
Dedicated Phono-Stage Power Supply
The moving-magnet phono stage has its own dedicated valve-regulated and valve-rectified power supply.
This separates the phono section's supply requirements from those of the main line stage and reflects the extremely small signal levels produced by a phono cartridge.
Audio Note's main M6 power-supply design is based on the M10 Galahad supply and uses 6X5 valve rectification, together with valve regulation and stabilisation.
Silver Wiring and Audio Note Components
Silver internal signal wiring is used throughout the M6 Phono circuit.
The current specification also identifies one-watt Audio Note tantalum resistors, custom Audio Note electrolytic capacitors and Audio Note copper foil signal capacitors.
These components replace generic alternatives at critical points in the circuit and form an important part of the M6's Level 4 specification.
Custom UHiB C-Core Output Transformers
The M6 uses custom output transformers designed and manufactured by Audio Note in the UK.
Each transformer uses a UHiB C-core, with a copper primary winding and silver secondary winding.
The transformer-coupled output arrangement contributes to the M6's published output impedance of less than 10O and supports its balanced output circuit.
Balanced Output, Not Balanced Input
The standard M6 Phono includes a correctly implemented balanced output circuit for connection to a compatible balanced power amplifier.
This does not mean that the standard model has a balanced source input. Audio Note offers the M6 Phono Balanced CD Input as a separate configuration for customers requiring an analogue XLR source input.
The phrase “Balanced CD Input” refers to an analogue balanced connection. It is not a digital input and does not contain a DAC.
Connecting Line-Level Sources
CD players, tuners, streamers, DACs and other components with analogue line-level outputs can be connected to the appropriate line inputs.
The M6 does not contain digital-to-analogue conversion, so a digital-only transport requires an external DAC before connection.
The
Audio Note DAC 2.1x Signature
provides one possible route for connecting suitable digital sources to the M6's analogue line stage.
Matching a Power Amplifier
The M6's published output impedance of less than 10O makes it suitable for driving a wide range of compatible valve and solid-state power amplifiers.
Input sensitivity, input impedance, available system gain and connection type must still be considered when selecting the power amplifier.
Audio Note power-amplifier options include the
Ginrei monoblock power amplifiers
and
Conquest Silver Signature monoblock power amplifiers
.
The correct choice will depend on loudspeaker sensitivity, room size, preferred listening level and the input requirements of the selected amplifier.
System Gain and Input Sensitivity
Audio Note specifies a line input sensitivity of 126mV for a 1V output.
This figure should be considered alongside the output level of the source and the sensitivity of the power amplifier. An overly sensitive overall system can restrict useful adjustment to the lowest steps of the attenuators.
Audio T can check the complete gain structure when the M6 is being partnered with an existing source or power amplifier.
Dimensions, Weight and Chassis Arrangement
Audio Note publishes dimensions of 140mm high by 440mm wide by 410mm deep for the preamplifier.
Its shared M6 specification also lists the same dimensions for a power-supply chassis “if applicable” and gives a weight of 16kg for each unit.
Because this specification covers several M6 configurations, the reference to a power-supply chassis should not by itself be taken as confirmation that every M6 Phono order includes two separate chassis.
The exact current chassis arrangement, supplied accessories and space requirements should be confirmed when ordering.
Ventilation and Installation
The M6 should be positioned on a strong, level equipment support with adequate ventilation around the chassis.
Do not install it in a sealed cupboard or place another component directly over its ventilation openings. Allow additional space for cable plugs and safe access behind the unit.
Keep phono cables away from mains leads, power supplies and large transformers to reduce the possibility of hum entering the low-level cartridge signal.
Safe Power-Up and Shutdown
When starting the system, switch on source components first, followed by the M6 and then the power amplifier.
When shutting down, switch off the power amplifier first, followed by the M6 and the source components.
Reduce both level controls before switching sources, connecting cables or powering the system on or off.
Anodised Aluminium or Black Acrylic Fascia
Audio Note currently offers the M6 with a choice of anodised aluminium or black acrylic fascia.
The fascia choice is primarily visual and does not alter the published M6 Phono circuit specification.
Current production availability and build lead times should be confirmed when ordering.
M6 Phono Compared with the M3 Phono
The M6 Phono sits above the M3 within Audio Note's preamplifier hierarchy and meets the company's Level 4 rather than Level 3 criteria.
The M6 uses an ECC82 and 7044 line stage, silver internal wiring, one-watt tantalum resistors and UHiB C-core output transformers with copper primary and silver secondary windings.
The
Audio Note M3 Phono Balanced CD Input
remains an alternative where its particular Level 3 specification and balanced analogue source input are more appropriate.
M6 Phono Compared with the M6 RIAA
The M6 Phono is a complete source-selecting preamplifier with line inputs, level controls and a built-in moving-magnet phono stage.
The M6 RIAA is a dedicated standalone phono stage intended to feed a separate line-level preamplifier or integrated amplifier.
Customers requiring both line-source control and record playback should choose an M6 preamplifier configuration rather than assuming the M6 RIAA can replace a complete preamplifier.
Key Features
- Audio Note Level 4 valve preamplifier
- Built-in moving-magnet valve phono stage
- Pure Class A operation
- Zero negative feedback
- Single-ended line-stage circuit topology
- ECC82 and 7044 line-stage valves
- Three 5670 phono-stage valves
- Dedicated valve-regulated and valve-rectified phono power supply
- Main power supply based on the M10 Galahad design
- Separate Audio Note stepped attenuator for each channel
- Audio Note silver internal signal wiring
- One-watt Audio Note tantalum resistors
- Custom Audio Note electrolytic capacitors
- Audio Note copper foil signal capacitors
- Custom UHiB C-core output transformers
- Copper primary and silver secondary transformer windings
- Transformer-coupled balanced output circuit
- 47kO moving-magnet phono input
- Less than 10O published output impedance
- Anodised aluminium or black acrylic fascia
Frequently Asked Questions
Is the M6 Phono an integrated amplifier?
No. It is a preamplifier and requires a separate power amplifier to drive passive loudspeakers.
Does it have a built-in phono stage?
Yes. It contains a valve moving-magnet phono stage using three 5670 valves.
Can I connect a moving-magnet cartridge directly?
Yes, provided the cartridge is suitable for the M6's 47kO moving-magnet input.
Can I connect a low-output moving-coil cartridge directly?
No. A low-output moving-coil cartridge normally requires a correctly matched step-up transformer before connection to the moving-magnet input.
Does the standard M6 Phono have a balanced input?
No. The balanced analogue CD input belongs to the separately specified M6 Phono Balanced CD Input model.
Does it have balanced outputs?
Yes. Audio Note specifies a correctly designed and implemented balanced output circuit.
Is a balanced CD input digital?
No. Audio Note's Balanced CD Input is an analogue XLR connection for a source with balanced analogue outputs.
Does the M6 contain a DAC or streamer?
No. Digital sources require their own analogue outputs or a separate DAC before connection to the M6.
Why are there separate left and right level controls?
Each channel has its own stepped attenuator. Together they provide volume adjustment and allow accurate left-to-right level balancing without a separate balance potentiometer.
Does every M6 Phono have a separate power-supply chassis?
The shared specification gives dimensions for a PSU chassis “if applicable”, but it does not clearly identify the chassis arrangement supplied with every configuration. Confirm the current build when ordering.
Can the M6 drive active loudspeakers?
It may be connected to suitable active loudspeakers with compatible line-level inputs, subject to checking gain, connection type and input impedance.
Should a valve preamplifier be left switched on permanently?
No. Allow the M6 time to reach a stable operating temperature before critical listening, but switch it off when it will not be used to avoid unnecessary valve wear and power consumption.
What fascia finishes are available?
The current choices are anodised aluminium and black acrylic, subject to production availability.
Why Buy From Audio T?
- Experienced Audio Note system specialists
- Moving-magnet and moving-coil cartridge matching
- Step-up transformer impedance advice
- Source and power-amplifier compatibility checks
- Complete system-gain assessment
- Balanced and single-ended connection advice
- Valve-system installation and ventilation guidance
- In-store demonstrations through participating branches
- Ongoing system setup and servicing support
Contact your local Audio T store
to discuss the correct M6 configuration, cartridge matching and power-amplifier partnership for your system.
Audio Note does not publish the exact number of source inputs, phono-input sensitivity, phono-input capacitance or maximum power consumption in its current general M6 specification.