Integrated Valve Amplifiers

OTO

The Audio Note (UK) OTO Integrated Amplifier is a Pure Class A, producing an outstanding level of performance.

Product details

The OTO is available in a variety of Push-Pull (Level 1) and Single Ended (Level 2) versions.

Push Pull

The OTO PP models have been specifically engineered for sonic performance rather than technical specification, and fulfil all Audio Note (UK) Level 1 criteria: –

• • Pure Class A Push-Pull Pentode operation
  • Materials and component quality

The output transformers are custom designed and manufactured by Audio Note (UK) and are of extremely high quality, offering outstanding, class leading performance in today’s world of high performance audio.

Single Ended

Part selection is optimised to realise the most neutral and realistic sonic reproduction.

The OTO SE models fulfil all Audio Note (UK) Level 2 criteria: –

• • Pure Class A Single Ended Pentode operation
  • Materials and component quality

Some of the superior quality components utilised in the OTO SE include: –

• • Aluminium foil, paper in oil capacitors, used in the most critical areas.
  • Dual power supplies and transformers, one for the output stage and one for the remaining circuitry.
  • Custom designed output transformers, manufactured by Audio Note (UK). These output transformers – one of the most critical areas of valve amplifier design – allow the OTO SE to produce impressively extended and controlled bass.

Some of the superior quality components utilised in the OTO SE Signature include: –

• • Audio Note (UK) Copper foil capacitors used in the most critical areas.
  • Audio Note (UK) Tantalum resistors used in the most critical areas.
  • Custom designed IHiB output transformers, manufactured by Audio Note (UK). These output transformers – one of the most critical areas of valve amplifier design – allow the OTO SE Signature to produce impressively extended and controlled bass.

Some of the superior quality components used in the OTO SE Silver Signature include: –

• • Audio Note (UK) Copper foil capacitors used in the most critical areas.
  • Audio Note (UK) 1 Watt Ni-Chrome resistors used in the most critical areas.
  • Audio Note (UK) KAISEI NP and KAISEI standard electrolytic capacitors.
  • SHiB copper / copper c-core output transformers, custom designed and manufactured in-house by Audio Note (UK). These output transformers – one of the most critical areas of valve amplifier design – allow the OTO SE Silver Signature to produce impressively extended and controlled bass.

Available finishes

• • ​Fascia – Anodised Aluminium or Black Acrylic

Current models

• • OTO Line PP
  • OTO Phono PP
  • OTO Line SE
  • OTO Line SE Signature
  • OTO Line SE Silver Signature
  • OTO Phono SE
  • OTO Phono SE Signature
  • OTO Phono SE Silver Signature

Technical Specifications

SORO

The Audio Note (UK) SORO Integrated Amplifier is a Pure Class A, producing an outstanding level of performance.

Product details

The SORO is available in a Push-Pull or Single Ended valve design.

Push Pull

It has been specifically engineered for sonic performance rather than technical specification, and fulfils all Audio Note (UK) Level 1 criteria: –

• • Pure Class A Push-Pull Pentode operation
  • Materials and component quality

A high gain power amplifier stage is used consisting of an ECC82 dual triode acting as an anode follower for the first stage, the output of which is applied to a second anode follower (ECC82) which feeds the parallel connected 6L6G output valves. This arrangement allows for a passive line stage / volume control circuit to be incorporated into the design.

The output transformers are custom designed and manufactured by Audio Note (UK), and are of the highest possible quality.

The power supply is a multi element design, ensuring precise operation of each circuit stage, whilst a DC supply feeds the low level valve filaments.

Single Ended

Part selection is optimised to realise the most neutral and realistic sonic reproduction.

Some of the superior quality components utilised in the SORO SE include: –

• • Aluminium foil, paper in oil capacitors, used in the most critical areas. Dual power supplies and transformers, one for the output stage and one for the remaining circuitry.
  • Custom designed output transformers, manufactured by Audio Note (UK). These output transformers – one of the most critical areas of valve amplifier design – allow the SORO SE to produce impressively extended and controlled bass.

Some of the superior quality components utilised in the SORO SE Signature include: –

• • Audio Note (UK) Copper foil capacitors used in the most critical areas.
  • Audio Note (UK) Tantalum resistors used in the most critical areas.
  • Custom designed IHiB output transformers, manufactured by Audio Note (UK). These output transformers – one of the most critical areas of valve amplifier design – allow the SORO Phono SE Signature to produce impressively extended and controlled bass.

The SORO SE fulfils all Audio Note (UK) Level 2 criteria: –

• • Pure Class A Single Ended Pentode operation
  • Materials and component quality

Current models

• • SORO Line PP
  • SORO Phono PP
  • SORO Line SE
  • SORO Line SE Signature
  • SORO Phono SE
  • SORO Phono SE Signature

Available finishes

• • Fascia – Anodised Aluminium or Black Acrylic

Technical Specifications

Cobra

The Cobra integrated valve amplifier produces 28 watts per channel from a pair of EL34 valves operating in Class A push-pull.

Product details

The Audio Note Cobra integrated amplifier is capable of driving a wide variety of ‘speakers thanks to its exceptional double C-core output transformers, which are custom designed and manufactured by Audio Note (UK).

Cobra is equipped with three analogue stereo inputs, and an additional three digital inputs, via the onboard DAC. The digital coax inputs can accept signals up to 24-bit/176.4kHz (native bit-depth for the Philips TDA1543 D/A converter chip is 16bit, so anything above this is truncated down).

The Optical SPDIF input can accept signals up to 24-bit/96kHz (see above). The USB input can accept up to 16-bit/48kHz.

Remote volume control, mute and input selection.

Technical Specifications

Meishu Tonmeister

An integrated amplifier that maintains the legendary Audio Note musicality, midrange magic and glorious tonal colour of the original MEISHU, whilst bringing new and previously unheard levels of information retrieval and dynamic expression, redefining what is usually expected of a 300B SET amplifier.

Product details

As with what we learned developing the 211 amplifiers, each element in a circuit is like each lens in a microscope, and has to be perfectly chosen and formed to correctly work with the proceeding and following lenses (or stages in the amplifier circuit).

If the lenses in a microscope are not correctly chosen and adjusted, the image becomes blurred, and detail and information is lost. The same is true for an amplifier circuit; if each stage is not absolutely correctly chosen and matched to work optimally with the rest of the amplifier, the result will be blurred, unfocused, uneven sound lacking in information.

So to create a better integrated amplifier, the natural idea was to simplify the circuit and optimise every element, so the combination works seamlessly and harmoniously together. This is exactly what we have done with the MEISHU Tonmeister.

The new PSU uses only one mains transformer, one 5U4 rectifier valve and one choke. When this arrangement is optimised, it works extremely well, producing a very homogeneous and ‘complete’ sound.

The input and driver stage is very similar to that found in the JINRO, TOMEI and ONGAKU, with a 12AU7 and 5687 driving an in-house designed and manufactured inter-stage transformer for the best energy transfer, evenness and authority. This is the most important, fundamental upgrade over the original design.

The output transformers for the new MEISHU were designed specifically for the project by Andy Grove, and it is not an overstatement to say that they are superb.

The circuit is now a beautiful example of elegant simplification, something that could only be realised thanks to our ability to create extremely closely matched transformers in-house, and having our own supply of custom resistors, in-house made foil capacitors and custom made electrolytic capacitors. These allow us to exert extremely tight control over the performance and voicing of the complete amplifier from input to output, something that is simply beyond the possibilities of manufacturers who have to rely on ‘off the shelf’ components.

Technical Specifications

Jinro

The Audio Note (UK) JINRO Integrated Amplifier is a Pure Class A Singled Ended valve amplifier that uses the highly regarded 211 triode valve, producing a level of performance that is radically superior to the vast majority of current designs.

Product details

It uses the same circuit design and topology as the legendary Audio Note (UK) ONGAKU integrated amplifier. However, where the ONGAKU uses silver wherever possible, such as for all transformer windings, the JINRO instead uses copper.

It has been specifically engineered for sonic performance rather than technical specification, and fulfils all Audio Note (UK) Level 3 criteria: –

• • Pure Class A operation
  • Zero Negative Feedback
  • Single Ended Output Stage
  • Valve Rectification
  • Directly Heated Triode operation
  • Materials and component quality

Available finishes

Top Plate – Anodised Aluminium or Black Anodised Aluminium

Technical Specifications

Tomei

The Audio Note (UK) TOMEI Integrated Amplifier is a Pure Class A Singled Ended valve amplifier that uses the highly regarded 211 triode valve, producing a level of performance that is radically superior to the vast majority of current designs.

Product details

Sharing the circuit design found in the legendary ONGAKU and JINRO integrated amplifiers, the TOMEI bridges the gap between them. Featuring a combination of both copper and silver for the transformers, its performance is both unique and beguiling.

Level 4 components are used throughout, including Audio Note (UK)™ Tantalum resistors and Foil Capacitors and in-house designed and manufactured copper/silver wired output transformers.

It has been specifically engineered for sonic performance rather than technical specification, and fulfils all Audio Note (UK) Level 4 criteria: –

• • Pure Class A operation
  • Zero Negative Feedback
  • Single Ended Output Stage
  • Valve Rectification
  • Directly Heated Triode operation
  • Materials and component quality

Available finishes

Top Plate – Anodised Aluminium or Black Anodised Aluminium

Technical Specifications

Ongaku

The ONGAKU Integrated Amplifier has rightly earned a place in history; its name is synonymous with the finest possible audio reproduction, and for once the reality is equal to the Legend!

Product details

It is a Pure Class A Singled Ended valve integrated amplifier that uses the highly regarded 211 / VT-4C triode valve, producing a level of performance that is radically superior to any other current designs.

Only the finest possible components have been employed: –

Audio Note (UK) silver wire has been use exclusively for all internal wiring, including all transformers and power supply connections.

Audio Note 2 watt Tantalum resistors have been used throughout.

All capacitors are either Black Gate Electrolytic or Audio Note (UK) silver foil.

All transformers are our own in-house custom designed and manufactured devices; driver and output transformers are fully silver wired AN-Perma 50 nickel C-core and the mains transformer is a fully silver wired HiB double C core.

No integrated amplifier has ever produced the levels of musical purity delivered by the ONGAKU… It is without doubt the finest possible integrated amplifier available today.

It has been specifically engineered for sonic performance rather than technical specification, and fulfils all Audio Note (UK) Level 5 criteria: –

• • Pure Class A operation
  • Zero Negative Feedback
  • Single Ended Output Stage
  • Valve Rectification
  • Directly Heated Triode operation
  • Materials and component quality

Available finishes

Top Plate – Anodised Aluminium or Black Anodised Aluminium

Technical Specifications