OTO Integrated Amplifier

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

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: -

Audio Note (UK) foil 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.