From auditions and electrical tests, AMR found most modern production valves were inconsistent in sonic terms and quality control/reliability was poor. In the AM-77 and CD-77, the majority of Valves are NOS.

These Valves were originally manufactured and selected from production for military and communication use. Large stocks accumulated throughout the Cold War remain to secure supplies for years to come.

AMR products come factory-fitted with New Old Stock Valves that have been selected to offer the highest sound quality. However, we appreciate that changing valves may change the sound.

Please be aware that doing so may void your warranty and may very well change the sound quality of your AMR product for the worse (please refer to the Warranty section for more details).

In the case of AMR products, when a part such as capacitor or resistor has been selected for a certain section, it had to pass very stringent trials and is most likely the best available choice disregarding cost.

Therefore, replacement of parts may very well change the sound quality of your AMR product for the worse. Please also be aware that doing so may void your warranty (please refer to the Warranty section for more details).

OptiIsolate® supports were drawn from the exacting aerospace industry to provide maximum mechanical isolation of the solid aluminum chassis from unwanted vibrations and resonances.

Therefore, your AMR component already offers superior resonance dissipation compared to peer products. However, different supports may slightly change the sound, feel free to experiment.

AMR strongly believes that its components should offer a superior sonic performance when only fed common mains electricity without the need for expensive after- market power conditioning products. Hence, AMR has integrated several unique technologies in its products to minimse the impact of mains quality.

AMR components incorporate critical electrical management designs - OptiMains®; OptiPower®; OptiReg®; OptiSeal® and OptiTrans® (please refer to the Advanced Design Features section for more details). The effect is that AMR components are minimally influenced by the constant variations in the quality of standard electrical power supply. Exotic power re-generation equipment may be of an added sonic benefit, but the increment is likely to be very limited.

After assembly, every AMR component is placed on a test bench where it is run continuously for 7 days or 168 hours. Measurements are taken all the while to ensure that it is operating within the intended parameters. However, AMR is aware that equipment tends to change in a more gradual fashion over the first 1,000 hours of operation.

At this stage, AMR chose CD over the competing new formats because most modern recordings regardless of their being issued as DVD-Audio, Super Audio CD® or CD have been manipulated so that they do not even start to approach the limits available from the CD format.

Many earlier recordings that have a wider dynamic range nevertheless, were engineered to fit within the capabilities of CD. Hence, at this stage, very little music material exists that takes advantage of the improvements offered by the new media standards. Therefore, AMR elected to provide a player that offers the recreation of music from the existing catalogue of recordings to the highest degree of realism.