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AM-77 Dual-Mono Amplifier
180W Solid-State Power Buffer with unique error correction circuit
Ultra Transparent OptiLevel® Volume Control
OptiGain® Pure Class A all Valve Preamplifier
Block Diagram for AMR's AM-77: Pre-Main Amplifier

OptiGain® is AMR's unique amplification circuitry design: it is the combination of premium thermionic electron valves in the voltage gain stage with a patent-pending "Class X: Jikoda circuit" comprised of matched bipolar output devices.

AMR's "Class X: Jikoda circuit" in real-time, simultaneously detects and cancels unwanted artifacts in the audio signal: none pass to effect the playback of music.

The same cannot be said of traditional amplification designs found in mainstream amplifiers (of which the lion's share employ solid-state amplification) that use designs based upon the feedback circuit which in theory and in practice, is 'after the event' as it goes back and adjusts the circuit's input.

AMR through its exhaustive testing and auditioning, found that with generic feedback designs because errors in the audio signal still pass through, it is fundamentally flawed and largely accountable for the undesirable "solid-state signature" leveled at such sources. This is one of the main reasons why many have deemed the use of solid-state devices as an inferior approach to high-quality amplification when compared to the employment of valves.

As a result, with the AM-77, the resultant synergy of the OptiGain® circuit is the ability to amplify the delicate audio signal to an exemplary high level: whilst still retaining the sought-after finesse characteristically found only in the highest quality, "no feedback", single-ended valve amplification designs.

OptiGain® inherently outperforms all conventional types of volume controls to ensure that at low as well at high volumes, the dynamic range is virtually unhindered while preserving every bit of minuscule information in the signal. Also, incorporated is "Level Offset Matching" where different level input sources can be preset to the same level for the most enjoyable listening conditions.

OptiOperation® modes offer unrivalled functionality and flexibility. Whatever the requirements of the system, one or more AM-77s are more than capable of delivering what is needed at the optimum level of quality and can be seamlessly integrated into home theatre setups.

OptiProtect® protection circuitry reliably protects amplifier and speakers from conditions that might lead to damage without any sonic impact whatsoever when the protection circuitry is inactive.

OptiCool® offers exceptional cooling performance without the need for traditional resonant heatsinks which resonate as many tuning forks.


OptiPower® supply circuit is completely free of regulators from beginning to end. This is an essential pre-cursor for subsequent thermionic electron valve circuits operating with no negative feedback to attain the maximum sonic performance.

OptiMains® is truly one of a kind in that it will maintain the optimal voltage to internal circuits to ensure the best sonic performance (and longest tube life). This patent-pending circuit will automatically detect, monitor and adjust if necessary, the incoming voltage to ensure the correct voltage is always supplied to the relevant internal sub-sections.

OptiTrans®power supply transformers have been designed as advanced double C-Core types to sonically surpass even the impressive R-Core transformers used in many high-end components and comprehensively outclasses traditional EI and to roidal transformers used in many peer group products.

OptiSeal® is the galvanic sealing of functional sections in the transformer and includes the use of separate transformer windings to ensure that noise from one section does not contaminate adjacent sections in a full dual-mono audio circuit design.


OptiChassis® is based upon the "ratio aureum" design principle along with a pure copper inner chassis. The result is an unrivalled low resonance signature, optimised electrical and thermal properties.

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

AMR components use premium components chosen after extensive evaluation, lengthy and comprehensive listening tests. These include Ultra High Speed RF, military-grade design printed circuit boards, German-made premium film capacitors, AMR's own power supply polypropylene film Music Capacitors, low noise rectifiers and FEP Teflon insulated cable with silver-plate copper conductors for chassis wiring.

Information and specifications subject to change without notice.


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