LS-77

Music + Heart = Love

LS-77

Music + Heart = Love

Make your heart soar.

Without speakers, music at home is nothing. And even if you own a standard set of speakers, chances are they won’t make your heart skip a beat when your favourite track reaches its peak.

With the LS-77, your music will soar – and so will your heart.

The tech spec.

The sleek look of the LS-77 is complemented with some stylish additions, including:

  • A Custom-made Isoplanner Tweeter
  • Teflon Signal Wiring
  • Copper Foil Inductors
  • Film Foil Capacitors

The artistry that goes into creating the LS-77 harks back to the attention to detail of old, and the superior sound it produces shows that all that hard work has paid off.

Feel everything.

With extraordinary Bass and Treble, combined with an elegant look and dynamic soundstage, the LS-77 speakers not only pack a musical punch but an emotional one too.

Music is vivacious, vibrant and real – making you feel you’re at a live event, and all the wonderful emotions that go with it.

Features

After 3 years of research and development, the LS-77 is based on AMR’s in-house developed Full Frequency Range Design (FFRD). FFRD truly extends the low frequency extension down to 26Hz and the treble response up to 40kHz, which is previously unimaginable in a 2-way bookshelf speaker design.

LS77’s front panel is sculptured from a 25mm (1”) thick aerospace grade Magnesium-Aluminium alloy billet, the rest of the cabinet use 10mm thick Magnesium-Aluminium alloy billets.

The LS-77 Magnesium-Aluminium alloy cabinet is 8 times stronger and hence cut the cabinet coloration by 8 times compare to the normal MDF cabinets. Further, the sound loss from the cabinet is 1000 times less. As a result, LS-77 delivers extraordinary clarity and transparency that is unprecedented.

The LS-77 employs a custom-made Isoplaner tweeter, which applies a force uniformly across the whole radiating surface and completely eliminates the breakup resonances found in all cone, dome or ring radiator drivers.

The Isoplaner tweeter also has a radiating surface equivalent to 5 x 28mm dome tweeters, which result in completely unrestricted dynamic levels with remarkably low distortion levels, even better than those of the best dome tweeters available.

The LS-77’s 10” driver has an exceptionally large radiating surface area. This together with its 28mm displacement provides a low-frequency output capability that is equivalent to six 6” HiFi low frequency drivers. Hence, the LS-77 can produce exceptional deep bass, incredibly clean and clear to a thunderous sound level.

The LS-77’s 10” driver uses a unique extra large 4″ voice coil, allowing the use of a cone structure with the rigidity and low weight of an excellent 5” or 6” bass/midrange driver. As a result, the LS-77 has the same speed, midrange clarity and articulation of an excellent small monitor.

The LS-77’s unique magnet system places the magnets inside the voice coil. This vastly reduces eddy current induced distortions and power compression. At rated input power, the LS-77 exhibits as much as 6dB less power compression when compared to conventional HiFi speakers, which means the LS-77 only requires 25W instead of 100W to drive to the same sound level as conventional high-end speakers during passages of music climax.

The OptiSlope is a unique and highly specifically crossover developed by AMR’s in-house filter calculation and optimisation software. Compared to 1st Order Filters commonly found in many high-end speakers, the OptiSlope cuts the interference between the drivers by 93%.

LS-77’s OptiPort design, made from solid Magnesium Aluminium alloy, completely eliminates the usual shortcomings of (i) traditional reflex port designs, which cannot be tuned sufficiently low to extend the bass response and (ii) transmission line designs, where the resonances of the transmission line structure will unavoidably muddle the upper bass frequencies.

For every speaker and crossover design, there will be a single spot in the listen room which the speaker sounds the best. In order to provide a much wider optimum listening area, both the LS-77’s high and low frequency can be fully adjusted from one extreme to another: close to walls vs. free field placement, small room vs. large lounge etc. Above and beyond the role.

The unique LS-77 OptiGuide is an unique design using curvilinear cast Magnesium Aluminium alloy waveguide. The OptiGuide equalises the difference between on and off axis response by mechanical means. It focuses all the sound across an identical radiation pattern for the widest range of frequencies and also matches up with the off-axis response of the low frequency driver. As a result, LS-77 may use its OptiSlope crossover to linearise the high frequency response for both on and off axis and reach a performance which before could only be achieved by dedicated super-tweeters.

Above and beyond the role of an exceptional quality midfield monitor, the AMR LS-77 was designed to form the main element of the AMR OptiArray® scalable, modular loudspeaker system. The AMR OptiArray® system provides a speaker system that can be expanded from a single pair, which is appropriate in terms of directivity and acoustic output for rooms up to around 30m2, while a dual-pair system will cover up to 60m2, finally up to 16 pairs in a “Focused Dual Line Array” configuration, which is capable of covering listening spaces the size of a small concert hall (480m2).

All premium components used were chosen after extensive evaluation, lengthy and comprehensive listening tests. These include all air-coil copper foil inductors, German metal foil crossover capacitors and FEP Teflon insulated cable with silver-plate conductors for all internal wiring.

Specifications

Sensitivity (2.83V/1m in room) 87 dB
Long Term Power Handling (AES/RMS) 150 watt
Peak Program Power Handling 600 watt
Impedance, nominal 8 ohm
Impedance, minimal 6 ohm
Frequency Response (in IEC Standard Room) 26Hz – 40kHz (+/-3dB)
Directivity Index (DI) 500-10KHz 6dB (+/-3dB)
Low Frequency Driver 24.3cm/10in diameter, 10cm/4in diameter voice coil
High Frequency Driver 12cm/5in long isoplanar ribbon
Crossover AMR OptiSlope® design (60 dB/octave)
Bass Enclosure Principle Transmission Line Port ®
Dimensions (each of a pair) 10in W by 19in H by 12in D,
25cm W by 49cm H by 31cm D
Weight Speaker (each) 77 lbs/ 35 kg
Shipped (pair) 255 lbs/ 116 kg

Reviews

HiFi+: LS-77 Review

AMR AM777 CD777

One of the most distinguished reviewers in the U.K. press, Mr Paul Messenger had some very complimentary things to say about the LS-77s: “Both the bass and treble extremes work very well, but the midband is the most important bit. Here the LS-77 demonstrates seamless transition from one driver to the other, exceptional overall coherence, and very superior stereo imaging, so much so that the steep slope filters used in the crossover seem to be entirely positive, while their inevitable complexity didn’t seem to be any impediment to the sound quality.”….”Though certainly costly, it’s also quite discreet and very elegant.

Good set-up flexibility and a fine ability to distinguish between the various components and accessories with which it is used suggests its Reference Class Professional Monitor tag is entirely appropriate.” We would like to formally thank Mr Messenger and HiFi+ for such an insightful and wonderful audition of the LS-77.

(Click name to read original review)

Stereo & Video: System of the Month

In the CIS’s Stereo & Video magazine, the AMR 77 System is awarded the system of the month award – with very nice compliments bestowed upon the AM-77 Pre-Main amplifier and LS-77 Professional Monitors.

(Click name to read original review)

April 2009 Dagogo USA – LS-77 Review

AMR was bowled over by the fabulous LS-77 review penned by Chris Redmond from Dagogo.

The reviewer hit the nail on the head when he commented that: “You really do have to forget about the whole floorstander/standmounter debate with the LS-77s and just consider them as full-range.”

This is the compliment that every reference class monitor design strives to attain.

For a more detailed review, please click on the following link:

(Click name to read original review)