Acurus MUSE 16 Channel Preamp and M8 Power Amplifier Review
Tony O'Brien samples this esoteric 16-channel AV processor and power amplifier combination…
MUSE 16 Channel Preamp Processor
M8 8 Channel Power Amplifier
USD $7,999 / CAD $10,299 | USD $4,999 / CAD $5,899 respectively
After spending more than a few late-night listening sessions indulging in local brews, it seemed fitting to compare the Acurus MUSE and M8 AV processor and power amplifier combo to craft beer. It's an analogy that the CEO and part-owner of Indy Labs, Rick Santiago – being partial himself – won't mind one bit. Or should I say, 'one drop'?
You see, like craft beer, each Indy Labs' product is handcrafted, designed and built locally. It's a philosophy that goes down to circuit board level, which incidentally are designed and made in the US, with metalwork and final assembly completed in Indianapolis. Rick freely admits that his products aren't off-the-shelf solutions, but rather aimed at the high-end cinema market, specifically custom installations.
Above all else, though, he says his designs must sound amazing. The MUSE uses Burr Brown DACs, favoured by the Indy Labs team for their low noise floor, precise detail and neutral musical response. Meanwhile, the DSP module – now on its third generation – features a Texas Instruments chipset.
A sixteen-channel audio processor, the MUSE supports Dolby Atmos and DTS:X with native decoding of 15.1 Dolby Atmos and 11.1 DTS: X. We're told that both DTS:X Pro and IMAX will be added in the next 12 months, with an announcement due shortly. As such, it offers no less than 112 different speaker configurations, including up to three subwoofers.
Indy Labs understands that the MUSE is a substantial investment; therefore, it should have a much longer life cycle than mass-produced products. As such, the MUSE is built upon a modular platform, enabling both its HDMI and DSP (Digital Signal Processor) to be upgraded in the field by installers. More extensive upgrades, such as hardware chips and circuit boards, require the unit to be shipped back to the factory.
However, such upgrades will only be necessary in the case of major technological shifts, such as the transition to object-based surround formats, like Dolby Atmos. In the case of such an event, the warranty clock of the unit is reset. Most upgrades will, of course, be completed via firmware updates, with an update slated for release in the next three months adding HDMI 2.1 and eARC to the MUSE.
As it currently stands, the MUSE supports HDMI 2.0 (HDCP 2.2) and is HDMI 2.1 ready, which means it will support 4K UHD – specifically HDR10, HLG, and Dolby Vision. There's also a fourth-generation HDMI board in the works, adding 8K 60 fps and 8K fps. Indy Labs plan a 2023 release, but as is the case with many products now, supply chain issues will determine the final release date.
The MUSE offers manual calibration with five-point PEQ per channel and automated calibration in the form of ASPEQT. Developed entirely in-house, ASPEQT is Indy Labs' proprietary room EQ software. This comes in the form of a kit which is purchased separately, but it is assumed that professional installers will arrange calibration following installation. Of course, nothing is stopping those with the know-how from buying the kit themselves. The MUSE supports third-party control drivers for Control 4, Crestron, Elan, RTI, Savant, and URC, in addition to a remote control app.
We paired the MUSE with the company's M8 Power amplifier for the review, which boasts eight channels of amplification, rated at a whopping 200 watts (4-8 ohms) per channel with all channels driven. It features four-high performance Pascal Amplifier Modules, equipped with feedback circuitry that ensures the linearity of the M8 even at low signal levels.
Rick also tells me that the M8 is sonically comparable to the company's own highly regarded Class AB designs, with a natural yet detailed character. Naturally, as a Class D amplifier, it runs significantly cooler and has a smaller form factor than Class AB designs. It's also claimed to be incredibly efficient, quiet and free of audio distortion. As with the MUSE, the M8 will also work with the aforementioned control drivers and boasts the same five-year warranty.
While the MUSE and M8 lack nothing in terms of high-end ambition, what they do lack is size. It's the most striking aspect of the duo, sharing identical dimensions at an extremely rack-friendly 432x89x381mm (2 RU). It also means the MUSE and M8 will squeeze into spaces that wouldn't usually accommodate high-end gear.
Both units sport an anodised black satin finish. I know this isn't exactly new to the AV world, but they manage to pull it off with enough panache to separate the pair from mass-market offerings. The MUSE's good looks are helped in no small part by a 5-inch touchscreen on the centre of the processor and blue light that encompasses the aluminium power button. The touchscreen features a diagram showing the number of speakers connected, in addition to sound and video format and volume. Mercifully, for those with AV racks in the open, the touchscreen dims after a short while, but unfortunately, that's not the case with the light around the power buttons on the MUSE and M8.
Finished in contrasting white aluminium, the back of the MUSE has 12 balanced XLR inputs, while the auxiliary input (DB-9) provides an additional four balanced inputs via a TETRA cable (DB-9 to 4x balanced). It's an approach adopted by many expensive processors and also found in sister brand Aragon's Legacy Soundstage processors. Santiago explains that in addition to saving panel space, it's a solid, time-tested connection for those with larger speaker layouts.
The MUSE also has unbalanced gold-plated analogue stereo inputs, dual TOSLINK and coaxial digital inputs. Video connections consist of eight HDMI 2.0B inputs (2.1 ready) and two HDMI 2.0B outputs, the first of which is HDMI 2.1 ready. Like the MUSE, the M8 is somewhat unique in that fact that it offers Phoenix connectors for speaker connections. Relatively unknown in the audiophile community, these are the go-to in the install market for commercial and residential applications.
In addition to rack ears, the MUSE ships with a Logitech Universal Remote. I've yet to decide if this is a stroke of brilliance on the part of Indy Labs, or something of a cop-out. In all fairness, it's far beyond what many more expensive processors offer and in all likelihood, the installer will be using a third-party control system.
SETUP & CALIBRATION
Not only is the touchscreen attractive to look at, but it also offers the most user-friendly and easy-to-use GUI that I've encountered. With the M8 and speakers connected, it's then a simple matter of selecting which speaker to activate and designating size and crossover. It is simplicity at its best, and I read the user manual after the fact, more out of a sense of obligation! The web interface – accessed by typing the IP address into a browser – offers an identical no-nonsense, easy-to-follow GUI.
In addition to settings for speaker size, crossover, level and distance, there's a five-point PEQ for each speaker. Thanks to the local distributor, we borrowed the ASPEQT calibration kit for the review period. Interestingly, this features four numbered UMIK-1 microphones for measurement. Rick told me that this enables multiple microphones to receive the same signal at the same point in time.
The software is installed in a mini-computer, which is connected to the MUSE via HDMI. Up and running, it provides on-screen instructions and diagrams on how to complete the calibration. After manually setting levels and distances – a future update will enable distances to be automated – ASPEQT sets channel levels and applies PEQ, followed by phase. With the phase completed, ASPEQT rechecks PEQ and completes a final check of speaker levels before finishing.
It's an interesting process that took roughly twenty minutes to complete in a 5.1.2 system. Although there's an option to choose which curve to apply, a new set of measurements must be completed for each curve, and there's no way to store different calibrations onboard the MUSE. It's a first-world problem and something for the calibrator or installer to worry about rather than the client.
For the review, the M8 was connected to VAF Signature i91 front and centre speakers, with four VAF i90s used for rear surround and ceiling-mounted Atmos speakers. Two Definitive Technology Descend DN12 Subwoofers were used for the low-end, resulting in a 5.1.2 speaker configuration. Video sources consisted of Panasonic UB9000 4K Blu-ray player and Apple TV, connected to a Lumagen Radiance Pro, which in turn was connected to an Epson EH-LS1200 projector, shooting images onto a Severtson 100” Cinegray 16.9 screen.
Acurus AV's MUSE and M8 combo produces a large, airy and, above all else, natural soundstage. It gives soundtracks a sense of height and an often startling sense of width and depth. Detail retrieval is excellent, the duo producing dialogue that's not only extremely clear but realistic. But it's not only the finer sonic subtleties these two are versed in, as they're equally adept at whipping a storm with huge amounts of power.
With the excellent Prey on Disney+, the Dolby Atmos soundtrack provided an aural feast for the MUSE M8 combo. As the movie begins, the pair produced a vast, expansive soundstage. While I expect a piece of kit at this price level to be able to do this, what surprised me was the openness and natural quality of the acoustic. It doesn't intrude on the viewer but instead sounds thoroughly realistic without calling undue attention to itself.
Not only did the soundstage have an enormous sense of height, but it also gave my speakers a tremendous sense of width and depth, with sound wrapping around the room and seemingly emanating from behind the front speakers. Get up close to these, and there's a wonderful quietness, the MUSE and M8 producing not a hint of hiss or unwanted noise. It's from these depths that the two delivered effects with an excellent sense of placement and naturalness.
Dialogue benefits just as much, the airy quality and overall tonal character of this combo producing dialogue that is not only easy to hear but extremely convincing. So much so that I found myself going back to listen to Never Enough on the Dolby Atmos 4K Blu-ray of The Greatest Showman. In the hands of the MUSE and M8, it proved thoroughly captivating, leaving me nodding my head in disbelief at the duo's clarity. I can't recall hearing this rendered so clearly or naturally in my home theatre.
Arguably the best Batman movie since the Christopher Nolan trilogy, the 4K Blu-ray transfer of The Batman boasts an outstanding Dolby Atmos soundtrack. As the Batman enters Carmine Falcone's Club, the MUSE and M8 proved that they're not only versed in finer sonic nuances but more than capable of whipping up a sonic onslaught with barely a moment's notice. The sheer power that the little M8 produces belies its diminutive form, with enough volume to fill my room and then some. It's an exciting listen – one moment, it is producing the subtlest whispers with ease and conviction, and in the next, it's serving up the toughest of action sequences with power and authority.
During the car chase scene, I pushed the pair to levels that are probably not advisable for long-term listening. Nonetheless, they remained perfectly in control, without a hint of strain. Bass was powerful and clearly felt at the listening position, the MUSE making the Definitive Technology Descend Subwoofers earn their place.
Moving to the familiar Dolby Atmos soundtrack found on the 4K Blu-ray of John Wick, this combination delivered the best performance of this piece I've heard to date in my home theatre. Not only were dynamics served with speed and attack, but there was a wonderful sense of detail that I've not heard from the soundtrack before. As John makes his way toward the baths in the Red Circle, the sound of crickets can be clearly heard from outside.
Switching to the 4K Ultra HD Blu-ray of Top Gun, and the MUSE and M8 had a wonderful time with the eighties soundtrack. Once again, they surprised me with their musical prowess. They exhibited a wonderful tonal character that neither favours nor discriminates. There was a little more sparkle than I am used to hearing with my JBL Synthesis SDR-35, but it proved a welcome addition and was never overdone.
Acurus AV's MUSE and M8 combo are a little unorthodox to set up and calibrate. Yet as the old saying goes, the proof is in the pudding – and in this case, it's delicious. Not only is it capable of whipping up a sonic storm at a moment's notice, but it has a tonal purity that keeps you coming back for more. Overall, outstanding workmanship combined with exceptional sound quality means this dynamic duo must be on your audition list.
As the owner of ‘Clarity Audio & Video Calibration’, Tony is a certified ISF Calibrator with over a decade of experience. Tony is an accomplished Audio-Visual reviewer specialising in theatre and visual products.
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