Sound impressions
When it comes to desktop gear, sound quality remains the ultimate measure of performance. Portable devices tend to add more usability niceties to the mix, like fancy UIs and intuitive navigation, but desktops are generally designed to deliver big performance without the fuss.
After several months spent casually and critically analysing playback performance across various genres of music, pairing the CMA Eighteen Master with different IEMs (and one headphone), and comparing it directly to its portable namesake, it’s time to take a closer look at how it performs in practice.
Tonality
While it’s difficult to describe the tonal character of amps and DACs in isolation, it’s still possible to get a sense of how much they colour the sound (or don’t, as is the case with CMA Eighteen Master). As such I’d describe the tone here as fairly neutral, quite transparent, and very accurate, with little to no colour anywhere along the spectrum.
Any emphasis I’m hearing is likely the result of the new Sabre DAC’s relative smoothness compared to previous iterations, which almost always had some sort of treble peak issues. The new ES9039PRO sheds much of this digital character in favour of a fuller sound, not necessarily warmer, but definitely more organic. In fact, this is probably the first Sabre-based device I’ve heard without the infamous Sabre ‘glare’.
Bass is often the foundation of an amplifier’s performance, and the CMA Eighteen Master impresses with its clean and controlled low end. The low frequencies never overwhelm or become bloated, which is a common issue with some amplifiers that prioritise bass at the cost of overall clarity. Instead, the CMA Eighteen Master provides a tight and articulate sub-bass and mid-bass response that complements the rest of the audio spectrum.
One track that tested the CMA Eighteen Master’s ability to handle deep bass was James Blake’s Limit to Your Love. The powerful sub-bass notes in this song have the potential to overwhelm lesser amplifiers, creating muddiness or bloating. Here, the low-frequency extension was extraordinary. It presented a full-bodied, textured bass response that didn’t distort or overpower the rest of the sound. Each bass note decayed naturally, with no excessive ringing or bloom, allowing for a more nuanced listening experience.
Another track, Angel by Massive Attack, highlights the CMA Eighteen Master’s ability to handle pulsating basslines with precision and authority. Where other amplifiers might struggle, making the bass sound sluggish or thick, the CMA Eighteen Master rendered the bass in this classic ‘basshead’ track with speed and nuance, but perhaps lacked just a smidge of punch. Still, each note was distinct, and the track’s deep beats felt both visceral and clean.
The percussive and electronic bass in Billie Eilish’s Bad Guy was also handled exceptionally well. Despite the deep electronic bass hits, the CMA Eighteen Master managed to deliver a satisfying-enough punch without letting the bass overshadow the vocals. The attack and decay of each bass hit were perfectly balanced, with no excessive warmth in the mid-bass region.
Midrange is where the CMA Eighteen Master truly stands out. Questyle’s Current Mode Amplification technology ensures that both instruments and vocals sound lifelike, clear, and well-separated. Many amplifiers introduce congestion or smearing in the midrange, but the CMA Eighteen Master avoids this, delivering an incredibly natural tonal balance.
Listening to Hotel California (Live) by the Eagles, the acoustic guitars showcased an organic warmth and resonant quality that brought out the true timbre of each string pluck. The CMA Eighteen Master kept the tonal balance true to life, avoiding any artificial brightness that can sometimes plague high-end amplifiers.
A standout track for showcasing vocal clarity was Bohemian Rhapsody by Queen. Freddie Mercury’s iconic voice remained full-bodied and crystal-clear, with a holographic sense of presence that made the track feel alive. The complex vocal layers were separated with ease, demonstrating the CMA Eighteen Master’s excellent resolution of even the most intricate mixes.
Adele’s Hello provided a perfect test for the CMA Eighteen Master’s handling of powerful vocals. The amplifier retained Adele’s voice’s intimacy and power, delivering every nuance clearly without any unnatural sharpness. On some amplifiers, this track can sound overly forward or congested, but with the CMA Eighteen Master, the vocals were rendered beautifully with full-bodied clarity.
Treble reproduction is crucial in high-end audio. Too much brightness can lead to listener fatigue, while insufficient treble can make music sound dull. The CMA Eighteen Master strikes a perfect balance in this area, providing treble that is both airy and extended without being harsh or fatiguing.
Listening to Take Five by The Dave Brubeck Quartet, the cymbals were reproduced with an airy sparkle, offering a subtle shimmer without any sharpness. The micro-details, such as the slight shimmer of a ride cymbal, were captured with stunning accuracy, allowing the track to retain its full tonal richness.
In Lorde’s Royals, the sharp percussive elements could easily have sounded brittle or overly bright on lesser equipment. However, the CMA Eighteen Master smoothed out any harshness while maintaining exceptional detail. The result was a listening experience that preserved the song’s crispness without introducing any unwanted brightness.
Mason Williams’ Classical Gas provided a further test of the CMA Eighteen Master’s high-frequency capabilities. The string harmonics were rendered with incredible clarity, and the high frequencies were presented without unnatural peaks or sibilance, showcasing the amplifier’s refined approach to treble.
Technical performance
Beyond frequency balance, the CMA Eighteen Master excels in delivering top-notch technical performance which, when coupled with IEMs that scale, illustrates why some prefer the physicality of desktop DACs and amplifiers over portable players. More space with more power means bigger components, better heat rejection, better shielding and, ultimately, a more effortless sound, all of which primarily bears fruit in the technical realm.
Soundstage and imaging
One of the most impressive aspects of the CMA Eighteen Master is its expansive soundstage. Listening to Baba O’Riley by The Who, the synth layers, drums, and guitars were distinctly positioned in space, creating a wide, deep stereo image that placed the listener at the heart of the performance. The soundstage felt alive, and the instrument separation was excellent.
The classical piece Clair de Lune by Debussy revealed the CMA Eighteen Master’s impressive imaging capabilities. The placement of the different sections of the orchestra was precise, with no sense of congestion or muddiness, even in the densest parts of the composition.
Resolution and detail retrieval
With its high-end DAC and amplification, the CMA Eighteen Master is capable of revealing minute details in recordings that other amplifiers might miss. Listening to Holocene by Bon Iver, subtle room echoes, vocal inflections, and delicate acoustic textures were all clearly audible, adding to the track’s emotional depth.
Dynamics and speed
The CMA Eighteen Master’s ability to handle fast transients and rapid tempo shifts is exceptional. A great example of this is Flight of the Bumblebee by Rimsky-Korsakov, where the amplifier showcased its ability to keep up with the frenetic pace of the composition. Each transient was sharp and precise, giving the piece an exhilarating sense of speed without any loss of clarity.
Overall, this is a mature sound, highly refined, and at least as technical as some of the most advanced portable players on the market – many of which cost even more than the Questyle, difficult as that is to believe. Since I’m usually more interested in performance with IEMs, and performance with convenience features like Bluetooth streaming, that’s what the next section will cover.
Continue to portable performance…
