“The only real knock on the headphone output is the relatively high amount of background noise. There was a distinct transformer buzz that was quite audible when music wasn’t playing. It was easily drowned out by music, but still faintly noticeable if you were really, really zoned-in on it. If you don’t need the world’s blackest background this should be just fine, and I think the amplifier’s many positive traits definitely outweigh this negative, but some people demand absolute silence from their amplifier, and those folks would likely be a bit annoyed by this hum,”
“Sonically the Grace m9XX performed with flying colors when used as a DAC/pre. The well-controlled and extended bass that I heard through headphones was readily apparent when auditioned in a nearfield or room-based system. The m9XX’s unfatiguing upper-frequency presentation made listening through my all-solid-state and Class D amplification system a very natural and relaxed affair. My only quibble is that if you have built a system that is already soft and forgiving the m9XX might be too much of a good thing. However, if you want a neutral, revealing, but still listenable DAC, the m9XX checks all the right boxes.”
” Everything else is exemplary. Neither frequency dips nor rises mar any audible surface. There’s hardly any jitter; and even under harsh loads, IMD and THD rise imperceptibly. You won’t get 120dB out of this thing in any metric, but you will artefact-free 107dB, which is a hell of a lot better than 99% of amps out there.”
” As for sound quality, it leaves little to be desired, it has excellent tonal balance and exemplary bandwidth and detail. The low frequency extension and control is a must hear to believe proposition. While it does not veil or sweeten the mid range, neither does it add anything to it, meaning it has a musicality that makes even listening to headphones that fall out on the bright or harsh side can be a pleasant and eye opening experience. While I attribute a great deal of the performance of the DAC to the amplifier section, and the wonderful ears of the designers at Questyle, you would be hard pressed to find one that has greater detail and low frequency performance.
“For its five-hundred dollar asking price (US$399 if you don’t want the DAC or phono module), it’s unlikely there exists a headphone amplifier that can compete with the Jotunheim’s combined audible performance and feature set. The MK2 Soloist from Burson sells for US$499 but it isn’t modular or balanced. iFi Audio’s balanced iCan Pro isn’t far off two grand. We might journey to Audio-gd in China for their 8 watt NFB-1AMP muscle amp (US$450).”
” JDS Labs seem to be favoring a sleek build for the EL series, and I like it. The unit is made from anodized aluminum, and to correct what I said earlier, the anodizing process is actually handled across the river in St. Louis, so that is the one thing NOT handled in-house. Despite feeling pretty solid, the EL DAC is extremely light: 18oz to be exact. Simple and solid seems to be the order of the day.”
“Many manufacturers of solid state amplifiers claim to produce “tube like” sound, often doing horrible things to the tonal balance of their amplifiers while producing high levels of TIMD allowing their fans to hear things that aren’t actually in their music. The Wells Audio Milo is one of the few to actually attain the musicality of a tube amp, capturing all of that amazing micro detail that transcends from simple music listening to true music reproduction, without rolling off the high frequencies and boosting the mid bass to create a warmer sound.”
” There are both positives and negatives to this. The immediately obvious positive is that the full mono balanced configuration delivers four times the power that a single CMA800R would deliver in unbalanced mode. There is also individual channel control of left and right channels, while having two completely separate mono amplifiers guarantees complete channel separation.”