Audiophilepure

http://www.hifiplus.com/articles/conrad-johnson-hva-1-headphone-amplifier/

“It’s a very ordered and beautiful sound, which might not bond it to those who equate bright and thin with ‘better’; this is a full, rich, and satisfying presentation and to many, it will be like trying good chocolate after years of cheap candy bars. That sense of naturalness comes across as an expansive, dynamic, and detailed sound that makes you listen deeper. Oddly, I found myself less bothered by itchy ear cups, as I sat in front of entire movements or whole opera acts. No, it doesn’t come with built-in anti-histamines; instead the HVA‑1’s performance is so musically honest, it takes you longer to reach your listening limits. But perhaps the biggest part to the c-j sound is that it just keeps on going. Your headphones sound as if this was where they always wanted to be, music seems to be an effortless element that you hear without any form of electronicky hash or harshness, and all’s right in the sonic world. The traditional audio world has its share of very expensive products that go for ultimate sound quality above the traditional roll-out of specifications, and now that happens in the personal audio world, too. Some will be infuriated by the sheer existence of this product, others will just hear it and buy it!”

https://www.audiophilia.com/reviews/2020/2/2/3xfichq6a178lp8sbb20pdg17wevgn

“HeadFi is a growing market in audio, especially among young people, as my generation is far less likely to own a home, or have the space for a big HiFi system compared with previous generations. If one wants to forgo the space and expense of a 2 channel system, the Arche could itself make a complete, satisfying system with the addition of a laptop and a nice pair of headphones. So, does that make it worth the $2,500 cost? I think that depends. If you already own the Utopia, Stellia, or Clear, this box can complete the sound these cans strive for, and there is a certain piece of mind knowing that one was designed to compliment the other in a world where headphone compatibility is a hotly debated topic. However, as a standalone unit, one can’t help wonder if there aren’t more competitively priced options that have most of these features, the $1,999 Naim DAC V1 comes to mind, as well as offerings from Schiit Audio that fall under 1k. There is also the issue of the amplifier mainly being for lower impedance cans, which while best for the vast majority of headphones, still means this isn’t a ‘one size fits all’ solution.”

https://audiofi.net/2020/03/xduoo-ta-03s-dac-headamp-like-a-creamy-mid-afternoon-coffee/

“As a pure DAC, it is resolving enough without having excessive flavour. Upon switching its analogue output to my Lovely Cube Premium class A solid-state headphone amp, it’s immediately apparent how average the DAC section on this unit is. The TA-03S resolves macro details well but micro details such as the scratch from calloused fingers rubbing against guitar string gets lost in translation and blends into the background. To that I say, who cares? You’re listening to music, not trying to count the number of people clapping in the front seat at the end of Track 3 of Adele’s Live at the Royal Albert Hall album.

As a pure headphone amp, the TA-03S does so many things right. I would even go as far as to say the performance is bottlenecked by the mediocre DAC stage. Mids are smooth and intimate with no hint of sibilance or graininess. Through the Gen 1 Chord Hugo, switching from my solid state amp to this unit expanded the soundstage abruptly.”

https://www.innerfidelity.com/content/quad-pa-one-headphone-amplifier-review

“The PA-One+ utilizes an two-channel ‘audiophile grade’ HyperStream ESS Sabre 9018K2M ‘Reference’ DAC chip capable of both asynchronous and synchronous 32-bit/384kHz PCM and DSD256 decoding. For this review I ran a Roon Nucleus+ into the PA-One+ with 16-bit/44.1kHz (FLAC rips) 24-bit/192kHz, DSD64/128 local-drive downloads and TIDAL and Qobuz streaming files. I did not tube roll the Quad as even though I have acquired (and continue to acquire) ever more tubes, they tend to input/line/phono applications, and I had no varietals of 6SL7/6SN7). I did not use it as a pre-amp either, rather, I focused on it’s headphone amp/DAC abilities. I used a variety of headphones, of varying impedances and sensitivity from the Audeze LCD-2 Classic, Mr. Speakers Aeon Closed, HIFIMAN HE1000se to Quad’s own Planar-Magnetic ERA-1, which had real synergy with the PA-One+ and that I settled on for all my critical-listening and review sessions.”

https://www.innerfidelity.com/content/manley-absolute-headphone-amplifier-review

Manley still weren’t satisfied with this however, as they also tossed in a set of Baxandall EQ filters and both Mono and Balance functionality. Anyone with hearing loss or old mono records will appreciate the balance controls, though they were more ‘nice to have’ than necessary for me. The EQ was the real star of this show however, and Manley’s pro-audio heritage shines here. Most hi-fi companies, when they implement EQ controls, design simple bell or shelf filters, boosting frequencies in a given area pretty equally. The Absolute uses Baxandall filters which have subtle tapering and shaping around the outermost affected frequencies, and combining both controls can give interesting effects, such as boosting or cutting the midrange – if you’re a tweaker this will give you hours of endless fun.

http://www.hifiplus.com/articles/monolith-by-monoprice-liquid-spark-headphone-amplifier-by-alex-cavalli/

The Liquid Spark uses a DC-coupled topology from the input to the output stage and is a fully discrete design. This approach eliminates the need for capacitors and op-amps in the signal path that might colour the overall sound. At the differential input stage the Liquid Spark uses laser-matched, low-noise audio JFETs instead of traditional bipolar transistors. JFETs are known to perform well in low-level applications, producing little noise while at the same time providing high input impedance. The output power stage employs high performance MOSFETs, which are ideal for designers looking to provide high power and very clean amplification within tight space constraints. The net result is a compact headphone amplifier that employs dual 18V filtered power supply rails that produces a convincing 1300mW RMS per channel into 50 ohms with very low distortion. With adjustable gain on the front panel, the Liquid Sparks exhibits a remarkable ability to produce a full sound that is crisp, quick, and sits quite comfortably in comparison with headphone amplifiers double or even triple its cost, as we will discuss shortly. “