发布时间 : 2015-12-23Class A Portable Amp With Class

  Pros: Stunning looks, high quality build and materials, power to burn, natural sound with strong mids.
  Cons: Gets quite warm on high gain, slightly bass-light and rolled-off treble, limited fine volume adjustment with IEMs.
Class A Portable Amp With Class
  Disclaimer
  I received a sample unit of the B1 portable amplifier from Aune Audio as part of a worldwide review tour. I was able to keep the unit for 10 days, during which I used it extensively. I did not have to pay for the unit; only for postage at the end of its tenure with me. The only expectation of tour participants was an unbiased review once we had given the B1 enough time for a fair evaluation. I am not affiliated with Aune in any way.
  About Me
  To begin, here's a little context. I'm 50 years old, and am pretty sure I have deficiencies in my hearing. In a recent, entirely non-scientific test I discovered I can't really hear anything over about 15 kHz, with roll-of starting around 12 or 13 kHz, which is actually pretty good for someone of my vintage. I also like to crank things more than the average bear to get the volumes I desire.
  I've been a music lover for decades, but am still relatively new to the MidFi/HiFi/Head-Fi game; I haven't listened to a lot of high-end equipment, and am not an expert on the technical aspects of electronics or musical terminology. I have read a lot of reviews and threads on Head-Fi, and spend a lot of time on the site; as such I know what has been helpful to me in reviews and endeavor to provide what I consider useful insight to help others make decisions about items they might want to try or buy, or avoid.
  I listen to a variety of music genres, in particular, Classical (mostly mid 1700s to mid/late 1800s), Jazz (late '50s to early 70's), Rock and some Prog-Rock ('70s), '80s New Wave/Electro, and Trip Hop/Acid Jazz (90's into 00's). My preferred sound signature would be characterized by a good sub-bass presence, tight mid bass, and relatively linear, detailed mids and highs. I like my music quite lush and rich, but with a good level of detail. I'm not a bass-head, am not a big fan of anything too boomy, and don't like highs that are too intense or harsh.
  Unboxing and First Impressions
  As usually happens when I receive a new piece of equipment, I was excited to get the Aune B1. The unit arrived by courier from Hong Kong, so first order of business was to get the protective packaging off. Thankfully, not a big job, and in a couple of minutes I had box and protective material removed.
Class A Portable Amp With Class
  The B1 comes packaged in a solidly constructed, textured black cardboard box. Even before lifting the lid, one has the impression of quality and pride in this product.
Class A Portable Amp With Class
Class A Portable Amp With Class
  Opening the box reveals two compartments within an intricately cut and folded corrugated cardboard inlay. In the large compartment one finds the B1 amplifier, within a thin, semi-opaque plastic sheath, and in the other, smaller compartment are the Micro USB charging cable and 20cm-long 3.5mm-to-3.5mm interconnect. Under the B1 there is a basic, folded instruction sheet, with Chinese information on one side and English on the other.
Class A Portable Amp With Class
  The B1 unit has a good heft to it. It has similar length and width dimensions to the Cayin C5 and Fiio E12A, but is a bit thicker (E12A = 14mm, C5= 15mm, B1 = 17mm). It is available in Black with black trim, or silver with red trim. I received a black B1.
Class A Portable Amp With Class
  The front of the B1 is gorgeous! Two glass windows reveal a circuit board with various chips and resistors. The effect is both hi-tech and artistic, and gives a highly unique feel. The only thing on the right side of the unit is the battery level indicator; press the button and a small light blinks: 5 times for full battery, 4 for 80%, 3 for 60%, 2 for 20% and 1 for 10%).
Class A Portable Amp With Class
  When the power is turned on, a small green light turns on in each window, giving off a tube-like glow. When ambient light is low, the glow from the B1 is quite mesmerizing and moody.
Class A Portable Amp With Class
  The back of the B1 is flat with nothing but the brand name and model number, and two strips of what looks like textured leather. The leather is slightly raised, providing a soft surface for resting the unit, or for mounting a DAP when stacking (the leather helps avoid scratching). The leather doesn't grip too well though, so a stacked DAP will tend to slip and slide unless using double bands to hold units together.
Class A Portable Amp With Class
  At the top of the unit you find the volume pot, and headphone-out and line-in jacks. The volume pot is metal, with ridges for grip, sits flush (not much to catch on things in a pocket) and feels tight and solid. Turning is not difficult, but it does offer good resistance to inadvertent adjustment while on the go.
Class A Portable Amp With Class
  On the left side you find the power control, Class A current adjuster (20MA or 40MA), and gain switch (low gain is +5dB, high gain is +15dB).
Class A Portable Amp With Class
  On the bottom is the Micro USB charging plug-in.
Class A Portable Amp With Class
Class A Portable Amp With Class
  The silver version of the B1 is quite attractive. The red leather back is quite striking in contrast to the silver aluminium chassis. Both colours of B1 are attractive and have a quality feel about them.
  Listening
  In my review I did some general listening using the Fiio X3ii as source, using a variety of over-ear headphones (Sennheiser HD650, Audio Technica ATH-R70x, and AKG K7XX). I also performed several comparisons to other portable headphone amps (Fiio X3 2nd generation's internal amp, Cayin C5 and Fiio E12A), using a variety of IEMs (Noble 6, T-Peos Altone 200, and Havi B3 Pro 1). Some of the equipment I used in my reviews was my own, and some was provided by 3rd parties for review purposes.
  General Listening
  Listening 1: Norah Jones – Come Away With Me
  ALAC > Fiio X3ii > Aune B1 > Sennheiser HD650 (Low Gain, Volume 6/10)
  The B1 is rated at 16-300 ohms, and the HD650 is a 300-ohm headphone. As such, one would naturally expect this combination to be at the limit of the B1's capabilities. At 6/10 and on low gain, volume was right where I like it (I like my Vs) and detail excellent.
  In "Come Away With Me," there is a lovely sound of brushed snare throughout that I find beautifully soothing; this was clear and textured. There is also a lovely, low-key guitar solo half-way through the song; this was atmospheric and high notes sparkled. Norah's voice was full, with her characteristic airy, textured tone. The B1 dealt with both song and headphone very well. Very enjoyable.
  Listening 2: Sade – Bullet Proof Soul (from Love Deluxe)
  ALAC > Fiio X3ii > Aune B1 > Audio Technica ATH-R70x (High Gain, Volume 6/10)
  The R70x is rated at 470 ohms. Of all the headphones I own, this was always going to be the ultimate test for the B1. Perhaps it was unfair to even attempt this one based on power ratings, but some manufacturers under-rate their amps so I figured I'd give it a try (as an example, the Fiio E12A is designed for IEMs and rated at 16-300 Ohms – same as the B1 – but it drives the R70x exceedingly well).
  If you've read any of my other reviews, you'll know that this is my favourite song for sub-bass, and I just love the combination of Sade's vocal with those of her back-up singers (depending on equipment, these backing vocals sometimes don't come through very well). The B1 dealt with all challenges very well. Volume reached more than satisfactory levels at 9/10 on low gain, and 6/10 on high (high gain sounded better; on low gain I felt there was just a touch of distortion). R70x test passed!
  My initial listen to this track was done on the low current setting. Curious about the Class A current adjustment (have never played with any Class A equipment before), I did a little reading and learned that with high powered phones or speakers, higher current beefs up bass and extends treble. Decided to give Sade a listen again on the high setting, and found this to be the case with the B1; the effect was subtle, but highs and lows had just a bit more authority.
  Listening 3: Duke Ellington & Johnny Hodges – Beale Street Blues (from Back To Back)
  ALAC > Fiio X3ii > Aune B1 > AKG K7XX (High Gain, Volume 5/10)
Class A Portable Amp With Class
  Even though only rated at 62 ohms, the K7XX is known to have low sensitivity and is notorious for being hard to drive and requiring amplification. This track is a lolloping blues number, with sultry sax, piercing trumpet, lively backing piano, and some fun, low-key guitar and drum riffs. The K7XX is beautifully driven by the B1. All instruments are presented clearly, with great texture, balance and detail. Stereo imaging and soundstage are excellent, with good space and instrumental placement. A very pleasant listen!
  After running the B1 on high gain for around an hour through the 3 general listening stages of this analysis, I noticed the B1 getting rather warm. I wouldn't say it was uncomfortably hot or anything, but it was warm enough that you might notice it in a pocket. Not a bad thing in winter, but perhaps not the greatest in summer.
  Comparisons
  Comparison 1: Beethoven – Cello Sonata No. 3 (played by Timora Rosler and Klara Würtz)
  320 kbps AAC > X3ii > Aune B1 > Noble 6 (Low Gain, Volume 2.5-3/10)
  320 kbps AAC > X3ii > Noble 6 (Low Gain, Volume 65/120)
  This is another favourite track for testing, with the interplay of rich tonality and range of the cello with energy and sparkle of the piano. The Noble 6 is a linear, neutral IEM, and I've found it doesn't pair particularly well with overly analytical sources.
  With the X3ii+B1 combination, this piece sounded marvellous. Sound was rich, with great body, richness and texture from the cello, and a lively, realistic tone from both left and right hands of the piano. Range on the volume pot was limited at a low volume setting of around 2.5-3/10, with little room for fine-tuning of volume.
  With the X3ii un-amped, I had more range to play with and much finer control over volume settings. That said, sound quality at equivalent volume was less satisfying than with the B1 combination. On it's own, the X3ii produced a less lively, less nuanced, more veiled performance. Cello was smoothed, and the piano was a bit one-dimensional. There were also touches of harshness in the treble that I could see being fatiguing in a more extended listening session.
  Comparison 2: Steely Dan – Gaucho (from Gaucho)
  ALAC > X3ii > Aune B1 > T-Peos Altone 200 (Low Gain, Volume 2.5/10)
  ALAC > X3ii > Fiio E12A > T-Peos Altone 200 (Low Gain, Bass Boost off, Volume 4.5/10)
Class A Portable Amp With Class
  Another favourite test track for atmospherics and micro detail, both vocal and instrumental. The Altone 200 is often described as bright (I don't find it overly so), and delivers good, strong bass.
  These two amps had quite different characters. E12A had great bass quality (sub and mid), along with excellent detail and texture in mids and highs. Texture and detail of snare drum, bass, guitar, and sax were excellent. Sound stage was open and had depth.
  B1 was more mid-forward, with more subdued bass and highs. Bass isn't as much rolled off as recessed, while there was some roll-off in trebles. Texture of main and backing vocals, and body of sax (though a bit smoothed), were more satisfying with the B1. That said, stage seemed a bit more constricted.
  While I enjoyed the music from both amps here, I found the E12A more extended in high and low frequencies, and B1 more mid forward. I liked the range in the volume pot for an with the E12A; this was again a bit limited with the B1, which I feel may be better suited to more demanding IEMs and cans.
  Comparison 3: Pearl Jam – Jeremy (from Ten)
  ALAC > X3ii > Aune B1 > Havi B3 Pro 1 (Low Gain, Volume 5/10)
  ALAC > X3ii > Cayin C5 > Havi B3 Pro 1 (Low Gain, Bass Boost off, Volume 4/10)
Class A Portable Amp With Class
  This is a great track for comparisons, especially of male vocals and energy. The dual-dynamic Havi has an almost cult following. It is known to have a wide open sound stage relative to other budget IEMs, with good texture and extension, especially in treble (some find the bass a bit on the dry side).
  The Cayin C5 sounded fantastic, with lovely tonality of bass, "school bell" and drums in the opening of the song. Eddy Vedder's vocal texture was clear and throaty, dry and rasping. Electric guitars were full of energy, clear, with no muddiness. High-end was a touch harsh and fatiguing. Space and good instrumental definition in performance, staging was open and wide.
  With the B1 bass was less prevalent, again with a more mid-forward presence. Gong sounds fuller than with C5. Vedder's vocal, guitars and drums were clean, warmer, smoother than the C5. High end less harsh, less fatiguing than from C5. Soundstage smaller.
  Conclusions
  There's a lot to like about the Aune B1. It drives powerful headphones with authority, and has a lovely mid-forward sound that is easy on the ears and suitable for long, fatigue-free listening sessions. Design is phenomenal, with great looks and a quality build and feel. If I had the power to improve anything about the B1, it would be 1) greater range on the pot for fine volume control, and 2) slightly more extension of bass and treble.
Class A Portable Amp With Class
  In comparisons with other popular portable amplifiers, I'd equate the B1 to the Sennheiser HD650 (contolled bass, mid-forward, clean, easy on the ears) and the Fiio E12A and Cayin C5 to the Audio Technica ATH-R70x (more natural extension of bass and treble). If you're an HD650 type, you will really like the sound signature of the B1. If you're more into the R70x, you'll still enjoy it, especially for longer listening sessions.