Review – iBasso AM05
The AM05 takes a brand new design that looks quite different from the hybrid models IT03, IT04 and the more universal single dynamic IT01 and IT00. However, the AM05 seems to be combining some characteristics of the previous models, like the very custom-like shape of the IT03/IT04 in a little more compact form and better designed nozzle as the IT01/IT00. The shells are now made of acrylic resin that is supposed to be built using the inverted mold process. They look much thicker and more solid than the usual polymer hollow shells on the IT series. The transparent clear shell is also a radical change from the solid colors applied on all the previous models, and maintains a completely smooth finish. You can see all the components inside, drivers, crossover circuit and the silver thin tubes up to the nozzle.
The AM05 arrives in two faceplate colors, blue or green, which are still semi-translucent. ‘AM05’ is printed in silver color on the right side and ‘All Music’ on the left, but I think putting the iBasso logo would have been nicer.
The nozzle is made of stainless steel like on the IT01 and IT00 and follows the same removable threaded screens introduced on with the IT01s but more like the IT00 without rubber rings and much stronger attached. However, there are no spare screens included in the box. The nozzle is not straight as on the IT04 but also not as angled as on the IT01/00.
The very custom-like shape in addition to the long and well-shaped nozzle part provides a very ergonomic fit. The AM05 is certainly not as small as the IT00, but still not as large as the IT04 and fits much more comfortably. The fit is feel more natural, though still a bit tight. Being all BA drivers, there are no vents in the shells and so the isolation is quite good among universal-fit IEMs.
The cable is of silver-plated copper wire. The typical 4-strands tightly twisted. The quality is good with metal covers on the plug and y-split and slider. It is terminated in a straight 2.5mm balanced plug and includes an adapter for standard 3.5mm. The connectors are the usual MMCX types. They attach quite strongly to the earpieces sockets, though less tight as on the other iBasso models I tried. The plugs are a bit curved with red and blue markings for either side and have fixed preformed plastic guides attached.
Sources: iBasso DX220 & DX160, HiBy R3 Pro, Oriolus BA300s.
The AM05 is currently the only model from iBasso that uses all balanced armature Knowles drivers, five per side. The all BA configuration not just deviates from the dynamic and hybrid earphones of the ‘InTune’ series by their inner components and different outer design of shells, but mainly in the sound signature – and quite a wild change. All the IT models presented a warmer sound with strong, rich and impactful bass response, a good soundstage (for their corresponding price). The AM05, instead, goes into a totally different direction with a very neutral response from lows to mids and brighter, more revealing highs. It is clearly the most transparent and more focused into micro-detail, accuracy and clarity.
There is not much to say about the bass on the AM05. Despite the 5BA setup (not sure if a dual BA is used for lows or a single large BA), the bass is completely flat neutral. It is very tight and you can hear the definition of the lower notes, but there is not any ‘impact’ to feel. The extension is also limited with an early roll-off at the sub-bass, not very unusual for a multi-BA IEM. Fast but also short in decay, without much depth or weight.
The neutrality continues through the midrange. It is clean and very transparent. Very liquid, less forward and more lean at the lower mids, less suited for male vocals and missing weight on lower instruments. The clarity and precision is well heard through the whole midrange. Upper mids are more highlighted and revealing. There is a lot of energy for upper instruments and better texture for female vocals. Its emphasis continues through almost the whole treble as well, just missing some presence at the highest treble region.
The AM05 is definitely not a forgiving earphone when it gets to the upper midrange and treble response; while revealing and airy, the quantity can be too abundant and sibilance is certainly present at most tracks. Ear tips can be critical to tame down sibilance and harshness (at least to a certain degree). While some EQ can help on the bass response, it is more difficult to control the treble. Soundstage is about average – not narrow or a too intimate presentation, but definitely smaller when compared to the other iBasso IEMs. On the good side, the AM05 is very airy and rarely congested, and it is also very coherent being an all BA instead of hybrids.
As an extra, the AM05 paired with the Oriolus BA300s tube-amplifier shows excellent synergy. It is not about the power needed, but the tonality and fullness the BA300s adds to the AM05. The bass is much more present, more weighted with realistic impact and depth. The midrange gains more body and a richer texture. Highs are slightly smoother and more comfortable to listen to. Soundstage is larger and more open. The sound is more natural, and I could prefer this combination over the IT04 when portability is less important.
Being a hybrid IEM, the IT04 offers a much better and larger bass response. It has the extension, power, texture and dynamics. The AM05 is faster, tighter and very light. The midrange on the IT04 is well balanced, and even though it is little less forward it is fuller and richer. Treble is bright on the IT04 but not as on the AM05 and it is more forgiving.
Akoustyx R-210 (2 BA – Knowles TWFK)
Very similar sound signature between these two IEMs. Flat, very neutral to bright tuning, strong analytical capabilities, high speed, accuracy, and not forgiving upper midrange and treble. The AM05 has a very little touch of more weight on the lows and extension is a bit better (or rather, the R-210 rolls-off earlier). The R-210 offers a more even midrange from its low to upper region and it is little more forward and liquid. The AM05 is leaner on the low-mid and elevated on the upper-mids, less forward but a bit more textured and fuller. Highs are similarly bright and too energetic on both; the R-210 has a more ‘hot’ low-treble, but the AM05 can be sharper and more sibilant. None of these stand out in the soundstage.
final B3 (2 BA)
There is a very significant price jump of $200 to the B3, and it is not a technically ‘better’ sound quality than the AM05 and they sound quite different. The B3 is more midrange centered, forward, richer and much smoother and musical. It has a sweeter texture and performs great with vocals. The bass is fuller, warmer, even if it does not extend further than the AM05. The treble is full on the B3 too, but is still more relaxed and forgiving. AM05 is more revealing and very neutral, more detail focused.
To sum-up, among all the iBasso earphones, the AM05 has the best build quality and most ergonomic shape. It may not fit the smallest ears, but otherwise, is very comfortable with a good level of isolation. The sound quality and tuning is completely different than the usual iBasso house’ sound – very neutral with a bright treble, more focused into detail and accuracy instead of the warm and rich sound of the IT models.