Page 3 - Subjective Audio Analysis
Reviewing audio devices require extensively trained ears and lots of experience. Even for audiophiles, it may prove challenging at times to obtain an accurate evaluation of a product without a thoroughly familiar product to use as a simultaneous reference. While I am not going to even try to claim that I am the only trustworthy or best reviewer for sound, it is fact that most computer review sites have editors that are insufficiently trained in reviewing audio equipment. Give them practically anything and all you will read about goes along the line of "good bass, nice midrange, awesome treble, really clear sound, 10/10". While there are many knowledgeable audio reviewers at various respected online media outlets, these are by far the minority.
As I have mentioned in my past audio reviews, there are really no true objective measurements for speaker sound quality. As the reviewer, however, I will put it through a series of subjective tests to try to come up with the most objective rating possible (Yes, it's quite a paradox haha). The tests were conducted over Bluetooth 3.0 on my Apple iPhone 5 and Dell Venue 8 Pro. Since this is a digital transmission, the source hardware will not affect sound quality, so their results have been combined together. After over sufficient break-in time, we put the Adesso Xtream S2 to the tests. All tracks are FLAC or LAME encoded MP3s at 192kbps or higher.
Before we delve into our auditioning results, it is important to first acknowledge the physical limitations and market intentions of the Adesso Xtream S2. They are very compact, battery powered, wireless Bluetooth speakers that retails for about $40 at press time. Therefore, it is completely unfair to expect sound that will rival high performance desktop speakers -- they are simply not designed for that purpose. The purpose of the Adesso Xtream S2 is to allow you to rock some tunes a bit louder and a bit better than your phone or tablet's built in speakers, and snap off a few hands free phone calls occasionally while you are in your kitchen or living room. This does not necessarily prevent me from providing my honest opinion about the absolute results of these speakers, but keep the above in mind to establish a fair perspective. After all, audio quality matters, but so does the context.
To start off, the first thing I have noticed about the Adesso Xtream S2 is its significantly boosted midrange, especially in the upper portion, just underneath lower treble frequencies. It is someone expected for its size and packaging, because it is the easiest way to make your speakers sound louder and perceptibly clearer than it actually is, especially considering the enclosure size. As a result, vocals are quite clear, but artificial. The other downside is it gives a hollow effect, which is quite evident with the Xtream S2. However, for those who are looking for a set of external speakers that are good for making voice calls, these Bluetooth speakers' unbalanced characteristic actually rings a sweet spot for audibility. Just do not expect perfectly harmonized midrange for your songs.
Going down to the bass portion, Adesso employs what they call the "Double Bass Subwoofer Sound Technology". Other than these five words alone, there is no explanation of how it works. I am pretty sure it is just some sort of marketing term. For something that measures in at 17.7cm wide, 6.8cm tall, and 5.5cm deep, and drivers that are somewhat expected to produce a full range of sound, there is absolutely no way to produce bass to any significant extent. Bass production requires the movement of a lot of air with a lot of power. This is simply physics. You can quote me again in ten years, and we will still have the same problem. With a minimum frequency response of 80Hz, how much bass will you get? Well, as much as its size suggests -- not a lot. The bass is light, but present. For the little amount of bass that it has, it is reasonably round and defined, but it lacks tightness, immediacy, and articulation. Personally, I think Adesso has done a fine job balancing the enclosure and the drivers to produce bass; it is as much as you can reasonably expect from something of this caliber.
Treble, on the other hand, is not too hard to produce, even if space is limited. Even if you were to implement dedicated tweeters, they do not require a whole lot of space and power, and does not call for a ridiculous enclosure to produce remotely good sound. Of course, for forty bucks, I did not expect dedicated tweeters, and neither did Adesso. Upon listening to the Adesso Xtream S2, the first thing I realized was the treble tapers off significantly after the boosted midrange. It is recessed and quite attenuated, creating a fairly dark outcome. Generally speaking, treble is present in the background, but do not expect a whole lot. Interestingly, it is neither dry nor wet. Therefore, I would call it "damp" -- with a big asterisk. This is only if the original track has a clearly defined, single source of percussion instruments. If you listen to something where they go nuts with the drums, it will get real clashy, which is rather unfortunate.
Drawing from my commentary regarding its treble performance, I think we can easily derive its related characteristics. The Adesso Xtream S2 provides acceptable precision and detail for its size, given that the original track is not too complicated to begin with. Obviously, the designers can do better, but again, these are forty dollar wireless speakers. The issue is it lacks particular layering in parts of the midrange and pretty much all the treble, creating an overall effect that is not considered clean by most audio enthusiasts. The way I see it, it is not that bad -- I must highlight, for its price and size -- if songs have instruments that are widely separated across the range. But if there are multiple instruments in the same domain, it does get messy. Frequencies are just not so well separated. As far as sound cohesiveness is concerned, it is closely related to how harmonized the speakers sound. Since frequencies are not that well separated, it is "cohesive" in a sense that it is also a messy. Transitions between layers are okay, but this is mainly because the layering is not clearly defined in the first place.
How about its imaging characteristics? Well... it is hard to describe, because the Adesso Xtream S2 does not have much character to begin with. It is pretty much two dimensional. Heck, make it one dimensional. I will be honest here; it has a very narrow soundstage. Listen to this Bluetooth speaker with your eyes closed, and you will imagine something exactly the size it comes in. Everything sounds mashed together in the same place, like looking at the Rocky Mountains on a piece of paper, but this is because everything is, in fact, coming from the same place. To make sure I am not sending out the wrong message, for forty bucks and something of this size, I was simply not expecting miracles, and I did not get any, either.
Generally speaking, the Adesso Xtream S2 are not miracle speakers. They are pretty much everything I have expected, with absolutely no surprises. The sound response is somewhat unnatural, but the tuning is quite common for the package. Treble design can probably be better, but money is always a factor.
1. Introduction, Packaging, Specifications
2. Physical Look - Hardware
3. Subjective Audio Analysis