STAX SRS-3100 is an entry level system from STAX, launched last year (2016). It is an earspeaker system consisting of STAX L300 electrostatic earspeaker + SRM252S earspeaker driver (amplifier). Although it is positioned as an entry-level system, from my experience, there is nothing of the sound quality that falls into that category. I had it for about a month, and I’m totally impressed by the sound quality!

I would to give a big thanks to Project Perfection Pte Ltd (Singapore) for the loan of STAX SRS-3100 electrostatic earspeaker system for reviewing purpose!

Web page:

http://www.staxusa.com/system/stax-srs-3100.html

http://www.stax.co.jp/produ/SRS3100.html

Before I go further with my subjective impressions, I would like to share my personal preference of sonic signature. Having a good audio community locally made me realize that many of us have a quite different personal preference of sonic signature. Therefore what I consider as an excellent sounding system might not suit others personal preferences. My sonic preference is pretty much influenced by my experience working with live setup in my church weekly, for many years. Besides that, we occasionally perform classical pieces with orchestra. So true to life performance has always been the foundation of my judgment in evaluating sound systems. Therefore I don’t use much of electronic music to evaluate a system. I listen to electronic music but don’t use them much when reviewing audio gears. I know it is still quite far for recorded music to be close enough to live performance, but at least that’s the objective or my reference for sound quality. 

Pros:

Excellent sound quality. 

Good value electrostatic earspeaker (headphone) system.

Cons:

Comfort, due to the shallow earpads.

Sound Quality

SRS-3100 tonality is balanced, very smooth, and leans a little toward warm signature. It has a minimum to almost no obvious coloration in its tonality, no perceived audible dips and peaks in the frequency response. There is some roll-off at the sub-bass, but the overall level of bass is good and satisfying enough for me. SRS-3100 is obviously not a bass head headphone, but it is also far from being a bass shy headphone. Level wise, the bass level is just nice, and I feel that the bass is more satisfying than Sennheiser HD800 and Beyerdynamic T1. Not that the bass level is higher, but probably due to the absence of treble emphasis, SRS-3100 bass sounds more balance with the midrange and treble. From memory, it has more bass than the famous Massdrop Sennheiser HD 6XX. SRS-3100 bass is not particularly fast and punchy, but I don’t consider it as loose or boomy either. Bass punch is good enough for most tracks that I tried, but might not be hard enough for bass lover. The SRS-3100 bass has a pretty good tonality and texture, complementing the average punch power. I always prefer a realistic level of bass and particularly dislike headphone with anemic bass. So far SRS-3100 bass didn’t disappoint. 

The midrange is probably the most addictive aspect of SRS-3100. Very natural sounding mids, smooth, expressive, detailed, full-bodied with good tonal density. Both male and female vocal rendered beautifully in a natural way. Vocal has good weight and body, in perfect balance with clarity and transparency. SRS-3100 always able to convey the emotion of the singer, and that is a very important aspect to musicality. Treble is silky smooth, very transparent, never sounded harsh or offensive. The first impression, treble might sounds a tad behind the midrange, but after careful listening, I think it sounds very coherent with the midrange and never stands out by itself. The treble level is just nice for me, I prefer smooth transparent treble that doesn’t show-off unnecessarily like the Sennheiser HD800 treble. I’m very impressed with the way SRS-3100 handles sibilant. Mids and treble sound transparent and clear, without any lacking of clarity in any way, but somehow sibilant tracks sound clear without being offensive. SRS-3100 could be one of the best examples of how to treat sibilant without sacrificing the treble quantity and extension.

Stereo imaging is quite clear, quite easy to pinpoint the location of each instrument, and center focus for vocal is good. Presentation wise it is more towards intimate presentation rather than the wide and spacious presentation. So holographic presentation is not as big and spacious as Sennheiser HD800, and more towards the intimate presentation of Kennerton Odin. I would say it is on the average level of width and depth.

For the big picture, if I have to group some of the headphones that I have or have experience with into a few group of sound signature, I would group them as the following:

Group 1: Natural with some emphasis on clarity & transparency (towards analytical):

Beyerdynamic T1

Focal Utopia

Hifiman HE-6

Hifiman HE-1000 v2

Sennheiser HD800

Group 2: Natural with a slight touch of warmness:

STAX SRS-3100

Kennerton Odin

Audio-Technica ATH-R70x

Massdrop Sennheiser HD 6XX

Group 3: Natural warm:

Audeze LCD-4

It doesn’t mean that headphones in the same group will have similar tonality, but they will have some similarities that when one's like a certain model in one of the group, there is a high probability that he/she will like the other models in the same group as well.

Generally, group 2 is the closest to my personal preference, and I also like some models in group 1 such as Focal Utopia and Hifiman HE-6. HD800 is a bit too analytical for me, and Hifiman HE-1000 v2 is a bit too polite in dynamic. Generally, when I listen to headphones in the group 2 I could relate them better with a live classical concert in a concert hall. Concert halls usually have some acoustic reverberation that gives some degree or warmness to the live performance.

STAX SRS-3100 is probably closer to the Kennerton Odin than the other headphones in group 2. What impressed me most is the perceived level of realistic sound reproduction, especially in the quality of micro-dynamic. It doesn’t really excel in the bass slam or brute force dynamic like the Abyss. But when listening to a classical orchestra, the timbre, detail, and micro dynamic are realistically impressive. SRS-3100 is not analytical, but when we listen carefully, it is actually very transparent in a realistic and natural way, without any hint of analytic character. Detail retrieval is very good without any exaggeration.

Build Quality and Comfort

Honestly, the build quality doesn’t impress me. Don’t get me wrong, it is not fragile, but the STAX L300 does feel plasticky and looks rather old-fashioned to me. I expect a more solid and luxurious feel for the asking price, but practically I didn’t have any issue with the build quality. Just personal preference end expectation. Although I know that electrostatic headphone need more wires than regular headphone, but I’m not a fan of the big flat cable. Again, just personal preference.

From the weight, the 12V adapter seems to be the linear power supply, not the switching mode power supply. Be careful when using other power supply, as the polarity is reversed, the positive is on the outside of the DC connector.

Comfort is a bit of an issue for me, the earpad of the L300 is too shallow for my ears. The inner side of the headphone touch my ears and it is not very comfortable for a very long session. But friends told me that the thin earpad problem can be solved by replacing it with the earpad from the L500 series. I haven’t tried it. Besides that I have no issue with the weight, to me, L300 feels pretty light. So from the comfort observation, the shallow earpad is my only complaint.

Summary

In summary, I really like and impressed by the sound quality of the STAX SRS-3100 system. I would rate it 5/5 stars for the sound quality. It might not be the best option for bass heavy tracks, but impressively very musical for classical, vocal, and audiophile tracks that I tried. In my opinion, the plastic build of the L300 is not really convincing for the price, and in my experience, the shallow earpad is not very comfortable for a long session. STAX SRS-3100 has the sound quality not to be overlooked despite its status as the entry level in the STAX system. I recommend anyone who is looking for a good sounding electrostatic system to try STAX SRS-3100. For the asking price, the STAX SRS-3100 offers a very impressive sound quality.