Sound Impressions
Summary
The SR-L300 Limited tone is a vocal lover’s delight with a healthy bass fundamental. I had spent a lot of time comparing this to similarly priced electrostatic headphones from other brands and each one of them, including older STAX headphones, sounded a little flat or lacking in a bit of openness. Certainly, more than a few lacked the 3-dimensional presentation that the Limited can deliver with the right setup.
Granted, you have the guts of an “M-shaped” FR here with a pleasing mid-bass bump, a fairly forward 1-2k midrange, and a perky treble that still plays a slight second fiddle to that midrange bump without the presentation headroom suffering as a result.
Yet, even then, headphones such as the Koss ESP950 that follow a similar curve sound a little lifeless in comparison. So, it is not just the tuning then from the SR-L300 Limited that give it what I think is a natural-sounding and absorbing electrostatic signature, but also the technical competence of that L700 driver inside.
Simply put, this driver is very resolving with an excellent dynamic range performance. Instrumental notes are tight, clear and noticeably articulate yet at the same time lack any artificiality or dryness. The harmonic balance is excellent if slightly even-harmonic biased but personally I always think that’s how it should be to enjoy a headphone for long periods.
Staging
These types of M-curves have a natural tendency to push and pull at the soundstage with vocals to the fore and instrumental positioning to the side and slightly behind. However, I would content it is not a huge soundstage. Competing electrostatic headphones such as Hifiman’s Jade II paint a much grander soundstage and push you further back from the stage than the SR-L300 Limited’s more focused staging.
This is a soundstage with a strong sensation of vocal intimacy due to that 1-2k forwardness in the SR-L300 Limited tuning. Little quirks in vocal pitching from singer to singer are going to leap out at you much more, especially with stripped-down acoustical performance and breathy emo-like female vocals such as Ane Brun or Anette Askvik.
Despite instrumental positioning behind vocals they do not sound thin or lacking in weight. Unlike the Jade II, the SR-L300 Limited has a bit more mid-bass emphasis so it is a more forward and punchy sounding bass response. A response that adds some important timbral warmth and a good fundamental to instruments.
This is a type of staging I tend to personally prefer also so long as lower-pitched instruments get a healthy dose of mid-bass warmth and sound authoritative and not thin relative to the vocal. Indeed, the L300 Limited does manage to do that pretty well but just do not expect planar levels of sub-bass extension and presence.
Bass
Do not expect planar levels of low-end rumble and physically but do expect better than expected punch and body for an electrostatic headphone. In fact, outside of the VOCE and 007 MKII, I find the SR-L300 Limited bass response to be one of the better tunings out there. ON the FR there is a slight bump from around 80-100Hz and extends to about 200-250hz before it gently drops to the start of the lower mids.
Combine that with an excellent and speedy transient response from the SR-L300 Limited driver and you get a nice punchy and relatively full-bodied bass response. Lower-pitched instrumental work, in turn, benefit from the additional warmth and offer a decent bass fundamental which, whilst not delivering huge sub-bass power, sounds more planted with better extension than the likes of the ESP950 and Jade II.
What works particularly well for me is the level of control and separation in the SR-L300 Limited’s low-end performance. The layering is top-notch with excellent levels of detail being allowed to shine through.
Mids
A more intimate and vivid experience than some competing electrostatic headphones. That little dip in the lower mids is complemented by a long and steady rise to a peak around 1-2k with the net effect of a very forward and vivid vocal presence for both male and especially female vocals. Instrumental positioning is behind vocals but they do not sound thin and lacking in presence.
The additional treble bumps around 5-6k and 8-10k with good energy beyond also means those intimate vocals are not dulled down and lacking in headroom to breathe. The lack of treble bias or an overly forward treble curve also means instrumental timbre has a very natural harmonic balance.
To be honest I would class the midrange timbre as pleasingly wet in tone despite its excellent clarity. You will be hard-pressed to push out any sibilance with the SR-L300 Limited if it is not already there in the recording.
There does seem to be a slight 2-4k dip before that rise from the upper mids into the lower treble but nothing unusual for me or overly suck-out. Just enough to prevent percussion timbre from coming across as bright or distracting.
Treble
There is some definite treble elevation around 5-6k and 8-10k on the SR-L300 Limited but it is not terribly elevated to the point where it tips the balance.
The amount of headroom is very good also and it does not seem like it fades or rolls off with plenty of air and separation. Compared to the Jade II’s energetic tall treble it might sound a bit more relaxed, wetter but definitely delivering a bit more body.
That, in turn, helps with lower-pitched instrumental timbre which never seems to suffer from harsh or bright partial overtones. Percussion never sounds splashy or sibilant on the Sr-L300 Limited. The SR-L300 Limited strikes a really nice balance between clean and articulate, smooth and balanced with that effortless electrostatic delivery and smooth.
Synergy
Efficiency
Surprisingly, I found the SR-L300 Limited to be one of my most sensitive electrostatic headphones when an A/B was done from the Jade II amp’s dual 5-pin pro bias output from a single source.
The current demand was more for the likes of the Jade II, ESP950, and even the smaller more portable Kingsound HS-04. My older SR-303 did seem more in line sensitivity-wise with the SR-L300 Limited but lacked the same pop and dynamic range of the new driver.
Synergy
That is good news if you are using the STAX SRM-D10 portable DAC/Amp, a unit that I find lacks a bit of headroom with more demanding electrostatic headphones such as the VOCE but delivered more than enough power and current for the SR-L300 Limited.
The synergy is quite neutral, however. the SR-L300 Limited still sounds quite punchy but that holographic soundstage becomes a little flatter for me and some of that timbral sweetness you get from high-end tube energizers is swapped in favor of a drier cleaner sound.
With higher-powered tube energizer amps such as my modded dual 6SN7EH tube-driven T1, the dynamic range gets a huge boost over the drier and slightly leaner Jade II amp. That tube flavor shines through also with a richer instrumental and vocal timbre which I much prefer.
There is also a ton of headroom with this amp and a superb black background which just serves to emphasize the excellent instrumental separation and placement performance of the SR-L300 Limited.
Personally, I would elect to go with a tube-based energizer amp with the SR-L300 Limited. I enjoy the timbral richness and slightly wetter tone more than some of the drier solid-state options out there. Of course, this is personal preference but a little warmth goes a long way in my opinion to turning the SR-L300 a long-term listening performer.
Select Comparisons
Hifiman Jade II
$1399
Technical
The focus here is on the headphone rather than the entire Jade II system which includes the amp. The headphone alone is $1399 so a fair bit higher in price than the SR-L300 Limited. In fact, it is just above the SR-L700 MK2 in terms of pricing.
The Jade II has a substantially larger driver packed into a form factor derived from their Ananda and HE1000 series planar headphones. So, instead of rectangular its more of an oval ear cup. Similar cup height but wider and more ergonomically shaped to fit around your ear than the SR-L300 Limited.
The weight difference between the two is minimal with the Limited at 323g and the Jade II at 365g and they feel almost the same when fitted. The key difference is those cup and pad dimensions in terms of comfort with the Jade II just being a shade comfier for lateral pressure.
Both have a headband pressure dissipating strap under the main adjusting headband slider so both are very comfortable for vertical pressure.
These two stats cans have plastic cups though the headband system is made of metal on the Jade II compared to the all-plastic build of the SR-L300 Limited. Both have their fair share of creaks and noises when articulated.
The pro-bias 5-pin cable on the Jade II is poor compared to the better build and finishing of the SR-L300 Limited cable. Neither are detachable but the Jade II cable doesn’t inspire long-term durability confidence.
Performance
The SR-L300 Limited is the more efficient of the two headphones. We did an A/B using the dual-socket output of the Jade II amplifier and the Jade II needs a bit more current to reach similar volume levels.
Not a huge difference compared to something like the demanding VOCE but if you are used to a smaller setup such as the STAX SRM-D10 then that portable amp should be able to handle the SR-L300 Limited with no issues.
Tonally, these are quite different in timbre and staging. The Limited is more intimate sounding, not quite as expansive or as treble articulate as the Jade II whose balance is more emphasized in the upper mids and treble.
You get a fast and articulate sound with the Jade II with plenty of instrumental separation, high-frequency detail, and excellent layering. With the SR-L300 Limited, you get a bit more low-end emphasis, a bit more body and “oomph” with a richer timbre, and a more forward ‘bigger’ vocal delivery, especially around 1-2k.
Both lack any great sub-bass emphasis, this is not a 007 MK2 kind of low-end sound. However, the Stax SR-L300 Limited mid-bass has a touch more elevation from 80-100mHz and as such sounds a bit thicker and more planted. It also offers a bit more warmth and even-harmonic emphasis giving instruments a better bass fundamental compared to the ‘lighter sounding’ Jade II.
The Jade II is more linear and starts to roll-off around 100Hz on a slow drop by comparison. It does have a steady rise in dB approaching 1K but it doesn’t gather pace until the lower-mids. It lacks the authority and body of the STAX SR-L300 Limited low-end but makes up for it in terms of speed and excellent layering.
Kingsound KS-H04
$1000
Technical
The HS-04 has been designed as a quasi-portable electrostatic headphone to pair with their portable M-03 energizer amp. As such it is quite a bit smaller than the SR-L300 Limited with a smaller driver inside a traditional headphone form factor.
The KS-H04 has a lot more metal in its build than the SR-L300 Limited. Despite that, you will still argue that the Limited is the more premium of the two despite the fairly stylish design of the H04. On closer inspection, some of the components are a touch on the cheap side such as the fake leather slip-on pads, thin screws on the gimbals, and a basic stretch headband system.
The articulation and fit of the H04 are rather good, however, perhaps comfier than the SR-300 Limited. Two reasons for that. The first is the weight, the H04 is slightly lighter at 300g. The second is the cup shape which is oval compared to rectangular.
Both articulate quite well with multi-directional cup movements, however, the H04 clears the ear better with less lateral clamping to keep it steady. Thus, a slightly lighter and comfier feel compared to the SR-L300 Limited.
Performance
As with the Jade II, I find the SR-L300 Limited to be a little more efficient than the HS-04 when A/B’ed from the Jade II amp’s dual 5-pin output sockets. Again, not a huge amount but enough to notice a difference and enough to be twiddling the dial upwards on the HS-04.
Tonally, the HS-04 is a bit messy compared to the SR-L300 Limited. It sounds dark, warm but with softer bass and a boxy vocal performance as well as a loss of top-end headroom compared to the far more open-sounding L300 Limited.
Vocals are to the fore with that 1-2k elevation on the L300 Limited but have plenty of room to breathe whereas the HS-04 seems far more recessed and lacking in air. The low-end is much tighter, punchier, and authoritative also on the SR-L300 Limited compared to the softer warm sound of the HS-04 bass.
The dynamic range on the SR-L300 Limited driver is just so much better meaning you get a far more vivid and expressive layering of instruments and imaging cues compared to the HS-04.
Details are excellent whereas the HS-04 sounds smoothed over by comparison. You do need that brighter MS-03 solid-state portable amp to get an adequate electrostatic treble response on the HS-04 which is a shame.
Koss ESP950
$999.99
Technical
The ESP950 has been around for ages. It was launched I believe in 1990 and given the sub $1k price it is still selling very well to this day. Sometimes you can get it for a bargain under $700 but the SRP is still $999.
Technically it comes with an energizer box but you won’t get the optimal sound from this combo instead I recommend you get a converter cable to pro bias 5-pin and stick in a proper electrostatic amp to hear what it can really do.
The ESP950 is fairly cheaply made and to be honest the SR-L300 Limited looks a bit more premium in its finish. The ESP950 is made almost entirely of plastics and pleather or something similar to pleather for the cups, blocks, and pads, and memory foam coating on the single headband design. The SR-L300 Limited whilst using mainly plastics as a finish which is more premium looking.
The 350g ESP950 uses a more traditional single headband and memory foam cushion system with a spring steel slider. You will find there is more vertical or downward pressure on the ES950 as a result not including the fact it is the heavier headphone of the two. The SR-L300 Limited wide headband strap system has much better pressure displacement from the top down.
The pads on the ESP950 are fairly cheaply made fake leather also so sweating can be an issue and they do not really mitigate pressure quite as well as the Limited’s SR-L500 pads. Overall, the STAX is the comfier headphone with a better balance.
Performance
The SR-L300 Limited does the ESP950 better than the ESP950. Let me explain that a little bit more. Both are aiming for what I would call a fairly musical emphasis with a warmer over neutral or linear bass, a little bit more vocal or midrange emphasis around 1-2k and good energy from 8-10k onwards for headroom and air.
Key tuning difference includes the bass weight where the SR-L300 Limited has more of an 80-100Hz bump and sounds the weightier of the two and a more prominent lower-treble presence on the STAX.
It is really more about the driver on the SR-L300 Limited. For me, it is a technically better driver and that means a more resolving one with a better transient response from top to bottom.
Aspects such as bass snap, lower-mids note articulation, and treble presence are just tighter sounding on the SR-L300 Limited. Clarity on the vocal delivery is a bit better also, as is the headroom and perceived amount of space the SR-L300 Limited offers.
I am not saying the ESP950 is a dull-sounding electrostatic headphone, especially when connected to a good amp it can sound very good. Rather, the SR-L300 Ltd does the detail a bit better, the harmonic balance a bit more truthful and overall a more expressive musical experience that can lend to the perception that the ESP950 sounds a bit flatter.
Our Verdict
The SR-L300 Limited is a big of an electrostatic headphone bargain and thankfully a tuning that delivers a clear distinction from the likes of our previously reviewed Jade II headphone from Hifiman. There is less of an emphasis on an enhanced soundstage and an arena-like presentation and instead, more warmth, better body, good bass solidity, and a focused vocal performance.
As such I would class the SR-L300 Limited more on the intimate and musical side of things for a stats headphone but still with excellent resolution and an enchanting harmonic balance absolutely tailor-made for vocal lovers.
Sibilance is a big ‘no-no’ but neither is this smoothed over to get that tone just right. The L700 driver does the SR-L300 Limited some serious justice with a verve to its sound you will not find on other sub-1k stats cans such as the ESP950.
Pity there is only 800 of them but this could be a canny investment for collectors. I do believe you can still buy one brand new if you know where to look and I suggest you start looking because this is a cracking performer.
Stax SR-L300 Limited Specifications
- TYPE Push-Pull Electrostatic Oval Sound Element, Open-Air Type Enclosure
- FREQUENCY RESPONSE 7 – 41,000Hz
- CAPACITANCE 110pF (Including Cable)
- SENSITIVITY 101dB / 100V R.M.S. 1 KHz
- BIAS VOLTAGE 580V DC
- EARPADS High-Quality Synthetic Leather
- CABLE OFC Parallel 6-Strand, Low-Capacity Wide Cable, 2.5m Full Length
- WEIGHT 323.18gms Without Cable / 447.9gms With Cable
