Simple Man’s review – Sennheiser IE 400 Pro (350 USD)
This is called simple man’s review because they are based on the sound of these earphones directly from my mobile phone (HTC 10), using 320 Kbps mp3 tracks. No expensive gears nor lossless tracks,no EQ, and all that hi-fi stuff.
Product Specs :
Driver: 7 mm “broadband transducer” Single Dynamic Driver
Impedance: 16 Ohms; Sensitivity: 123dB/mW
Weight: 18g
Cable: 1.3m; proprietary detachable cable (Compatible only with IE 400 and IE 500 Pro - Not compatible with IE 40 Pro)
Shell: Hard Plastic Shell
Nozzle: ~5mm
Total Harmonic Distortion: < 0.08 %
Release year: April, 2019
Accessories – 5/5
The unboxing experience was really nice, and the presentation is elegant.
Apart from the earphones themselves, we get the following accessories.
- 3 Silicone adapters (S, M, L)
- 3 Foam adapters (S, M, L)
- 1 Transport case – really spacious and can hold 2 of these earphones easily.
- 1 Cleaning Tool
- 1 6.3 mm jack-adapter
What more can one ask for ?
Build – 3.5/5
The build quality is very similar as its little brother IE 40 Pro, which had no flaws to speak of. The hard plastic shell and the black wires are retained in the IE 400 Pro (Note that the IE 40 Pro connectors are not compatible with the IE 400 Pros). The plastic shell might sound cheap, but this really keeps the weight of the housing and wearing comfort at an optimal level. They’re also using their expensive 7mm micro driver in this model, the IE 40 Pro had a larger 10mm driver. I’m happy with the build in general as I had no complaints against the design or build of the IE 40 Pro.
There are, however, a couple of small enhancements incorporated in the IE400 Pro if you take a closer look. The earphone nozzles now have a protective mesh. This is very thoughtful, and for the asking price I would have been slightly bummed if they forgot to add this trusty mesh. . IE 40 Pro instead has some foam inserted into the nozzle to keep dust out. There is a change in the nozzle length and thickness in the 400 and 500 Pro models, the IE 40 Pro has a slightly longer and thinner nozzle. Detachable cables are great and easy to use and replace.
EDIT 23.01.2020: AFTER 10 months of continuous use and tip rolling with
the IE500 Pro which has the exactly same build as IE400 PRO the driver housing in the left earpiece just popped out yesterday. To be fair i tried so many tips with these IEMs (including ones with smaller diameter than the nozzle, twisting them back and forth, etc.) I had to re-glue it back in. Sound quality is the same. If you're not playing too much with tip rolling, you should be good! Bringing down the rating in this section from to 3.5 due to this.
Fit – 5/5
Fit is excellent. Over ear universal fit can’t get better than this. The slim housing sits very comfortably and seamlessly in the ear concha. Sleeping with this won’t be a problem at all.
Isolation and leakage – 3.5/5
Sound Attenuation is rated at <26dB, and they are OK with music ON. Perfect for indoor use, however, if you are talking a walk outside, outside noise tends to creep in letting you know of your surroundings. The earphones even allow you to have a conversation without taking them off when no music is playing, as would be preferable for on-stage musicians to get together for a small chat between tracks. Sound leakage is very minimal at normal listening levels and shouldn’t bother a loved one trying to sleep.
Microphonics – 5/5
None. There is no touch noise from the cable, and walking with these are a pleasure indeed. Just make sure the earbuds are placed securely in the ear and you wouldn’t notice any cable noise.
Drivability – Easy to drive with a smartphone. With my HTC10s i’m mostly between 40-60% of the volume. It gets a slightly louder than the IE40 Pro, as the sensitivity is nudged a bit higher here.
Before we get to the sound-
Eartips: I’m using the stock tips, which have some foam filter in it. These tips are right in between Final E tips and JVC spirals in terms of bore width. I think the stock tips works as good as any.
Sound –
The general signature can be called balanced, again very similar to IE 40 Pro. They sound very similar. With the Pro series Sennheisers are going for what they call a “precise” sound as opposed to neutral. This is basically a balanced tone with a little nudge in the bass to sound more natural, and a little push in the treble to get that treble extension and splash.
We have good bass emphasis, the mids aren’t forwarded like ATH or Donguri, for instance, they play on the right level without sounding restrained. The highs really extend well and display great amount of clarity. It’s up there with the masters in terms of detail retrieval. Every treble touch with the snares and crash will be delivered precisely to the listener’s ear. We can see more about sound in the following passages.
Soundstage:
The soundstage is nice and wide. They really stretch from left to right and if you like wide soundstages the IE Pro line-up will not disappoint. The stage is not very tall seeing they tend towards a monitoresque presentation. The presentation is rather lateral, with good pin-point localisation of individual instruments. They never get clinical so as to distract from the music, thanks to the bass emphasis which keeps things together. Overall, the stage is very similar to ER4XR
Bass:
The bass delivered by IE 400 Pro is punchy and impactful. If your track is bassy, you will feel all the bass fun intended by the artist. The same holds true for the entire series. You get that impactful bass with very decent definition and separation. The sub-bass quantity is slightly below the mid-bass from what I hear. The bass is tight and defined, and mostly stays in its spot without disturbing the clarity of the mids. The mid bass impact is also good, it is the kind of bass that hits and lets the impact sink in for a moment before vanishing. Not the fastest driver. The timbre and natural quality of the bass instruments come through very authentically. The reverbs from cello and double-bass can be enjoyed to the fullest.
Mids:
The mids are neither forwarded nor pulled back to sound like a V-shaped tuning. The slight bass emphasis and treble tilt gives it a kind of reserved positioning. The intention is to present the mids in a more level-headed manner, rather than boost the mids to get that intimate W sound. Staying where they are, the mids never get out of the spot-light and plays with authority and great clarity, even. The vocalists don’t pop out (unless recorded that way) and sing at a decent distance in the stage. There is a certain airiness to the mids and they sound breezy and happy. This probably plays out more due to a certain drop in the sub-bass emphasis. And of course, with a balanced signature the timbre is mostly right on with a dynamic driver and the IE 400 Pro scores in this respect. Mids sound very natural and defined. The instrument separation is also very evident and commendable.
Treble:
The treble really extends well beyond 10Khz unlike many IEMs that I’ve had the pleasure of using. Again, true for the entire line-up. Every tick on the snare is clearly presented in its accurate position. The signature tilts bright due to a certain emphasis in the treble region. It’s not overly done, but one will not go and call this smooth (think Final E series, or even Etymotic for that matter). As a result, there is great clarity in the region which sounds crisp, sharp and refreshing. This also gives that little splash which some of us audiophiles crave in an IEM. Due to the great extension here, the transient harmonics are very impressive. If you have songs with a lot of echoes and such, think Pink Floyd or Chemical Brothers, both the IE 400 and 500 Pro sound really mesmerising. The dying echoes of the strings and the high-notes have a beautiful spread in the soundstage and makes for an immersive experience.
Comparisons
Round 1 – Vs Sennheiser IE 40 Pro (~100 USD)
Obligatory comparison with the lesser brother. Let’s see if the IE 400 Pro sounds a whole 250 bucks better than its younger brother.
The general signature of the two is very similar. IE 400 Pro gets slightly louder in the same volume than the IE40 Pro. The bass is tighter in the IE 400 Pro, and also has a slightly lesser sub-bass slam. IE 400 has slightly better bass definition as well, being relatively faster. The mids, also pop out slightly better with the IE 400s, and is clearer by some margin. Vocals comes through with better intelligibility compared to the cheaper IE 40 Pro. The IE 40 Pro’s highs are little more on the splashier side and have some rough edges. This is tamed in the IE 400 Pros, and they also sound much clearer and have more precise positioning. As a result, they also display better micro-definition in the treble.
Clartiy and definition is better throughout the spectrum with the IE 400s compared to the younger brother.
You can say, these are a direct upgrade to the IE 40 sound, not very different from how the IE 500 Pro is a direct upgrade to the IE 400 sound.
Round 2 – Vs Acoustic Research AR-E10 (discontinued)
Fairly new IEM released by Acoustic Research. I wanted to do this comparison to check how the IE 400 Pro stands against this hybrid IEM, which has very good resolution despite having a big meaty bass.
AR E10 has a big emphasis in mid-bass, and sub-bass. The mid-bass bloom, although not very bloaty, is very evident and colours the signature dark. The driver being a little on the slower side does not help as well. This also masks certain mid frequencies and affects clarity. The E10 are also tuned towards a W-shape response, with the mids/upper mids pushed up to add extra clarity, and has a little emphasis on lower treble as well to give that shimmer up top . When switching to IE 400 Pros, the increase in clarity is quite surprising, and we can readily see how the linear response greatly helps to increase resolution and clarity throughout the spectrum. The driver is tighter, mids clearer, and vocals also have better clarity.
Easy win for IE 400 Pro.
Round 2 – Vs Olasonic FLAT4 NAMI (discontinued)
Only challenging comparisons here on out. FLAT4 NAMI is renowned for its treble clarity and vast soundstage. They are armed with 2 dynamic drivers.
NAMI’s separation is very distinct in their super-wide soundstage. The treble is clearly up in the mix, and the extension is really great. Treble transients fly through the shimmery soundscape. The Nami also hits a little close to the sibilance region, never really touching it, ever teasing. The upper-mids emphasis is also apparent with NAMI. The bass has great definition and decent impact.
Switching the IE 400 Pro, we immediately notice more weight in the bass, with great impact and fullness. Compared to the wide and spread out presentation of the NAMIs, the Sennheisers sound rather intimate. The mids are also clearly in front of the mix in comparison. The NAMIs sport a U shaped tuning where the vocals are slightly pulled back in relation. NAMIs are an easily brighter earphone and the treble splash comes across as slightly thinner. The relatively lesser sub-bass quantity of the NAMIs also help to extract more definition from its bass.
This round must be called a tie. The Senns score some points with vocal clarity and a slightly closer, true to source presentation. The NAMIs are a touch more resolving, and extract slightly more details, but at the expense of sounding slightly harsh and taking the bright signature. IE 400 Pros sound more balanced and the warmth and splash nicely even out for a natural presentation.
Round 4 – Vs Etymotic ER4XR (~350 USD)
I use these with SpinFits. Another relevant and challenging comparison since they are similarly priced.
The Etymotic clarity impresses straight-away, and being XR, the bass is also delivered precisely with nice impact. Detail extraction is, well, Ety level. Mids are crystal clear, and the vocals precise. They do reach a little close to sibilance with the zzzs and sssszs.
Switching to the Senns, we notice better attack and impact of the dynamic driver. The IE 400 Pros add a dash of warmth coming from the ER4XR. Sub-bass impact seems similar, with some added mid-bass attack in the IE 400 Pro. Clarity of the mids are slightly better in the Etys, with the vocals coming through as dry, neutral. The 400 adds that little warmth and soul to the sound. The highs of the Etys are rather thin and the quick hits don’t help much in delivering any sense of depth to the treble. Here, the Sennheisers portray a more convincing treble presentation. The Cymbals and crashes are more life-like, with that added weight. The dynamic driver also has impressive extension into the treble, and yet avoid sounding bright or thin, like the Ety.
The Etys sound a touch cleaner, and leaner, sacrificing warmth and bass impact to the Sennheisers. You might get bored with the Etys, not so with the Senns
Round 3 – Vs Sony EX800ST (~250 USD)
Another single dynamic with a massive soundstage. Also tooted as a monitoring earphone. Let’s see how this fight goes.
Amazing soundstage depth and width, with great clarity in the mids- this is EX800ST. The bass is precise and linear. Mids get the necessary warmth and timbre is top notch. The upper mids are slightly bumped to sound really nice.
Switching to Sennheiser IE 400 Pros, the sub-bass impact is better, with equal warmth spreading to the mids. The treble is slightly nudged up front with the Sennheisers, which make it the brighter of IEM. The notes are all slightly weighty with the Senns, with vocals carrying a little more body. There is better instrument separation with the Sonys as they put their wide stage to perfect use. The Sennheisers squeeze all the sounds a little closer to each other, thereby giving us some extra intimacy as well.
Sonys score with Soundstage, separation, mid-bass, upper-mids.
Sennheisers score with sub-bass, treble, cohesiveness, also outdoor proof.
I had to go back and forth between the two so many times, and i would say they stand in the same tier, while leaning slightly toward Sony, because they have that upper-mid nudge.
Round 5 – Vs Ultrasone IQ Pro (~450 USD)
A very highly competent hybrid from IQ Pro packing 1 BA and 1DD, also aimed at monitoring professionals. I can already say we are near the top of the food-chain here.
The IQ Pro soundstage is vast with great depth, width and height. They display amazing clarity and timbre that it’s quite astonishing. Instrument positioning and spacing is also impressive. Sub-bass is reserved with decent dynamic impact and the driver is quick and resolves extremely well. IE 400 Pro impresses again with equal clarity and I would go so far to say slightly better resolution as well. Despite delivering a much better impact with sub-bass, we can see that the vocals are a touch clearer in the IE 400 Pro, and slightly forward in comparison. The upper treble as well extends further, and you hear slightly more details in the mix.
In terms of sheer detail retrieval and resolution, the IE 400 Pro might just edge the IQ Pros out. Where there IQ Pro impresses is with its greater soundstage, layers and instrument positioning. The Senns hold their lateral positioning, with a relatively constricted space, not so different from Etys, which is preferable for monitoring purposes. Before comparing I thought IE 400 Pro might be on the losing end of the stick. I’m completely surprised by how the Sennheisers rose up to the occasion with their clear and dynamic sound!
Round 6 – Vs InEar Stage Diver SD2 (~450 USD)
OK. This is summit. SD2s loaded with 2 BAs, are a bit pricier than the IE 400 Pros. We already saw how the SD2s put up with its elder brother IE 500 Pros’ punches. Let’s see how the 400s fare against the SD2s.
SD2s are immensely clear with a strictly linear bass, that adds a nice warmth to the mids enabling excellent timbre reproduction. The soundstage is deep and wide quite similar to the IQ Pros. And the sheer clarity in the mids is staggering. The notes have good depth and weight to them and comes across as very real. Treble extension and clarity as well is top notch.
Switching to IE 400 Pros, we can immediately notice a bigger sub-bass reach and impact, but at the same time the driver this time is a bit slower and we can notice layer of muddiness in the bass-mid region. The constricted soundstage does not play to the IE 400 Pros advantage as well. The Sennheiser highs show impressive extension and reach, but not enough to out-do the SD2s in this regard. The note weight is also slightly lacking in the IE400 Pros and they come across as slightly thin. The sheer clarity and greater soundstage earn a convincing win for the SD2s this time. For 350 bucks, the IE 400 Pros are still unbeatable from my little experience.
Bonus round: Vs IE 500 Pro here in the detailed review.
A word on the single dynamic driver – Sennheiser, with their Pro series, have more than convincingly busted this whole “BA driver for Clarity” myth. The treble resolution and the vocal clarity are TOTL – especially with the IE 500 Pro. Using the dynamic driver also means that bass is on point, and the timbre is closer to the natural sound. Sticking to the single dynamic is also a class-act and I really commend Sennheiser for not condescending to take the multi-driver route.
Both final and Sennheiser will have my respect for sticking to their core values.
Overall Sound rating of Sennheiser IE 400 Pro: 9.1 / 10
Vocals 4.2/5
Soundstage 4.4/5
Instrument Separation 4.2/5
Positioning/localisation 4.3/5
Details 4.3/5
Timbre 4.3/5
Conclusion –
The entire Sennheiser IE Pro line-up are decently priced and deliver great quality sound for the money. The IE 400 Pros are a significant upgrade from the IE 40 Pros. They are highly resolving and stand to contend against the best in the price range. The IE 400 Pros also take you one step closer towards the fully realised 7mm driver, which is the IE 500 Pro. If you're looking for a fun, detailed sound you cannot go wrong with the IE400 Pros.
I've own these for a year, having picked them up in a Sennheiser sale for less than 200euros.
They truly sound fantastic. I've recently coupled them with IE Pro Bluetooth cable which has an amazing battery life with not much effect on SQ relative to wired (though midrange depth and details improve if coupled with a decent DAP).
Truly great an IEM for the price (especially if you can get them at a discount).