STEREO GUIDE verdict
+ extremely high-resolution, clean sound
+ ultimate dynamics and efficiency
+ deep, fast bass
- Sound analytical to merciless
- sometimes too slim in bright shots
Sound: tonal balance / transparency9.1
Sound: Bass / Dynamics9.6
Practice / Connectivity9.2
Price / Performance9
Even in the age of True Wireless, Bluetooth and noise-canceling, the portfolio of wired in-ears is growing at headphone specialist Sennheiser. In the high-end segment, they even rely completely on cables. Now, there was a gap in the range between the affordable IE 300 and the fairly upscale priced IE 900, both of which we had in review. The closes the Sennheiser IE 600 for 700 euros recommended retail price. With this pricing, we also see it as a challenge to the Beyerdynamic Xelento 2, which costs a bit more and could even place itself slightly ahead of the most expensive of the Sennheiser series with its natural, unagitated audiophile sound.
Metal printed instead of milled
So what distinguishes the IE 600 from its more expensive brother and its fiercest rival? All three have a metal casing. But in the IE 600, this is neither milled nor assembled from several castings, but printed. Neither steel nor aluminum come into question for this; instead, Sennheiser uses a zirconium housing manufactured in Germany. This metal, which is not dissimilar to titanium in terms of its metallurgical properties, is now expected to show all its advantages over steel and aluminum. The already corrosion-resistant transition metal is used in an alloy that is supposed to guarantee better hardness and is additionally hardened with extreme cold after the mold is made.
The main advantage of using it as an InEar earpiece is that it can be printed flat to create any shape. This is used in the IE 600 for a complex design of damping channels and resonance chambers. A double resonance chamber inside the cabinet, for example, is responsible for linearizing the frequency response in the range where the ear is particularly sensitive to coloration. In addition, the design is said to reproduce low frequencies over the audible range without resonance exaggeration always with perfect impulse processing. The manufacturer emphasizes that, thanks to state-of-the-art printing processes, the tolerances are even tighter than with milling and casting processes anyway.
In chemical terms, this is an amorphous metal. The surface also looks a bit rough under a magnifying glass or in a macro photo. But this is deceptive.
One for all
The 7 mm driver inside is also used in other models. Sennheiser calls it “True Response” and emphasizes the incredible frequency range of 4 to 46,000 Hz. This is not a particularly important value for hi-fi applications. However, we believe the manufacturer that the actual frequency range to be reproduced between 16 and 20,000 Hz is so far from the driver’s mechanical limits that it can be used full-range.
This is because Sennheiser uses a full-range driver instead of a multi-way arrangement, which is not uncommon in higher price ranges. The driver is driven by a classic voice coil, so it belongs to the dynamic drivers.
The manufacturer specifies the impedance with 18 ohms. Together with a high characteristic sound pressure, this should ensure that sufficient dynamics are available even when connected to less powerful amplifiers in smartphones, tablets and notebooks.
What else is there?
The manufacturer supplies two variants for the cabling: An unbalanced 3.5 mm jack and a 4.3 mm Pentaconn. The latter allows fully balanced control if the amplifier or DAC has a corresponding jack. However, there is no classic headset cable with microphone.
The cables are always routed over the ear cup from above. The first few centimeters from the transducer capsule are reinforced with a wire that guarantees a really secure fit.
The Sennheiser IE 600, like most in-ears, needs to be placed really close in the ear canal. Earpieces are included in three different sizes and two material variants – each as a thin rubber seal and memory foam. The metal sound channels must go relatively deep into the ear canal to seal tightly.
Do not rush with the ear pads
Despite the abundant supply, new Sennheiser IE 600 owners should take their time for selection and insertion. Some colleges had a hard time with the rubber adapters. The gradation of sizes is quite rough, and even the large one cannot always be placed conclusively in the ear canal.
Because they have to go quite deep into the ear canal until they really close tightly. After all: A mismatch is noticed immediately, in the form of thin and bass-free sound. In practice, the reviewers in our series found a perfect fit with the medium or large foam adapter.
The housing shape is practically no different from the IE 900. In other words, the IE 600 lies very flat in the ear and it doesn’t bother at all when you lie on your ear with the in-ear inserted. On the other hand, one often feels that “something is there” in the ear. As long as it doesn’t pinch, however, we don’t see any problems with long-term suitability.
How does the Sennheiser IE 600 wonder headphone sound in the review?
Due to the technical similarities, we were naturally interested in how the IE 600 performs in direct comparison to its sister model, the IE 900, which is twice as expensive. After a long time of testing many pieces of music, we can state: Both are very similar tonally and in terms of qualities. In other words: extreme treble resolution with slag-free cleanliness, and a driving dynamic with breathtaking level reserves. Neither the IE 900 nor the IE 600 can conceal their character as in-ear stage monitors: This is how one ideally imagines the live sound, which remains as transparent as musicians want it to be, even with dense mixes and high levels.
Detail resolution can be described as extremely precise, with a tendency towards somewhat accentuated upper treble. Even though this emphasis is a bit higher and thus less obtrusive than in the IE 900, the IE 600 always remains a merciless monitor in the truest sense, though. No matter if you listen to electronic music, hard rock or big band jazz, you always get the full dynamic package without a second of breather. Depending on the mixture, it may even be a little too much precision around the top. The Sennheiser IE 600 only sounds relaxing with deliberately soft and warm recorded tracks, because it always remains transparent and clean.
Despite all directness, it projects a surprisingly credible space for an InEar. It is displayed quite close to the head and is not too big either, but it is absolutely adequate for classical and acoustic jazz recordings as well.
In-ear headphones with powerful drive
The two Sennheisers take somewhat different paths in the low bass: while the IE 900 pushes mainly with mass at the bottom, the IE 600 always stays on the fast, deep and crisp side. From a sound fidelity perspective, this is more of an advantage over its more expensive brother, but tonally lean recorded tracks tend to tilt towards the bright side as a result. With somewhat warmer or softer recordings, on the other hand, it gives voices a fair amount of volume and mellowness.
It proved to be best in class by far in terms of dynamics and efficiency: What comes out of the IE 600 in terms of level, impulse peaks and cleanliness, even at the voltage-limited output of an iPhone, is unrivaled.
Sennheiser IE 600: review conclusion and alternatives
There are some strong competitors in the headphone segment between 500 and 1000 Euros. Our favorites in the passive segment and the references for listening comparison are the Final B-3 and the Beyerdynamic Xelento 2nd generation. If you prefer a warm or mellow tuning, you should definitely consider the Final or, if you prefer a balanced-neutral tuning, the Beyerdynamic. The Sennheiser IE 600, with its tonal focus on the highest resolution and dynamics with crisp low bass, is aimed more at buyers who also prefer stage and club as places to listen to music. The bottom line is that it also almost matches the Sennheiser IE 900, which costs twice as much, and only has advantages with a bit more detail resolution and bass pressure.
Technical specifications Sennheiser IE 600
- Manufacturer’s suggested retail price: 700 euros
- Type: In-Ear
- Transducer principle: Dynamic
- Weight: 5 g (each)
- Features: 3 pairs of silicone ear adapters (S, M, L), 3 pairs of foam ear adapters (S, M, L), carrying case, connection cable asymmetrical and symmetrical Pentaconn
- More at: www.sennheiser.com