Sennheiser headphones are among my favorites, and I’ve had a classic on-ear HD 414 SL in my recording studio for over 40 years. The company now also manufactures in-ear headphones (IEHs), such as the IE 300, which debuted at CES 2021.

I was eager to try out the IE 300 when I first heard about it in January. Now that I’ve tried it, I can confidently state that it’s the best in-ear headphone I’ve ever used.

Features of Sennheiser IE 300

The IE 300 is clearly targeted at audiophiles, as it lacks Bluetooth, noise cancellation, or phone microphones, instead opting for a 4-foot unbalanced cable with a 3.5mm stereo connector. A gold-plated Fidelity+ MMCX connector, which is seated in a recessed socket for extra strain relief, detaches the cable from each earpiece. Since the cable is detachable, you can replace it with a balanced cable if you want, and the company will soon sell balanced cables with 2.5- or 4.4mm connectors as optional accessories for $149.95.Sennheiser IE 300

Sennheiser’s 7mm Extra Wide Band (XWB) dynamic transducer is used in this IEH, which has an optimized membrane foil that reduces natural resonances and total harmonic distortion, which is defined to be less than 0.08 percent at 1kHz/94dB. A resonator chamber in front of the transducer reduces masking resonances in the ear canal, and the space behind the transducer is designed to eliminate reflections inside the housing.

As a consequence, the frequency response ranges from 6Hz to 20kHz (no tolerance given). Other features include a nominal impedance of 16 ohms, which is low enough to be easily powered by portable devices. Although the maximum sound pressure level (1kHz/1Vrms) is stated, I strongly advise against playing music that loud; it will ruin your hearing in just a few minutes.Sennheiser IE 300

The IE 300, like virtually all IEHs, comes with a variety of silicone and memory-foam eartip sizes, which is vital because having the right size for your ears is critical for getting the best sound and optimising noise isolation from any IEH. The included cable is strengthened with para-aramid that can withstand thousands of bend cycles, and each earpiece has an individually adjustable ear hook for stability.

Sennheiser IE 300 performance

I started with the largest ear tips available, both silicone and memory foam. Since my ear canals are relatively wide, I need large ear tips to achieve a good seal. The IE 300’s largest ear tips are around 13mm in diameter, and both types of ear tips did a good job of sealing my ear canals—in reality, they suit me better than the tips that came with most IEHs I’ve tried.

The memory foam tips are firmer than other memory foam tips I’ve tried, which is a positive thing. However, it took some fiddling to get them to sit comfortably between my head. I settled on 1More’s 14.5mm ear tips, which have always worked well for me.Sennheiser IE 300

I used my iPhone XS and an iFi hip-dac to listen to all of the evaluation tracks from Qobuz’s high-res library for this study. Unlike Tidal, Qobuz shows the resolution of each track, which I appreciate.

Frank Zappa’s 1969 album Hot Rats in 24/192 resolution was one of the first things I came across. It’s absurd to digitize an analog recording from more than 50 years ago at such a high resolution, but it’s done. Plus, “Peaches en Regalia,” one of my all-time favorite Zappa songs, was transcribed from the album and arranged for our big band by a friend in high school. It was challenging to play, but a lot of fun!

The sound on the IE 300 was extremely clean, and thanks to excellent imaging, I was able to clearly discern each instrument. The bass is mixed a little low, but that’s due to the recording, not the IEH’s reproduction.

Next up was Tom Petty’s 24/96-resolution “A Higher Place” from his posthumously released album Finding Wildflowers (Alternate Versions). The IE 300’s sound was crisp, smooth, full-bodied, and well-balanced, with excellent imaging. Petty’s vocals, in particular, were outstanding and completely normal.

Jon Batiste, Stephen Colbert’s bandleader, launched the fantastic album We Are at 24/44.1 last year. I listened to “Adulthood,” which features a lot of acoustic basses. With rich, authentic bass and natural vocals, the IE 300 sounded clean and clear. The sharp backbeat (I think it was rim shots, but I’m not sure) was very crisp, and the brass band at the end was lovely.

At 24/96, I put on Omar Sosa’s “Eretseretse” from his album An East African Journey for some African jazz. This track begins with a slow piano and a fast plucked African stringed instrument (I wish the liner notes named it) that features some very interesting panning effects in which notes skip back and forth across the soundstage. Drums, bass, and percussion add to the rhythm later.

The IE 300 delivered a clean, simple, accessible, well-balanced sound with excellent imaging once again. The piano and plucked string instrument, as well as the other instruments that joined in, sounded completely normal and cohesive.

I’m a sucker for healthy funk, and Dumpstaphunk has plenty of it. The group’s third studio album, Where Do We Go From Here at 24/44.1, features the super-funky, horn-laced “Itchy Boo,” which is led by Ivan and Ian Neville, sons of the legendary brothers Aaron and Art Neville, respectively. The IE 300 sounded clean, full-bodied, and well-balanced, with tight bass, natural horns, and excellent imaging, as I had anticipated. However, given the music’s limited dynamic range, I’m not sure why the recording needed 24 bits.

Moving on to chamber music, I listened to Carlo Gesualdo’s “Gagliarda del Principe de Venosa,” performed by Les Récréations on the album Scarlatti Sonate a Quattro at 24/96, one of my favourite Renaissance composers. For this piece, the ensemble includes two violins, one viola, and one cello, as well as a lute. On the IE 300, I could easily discern each instrument, and the sound was delicate, well-balanced, and open.

For something more substantial, I selected the fourth movement of Bruckner’s Symphony No. 3 in D minor, WAB103, as performed by the Wiener Philharmoniker under Christian Thielemann at 24/96. The IE 300 sounded gorgeous, as expected—clean, simple, well-balanced, complete sound with excellent imaging and dynamic range. I could clearly hear each section and solo instrument as part of a larger whole.

Comparison with 1More Quad Driver

The Quad Driver sounded almost identical to the IE 300, as my notes often put it. However, there were some minor variations. The Quad Driver sounded a little thinner and had a little more bass in most situations. The only exception was Jon Batiste’s “Adulthood,” where the bass was even more prevalent, if not overbearing. The bass was a little more diffuse and less well-defined on a couple of songs, such as Dumpstaphunk’s “Itchy Boo,” while the Gesualdo chamber music sounded only slightly warmer.

All of these variations were slight, with the exception of the bass on “Adulthood,” but the IE 300 never failed to deliver stellar sound.

Bottom line

I can’t say enough good things about the Sennheiser IE 300. It produces clean, transparent, accessible, full-bodied sound with superb imaging when used with the right ear tips for your ears, and the balance between bass, midrange, and treble is nearly perfect. Better still, the adjustable ear hooks hold them in place, and the detachable cable allows you to upgrade to a balanced link if desired.

The IE 300 isn’t cheap, at just under $300; it’s nearly twice as expensive as the 1More Quad Driver, which performs almost as well overall. However, as with most high-end audio, you’ll have to pay a lot more to get a marginally better sound.