Review – Dekoni Audio Blue – Fostex/Dekoni HiFi Audiophile Planar Magnetic Headphone

Dekoni Audio quickly gained a reputation among headphone aficionados for their high-quality replacement ear pads that fit a wide-range of headphones. When we were given the opportunity to review their first audio product outside of their comfort zone of replacement ear cups, we said “Sure!” The Dekoni Audio Blue – Fostex/Dekoni HiFi Audiophile Planar Magnetic Headphone are the result of their partnership.

Dekoni Audio and Fostex teamed up to create a custom variant of the Fostex T50RP MKIII Headphone. According to Dekoni, “Utilizing the Fostex Planar Magnetic Drivers and Body, the addition of the Dekoni Hybrid Ear Pads and other proprietary changes makes this headphone a better version of the original by being less fatiguing and smoother all around with an extended bass response.” The headphones now ship with two sets of ear pads, an “extra set of Dekoni Audio Elite Velour Ear pads that utilize the Premium Slow rebound, high density memory foam Dekoni is known for.”

Most companies play up the quality and status of their products with fancy packaging, hand rubbed wooden cases, velvet lined carry bags, flashy accessories, and so on. If you are one of those customers, who judge the product by the quality of the carrying bag and accessories they ship with, then the Dekoni Blue will let you down. 

Let me be clear here. The headphones, which are solidly built and tough as nails, are at the same time, one of the least pretentious high-quality headphones we have ever tested.

Why? Because the Dekoni Blue doesn't ship with anything except an extra set of ear pads, a headphone jack adapter, and the cardboard box it ships in. You would be hard pressed to find a less pretentious presentation. We have a stack of gorgeous wooden presentation boxes in the attic, which haven't been opened since we took the headphones out of them. Personally, we would rather see a more affordable product with higher quality production builds then unneeded swag. 

What surprised me about the Dekoni Blue was that I wasn't prepared for the audio experience that followed. Part of the reason the headphones were a surprise, is that, they feel, plasticky. They just don't feel luxurious in terms of the build. They have the feel of the tough generic headphones they used to have in Junior High School that could withstand a lot of abuse. As opposed to beautiful hand rubbed wooden and metal speaker enclosure cups, helping to denude the Amazon watershed, the Fostex approach is a single lightweight molded enclosure.

Does a fancy wood enclosure mean better sound? Listening to the Dekoni Blue lays waste to that theory. For us, “It's the sound quality, stupid,” our variant on “It's the economy, stupid.” Our editor Nancy thought they felt like comfortable hearing protectors. And yes, they are really are that comfortable. The Dekoni Audio Blue – Fostex/Dekoni HiFi Audiophile Planar Magnetic Headphones are a lesson in not judging a book by its cover.

Which is to say, that the first time I went to use them, I had kind of spaced on the fact they had planar drivers, as well as just coming out of a cardboard box. It was late at night, after a particularly hard day, and I plugged them into the fine Oppo HA-1 headphone amplifier with an audiophile grade ESS DAC. The HA-1 (now legendary and almost impossible to find) is a pure Class A amplifier, and able to drive everything we have ever thrown at it.

Using Amarra 4 Luxe, I cued up Macy Gray's superb award winning Chesky Records album, “Stripped”, plugged in the headphones, and absentmindedly hit play on Amarra 4 Luxe. With my attention focused on doing some editing in Adobe Photoshop Lightroom CC, I wasn't quite prepared for what happened next.

Suddenly, it like “Yo, Dude!” The quality of the sound just floored me. I simply wasn't expecting it. After a few tracks played, a light bulb went off, and I remembered the Fostex T50RP MKIII headphones the Dekoni Blues were based on. Fostex is better known to studio habitués, than golden-eared audiophiles seeking the latest glitz. But to those who live in recording studios, Fostex has an impressive reputation.

As Macy Gray's vocals and the backing instruments surround her, in pristine Binaural + sound, the precision and transient response of the drivers became clear. Chesky Records is known for its carefully recorded titles, especially their new Binaural Series. Jeff Lanier produced the title, resulting in a stunningly produced recording. The soundstage is open and airy; the bass is smooth, yet punchy. They don't have the sterile and neutral feel of strict studio reference units, but are musical and believable. Most of all, they are enjoyable.

What's different about the Dekoni Blues? Boasting a cool blue finish, and an extra long (3-meters) detachable cable, these are seriously good headphones. According to Dekoni, “With Redesigned Blue cups, a new Inner Baffle, and Dekoni’s Hybrid Ear Pads made especially for this Headphone you are left with what some are calling the most comfortable headphone around. By using the fenestrated Sheepskin on the inside of the pad you regain some of the mid frequencies that were lost when listening to the stock T50RP MK3.”

We didn't have a stock T50RP MK3 to confirm those claims, so we can only listen to the Dekoni model. Fostex has several versions of the headphone, and the T50RPmk3 is described by Fostex as “Semi-Open for 'Flat and Clear' Sound.” Other similar models from Fostex include the “Closed for 'Focused Bass” T40RPmk3, and “Open for 'Deep Bass” T20RPmk3. They all share similar specs, at approximately the same price. Fostex rarely uses the term planar-magnetic, they have their own their own nomenclature; “The unique planar-magnetic (also known as orthodynamic) driver unit incorporates Fostex's proprietary Regular Phase (RP) Technology diaphragm.”

Typical of a semi open-ear planar design, they weren't designed to block ambient sound, so they aren't a great choice for travel, or office cubicles. The soundstage is open, and the tonal transitions and clarity are as smooth as liquid gold, they had a nice solid, gutsy bottom end, just were capable of handling any source we chose. Best of all, at under $200, they might be one the best bargains in audio. The sound is open and airy, with a lighting quick response. The new ear cups are very comfortable, and stayed so even during long hour long listening sessions. For the music lover seeking a comfortable fit, open and airy sound, flexible with a variety of genres, with a flat yet musical, no compromise headphone at a bargain price: the Dekoni Audio Blue – Fostex/Dekoni HiFi Audiophile Planar Magnetic Headphone comes highly recommended.

Harris Fogel, Nancy Burlan, & Thomas Fogel posted 11/20/2018

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