AKG K551 Over-the-Ear Headphone Review

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Last summer I had the opportunity to review a pair of over-the-ear Bluetooth headphones from Harman Kardon. (Read the review.) I came away incredibly impressed by the sound, the build quality and the comfort. Judie read my review and was also impressed. She asked if she could try them out; I sent them to Texas, and they haven’t been seen since. 🙂

We were both impressed by just about every aspect of Harman Kardon’s Bluetooth (BT) over-ear stereo headphones. It turns out that Harmon Kardon is just one of the brands under which Harman offers headphones and other audio accessories. Each brand has its own distinct style and approach, but all are bound together by excellent audio and a commitment to creating the best user experience possible.

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That’s why I jumped at the chance to review the AKG K551 large over the ear studio headphones. Once again I came away impressed. Let’s dig into the details and specs before returning to that broad general statement.

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There are no two ways about it, these headphones are big. They come in a big box and inside that box are headphones that are big and round. I mean, they are really, really big. They are so big and round that, quite frankly, the first time I put them on all I could think about was Princess Leah’s funky coffee-roll hairdo in the original Star Wars movie. I don’t mean for that to come off as negative or sarcastic as it doe,s but I do think it gives a sense of just how large and how round these headphones are.

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And as it turns out, being so big is not a bad thing. Because these headphones are as large as they are, and because they go over the ear rather than sitting on the ear, and because they have humongous drivers (more on that in a moment) these headphones all but disappear. I know that is counter intuitive — huge headphones that disappear — but they actually do offer the closest approximation to listening to music without headphones at all that I have encountered.

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Let me explain that last statement.

The headphones are large enough that they comfortably surround my ears. At no point do they put any pressure directly on them. That means that, unlike in-ear or on-ear headphones, your entire ear is surrounded by the sound– just the way they are when listening to speakers. And the sound that surrounds your ears is big and rich. Sure, when you are wearing the K551s you are still wearing headphones, but the experience is substantially different from any headphones I have used — in a good way.

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Much of the excellent sound pumped out by the K551s is the result of each earphone having a 1-31/32-inch (50-millimeter) driver. This is the largest driver in any AKG product offering, and the result is immediately obvious. Big excellent drivers offer big, excellent sound.

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I know that some of you love specifications and numbers, so let’s run them down a bit more, and then do a walk around the actual accessory itself.

The AKG 551 feature:

1-31/32″ (50mm) drivers

Real Image Engineering

Outstanding passive noise reduction

Closed-back design

In-line microphone and remote control

Classic-meets-contemporary design

2D-axis fold-flat mechanism

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Okay, so I started this review with the experience of actually using the headphones. Now let’s turn to the actual physical product. These are premium headphones that come at a premium price. The build quality is impressive. The head band is thick and strong. It is constructed from metal and other premium materials. The hinges are also made from metal. They are rugged without being unrefined. The look and feel of these headphones is uncompromised, just as you would expect from premium headphones.

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The cushions that surround the ear are substantial, thick and provide plenty of padding. The result is that, while these headphones do not offer active noise cancellation, they do physically block out a good bit of ambient sound. That was another surprise that added to my positive thoughts on these headphones.

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These headphones are terrific, but let me be clear — these are not travel headphones. These headphones are designed for use at home or in the studio, and the company reinforces this fact in a number of different ways. First, the headphones don’t fold up into a small, relatively compact, unit. Sure, you can rotate the ear cups so they are flat, but the don’t actually fold up. As a result, if you take these on the trip be sure to have room to spare in your carry-on.

If you do take them with you when you head out, you will encounter the second way the company makes clear that these aren’t travel headphones. You see, you’ll have to find your own bag in which to carry them in. That’s right, the company doesn’t include a travel bag or pouch. That is especially odd since the company description of the headphones includes such statements as “take AKG studio-quality sound with you wherever you go”, and a reference to the folding design making them “easy to store or transport” — it’s quite odd when they don’t give you a case in which to ACTUALLY transport or store them.

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I find that lack of inclusion to be problematic in such expensive headphones. Even if these aren’t intended for travel, there should at least be some sort of storage bag included to keep them protected from bumps and scratches when you are not using them.

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There is another small disappointing surprise I discovered along the way; unlike most of the premium headphones I have reviewed, the cable on the K551 headphones is permanently attached. This is not a huge deal, but I do like those headphones that give you the option to connect the cable on either side. It is a small convenience I have come to appreciate.

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The other night I was watching a movie and I discovered that having the cord attached to the right ear-cup would have been preferable, but I got no joy. And it is not just the lack of convenience that is at issue — I like to know that, were the cable to wear out, I would be able to replace it for relatively little money. That is not an option here; and while I do not expect the cable to wear out, I am still a bit bummed by this.

Fortunately the cable is thick and quite strong; it is thick enough that it won’t tangle easily. The in-line controls and a microphone are the only thing that disrupts the cable as it runs from the headphones to 3 .5mm jack. Speaking of the controls, they are easy to use and are designed to offer a nice tactile feel and feedback.

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Put this all together and you get the following assessment — AKG made some choices that are not ideal, but they still ended up creating a terrific pair of high-end headphones. The AKG K551s are comfortable, sound good, block a good bit of ambient noise, and can be used for extended periods of time without causing ear and head fatigue. I have used the K551s to listen to music, to listen to audio book, and to watch television and movies on my iPad. Every experience with them has been positive.

The company is charging a premium price for these headphones, and that is exactly what they have delivered. That is why these headphones are the ones that are hung on my Just Mobile HeadStand waiting for the next time I want to use them.

The AKG K551 Headphones are available directly from AKG or from other retailers including Amazon. 

MSRP: $329.99

What I Like: Big, well-built and comfortable; Sound great; Inline control is easy to find by feel and works well; Comfortable enough not to cause ear or head fatigue

What Needs Improvement: AKG does not include a travel bag or case; Cord is permanently attached; Headphones do not fold up for travel

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About the Author

Dan Cohen
Having a father who was heavily involved in early laser and fiber-optical research, Dan grew up surrounded by technology and gadgets. Dan’s father brought home one of the very first video games when he was young and Dan remembers seeing a “pre-release” touchtone phone. (When he asked his father what the “#” and “*” buttons were his dad said, “Some day, far in the future, we’ll have some use for them.”) Technology seemed to be in Dan’s blood but at some point he took a different path and ended up in the clergy. His passion for technology and gadgets never left him. Dan is married to Raina Goldberg who is also an avid user of Apple products. They live in New Jersey with their golden doodle Nava.

2 Comments on "AKG K551 Over-the-Ear Headphone Review"

  1. How to extend the cable and listen? can’t get it to work, have to hold in the pause button to get the normal sound?

    • I’m sorry but I’m not sure I understand the question. Can you explain a bit more?

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