I’ve had extensive time with each of these headphones, and there are some marked differences between them that will most certainly affect your decision making process.
I’ve personally owned an HD 600 since Christmas of 2016, and have demoed an HD 650 on many occasions. In fact, I have one in the apartment right now! A good friend of mine, Craig Boyles, has lent it to me many times and I’m really grateful that he has.
In fact, nowadays I kind of prefer a 650 over the 600, but we’ll get into all that in a bit.
The HD 598 is another headphone that was lent to me by a good friend I met at Audio Advice by the name of Luke. He uses his for gaming and it really is perfect for such activities. We’ll also touch on that later as well! 🙂
First, let’s get into the specifications for each of these, shall we?
Now that the boring stuff is out of the way, let’s get into the build of each. We’ll talk in depth about Amplification and the like as well, so don’t fret!
The build quality of the Sennheiser HD 598 is definitely not bad at all. It’s a fairly lightweight headphone, but feels pretty good in your hand. It’s not going to wow you in any way, but it’s serviceable and adequate. It doesn’t feel as lightweight as something like an AKG K240, but it’s still a little flimsy in your hand.
The cups here are of course velour, the headband is plastic with leatherette padding, and there’s that element of high gloss burl wood detail complimenting premium metal mesh for the grilles. All in all, it feels pretty solid with all things considered.
The 598 terminates in a 1/4″ jack and comes with a 3.5mm adapter. The cable is also detachable.
The HD 600 is definitely heavier, and feels a bit more substantial by contrast. We’ve still got mostly plastic, but there’s also elements of carbon fiber, and of course velour for the ear cups. The headband padding here is a soft foam and feels great to the touch.
The 600 is also larger than the 598. The headband adjustment is a thin type of metal, whereas with the 598 it’s plastic. The plastic is thicker, but doesn’t necessarily feel more sturdy. The 600’s headband adjustment has always kind of baffled me. It’s really nothing like I’ve ever seen before. From first glance, the piece that connects the headband to the cups looks kind of fragile, but it’s held up remarkably well over time.
Even though the 598 is all plastic, it’s a deceptively sturdy plastic and holds up very well to rough handling. I wouldn’t throw it across the room like an HD25, but it’s surprisingly solid for it’s weight and build.
For the HD 650, everything is pretty much the same as with the 600, with a couple of small differences.
The padding is still foam on the 650, but instead of 4 individual pads, it’s one pad that has a sort of crater in the middle.
The wire on the HD 600 is thinner and feels a lot cheaper than the HD650’s. It’s also a lot harder to pull out. The 650’s wire is a breeze to get out and it’s also thicker at the base. You’re easily able to grasp it and pull with no issues. I found myself worrying about damaging the 600’s cable in trying to pull on it. It’s very small at the base and seems to be lodged in much too tight. That said, all parts on both are replaceable: Grilles, Padding, Wiring, etc. These are headphones that should theoretically last you a lifetime with proper care!
The other difference is that the 650’s cable terminates in a 1/4″ jack and comes with a 3.5mm adapter. Sennheiser really wants to make it clear that this headphone deserves separate amplification in the form of a 1/4″ jack on your headphone amp of choice. Click here to skip to the Amp section!
On the 600, the termination is a standard 3.5mm jack and it comes with a very nice snap on adapter with a black base. What I appreciate about this adapter is that it’s instantly recognizable. I always know exactly which one goes with the 600 in a sea of other screw-on adapters that all look the exact same. 😛 Being an audiophile is tough work! Lol.
The comfort on all three of these headphones is excellent, but you’ll find some slight differences between the 598 and the 600/650.
Both the HD 600 and 650 are infamous for having very tight clamp pressure on your head at first. It does open up over time, so there is really nothing to worry about. I personally just waited it out and was fine. Your mileage may vary. If you do find them too tight at first, you can always stretch them out over some books or something similar. Just be very careful! The HD 600’s headband in particular has been known to snap under pressure, sort of like Henry Hill in Goodfellas. 😛
By contrast, the HD 598’s clamp pressure isn’t as tight, but it still fits very snugly on your melon. In all honesty, the 598 may just be the most comfortable headphone I’ve ever worn. You pretty much forget you’re wearing it after awhile, and I really never have to make adjustments.
The HD 600 and 650 are equally as comfy, but it will take some time for both to open up. Once they do, you’re in for a real treat! Do note that even after both open up, they still sit a bit tighter than a 598.
All in all, I would rate the 600/650 as about equal in comfort. The HD598 will be a bit lighter on your head and sit a tad more loosely.
Starting with the 598, you’ll notice that the sound is very very relaxed. This is the best way I can describe the overall character of this headphone.
Nothing is really going to jump out at you. The bass is pretty good, but does have a tendency to get kind of “bloomy” at times with certain files, and especially at higher volumes. I find that harmonic distortion is fairly common with this headphone, but then again it really doesn’t need any power at all at 112dB Sensitivity. What is Sensitivity in Headphones?
Still, the bass can sometimes get kind of “stuffy.” Instead of being really crisp with good impact, it sometimes sounds loose and flabby, like it’s struggling to keep up. The reason for this is due to roll off. It really takes a nosedive after around 50-60Hz (somewhere in there).
The Mid-Range on the 598 is fantastic. It’s the best part about this headphones sound for sure. It’s relatively flat, and provides great vocal and instrument presence without sounding too forward. You never get a sense that the music is trying to force itself onto you. It feels natural and relaxed, while also feeling present and alive. If there were ever a headphone that could claim “balanced”, I think the 598 would fit the bill almost perfectly. There’s a small presence bump around 2k which sounds great and is just the right amount.
The treble here does have a bit of sparkle, but it’s done tastefully and doesn’t sound nearly as bright as something like a Samson SR850. That said, it is brighter than a 600 and 650, which is one of the main differences between the sound, along with the bass.
I kind of view that whole “veil” thing as kind of a myth, but I can see the 650 being more veiled for sure. In comparison to the 600, it’s even more relaxed, and has been accused of lulling you to sleep! Greg Mahler wrote a great article on Head-Fi about 58 headphones he demoed. The HD 600 was one of 4 that got an A+ rating. See:Battle of the Flagships – 58 Headphones Compared
The other difference between the HD 600 and the 598 is bass response. The 598’s rolls off quite a bit more, while the 600 sounds snappier and tighter.
The HD598 vs. 650’s bass?
Same type of thing. The 650’s will be tighter with more impact and less roll off.
The only difference between the bass of the 650 vs. the 600 is that the 650 has a tad more mid-bass emphasis, resulting in a bit of a warmer, more impactful response overall. It’s very pleasant actually!
The mid-range on the HD 598 is a bit different in that it does have a presence bump at 2k but it’s not over-exaggerated like that of the HD 600. The problem with the 600 is that the area around 2-3k is just too forward, and there’s too much presence. It doesn’t ruin the experience, but it’s a definite flaw and you will notice it sooner or later.
By contrast, the 650’s mid-range is a bit more similar to that of the 598. It’s toned back and sounds a lot more natural and organic. I much prefer the sound of the 650’s mid-range vs. that of the HD 600. It’s just a lot more tolerable over long listening sessions.
The 598 is similar in that regard; you won’t find yourself wanting to take the headphone off due to annoyance in those regions of 2-3k.
Lastly, the treble on the 598 is going to be much brighter than that of the 650. In fact, the 650’s treble is even more relaxed than the 600’s, as mentioned before. The 598 does have a peak around 9k, but it’s mostly going to be in line with the rest of the signature. You won’t really find it to be piercing or shrill.
The HD 650’s treble is extremely dark, but it’s really really fun and pleasant to listen to. I find myself wanting to put the 650 on my head more so than the others by a wide margin. It’s simply a better experience for the casual listener.
In a world where the majority of headphones out there have way too much treble, the HD 650 is a welcome deviation from that norm.
So to sum it up:
The HD600’s sound is forward in the mid-range, snappier, and crisper sounding.
The HD650’s sound is more laid back, more relaxed, and more smoothed over – sort of like sandpaper to wood.
The HD598’s sound is very balanced and neutral sounding, with a pretty rolled off bass and some sparkle in the treble.
At 50 Ohm and 112dB Sensitivity, the HD 598 won’t resist power too much and doesn’t require much from an amp to sound loud enough. I was running it with a JDS Labs Element and didn’t have to turn the dial much at all.
For this headphone, the maximum you’d need is something like an E10K, which provides 200mW into 32 Ohms. It’s a great desktop starter Amp/DAC and sounds really good.
At 300 Ohm and 97dB Sensitivity, the 600 will resist power fed into it and also requires a fair bit to reach acceptable listening levels. I wouldn’t purchase this headphone without also planning on investing in proper amplification. Fortunately, it doesn’t have to be complicated. For desktop I would go with a JDS Labs Objective 2 as it outputs plenty of power and sounds pristine.
I also love the 600 with an Audioquest DragonFly Red if you want something smaller and more portable. Truthfully, this headphone isn’t too picky about what you go with. It sounds good out of an E10K as well with the gain switch on and the volume at around 5-6.
Here’s a cool Shootout with 3 of my favorite Amp DACs including the DragonFly Red! Leave me some love if you found any of this helpful!
The HD 650 at 300 Ohm and 103dB of Sensitivity actually requires a bit less power from an amp to reach an acceptable listening level. I find that it’s not quite as difficult to achieve peak loudness because it’s a bit more efficient than an HD600.
For the 598, I’d mostly stick to lighter genres like Jazz, Classical, Acoustic, Folk, etc. I did listen to some Indie Pop, Rock, etc. and found it to be a mostly good experience, but that bass response is a little to lean for me to rely on it full time for bass heavier genres like Hip-Hop as well. It’s just going to sound fuzzy and distorted at times, mostly because the sub-bass is lacking quite a bit. You’re not going to achieve that slam and impact that you’re looking for with this headphone.
HD 600 & 650
With the HD 600, you will be able to comfortably play a lot of the genres that the 598 won’t work for, namely Indie Pop, Rock, Hip-Hop, etc. It’s been argued that Rock is the best overall genre for both the 600 and 650 and I can’t really argue with that. I think it has the perfect amount of bass for this genre, with a great amount of clarity and instrument separation.
I wouldn’t rely on either of these headphones for really crunchy guitars, or genres like Hard Rock and Metal. While it will still sound good, it’s going to lack the raw power and excitement that something like an HD25 provides in spades.
If you need a Gaming headphone, the 598 is definitely going to be a bit better than either a 600 or 650. I’d rank the 650 second as it really did surprise me in how well it handled gaming. It’s got a better Soundstage than an HD600, and better immerses you into the environment.
The 598 is even better, and is worthy of being your full time dedicated gaming headphone. The Soundstage here is also more open. Because the bass is lighter, you can better hear footsteps, as well as small, intricate details you might otherwise miss with the others.
I think the main takeaway here is to understand that the 650 is going to work better for more genres and also be more professional sounding than a 598. The 598 is by no means a bad headphone. I love it for Gaming, I love it for lighter genres, but it kind of loses me with the music that I most like to listen to. While it still works for those specific genres, it won’t sound as refined or clean. You will get some distortion at higher volumes as well.
The HD 600 has long been considered the Gold Standard, and for good reason. Though it’s mid-range has a tendency to get out of line at times, the headphone is nearly perfect otherwise, with great instrument separation, detail, and Timbre. It improves on what was lacking in the 598, and sounds a lot more refined and professional.
The HD 650 is currently my favorite among this crop, as it sounds more relaxed, more accessible, and more laid back in that all important 1-3k area. You’re not going to feel the urge to take the headphone off because vocals sound too forward, but you’re also not going to be bored with it. It’s an incredibly classy sound with enough impact to keep your attention. In fact, I think this is the quintessential audiophile headphone for folks who are new to the hobby and want to know what music is supposed to sound like. The 650 also has a bit more mid-bass emphasis and therefore will provide more impact for stuff like Hip-Hop and Indie Pop.
Some will dock points for the darker sounding treble, but I personally enjoy it. It’s still detailed but doesn’t sound shrill or harsh in the slightest.
Stu is determined to help you make sound decisions, and strives to deliver the best and most in depth content on the internet! In his spare time, he likes to fish, paint, play guitar, attend church, take photos, record videos, graphic design, and more. His strict attention to detail and perfectionist attitude are what allow him to excel and stand out among-st the crowd.