This is a review I've been putting off until I got my new amp the Schiit Lyr 2 mainly because I wanted to spend time with both headphones on a higher end system than what I had before. This review is my overall impressions of the two headphones and which I ultimately think is better on my system. It may be weird I'm comparing a mid-tier closed-back vs a mid-tier open-back but there is a good reason for this as will come to light throughout the review. Both headphones scale up very well I personally believe both are in the same league. The main system used is the Schiit Lyr 2(stock tubes 6BZ7 Canada) as the amp with the HRT Music Streamer II+ as the DAC. There will be some changes/updates to this review as time passes, as I gain more experience, and after gear changes.


Build Quality and Comfort:
AKG K712 Pro: This is a well made headphone, everything is put well together and the plastic is of high quality, while there are no metal in the headphone, though the headband is leather I don't think this headphone is going to have any reliability issues. I have no complaints about the build quality of the headphone, they are built to last. Comfort wise I think they are among the most comfortable headphones I've owned, I have a lot of issues with comfort on headphones and these are one of the few that have passed the test, the headband just disappears. The memory foam velour pads are very comfy and are not scratchy at all which can be the case with some velour pads. Earpads are very deep, people who worry about ears touching drivers shouldn't have any issues with these headphones. These headphone have a moderate clamp. Although some reason after a few hours, I feel the earcups move around a bit and this ultimately causes some discomfort at times and leads to some readjustment.
Beyerdynamic DT 150: The build quality on these headphones is simply fantastic, it has some of the most robust and toughest plastic I've ever seen used as the earcup housing, the headband is metal, despite the robust build these headphones are lightweight, they actually weigh about the same as the AKGs. Something odd to note about these headphones is the cable comes out of the right side instead of left side. The cable also has a small flat-head screw that probably should be screwed in to help the cable stay in better. The pads are made of a synthetic leather and the headband is also covered with a synthetic leather. I have no issue with the headband and the pads are very deep, deeper than the AKGs pads. They do get a bit hot and sweaty at times but not too bad. The adjustment mechanism of the earcups sliding up and down the metal band takes some getting used to. Also these headphones need a week or two for the pads to form to your head otherwise comfort and seal may be iffy. These headphones clamp a little more than the AKGs. Overall and oddly I find these headphones more comfortable than the AKGs in long listening sessions. But I found comfort a mix.
Build Quality: Beyerdynamic DT 150
Comfort: Tie(depends)
Sound:
Now it's time to cover the sound of these headphones, I'm doing an overall review of the headphones sound on my system, not really covering any particular song or album but rather how they perform across the board, how they respond to a variety of genres, how they handle lesser recordings, which is more enjoyable to listen to, and ultimately which I find is the overall superior sounding headphone on my system. Both headphones are on the warm and darker side of the spectrum and I wouldn't call either bright or cold by any stretch.
Soundstage and Imaging:
AKG K712 Pro: Soundstage and imaging is one of this headphones strong points. It has a nice wide soundstage that has precise and accurate position of instruments. It can have a slightly distant nature to it, other times it can be oddly forward. It's one of the bigger soundstages I've heard in an headphone, but it is a revision of a soundstage oriented headphone. I found the soundstage quite natural and pleasing. I'm not really the best at describing soundstage as it's generally not an aspect I tend to focus too much on but it's something I like to have.
Beyerdynamic DT 150: This headphone surprised me by how open and spacious sounding it sounded. It's not a large or huge soundstage, but rather a more medium and round soundstage, it is bigger than some open-backs I've heard. Imaging is where this headphone shines, it's very clean. There is absolutely no closed-back honkiness to be found on this headphone. This headphone has a black background so each instrument is easily discernible.
Soundstage(Lyr 2 Stock Tubes): AKG K712 Pro
Imaging Precision(Lyr 2 Stock Tubes): AKG K712 Pro
Imaging Cleanness(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Transparency and Detail:
AKG K712 Pro: I found this headphone quite transparent but to be honest I've found the background a bit hazy at times(I'm quite sure it's synergy issues with my system from past experience, the Lyr 2's stock tubes don't seem to be that good of a pairing with the K712), this headphone doesn't have as black of a background as the DT 150 and at times isn't as easy to discern details as the DT 150. Although this headphone does seem to have a good amount of detail and seems to be quite fast and resolves a lot of information. I would say it's just a little more detailed overall and a little faster than the DT 150.
Beyerdynamic DT 150: This headphone is very transparent and has great macro-detail, everything is clear and easily discernible. I found this headphone faster side, it never has trouble with any music no matter how complex and reveals all the detail and information without issue.
Transparency(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Background(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Detail(Lyr 2 Stock Tubes): AKG K712 Pro
Speed(Lyr 2 Stock Tubes): AKG K712 Pro
Bass:
AKG K712 Pro: This is one aspect where this headphone really shines, especially with a beefy amp behind it. It goes very deep and is very well-controlled, clean, textured, and articulate. It's very natural sounding and can vary a bit in terms of impact. It has a bit of a mid-bass emphasis which is a nice touch and on occasion the bass seems stronger than the DT 150s for some reason.
Beyerdynamic DT 150: This headphone also has good bass, it's very impactful and quite punchy while staying controlled and never getting muddy though it can get a bit boomy at times. It's not quite as tight and textured as the AKGs bass though it stills sounds natural and it's overall stronger bass leads it to sounding better in terms of bass on more songs. It doesn't go quite as deep as the K712's bass. It also gives it's overall sound more of a backbone and solidity than that of the AKGs. This leads to an amazing headphone for anything needing a strong punchy bass-line or those songs with a relatively weak bass-line. It's a fun and enjoyable bass. While the bass does sound quite natural overall it can be a tad strong at times and isn't quite as natural sounding as the AKGs bass.
Bass(Lyr 2 Stock Tubes): AKG K712 Pro
Midrange:
AKG K712 Pro: I found the midrange on this headphone quite articulate and detailed with a slightly warm and musical tone to it. I don't really find it forward or recessed in my experience. Vocals are nice with plenty of musical depth. There does seem to be a bit of a boost in the 2khz region which can make the headphone a bit hard and overly forward on some vocals and instruments and ultimately takes away from some of it's transparency and naturalness.
Beyerdynamic DT 150: This is where this headphone shines, extremely clear, natural, and musical. This headphone has some of the best vocals and midrange of the headphones I have owned. The midrange is a little more laid-back than the AKGs, largely due to the K712s 2khz boost. The midrange is darker but also a tad less warm than the K712's, the DT 150s mids are on the lush side. Actually the whole sound is a bit lush on the DT 150. The very clean and natural midrange makes this headphone win in this category overall.
Midrange(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Treble:
AKG K712 Pro: This headphone has well-extended and smooth treble, not harsh or sibilant at all on more powerful systems. It seems to extend quite well and overall is on the darker side overall, the lower treble is a bit brighter than the DT 150s. The treble can sound harsh on less powerful systems or systems with bad synergy.
Beyerdynamic DT 150: This headphone has very clean and transparent treble with good extension. Overall I find this headphones upper treble a bit brighter(a slight Beyer-peak) but still very smooth and grain-free. The treble seems a little cleaner on DT 150 overall.
Treble(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Conclusion:
Pesonally I have to give the slight edge to the Beyerdynamic DT 150 as being a little better at least on the system I compared the two on, this was actually very close and a hard choice. Which I think is better may change as with system changes and/or upgrades, but as of now I respect the DT 150 more because it's a closed-back and my slight preference towards it. These are my two favorite headphones and I wouldn't really be able to part with either one. Overall I find both headphones to handle a wide variety of genres excellently, I haven't really found a genre either headphones sounds bad at. These are both excellent all-rounders. It is entirely possible I will switch back and forth between which I like better for a long time to come. It's the first time I experienced headphones that are so close in sound preference and quality I can't whole-heartily say one is better than the other. These are very different sounding headphones. The DT 150 is a rather unique sounding headphone, I haven't really heard anything like it before. The K712 has that AKG house sound to it.
I have found the Beyerdynamic DT 150 to relatively retain its general sound signature no matter what they are plugged into, they are quite forgiving of the system but they do scale up very well with better gear. The AKG K712 Pro on the other is all over the place in it's sound signature and characteristics depending on the system compared to the DT 150. I've never owned a headphone that changed as much sonically from one system to another as the K712. Simple things such as changing tubes, amps, dacs, etc. can completely change the K712s sound. The K712s pretty much sound like what they are plugged into. This leads me to believe the K712 may have more potential in the end than the DT 150 or that it's simply a very picky headphone.
I think the DT 150 should be considered among the best mid-tier headphones out there and people should really give this ignored and honestly somewhat ugly headphone a chance, especially those looking for a closed-back. It's sound is something truly special and deserves more attention than it gets.
Build Quality and Comfort:
AKG K712 Pro: This is a well made headphone, everything is put well together and the plastic is of high quality, while there are no metal in the headphone, though the headband is leather I don't think this headphone is going to have any reliability issues. I have no complaints about the build quality of the headphone, they are built to last. Comfort wise I think they are among the most comfortable headphones I've owned, I have a lot of issues with comfort on headphones and these are one of the few that have passed the test, the headband just disappears. The memory foam velour pads are very comfy and are not scratchy at all which can be the case with some velour pads. Earpads are very deep, people who worry about ears touching drivers shouldn't have any issues with these headphones. These headphone have a moderate clamp. Although some reason after a few hours, I feel the earcups move around a bit and this ultimately causes some discomfort at times and leads to some readjustment.
Beyerdynamic DT 150: The build quality on these headphones is simply fantastic, it has some of the most robust and toughest plastic I've ever seen used as the earcup housing, the headband is metal, despite the robust build these headphones are lightweight, they actually weigh about the same as the AKGs. Something odd to note about these headphones is the cable comes out of the right side instead of left side. The cable also has a small flat-head screw that probably should be screwed in to help the cable stay in better. The pads are made of a synthetic leather and the headband is also covered with a synthetic leather. I have no issue with the headband and the pads are very deep, deeper than the AKGs pads. They do get a bit hot and sweaty at times but not too bad. The adjustment mechanism of the earcups sliding up and down the metal band takes some getting used to. Also these headphones need a week or two for the pads to form to your head otherwise comfort and seal may be iffy. These headphones clamp a little more than the AKGs. Overall and oddly I find these headphones more comfortable than the AKGs in long listening sessions. But I found comfort a mix.
Build Quality: Beyerdynamic DT 150
Comfort: Tie(depends)
Sound:
Now it's time to cover the sound of these headphones, I'm doing an overall review of the headphones sound on my system, not really covering any particular song or album but rather how they perform across the board, how they respond to a variety of genres, how they handle lesser recordings, which is more enjoyable to listen to, and ultimately which I find is the overall superior sounding headphone on my system. Both headphones are on the warm and darker side of the spectrum and I wouldn't call either bright or cold by any stretch.
Soundstage and Imaging:
AKG K712 Pro: Soundstage and imaging is one of this headphones strong points. It has a nice wide soundstage that has precise and accurate position of instruments. It can have a slightly distant nature to it, other times it can be oddly forward. It's one of the bigger soundstages I've heard in an headphone, but it is a revision of a soundstage oriented headphone. I found the soundstage quite natural and pleasing. I'm not really the best at describing soundstage as it's generally not an aspect I tend to focus too much on but it's something I like to have.
Beyerdynamic DT 150: This headphone surprised me by how open and spacious sounding it sounded. It's not a large or huge soundstage, but rather a more medium and round soundstage, it is bigger than some open-backs I've heard. Imaging is where this headphone shines, it's very clean. There is absolutely no closed-back honkiness to be found on this headphone. This headphone has a black background so each instrument is easily discernible.
Soundstage(Lyr 2 Stock Tubes): AKG K712 Pro
Imaging Precision(Lyr 2 Stock Tubes): AKG K712 Pro
Imaging Cleanness(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Transparency and Detail:
AKG K712 Pro: I found this headphone quite transparent but to be honest I've found the background a bit hazy at times(I'm quite sure it's synergy issues with my system from past experience, the Lyr 2's stock tubes don't seem to be that good of a pairing with the K712), this headphone doesn't have as black of a background as the DT 150 and at times isn't as easy to discern details as the DT 150. Although this headphone does seem to have a good amount of detail and seems to be quite fast and resolves a lot of information. I would say it's just a little more detailed overall and a little faster than the DT 150.
Beyerdynamic DT 150: This headphone is very transparent and has great macro-detail, everything is clear and easily discernible. I found this headphone faster side, it never has trouble with any music no matter how complex and reveals all the detail and information without issue.
Transparency(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Background(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Detail(Lyr 2 Stock Tubes): AKG K712 Pro
Speed(Lyr 2 Stock Tubes): AKG K712 Pro
Bass:
AKG K712 Pro: This is one aspect where this headphone really shines, especially with a beefy amp behind it. It goes very deep and is very well-controlled, clean, textured, and articulate. It's very natural sounding and can vary a bit in terms of impact. It has a bit of a mid-bass emphasis which is a nice touch and on occasion the bass seems stronger than the DT 150s for some reason.
Beyerdynamic DT 150: This headphone also has good bass, it's very impactful and quite punchy while staying controlled and never getting muddy though it can get a bit boomy at times. It's not quite as tight and textured as the AKGs bass though it stills sounds natural and it's overall stronger bass leads it to sounding better in terms of bass on more songs. It doesn't go quite as deep as the K712's bass. It also gives it's overall sound more of a backbone and solidity than that of the AKGs. This leads to an amazing headphone for anything needing a strong punchy bass-line or those songs with a relatively weak bass-line. It's a fun and enjoyable bass. While the bass does sound quite natural overall it can be a tad strong at times and isn't quite as natural sounding as the AKGs bass.
Bass(Lyr 2 Stock Tubes): AKG K712 Pro
Midrange:
AKG K712 Pro: I found the midrange on this headphone quite articulate and detailed with a slightly warm and musical tone to it. I don't really find it forward or recessed in my experience. Vocals are nice with plenty of musical depth. There does seem to be a bit of a boost in the 2khz region which can make the headphone a bit hard and overly forward on some vocals and instruments and ultimately takes away from some of it's transparency and naturalness.
Beyerdynamic DT 150: This is where this headphone shines, extremely clear, natural, and musical. This headphone has some of the best vocals and midrange of the headphones I have owned. The midrange is a little more laid-back than the AKGs, largely due to the K712s 2khz boost. The midrange is darker but also a tad less warm than the K712's, the DT 150s mids are on the lush side. Actually the whole sound is a bit lush on the DT 150. The very clean and natural midrange makes this headphone win in this category overall.
Midrange(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Treble:
AKG K712 Pro: This headphone has well-extended and smooth treble, not harsh or sibilant at all on more powerful systems. It seems to extend quite well and overall is on the darker side overall, the lower treble is a bit brighter than the DT 150s. The treble can sound harsh on less powerful systems or systems with bad synergy.
Beyerdynamic DT 150: This headphone has very clean and transparent treble with good extension. Overall I find this headphones upper treble a bit brighter(a slight Beyer-peak) but still very smooth and grain-free. The treble seems a little cleaner on DT 150 overall.
Treble(Lyr 2 Stock Tubes): Beyerdynamic DT 150
Conclusion:
Pesonally I have to give the slight edge to the Beyerdynamic DT 150 as being a little better at least on the system I compared the two on, this was actually very close and a hard choice. Which I think is better may change as with system changes and/or upgrades, but as of now I respect the DT 150 more because it's a closed-back and my slight preference towards it. These are my two favorite headphones and I wouldn't really be able to part with either one. Overall I find both headphones to handle a wide variety of genres excellently, I haven't really found a genre either headphones sounds bad at. These are both excellent all-rounders. It is entirely possible I will switch back and forth between which I like better for a long time to come. It's the first time I experienced headphones that are so close in sound preference and quality I can't whole-heartily say one is better than the other. These are very different sounding headphones. The DT 150 is a rather unique sounding headphone, I haven't really heard anything like it before. The K712 has that AKG house sound to it.
I have found the Beyerdynamic DT 150 to relatively retain its general sound signature no matter what they are plugged into, they are quite forgiving of the system but they do scale up very well with better gear. The AKG K712 Pro on the other is all over the place in it's sound signature and characteristics depending on the system compared to the DT 150. I've never owned a headphone that changed as much sonically from one system to another as the K712. Simple things such as changing tubes, amps, dacs, etc. can completely change the K712s sound. The K712s pretty much sound like what they are plugged into. This leads me to believe the K712 may have more potential in the end than the DT 150 or that it's simply a very picky headphone.
I think the DT 150 should be considered among the best mid-tier headphones out there and people should really give this ignored and honestly somewhat ugly headphone a chance, especially those looking for a closed-back. It's sound is something truly special and deserves more attention than it gets.