Reviews by BigBadBirdman

I bought the Grado SR80e but I was not too happy with it. After a month, I was hardly ever using it. I also own the Sennheiser HD600 and HD700, Beyerdynamic DT990 and T51i, Massdrop HifiMan HE4xx, and Philips Fidelio X2. All my other headphones sounded better than the Grado.

I use the Schitt Asgard 2 for my amp and a Marantz CD5005 as the source.

The problem is the Grado was way too bright and it only had a hint of bass. I normally listen to headphones at low to moderate volumes but the Grado only sounds good when it is played loud. When I tried to play the Grado loud, it would hurt my ears due to the bright treble. When played at moderate volume, it would lack bass and have too much treble.

First, I tried swapping pads. I bought the replacement pad for the Sennheiser HD414 (the bright yellow pads.) It was essentially the same as the stock pads as far as sound and comfort, so it did not help at all. It seemed to me the problem was that the drivers were too close to my ears, so I stacked the original pads on top of the new pads, so it was now double the distance to my ears. This reduced the volume considerably, so I had to crank it up.

The result was that now the frequency response is smoothed out quite a bit (but still some brightness,) the bass is much fuller, and the separation of instruments is the best I have heard.

I listen almost exclusively to classical and opera. With the double pads the Grado SR80e is as good as any of my other headphones and on some recordings, it is the best.

If you are thinking of purchasing the Grado SR80e, I recommend picking up an extra set of pads and trying the double pad mod. Just make sure you have an amp that is powerful enough to make up for the extra volume you will need to accommodate the loss of efficiency.

For me, it made all the difference in the world. I would hardly ever use the Grado when I was using the stock pads by themselves. With the double pad mod, they are often times my favorite headphones.

Treble - Before mod, treble was very bright and harsh. With mod, treble is well integrated with the rest of the frequencies.

Midrange - Before mod, lower midrange was almost missing completely and upper midrange was bright and harsh. After the mod, midrange has exceptional clarity.

Bass - Before mod, bass was mostly missing or very faint on most recordings. In fact I was mostly using the Grado only on recordings that had too much bass. After the mod, the bass is really detailed and extended and it is well integrated with the rest of the frequencies. The Grado has the best bass of any of my headphones except for the X2.

Imaging and soundstage - Before the mod, imaging was pretty good but not as good as the HD700 or HE4xx. Soundstage was barely there. After the mod, imaging and soundstage are better than any of the other headphones I own.

I recommend doing the double-pad mod if you already own the Grado SR80e. I do not think I will ever listen to them without it. It completely transforms the listening experience.

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I just changed to a cheap knockoff of the G Cushion for the top pad. It makes the SR80e much more comfortable and gives a big boost to the bass and smooths out the treble. I highly recommend using the G Cushion for the pad that you put on your ear.

Besides the Massdrop X Hifiman HE 4XX, my other headphones are the Sennheiser HD600 and HD700, Beyerdynamic dt990, and Philips Fidelio X2. Each of these headphones could be considered my favorite on any given day. I swap headphones to match with specific recordings. I use the Schitt Asgard 2 for the headphone amp and the Marantz CD5005 as the source. I listen mostly to classical and opera.

The Hifiman HE 4XX is my second headphone purchase from Hifiman. I previously owned the HE 400S but I returned it (and paid a hefty restocking fee) because it had little or no bass, poor treble extension, and poor resolution.

The HE 4XX sounded significantly better than the HE 400S right out of the box. It has a warm, full bass and smooth midrange but the resolution was poor and the imaging was the worst of any headphone I have ever owned. There was no imaging or soundstage whatsoever.

I burned them in for about 700 hours but there was no improvement in resolution or imaging, so I started looking for mods and found that some people like to replace the outer grill. I removed the grill on the right ear cup and found that 2 of the ribbons had paper glued to them. I removed the paper and glue the best I could. I also removed the cloth filter from the grill before replacing it. Then I removed the grill from the left ear cup and found that 3 of the ribbons had paper and glue on them. I removed it the best I could and replaced the grill after removing the cloth filter.

After doing the repair, the sound immediately and dramatically improved. The resolution and detail went from poor to good and imaging and soundstage went from non-existent to excellent.

Sound

Before the repair, the Massdrop X Hifiman HE 4XX had a mainstream friendly sound. It had a warm sound but poor detail. The texture of the sound that I normally hear from my other headphones was noticeably missing. I had trouble finding recordings that I could listen to and would frequently have to change to a different headphone part way through the first track. There was no imaging or soundstage. I imagine that some people would not notice this problem and they would think there was nothing wrong with the defective headphones.

After the repair, the Massdrop X Hifiman HE 4XX sounded much different. Resolution and soundstage had a huge improvement. However, I was still not in love with them. It was hard finding recordings that sounded good on these headphones. Compared to my other headphones, the sound was muddy in the bass and the treble was too rolled off.

Then one night I was listening to the Emerson String Quartet CD of Bach Fugues and I could not get it to sound good. It sounded really muddy and congested. Then I lowered the volume a bit and it sounded a little better. Eventually I lowered the volume so much that it was like I was listening to background music but the sound was much clearer and enjoyable.

These days I mostly use the HE 4XX mostly for late night, low volume listening for chamber music. None of my other headphones can be played at such low volumes without the soundstage and tonal quality collapsing. The HE 4XX fills a niche that my other headphones cannot fulfill.

Bass 4/5

Before the repair, the Massdrop X Hifiman HE 4XX had a big, fat, upper bass and lower midrange but not much extension. It was like listening to a car stereo with a 4 inch woofer and the bass boosted by an equalizer.

After the repair, the Massdrop X Hifiman HE 4XX has much better bass extension and texture. It now extends an octave or two lower but lacks the slam and sub-bass rumbles of larger and more expensive headphones but most people will probably not notice this unless they are listening to orchestral music and they have been using other headphones with better extension.

Midrange 4/5

The Massdrop X Hifiman HE 4XX has a smooth midrange that lacks some detail on some recordings. There was not much change in tonal quality to the midrange after the repair. Compared to my other headphones, the HE 4XX has a warm lower midrange that obscures some detail but gives the music a more natural tonal balance on some recordings.

Treble 4/5

The Massdrop X Hifiman HE 4XX has the least detailed and extended treble of any of my headphones but that is not necessarily a bad thing. Recordings with a bright or strident treble sound better on the HE 4XX than on my other headphones, so the HE 4XX actually fills a void in my headphone collection by having a more forgiving treble balance.

Imaging and Soundstage 5/5

Before I repaired the ribbons, the HE 4XX had no imaging or soundstage at all. I actually thought that one of the ear cups might have been wired out of phase. After the repair, it became one of the best imaging headphones. Only the HD700 images better.

Comfort 4/5

The ear cups are large and some people might have trouble getting a good seal or finding a comfortable position on their head. Also, they tend to grip the frames of my glasses. Other than that, they are fairly comfortable although they are a bit on the heavy side.

Quality Control 1/5

The first run of the Massdrop X Hifiman HE 4XX had a lot of complaints about the yoke that holds the ear cups to the head band coming off. The only reason I bought these was that there were not any recent complaints, so I figured the problem was fixed. The problem with the tape on the ribbons is actually a worse problem in my opinion because most people who own this headphone most likely have not taken off the grills to check for any defects.

Quality control this bad is not acceptable. I will not buy another Hifiman product until they resolve their QC and build quality issues. Even though I was able to repair these to the point where they sound good I am not confident they will last very long. Until quality control becomes comparable to the other headphone manufacturers, I consider Hifiman products to be disposable and they will probably break shortly after the 1 year warranty expires.

Overall 1/5

The Massdrop X Hifiman HE 4XX would have gotten a 4/5 score if I had received a non-defective unit. I cannot recommend a headphone that was shipped to me defective and I cannot recommend buying from a manufacturer that has shipped me 2 defective headphones. If you buy these, you are taking a risk. Despite the fact that I actually like the sound quality for the most part, I cannot recommend buying these or any other products from Hifiman.

Listening and Comparisons:

Tchaikovsky - Symphony #1 “Winter Dreams” by the Berlin Philharmonic, conducted by Herbert von Karajan – This was the last recording I listened to before I found out my HE 4XX was defective. The tonal quality was fine but there was no imaging or soundstage. It was almost like listening to a mono recording. About halfway through the first movement, I switched to the Fidelio X2 and the difference was astounding. The X2 has a huge soundstage and about 2 more octaves in the bass and treble regions. Once I repaired the HE 4XX, I listened again and there was a big improvement but overall, I prefer the X2 over the HE 4XX for this recording.

Bach – Goldberg Variations played by Murray Perahia – I have had this recording for years and never really warmed to it. I have many other versions of this work that I listen to more often. But when I listened at very low volume with the HE 4XX, I could hear all kinds of nuances that were obscured by other headphones. This is the main strength of these headphones: They can play at a much lower volume than my other headphones without losing the soundstage and tonal balance.

Handel – Rinaldo played by the Freiburger Barockorchester conducted by Rene Jacobs – This is one of my favorite recordings but it has always sounded a bit on the lean side. With the HE 4XX, there is some added warmth and it smooths out the treble which can sound a bit harsh. I usually use the HD700 for this recording but the HE 4XX holds up well against the competition.

Beethoven – Symphony #8 played by the Cleveland Orchestra conducted by George Szell – This recording sounded real muddy on the HE 4XX, even when I tried adjusting the volume. I tried high volume and low volume but neither helped with the lack of clarity. This recording sounds much better on the HD600 or dt990.

Mahler – Symphony #3 played by the Boston Symphony conducted by Erik Leinsdorf. This is on the High Performance series of recordings and on my other headphones it is one of the best sounding orchestral recordings I have heard. The weight of the bass and the detail in the treble make it sound like a live performance. However, the HE 4XX was not able to reproduce the fantastic sound that I get from all my other headphones. The X2 is the one I use most of the time for this one. The HE 4XX sounds flat and dull in comparison.

Conclusion

I am sorry to say that I cannot recommend anyone buying the Massdrop X Hifiman HE 4XX or any product from Hifiman due to their non-existent quality control. Mine had paper glued on both ribbon drivers, so I have to assume that all the drivers are defective. If you already own these, I recommend removing the grill covers and checking the ribbons. Even after I removed the paper, these do not sound as detailed and dynamic as my other headphones.

However, they are more forgiving of poor quality recordings than my other headphones and they sound better at low volumes than my other headphones, so they fill a niche in my headphone collection. Once I repaired the ribbons, they image as good or better than my other headphones and have a deep soundstage. The perspective is more like you are sitting on the first tier or rear orchestra. All my other headphones give a perspective more like front row center.


At $169.99 plus tax, the Massdrop X Hifiman HE 4XX represents a fair value if you are able to get a non-defective unit. My Beyerdynamic dt-990 was only $129 and the Philips Fidelio X2 was $200 and both are much better sounding headphones in my opinion. My Sennheisers both sound better than the HE 4XX but they are more expensive.

Buyer beware: Purchase at your own risk. You will most likely get a defective headphone if you buy these.

(The photo was taken with the grill cloth removed.)

Introduction

The Audio Technica ATH-MSR7 is a bright sounding headphone that will not appeal to people who want a warm or neutral sound.

Sound Signature

The SR stands for Sound Reality but the sound is not realistic at all if you ever go to classical music concerts. I have been to hundreds of concerts and every time I am impressed at how big and warm the sound is. The sound in every concert hall I have been in has a huge bass that cannot be reproduced accurately by any speaker and headphone. The Audio Technica ATH-MSR7 does not even try. Instead, they try to pass themselves off as “high resolution” by decreasing the upper bass and lower midrange and increasing the upper midrange and lower treble. By doing this you will hear some things that you will not hear in a neutral or warm sounding headphone but you are also missing much of your music.

When listening to “El amor brujo” conducted by Leopold Stokowski, the sound was very strange. It was like listening to tiny speakers with a subwoofer. The bass is deep and extended but there is no upper bass or lower midrange and the upper midrange is super loud. When I play this recording on any of my other headphones, the sound is warm and smooth.

Next I put on Beethoven’s Eighth Symphony conducted by George Szell and got the same results. There was a thinness to the sound that is completely unnatural. You would never hear a tonal balance like this in any concert hall. I have had this CD for decades and listened to it on many different speakers and headphones and it is normally a warm sounding recording. The Audio Technica ATH-MSR7 just sucked the life out of the performance.

“The Rite of Spring” conducted by Simon Rattle actually sounded pretty good. There was really good resolution in the quiet parts and the big bass drum whacks had depth and power.

Probably the most disappointing recording was the Mahler First conducted by Erich Leinsdorf. This is one of my reference recordings and on the Philips X2 it is one of the most lifelike sounding recordings I have. On the ATH-MSR7, the sound was thin and anemic and generally unpleasant. I only made it about halfway through the first movement before I had to change to a different headphone.

My Setup

I use CD, Blu-ray, and DVD as my sound source. I mostly use a Marantz CD6005 but sometimes use an Onkyo C-7030 as my CD player. I use a cheap Sony Blu-ray player for video.

I drive all my headphones with a Schiit Asgard 2 headphone amplifier. The Audio Technica ATH-MSR7 is designed for portable use. However, I do not use any portable listening devices and do all my listening exclusively at home.

If you are planning on purchasing the Audio Technica ATH-MSR7 and you intend to use them on your home audio system, you will need to purchase a 1/8” to 1/4” adaptor. There are 3 cables supplied but they all are 1/8” and there is no adaptor included. All my other headphones came with adaptors but apparently Audio Technica thinks the ATH-MSR7 is only going to be used with portable players.

I primarily listen to opera and orchestral music. The other headphones I currently own are the Sennheiser HD600, Sennheiser HD700, Beyerdynamic DT-990, Beyerdynamic T51i, and Philips Fidelio X2. All my headphones sound amazingly good when paired with the appropriate recording and each can be the best headphone I have ever heard. I consider all of my headphones to be a good value for the price.

The Highs

The treble on Audio Technica ATH-MSR7 is loud. It is louder than any of my other headphones but not necessarily more detailed. While other headphones might have a boost in the mid or upper treble, the ATH-MSR7 starts the boost in the upper midrange and through the lower treble. Because of that you cannot really hear anything above the lower treble because it is drowned out by the volume.

The quality of the treble is middling. It is on par with the DT-990 and X2 but not as good as the HD600, HD700 or T51i.

The Midrange

The midrange is the most problematic part of the ATH-MSR7. The lean lower midrange coupled with the bright upper midrange is the downfall with this headphone. If they had gotten the midrange right, I think I might have been able to overlook the loud treble.

The Bass

The bass is the best aspect of the ATH-MSR7. It is very detailed and extended and neutral. There is no bloat but it is powerful when needed. The big bass drums on Tchaikovsky and Stravinsky had excellent detail and impact. On Handel’s Serse, the bass was big and warm. Unfortunately the upper bass starts to disappear and it makes Beethoven and Haydn symphonies sound too lean.

Soundstage

The ATH-MSR7 does not have much of a soundstage but it images pretty good. There is good separation of images but no depth. Closed back headphones generally do not have as good of a soundstage as open backed ones but my only closed back headphone is the T51i and it has a decent soundstage. The ATH-MSR7 is average or slightly above average in this category for a closed back design.

Conclusion

In head to head comparisons to my other 5 headphones, it usually came in dead last and it never came in first. The highest it ever ranked was 3. I think the problem is that Audio Technica is trying to market this headphone as “high resolution” but they are not using upgraded drivers so they are altering the frequency balance to give the illusion of having a higher resolution.

Introduction

The Sennheiser HD700 is a controversial headphone. It is the most expensive headphone I own and in many ways, it is my favorite. Others do not like it at all.

The main problem for me is the sound changes depending on how it is situated on my head. When I bought the HD700, it sounded muddy. After 3 weeks of trying to burn it in I was on verge of returning it for a refund. I decided to give it one last try and found that if I removed my glasses and moved the ear cups back and pressed them inward, the sound dramatically changed. Suddenly the sound became crystal clear and it had the best soundstage I have ever heard from a headphone.

There have been many reviews of the HD700 and nobody else has had the problems I have, so maybe there is a chance I got a defective unit since I bought it used.

I use the HD700 primarily for opera, choral and large orchestral. I have 5 other headphones and I use others when listening to small orchestral, chamber, or solo piano.

My Setup

I use CD, Blu-ray, and DVD as my sound source. I mostly use a Marantz CD6005 but sometimes use an Onkyo C-7030 as my CD player. I use a cheap Sony Blu-ray player for video.

I drive all my headphones with a Schiit Asgard 2 headphone amplifier. However, when I purchased the HD700 I was using the headphone jack from my CD player and it sounded fine.

The HD700 is designed for home use. I do not use any portable listening devices and do all my listening exclusively at home.

I primarily listen to opera and orchestral music. The other headphones I currently own are the Sennheiser HD600, Audio Technica ATH-MSR7, Beyerdynamic DT-990, Beyerdynamic T51i, and Philips Fidelio X2.

My speakers are the Apogee Centaurs driven by an old Carver solid state amp and a passive preamp. I live in a small condo, so I cannot play my music very loud without disturbing the neighbors. I do most of my music listening with headphones and use the speakers for movies and television.

Sound Quality

I would characterize the HD700 as a warm sounding headphone. It has more upper bass and lower midrange than my other headphones. This can be a problem on some recordings but it can make a big improvement on others.

The biggest flaw with the HD700 is that the sound changes with ear cup placement. With all my other headphones, you can just put them on your head and listen. With the HD700, I have to jiggle them around, push down on the ear cups, and move them around some more. Small adjustments to the ear cups make a huge difference in the sound quality. Since I wear glasses, this makes getting the best sound from the HD700 even more of a challenge. Sometimes it can take me a while to find the ideal position.

I notice that nobody else has remarked on having problems with ear cup placement being such an issue, so maybe it is a problem with my particular unit.

The Highs

I find the treble on the HD700 to be one of its best qualities. It is detailed and well extended. I have found a few recordings where the highs sound harsh but that is something I attribute to the recording, not the headphones. Some of the older reviews for the HD700 complained about the treble quality but I have not had any problems with it. I find the treble is well extended but not overly prominent. In fact, the treble volume is lower and less harsh than my Beyerdynamic DT-990, Audio Technica ATH-MSR7 and Philips X2.

The Midrange

The midrange is smooth and warm. On some recordings the midrange can sound muddy due to too much warmth. On other recordings, it sounds just right.

Most headphones I own have a big dip in the lower midrange and upper bass that accentuates the upper midrange. The HD700 does not have that dip. The warmth of the midrange can make some recordings that sound harsh on other headphones sound lush. On the other hand, some recordings with too much lower midrange can end up sounding a bit muddy.

On Stravinsky’s Pulcinella conducted by Pierre Boulez, the sound was real grainy on my HD600, DT-990, and X2. Changing to the HD700 completely transformed this recording to a lifelike concert experience.

The Bass

The bass if full, extended, and warm. It does not have the big impact of the X2 but it is more detailed and textured. When I listen to the video of Giulio Cesare conducted by William Christie, the lower strings sound fantastic. It sounds like sitting right in front of the orchestra pit.

On the Mozart Requiem conducted by William Christie, the bass was thin and anemic on the HD600. When I switched over to the HD700, it was big. It was like I was sitting in the front row of the concert hall. It entirely transformed the sound of this recording.

Soundstage

On some recordings, if you have the headphones just right and the volume set correctly, you can get the best soundstage I have ever heard from headphones. On the Giulio Cesare video, you can actually hear that the orchestra is in the pit and the singers are on the stage.

On the Ariodante recording conducted by Alan Curtis, you are surrounded by the orchestra as if you are on the podium and the singers are in front and above. You can hear every instrument in the orchestra and they sound like they are all coming from a separate location. You can hear the texture of the instruments, especially the lower strings.

Conclusion

The Sennheiser HD700 is the most expensive headphone I own. I purchased it for $400 “used” from Amazon Warehouse Deals in January of 2016 and there are many excellent headphones available at or below this price point.

At its best, it is the best sounding headphone I have heard but it is also the most frustrating. It can be very hard to get it to sound its best. I need to get the ear cups positioned just right and the volume setting needs to be precise. If the volume is too loud, the soundstage collapses.

The HD700 is pretty comfortable but I prefer the HD600 and DT-990 for comfort. The HD700 sounds best with a good seal and wearing glasses compromises the seal which makes it more difficult to get good sound. However, the HD700 is the headphone I use for the majority of my Blu-ray opera recordings, so it is work the effort as far as I’m concerned.

The Sennheiser HD700 is the fussiest headphone I own but under the right conditions it can be the most rewarding.

*********Addendum 4/30/19

I have come across a modification for the HD700 that addresses the problem I have when wearing eyeglasses. Simply replace the stock earpads with the Grado G Cushion (aka "salad bowls") or an aftermarket knockoff.

I find that this not only makes listening with eyeglasses more comfortable, but it also improves the sound stage and imaging. If you own the HD700 and have had some of the problems I have mentioned, you might give it a try.

Actually, I recommend replacing the stock pads with the G Cushion even if you don't wear glasses. It really opens up the soundstage and it makes the HD700 more comfortable. Be advised, you will lose a lot of sound pressure, so you will need to turn up the volume and you will need to have a powerful amp.

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Introduction

The Sennheiser HD600 is generally considered the reference headphone for Classical music and opera. I have owned mine for 17 years. I have purchased 5 other headphones since then but I still use my HD600 on a weekly basis and it is still one of my favorites.

The Sennheiser HD600 is considered a neutral headphone. It will sound like whatever your recordings sound like; for better or for worse. The reason that I have 5 other headphones is that not all recordings sound perfect and many recordings benefit from bass and treble boost. But on the occasion that I have a recording that sounds great the way it is, the HD600 is the headphone I choose.

My Setup

I use CD, Blu-ray, and DVD as my sound source. I mostly use a Marantz CD6005 but sometimes use an Onkyo C-7030 as my CD player. I use a bottom of the line Sony for video.

I drive all my headphones with a Schiit Asgard 2 headphone amplifier. Some of my other headphones sound fine being driven from the headphone output of CD player but the HD600 sounds significantly better with the Asgard 2 amp.

The HD600 is designed for home use. I do not use any portable listening devices and do all my listening exclusively at home.

I primarily listen to opera and orchestral music. I sometimes listen to jazz. If I watch a movie, the HD600 is my first choice of headphone. Movies are heavily equalized already and do not sound good with the added bass and treble boost of my other headphones.

The other headphones I currently own are the Sennheiser HD700, Beyerdynamic DT-880, Beyerdynamic DT-990, Beyerdynamic T51i, and Philips Fidelio X2.

My speakers are the Apogee Centaurs driven by an old Carver solid state amp and a passive preamp. I live in a small condo, so I cannot play my music very loud without disturbing the neighbors. I do most of my music listening with headphones and use the speakers for movies and television.

Sound Quality

The HD600 is known for its transparent sound quality. The sound is clear and detailed with sparkling highs and deep and detailed bass. Some will say that the highs are veiled and the bass is lacking but I cannot attribute that to the headphone as much as to individual recordings.

Out of the 6 headphones I currently own, only the HD600 and Beyerdynamic DT-880 are ones that I would consider neutral. All the others boost the bass and treble. It is important to have a neutral headphone because recordings are normally already equalized by the sound engineer and when you use a headphone that acts as an equalizer, it can mess up the sound. To further complicate matters, if the engineer is using a loudspeaker that does not have a flat frequency response to mix the recording, the sound balance can be drastically altered.

The Highs

The treble extension is a point of controversy among headphone aficionados. Many claim that the HD600 and other Sennheiser models have a veiled treble. I mostly use the HD600 for opera and most of my opera recordings do not sound veiled at all.

On the other hand, opera recordings that sound harsh on some of my other headphones can sound good on the HD600. So some people might want to call that veiled. I tend to think of the highs as “forgiving.”

I think the reason some people think the highs are veiled is that they are comparing the HD600 to some other popular headphones that have boosted high frequencies.

Regardless, the highs are fully extended and clear and most opera recordings.

The Midrange

The HD600 has a gorgeous, detailed midrange that I consider to be reference quality. The midrange is what made the HD600 famous.

The Bass

The bass is another point of controversy. Some think the HD600 does not have enough bass. I think they might be comparing the bass of the HD600 to headphones with boosted bass.

The HD600 does not have a boosted bass but the bass is well extended and has detail. It all depends on the recording. Recordings with good bass extension will sound warm and deep. Recordings without much bass will sound thin.

Since most of my other headphones add bass, I use my HD600 for recordings that already have a bass boost applied. For example, the remastered recordings of the Schumann symphonies conducted by George Szell have way too much bass added in the remastering. The original budget recording was just right. I cannot listen to the remastered recording on any other headphone than the HD600.

Soundstage

The soundstage on the recordings is accurately represented by the HD600 but like all headphones, the soundstage will collapse if you play them too loud. You have to get the volume just right for the soundstage to come into focus.

One of the best examples is the recording of Handel’s Alcina conducted by William Christie. If you get the volume just right, it is like sitting in the first row, right behind the orchestra pit; with the orchestra below you and the voices coming from the stage.

Conclusion

The Sennheiser HD600 has been around for 20 years now. I have had mine for 17 and I love it more now than ever due to my recent purchase of the Asgard 2 headphone amp. It is my reference when I compare other headphones for addition to my collection.

When reading headphone reviews, the writer usually treats the review as if the listener is only going to use one set of headphones for every recording. That might be true for someone listening to digital files going through an equalizer program. But I am listening to CD’s, DVD’s, and Blu-ray without any equalizer, so I end up using my headphones as an equalizer.

The Sennheiser HD600 is the one headphone I use when I don’t want to change the tonal quality of the music. It is my reference for a neutral headphone.

I usually turn to the HD600 for opera, chamber, and solo piano. For large orchestral music, I like the added bass and treble of my other headphones.

The HD600 is excellent for movies since they are already equalized with added bass and treble.

The HD600 is very comfortable and I can wear it for a long period of time, even while wearing glasses.

If you are a fan of opera and chamber music, I highly recommend trying out the Sennheiser HD600. Many other headphones have come and gone but the HD600 is my reference headphones that all others are compared to.

There are several versions of this headphone.  I am reviewing the Beyerdynamic DT 990 Pro, 250 ohm version.  This is one of 3 headphones I currently own.  I also have the Sennheiser HD700 and Sennheiser HD600.  My HD600 is 20 years old and might sound different from more recently manufactured units.  I listen exclusively to classical music and opera, so my opinions should be taken in that context. 
 
I have to say I originally purchased the DT 990 because it was selling at a discount from a marketplace reseller (not an authorized reseller) for a very low price.  Right out the box it sounded good and I enjoyed the sound for almost a year before I bought the HD700.  At the time I was just using the headphone output on my Onkyo C-7030 CD player and I stopped using the HD600 and the DT 990 and I was using the HD700 exclusively.  
 
I decided the upgrade my system by purchasing a Marantz 6005 CD player.  There was a slight improvement, but it was minimal.  Then I bought a Schiit Asgard 2 headphone amp so I could listen to opera on Blu-ray while watching it on television.  There was hardly any noticeable improvement in the sound quality on the HD700 but there was a huge improvement in the sound quality on the HD600 and DT 990.  Since I added the amp, I probably use the DT900 more than either of the Sennheiser headphones.
 
While some people seem to be pursuing a quest for the holy grail of headphones, I do not believe such a thing exists.  I use all 3 of my headphones and choose which one to use based on the quality of the recording.  
 
The HD700 is my choice for top quality recordings which have little or no flaws.  They have the extended bass and treble and amazing imaging that can only be reproduced from the best modern recordings.  On lower quality recordings or older recordings, they do not hide compression or rough treble or overzealous remastering.  These are my first choice when I watch opera on Blu-ray or listen to modern recordings of Handel opera.
 
The HD600 is good for recordings that have a harsh treble or a loose, warm bass.  The HD600 is known to sound good with a tube amp but even using a solid state amp like the Asgard 2, it makes recordings made on tube equipment sound lush.  My old recordings of George Szell with the Cleveland Orchestra sound especially good with these phones.
 
The DT 990 is good for older recordings that have the highs rolled off due to aggressive noise reduction (used to remove tape hiss) and for compressed recordings that lack punch.  This makes up the majority of my orchestral recordings.  Mahler's Resurrection Symphony conducted by Otto Klemperer and the Verdi Requiem conducted by Fritz Reiner are examples of recordings that sound magnificent on the DT 990's.
 
Overall Signature:  The DT 990's have a classic V signature with a significant dip in the lower midrange and upper bass.
 
The highs:  Some people say the DT 990's are too aggressive in the treble but for me it depends on the recording.  On the right recordings, the highs are clear, extended and detailed without any grain.
 
The midrange:  Some people say the DT 990's have a shallow midrange.  I used to hear a depressed midrange on some recordings when I was using the headphone jack on my CD player but ever since I switched to the Asgard 2, the midrange is clear and transparent.
 
The bass:  I have read mixed things about the bass on the DT 990's.  Some say there is too much and others say there is too little.  It really depends on what is on the recording.  The DT 990 has a fully extended bass so if there is lower bass frequencies, it will reproduce them.  This is something that many headphones will not do.
 
Dynamic Range:  Dynamic range is the difference between soft and loud and it is very important in Classical Music and opera.  Something like the Mahler First Symphony of Beethoven Ninth has parts that are whisper quiet and then get extremely loud.  Some headphones cannot reproduce the quiet parts accurately and others start to distort when they get loud.  The DT 990's have excellent dynamic range and sound great at both extremes.  Many headphones only sound good at loud volume.  The DT 990 can be played at moderate volume and it still sounds good.
 
Imaging:  Imaging and soundstage are very good but do not match the HD700.  On the HD700 you can locate every instrument and singer.
 
Comfort:  The DT 990's are the most comfortable of all the headphones I own.  They are lightweight and the earpads are soft and plush.  I have a bald head and and glasses and some headphones tend to slide around when I move.  I wish all my headphones were as comfortable as the DT 990's.  My only complaint is that the coiled cord is too short and it is not replaceable.  Beyerdynamic makes a "premium" version of the DT990 with a longer cable at a slightly higher price.
 
Build quality is excellent.  I am not the most gentle person in the world with my headphones and I use the DT990's almost everyday.  They seem very rugged.
 
The Beyerdynamic DT 990 Pro 250 ohm is the least expensive headphone I own by a significant margin but I use it more than my other 2 headphones.  When used with a high source input and a good headphone amp, they can make some flawed recordings sound amazing.  I don't believe a headphone exists that can make all recordings sound equally good but the DT 990 has a synergy with older recordings that really bring out the best.  
 
Anyone who listens to older Classical and opera recordings should add the DT 990 to their headphone collection.  We live in a world where Bose and Beats outsell all other headphone manufacturers combined and we should feel very fortunate that we have so many fine headphones to choose from.