A Review: Sennheiser HD-448 / HD-449

For a long time I have been listening with my trusty Koss PortaPro when I was on the go, itself a classic amongst headphones. The PortaPro has been on the market since 1984 and was THE headphone recommended for use with for example walkmans or discmans. Its bass heavy and dynamic sound is equally hated or admired though I for one always loved it as an example of a cheap headphone that sounds very well and is lightweight. The one criticism I always had was of course that it was an open headphone which means that it emits sound not only into your ears but also to the outside which could lead to ennerved neighbours (they too have to listen to your music). Since I don´t like that people might become aware that I´m listening to wonderful organ music I always desired to own another headphone, a closed headphone that doesn´t leak sound to the outside world. In the end I guess it took me roughly a year before I decided on a particular headphone. I toggled  through possible choices like the AKG K-450, the Sennheiser PX-200 II, the Sennheiser HD-448 or the Creative Aurvana Live! (which is the similar & much cheaper twin of the Denon AH-D 1001) but I finally made my decision when German HiFi magazine AUDIO published a test of the Sennheiser HD-448 with its most important sentence that "this headphone isn´t an example of extraordinary sonic experiences" - yet it received a good test result.

Sennheiser HD-448

That sentence was so important to me because of my own personal experience: when something that performs audio stuff isn´t described as being boring but as being unremarkable instead it most likely performs fairly balanced with a nod towards additional warmth. Gadgets reviewed as being very dynamic, with punchy bass, brilliant treble etc., traits that seem to describe lovely sound, actually have a built-in loudness curve which means that they´re far away from sounding balanced. While this loudness effect may result in a well-performed sound with some types of music it eventually will suck with all types of music: pop or jazz might sound lovely but classical music or rock will sound bad. I don´t want that because I´m not listening to one particular genre all the time. I experienced this myself with some of my vintage portable CD players, the Sony D-20 for example sounds just lovely with classical music (even better than the original) but not very good with pop music. While it´s easy to fall for a certain characteristical sonic direction I still want to enjoy Madonna one minute and Gustav Mahler the next and I don´t want to be disappointed by something that was engineered to fit one specific genre or the other, I want it to sound well with ALL genres of music. And nothing is more important than a balanced loudspeaker (a headphone consists of two tiny loudspeaksers really). So I put it onto my wishlist at amazon.de and waited for my birthday because that would be the date when my boyfriend would buy me this headphone as a present.

Sennheiser HD-448 earcup

While I was wondering that my boyfriend got it for so little money I was very happy with it the first minute I listened to it with my Sansa Clip+, I loved its sound from the start: fairly balanced (just as I expected) and a very impressive stage performance. The latter is important because closed headphones tend to have a more or less constricted stage impression, open headphones are regarded as having more "air" and a wider presentation. Well, the HD-448 partially defies these prejudices because its stage is wide and equally deep. True, the air is missing a bit but I have to be fair because I compared that particular aspect to my Sennheiser HD-600 - and that one is hard to match. How about the gain it can reach with portable devices? Well, it isn´t particularly loud with my Clip+, it doesn´t seem to be a very efficient headphone. You probably will have an improved performance with a small portable headphone amp like the FiiO E6. Does it distort much? Not from my experience, I´ve never managed to force it into distortions when using one of the EQ settings of the FiiO. It will of course distort when used with excessive volume, you might have read that on other reviews - I can only imagine how deafening loud those people are usually listening with headphones... their poor ears.

So the HD-448 grooves and it does so with an impressive deep bass, it´s tight, punchy when needed and while it doesn´t show the upper-bass-might of the HD-600 it never disturbs or bleeds into the lower mids. Ah yes, the lower mids... that´s where the HD-448 has its biggest problem because they tend to be too strong. On the one hand they are causing impressive warmth and a realistic chest for singers, on the other hand the sound can tip into slightly boomy territory. With an already very warm and balanced sounding recording this mellowness is too much, thankfully most recordings are engineered to sound a bit thinner - it also helps with some rather brittle sounding headphone outputs of portable players (it forms a perfect match with my Sony D-465) which is probably the reason why Sennheiser engineered it that way. The compared to the HD-600 diminished air is responsible for a bit less detail and resolution of course, in combination with the slightly boomy lower mids this creates a wide, fairly balanced and slightly warm sounding headphone. Don´t buy this headphone if you´re a fan of Beyerdynamic or AKG headphones because it sounds like their polar opposite. It´s never grainy or flashy and people preferring an aggressive, direct and treble-heavy sound probably will discern it as being boring. In my opinion however it is perfect for portable players and it certainly is more balanced than the Koss PortaPro.

Sennheiser HD-448

But I´d be lying if I´d describe it as being the perfect portable headphone - it is not. I´ve had roughly seven months not only to judge its sound quality but also its comfort level. That aspect has nothing to do with its build quality because that´s perfect. Have you noticed that it always looks cheap on pictures? Well, it still appears to look that way when it rests right in front of you - but the moment you touch it the impression of cheapness disappears. Its haptic is wonderful; the used plastic feels good and expensive. Secondly I feared that my ears would start to sweat wearing it for extended periods of time because of its pleather earpads. Thankfully this isn´t the case - which was the biggest surprise the HD-448 had in store for me: my head / ears won´t sweat, not even when it´s warm. But the question of "fit" is an entirely different thing and that´s where it partly fails - its earcups are too small. It doesn´t pose a problem for me (my earlobes are smaller than average and sit tightly to my head) but it will most likely be problematic for many other peoples: their ears may start to hurt after a short while because of their earlobes constantly touching the mesh covering the driver. The too tiny earcups also create another problem: since this is a closed headphone it needs to create an acoustic seal between your head and the driver in order for the headphone to perform at its best. The bass response will suffer if it doesn´t fit closely on your head / ears. So if your ears are too big - forget it. If your hair is too voluptous - forget it.

Sennheiser HD-448 earcup detail

I assume that this is one of the possible reasons why many people describe it as thin and aggressive sounding. Another equally valid reason for differing sonic impressions could be that Sennheiser changed the design of the HD-448 during its lifetime. Several frequency plots I´ve collected over the years can be interpreted as proof that its sound signature was changed into having more bass. As an example I´d like to present the measurment from headroom.com in comparison to the one by the aforementionend German magazine AUDIO:

Frequency response Sennheiser HD-448 (copyright by HeadRoom)

Frequency response Sennheiser HD-448 AUDIO magazine (copyright by AUDIO)

Sennheiser HD-449 frequency response

Ignoring that both might have measured differently it´s almost as if they measured two different headphones. You may note that the measurment from AUDIO magazine was done at the end of 2009 (it was used first by AUDIO's sister magazine STEREOPLAY (they described it as being too dynamic!)) while the headphone was released in 2007 and that´s probably when HeadRoom measured it. Judging from this it´s entirely possible that Sennheiser changed the sound midway during production. EDIT: Now I´m completely confident that Sennheiser changed their sound signature, just compare HeadRooms' measurments for the 448 to the one for the 449 I added above. I´m afraid that you cannot do anything about it should you have bought it when the HD 448 came out - but everyone else should just buy the successor, the Sennheiser HD-449. It´s the very same headphone, it appears to have the same frequency response as the one published by AUDIO magazine. Even Sennheiser admitted on their facebook page that the HD-448 and the HD-449 are exactly the same cans apart from cosmetic differences (cannot find their comment again). In any case I recommend that you try it on before you decide to buy it, it might not fit your head, it might start to hurt after half an hour of wearing it. You also may not like its sound but I assume that you won´t buy a Sennheiser anyway in case you´re interested in an aggressive and direct sound. But if you´re a bit like me you probably will love it, I´ve been very happy with it so far because it´s a very enjoyable headphone.

Pro:

• fairly balanced sound
• tight deep bass, full bodied sound
• wide and equally deep staging
• forgives bad recordings
• no distortions
• impressive timing
• sound never gets tiresome
• pleather earpads don´t get too warm
• perfect fit for small ears / short hair
• good built quality and haptic

Contra:

• can be too mellow, polite and muffled
• slightly exaggerated lower mids
• less upper bass
• could be more detailed and direct
• fit too small for average/big ears or too much hair
• cable too thin (typical for Sennheiser)

Last updated: 15.04.2014

More vintage portable Players compared!

EDIT: I´ll advise you to read the first paragraphs of another article about vintage portables. There you find the reasons for the strange sonic behaviour of the D-NE 1.

You know, I really have a lot of fun doing these little comparisons between vintage portable CD players. My first and my second articles were just a start it seems as I´m unable to stop buying these portables. I also enjoy listening to them one at a time, most of them do indeed have a better sound quality - even though they are quite bulky - than my lovely Sansa Clip+. Despite my initial dislike I´ve used the (now repaired) Sony D-465 quite often during recent weeks because it performs so well when I use it in combination with my FIIO E6 and my Sennheiser HD-448 (seems to be a classic synergy effect). The piercing treble and the slightly recessed mids form a balanced sonic partnership with the slightly recessed treble and exaggerated lower mids of the HD-448. I´ve also used the Sony D-20 a lot, it is a breathtakingly beautiful sounding machine. I´ve come to love its very stable and precisely described stage impression. In general it seems that I´m rather fond of players who tend to colour or tweak the sound a bit into a certain direction, a direction that isn´t faithful to the original sound of the recordings. It appears that I´m also fond of euphonic distortions and even though I consciously know that I´m listening to a lie my heart on the other hand simply won´t stop telling me that listening to these players feels so good. I´ve avoided the Technics SL-VP 50 during the last weeks for example, it sounds so damn close to the originals and my ASUS Xonar Essence ST that it doesn´t present anything new to me. Then I´ve listened to my old Technics SL-XP 300 a lot - and I can only say that I hate it! It seems to do everything wrong: while it shows a wide stage this stage tends to be flat with a lot of added ambience (distortions?), mids seem to be underrepresented. Well captured organ recordings are easily able to reveal the limits of this player in an excruciating fashion. Yes, this player lies too - but not very good. The Sony D-EJ 915 from my last review is something else too: while it fared really good I have been avoiding it. Not because it sucks, no, it´s only that it´s boring in its perfection (combined with that fuzzy stage that starts to disturb me) and therefore again nothing new. Let´s face it: while I strive to hear sonic perfection with vintage portable CD players most of the time I find myself actually preferring the opposite. I´ve always prided myself in being able not to fall for the typical audiophile preferences (an electronic device that "interprets" music in an engaging fashion) so I´m a bit ashamed of myself that I have a weak spot for euphonic sound. Naturally a machine is unable to intepret the music but many people seem to think that they do nonetheless. Both preferred players I mentionend are for instance unable to "interpret" pop or rock music - even more valid for the D-20 - but they are gorgeous with classical or orchestral filmmusic. Is this psychoacoustics? Probably.

One of my tools for casual listening: the FIIO E6

The other tool: Sennheiser HD-448

But today I´d like to talk about the Sony D-NE1 and the Technics SL-XP 490, my most recent additions. The Technics was released in 1995 and is one of the few players by Technics with an ESP. In Japan and the U.S. it was released with an optical output, the European version does not carry this handy advantage enabling digital recordings. When I take it apart I can see an empty space for it on the mainboard, the housing seems to be prepared for it too since it shows a cutout. I would have loved to record the digital output of the famous Technics portable CD drive with my MD-recorder Sony MZ-R 30 (btw, this will run out of competition for this review). Well, the Technics was quite cheap and in decent condition (the lid is scratched a bit) and it functions well, it has one of the fastest drives I´ve ever seen from a CD player. The Sony is a fairly modern and new player, it is in fact my most modern portable. Sony released it in 2002 to the market and it´s - apart from the lid - similar to the Sony D-NE9. I bought it in used condition from some idiot at Amazon.de (I could tell some stories you wouldn´t believe but I´ve decided to spare you this gruesome experience) for too much money, when new this player cost 250,- Euros. My player came with a cable remote control, an attachable compartment for two AA-batteries, a battery charging stand, software, a carrying pouch and headphones. The latter went to the garbage bin immediately but I was very happy to have the other additions since I can use the external battery compartment and the remote with the Sony D-EJ 915 too (only with that remote the EJ 915 is able to show CD-Text). The D-NE1 doesn´t have its own display because it has been attached to the remote instead - quite stupid if you ask me, I´d much prefer a display on the player itself but on the other hand it keeps the player small. The D-NE1 is also the only one of my players capable of playing mp3-CDs and just like the D-465 and the D-EJ 915 it boasts an optical output.

Technics SL-XP 490: not very beautiful if you ask me

Sony D-NE1: much better but abused

As you can see on the picture above the Sony was abused by its former owner. The lid appears to be severely scratched, even the battery charger stand shows some scratches. You know, this is something that I´ve never understood: why can´t people treat electronic devices with respect? Don´t these people prefer those things to work for at least 20 years or so? Don´t they prefer them to look good and proper for a very long time? Even if they are only portables? I wouldn´t want to be hurt, not even if I´d be a gadget like these. Despite the surface blemishes it worked very well from the start - a wonder really because when I took it apart to clean the flat ribbon cable and to lubricate the drive I noticed some liquid inside the compartment for the recheargable gumstick batteries, there even was some of it on the mainboard. Maybe some batteries lost their chemicals or the idiot who formerly owned the player poured something into it, I don´t know. Needless to say that I thoroughly cleaned it from the inside, including the mainboard which otherwise looked pristine. Anyway, now that I´ve cleaned it it looks and feels much better. I still have to wash the carrying pouch though; who knows how dirty the hands formerly touching it were? Remark: I just paused this article to do just that: handwash the pouch with warm water and washing detergent. The clear water turned into a brownish yellow! Yikes!

Details Sony D-NE1

The transparent, acrylic lid is made out of plastic but has a slap of round metal attached to its upper side. Despite its tiny size the player is suprisingly heavy and feels sturdy, the used plastic doesn´t feel cheap or fragile. I´ve also scratched my head before owning it myself whenever I saw some photo of the player because the photos seemed to show me a rather bulky player when in the accompanying text people constantly were talking about its small size. Well, I now appear to do the same because this player is really tiny. It´s even thinner then my Sony D-EJ 915 and only a bit thicker then a Jewel Case.

The outputs are a hint showing the actual size...

... but this comparison to a CD ("The Core") should make it clear immediately

Just for comparison I´ll also include a third portable: the Sony MZ-R 30. I don´t have a particular reason to do this, it´s just that I always was in love with the MD format the minute it was unleashed. The results of this recorder won´t turn up in my 'sonic pictures' but I´ll include the measurments since they highlight that a unit using lossy compression cannot be measured with the usual signals. The MD format was released by Sony in 1992 with the Sony MZ-1, a really horrible sounding and bulky portable recorder. It´s telling that the company used a portable recorder to present a new technology; the MD format is perfectly prepared for portable use. Housed inside a plastic case the little MO-disc is extremely durable, sturdy and able to withstand extreme stress (there have been cases where MDs have been crushed by a car - the MD case was destroyed but the disc itself was still working perfectly). Before the advent of Hi-MD lossy compression was necessary to reach the same runtime as the CD, the compression scheme used for that task is called ATRAC which is similar to mp3 but uses a much higher data rate.

Sony MZ-R 30

ATRAC (version 1.0) was used on the Sony MZ-1 and sounded like crap, clearly audible artifacts were introduced. Furthermore only a few companies offered pre-recorded MiniDiscs and so the new medium wasn´t very successful despite offering (a first back then!) delicious editing possibilities not unlike those possible on a PC. Only with the release of ATRAC 3.5 in 1995 it finally reached transparent audio quality mainly because of 32 Bit floating point internal processing, later MD recorders were even able to record and output true 24 Bit quality because of that. The ATRAC 4.0 chip used in my MZ-R 30 is nothing more than ATRAC 3.5 where three chips have been combined into only one. Since the MZ-R 30 was the first portable MD recorder to offer very good quality it was very successfull (even in worldwide markets) so you can still find a used one in decent shape on eBay. It was my first MD recorder and I´ve always cherished it, I´ve spent many happy hours with it. The built quality is perfect, the housing is made out of metal and it generally is a sturdy little thing. Why am I not including the results in my sound pictures? Because the sound quality is not only good (especially for a recorder using an early lossy compression codec) and balanced but a tad boring and uninteresting. There are some additional obstacles: sound quality differs depending on the material. Sometimes it´s full of details and sometimes it´s more mellow. The stage response however suffers the most with this unit for performers seem to change positions and size, it seems as if the stage is somehow fragmented. But it has a very impressive recording quality nonetheless for its age and size... which of course isn´t needed anymore nowadays since MD has become obsolete. HDD recorders offer better quality and even better editing possibilities while mp3 players took the portable playback market by storm with even smaller size and improved convenience.

Sony MZ-R 30 with opened lid

Measurments

As always, my "Measurments" are not really measurments in the strictest sense because I don´t own actual measuring equipment. So - as I did before - I used my E-MU 0202 USB for RMAA test signals and jitter tests (with the same cables and under the same conditions). Additionally the players were not powered by their batteries but by their AC power supply - just like with all my other tests. I recorded their outputs with 24/192 and downsampled the recorded results to 16/44.1 (non-dithered) later. Before downsampling however I amplified the amplitude of those signals to 0 dBFS only because RMAA doesn´t have an idea about absolute levels and also because portable players do not use the quasi-standard output voltage of 2 V on their line-outs. While this amplification distorts the noise responses somewhat (I could very well end up measuring my E-MU instead) it nevertheless represents a fair comparison because every result is level matched. The music examples were treated the same way - except that I amplified the calculated amplitude minus 1 dB difference. I do this to counter distorted peaks caused by inter sample clippings (many CD players react to them by putting out distorted or louder peaks) which in turn could pose problems for the resampling process. Needless to say that the digital originals I´d be comparing the results to have exactly the same amplitude, the same samplerate and bit depth (24/96). In case of the Sony MZ-R 30 my test CD and the music examples were recorded digitally onto MD with the D-EJ 915 doing the playback.

Sony D-NE1 - amplitude amplification to 0 dBFS: 8.6 dB

Technics SL-XP 490 - amplitude amplification to 0 dBFS: 10.5 dB

Sony MZ-R 30 - amplitude amplification to 0 dBFS: 8.5 dB

Sony D-NE1: perfect frequency response

Technics SL-XP 490: this deviation at higher frequencies should be audible

Sony MZ-R 30: lossy compression is the reason here

Jitter Sony D-NE1 - impressive

Jitter Technics SL-XP 490: equally impressive

Jitter Sony MZ-R 30: quantization noise (-> lossy compression) obscures the sine

All devices are measuring very well even though I don´t know how much the Sony MZ-R 30 jitters. But since jitter isn´t that much of a problem with more modern digital gadgets anyway I think that it can be ignored, I suspect that the Sony does its job well enough. What you cannot see however is how well the two Sonys reject imaging products, their stopband rejection works perfectly (keep in mind that the MZ-R 30 only uses a A/D-D/A converter combined into one chip!). The Technics however shows poor aliasing rejection: visible imaging products from 22.5 kHz onwards with clearly visible aliasing products reaching into the passband as low as roughly 14 kHz. It could be interesting for future measurments to look for impulse responses, the high frequency drop off of the Technics in combination with the imaging artifacts hint at a spline-like digital filter - or at a badly designed filter. The perfect 20 kHz-cutoff of the Sony D-NE1 is probably caused by a resampler; it´s perfectly possible that it´s using one since it has to be able to playback 48 kHz mp3- and ATRAC files so a converter that´s sampling at 48 kHz is most likely used (stupid me, I forgot to check 48 kHz playback with lossy files and I also forgot to look for the absence of two quartzes on the mainboard to confirm my assumptions). The sharp 18 kHz cutoff of the MD recorder shows that the lossy compressor ATRAC 4.0 cannot handle high frequencies when exposed to multi-tone test signals (and possibly music displaying a similar full frequency response), it simply erases them just like any other lossy codec would do (mp3 for example does this at roughly 16 kHz depending on the material and data rate).

Sony D-NE1 lid opened

Technics SL-XP 490 lid opened

Listening Tests

The Technics SL-XP 490 sounded wide and a bit distant. Sadly, the stage impression wasn´t very stable, performers seemed to move a bit from one second to the other. The stage also seemed to be lit a bit "dark", I don´t know any other words to describe it. Details audible in the digital originals weren´t always present but despite the measured drop-off in treble it didn´t sound too blanketed, it surprisingly sounded a bit too crisp. The sound is not really bad but not too impressive either, it doesn´t show the amount of recessed mids of the Technics SL-XP 300 and it also doesn´t show its punchy dynamics. Timing is well enough to not be bothersome. But: bass frequencies are too soft, they sound like a thick cushion. The decay (fade out of certain notes) disappears without much control. The Sony D-NE1 was the complete opposite with almost all characteristics: stage appeared a tiny bit too small and more holographic compared to the originals (which is a strange feeling if you´re not used to something like this). Apart from that it seemed to "jitter" a bit (performers seemed to wobble around slightly). Frequency response was balanced although I had the feeling that treble was too brilliant, resulting in a slightly nervous sound. But hooray!, this was the first player that got the bass right: it was strong enough, punchy when needed and very tight - not the soft mess the Technics presented. I´ve often read comments about the more recent portable Sony CD players that their bass supposedly is too overbearing - I doubt that this is true since the D-NE1 is the only one that closely matches the characteristic of the originals, it was a joy listening to "Swim" from Madonna's "Ray of Light". Still, there´s something strange going on: when I listened to the output with my FIIO E6 the stage was even smaller and more holographic, furthermore the too crisp high frequencies were gone. The latter were only apparent when the output was recorded with my E-MU 0202 and now I´m left wondering if the output of the Sony reacts differently to different inputs. As you may know, the input of a device presents a passive load (the resistance is measured in Ohm) to the (active) output so maybe the input of the E-MU presents a smaller (or bigger?) load (it must have an amplifier because the recording level can be increased - but does that change the resistance?), I really don´t know. Whatever the reason is, I prefer the more compact sound displayed with the FIIO E6 since it´s more balanced and also because the extremely controlled holographic staging is so appealing.

My perceived frequency response of the two players (via my E-MU 0202)

Perceived staging of the Sony D-NE 1 - exaggerated of course

Perceived staging of the Technics SL-XP 490 - exaggerated as well

Conclusions

Since I have mostly been listening to music with a player I formerly derided as being awful during my earlier tests (the Sony D-465) I´ll now be very careful to pronounce a winner. It could very well happen that I find myself listening to the Technics SL-XP 490 in a few weeks or that I´ll be listening to the Sony D-NE1 instead. The latter is of course the more portable player so it probably will receive more time to show what it´s worth. In any case, I have to expose myself constantly and unconsciously to all my players to find out how they sound. The comparably short reviews I´ve been doing were executed with the utmost biggest care of course but us humans tend to react differently when we listen to music while doing something else, like reading for example. This uncounscious listening was responsible for favoring the Sony D-465 and the D-20 over all the others, even though they colour the sound or are introducing some sonic errors. Therefore I reserve a final statement for some furture article where I will come back to all my portable CD players again - until then enjoy some more pictures.

Technics SL-XP 490

Sony D-NE1 from behind on its battery charging stand

Sony D-NE1 on its stand again - quite nice I think

Sony MZ-R 30 detail

Sony MZ-R 30 detail