It's been a very long time since I posted here, but I got something fairly interesting to share
.
Victor HP-D90
*I have compiled a few more pictures here:
https://imgur.com/a/JHcWMI1
I originally wrote a review/info post on them here:
https://www.reddit.com/r/headphones/comments/re9zb1/vintage_find_victor_hpd90_vintage_orthodynamic/
*I'm mostly copying and pasting it here to fit the Head-Fi format, so some wording may be more "beginner friendly" since I originally posted it on the headphones subreddit where people of varying knowledge and levels of experience frequent.
About the Victor HP-D90:
*If I get some info about the headphones wrong, please let me know with the correct info. There's virtually nothing written about these so I welcome all information that I missed or got incorrect. Most of the information I got/inferred is from
this page from
this database.
The HP-D90 was originally priced at 24,000 Yen in 1976 or about 43,600 Yen today. This was nearly 385 USD on headphones in the 1970s! People weren’t that ready to pay that much for a headphone back then which probably partially explains the rarity. Beats by Dre played a big role in normalizing paying big money for headphones today.
Victor is one of few Japanese headphone companies that manufactured and sold orthodynamic or planar magnetic headphones back in the day. Others were Fostex/Foster, Yamaha, and IIRC Sawafuji. Fostex most notably made OEM drivers that other companies used in their own models - the
Sansui SS-100,
Aiwa HP-500, and
Denon SH-90 (picture of an OEM of the Denon model) just to name a few. There were probably more who manufactured orthodynamic drivers that I’m forgetting but I just know there weren’t that many relative to companies who manufactured dynamic drivers. Just as background knowledge, Yamaha coined the term “orthodynamic” for their own planar magnetic headphones but it sorta was adopted among some enthusiasts when referring to planar magnetic headphones (especially older ones). I will be using both “orthodynamic” and “planar magnetic” interchangeably throughout this writing.
Victor, as far as I know, had one line of planar magnetic headphones: The HP-D30, HP-D50, HP-D70, and HP-D90. Both the HP-D70 and HP-D90 have the words Victor tried to coin “DYNA FLAT” printed onto the
badges onto where the yokes meet the headband. It didn’t quite catch on as strongly as “orthodynamic” did. The HP-D90 is their TOTL model whose drivers I don’t think were OEM’d to my knowledge. The drivers in the HP-D50 and HP-D70
were OEM’d to certain European companies though not Sennheiser or Beyerdynamic. Honestly, there’s still a lot I don’t know about the HP-D90 other than they’re extremely rare and use a unique driver that’s different from the relatively popular Fostex drivers. The magnets used in the driver as far as I can tell are
extremely thin magnets that are double-sided that run between the perforations of the metal grills. I am unable to open the assembly as it’s glued shut, but it really is crazy how thin the magnets seem looking at it from an angle.
Here is a picture where you see a diagram of the assembly of the HP-D90 driver. I think the voice coil is a
serpentine shape like the HP-D70 (or many modern planars) though with a more sophisticated design. Yamaha had
spiral shaped voice coils like on the
Final D8000 (Pro). The HP-D50 and HP-D70 use a single-sided magnet planar design which may be the first instances where we see such a design.
The death of the orthodynamic driver is said to be from the high production costs in its design. Dynamic drivers are much cheaper to produce and they can be made to sound very good. Of course now the technology has come back fairly recently and quite possibly stronger than ever.
Well, just in performance - just not in reliability amirite.
Specs:
- Design - Open-back
- Driver - Planar Magnetic/Orthodynamic, 66mm
- Impedance - 64 ohms
- Sensitivity - 95db (probably /mW)
- Max input - 300mW
- Frequency Response - 20-20,000 Hz
- Weight - without cable: 410 grams, with cable: 455 grams
- Production - From 1976 to 1981
Build Quality:
The headphones feel very solid and sturdy. The earcups and yokes seem to be made of some sort of metal. The inner baffle plate where the driver sits on is plastic.
The headband seems to be covered in vinyl. The cable is non-detachable and is fairly sturdy feeling. There is a bit of memory though it’s a very old headphone by now so I think it’s forgivable. The headphones terminate into a
¼” plug that looks and feels very high quality. In terms of weaponization, you can definitely really hurt someone with these if you whack someone with it. Both the chassis and drivers may survive. Speaking of which, the driver assembly does seem to be put together very well. With my time modding and taking apart headphones including a few planars, it definitely feels like a very durable and sophisticated design that’s not very prone to damage and everyday use unlike
cough Hifiman and Audeze
cough.
I usually like to take apart the assembly of vintage orthodynamics to snap a pic of the diaphragms and the driver assembly but it seems like the assembly is glued permanently shut so I’m not going to even try to open them. These are hard to find enough as is and I’m not gonna risk damaging something. There is a thin felt used as dampening on the rear of the driver and that’s it. This is to my surprise because other vintage planars typically have a fair bit of dampening material from the factory to tune the sound. Here, it’s just one single piece of thin felt on each side. I usually prefer a less damped system anyway as long as it sounds good.
One major thing to fault with the build quality really is how the front baffle is attached to the earcups: You snap it on. It has to be aligned very well or you will get air gaps and thus the sound will be off. Don’t even get me started on how to get them apart. When I received the unit, it showed signs of tampering on the left earcup such as not snapping on the front baffle back on very well, leaving an air gap. There were also marks of a flat head trying to pry the plastic baffle off. Why Victor had to overcomplicate things and just not use 4 screws is beyond me. The earcups definitely have ample space for a 4 screw assembly to work. It’s not major if you don’t plan on digging inside the headphones, but as a modder myself, it sucks.
Comfort/Fit:
With the stock flat earpads, comfort is uhh… not great. Hard vinyl earpads are never a good idea. It seems a lot of full-sized vintage planar magnetic headphones have these sorts of earpads - not sure if this is to preserve the (usually) flat response of planar magnetic drivers as much as possible or just having not put the R&D into the earpads. Maybe a bit of both but the result is that they’re not very comfortable to wear. I have to bend the metal yokes that hold the earpieces inward a bit so that I can get the earpads to seal over my head. Otherwise, there’s a huge gap behind my ear. On that note, there is very little horizontal earcup articulation making getting a good seal very difficult if the flat vinyl pads weren’t bad enough. Fitment is terrible without having to bend the metal yokes and/or changing the earpads. I’ve bent the yokes to my liking and put on Audio Technica ATH-R70X earpads, and they fit my head quite well. I don’t know how well this particular setting will fit another person’s head though.
They’re fairly heavy at 410 grams according to the database that I use. The headband seems to use a 2 splitted metal rod sort of assembly in the pleather headband. I think there’s a piece of cardboard in between the 2 rods completing the assembly. There’s practically no padding on the headband though the metal rods don’t dig into my skull surprisingly. It does a pretty good job distributing the weight of the headphones on my head.
Sound:
DAC: Schiit Modius
Amp: Topping A90
I primarily listened to these with the aforementioned ATH-R70X earpads so my impressions will mostly reflect that.
With the R70X earpads, they are fairly neutral sounding with a very slight lower mid and mid-bass bump. I chose these earpads because the flatter dimensions typically yield a flatter response without any reflections or peaks in the frequency response. I also like the foam density and fabric material that are used here.
Bass:
Bass extension is ok. With thick leather earpads, they can probably extend better but I typically prefer the more open sound and comfort of velour-type pads. Depending on the foam density and velour type, the flat sub-bass response may still be retained as with leather pads. Back to the headphones, there’s a slight lower-mid/mid-bass bloom - I think it’s about at the level between the HD600 and HD650. It’s very gradual and slight so I don’t find it boomy or thick sounding at all. There’s just a bit more “warmth” to the music than I’m used to with other planar magnetic headphones where the response is usually flat all the way down to the sub-bass. The texture of the bass is more like a dynamic driver’s response - more “rounded” sounding with a slower decay, and not tight and fast typically associated with planars. It’s not the most technically proficient but it’s still very pleasant sounding. Bumping the bass and sub-bass with EQ, and the bass really comes alive. In highly damped planar headphones, I can really only hear the sub-bass and mid-bass even with a bass boost. Here, the drivers don’t seem like they’re overdampened so I can really
feel the sub-bass rumble and bass thump when I put a bit of bass boost. Overall, the bass response is pretty good especially after bumping up the bass a bit and sound unlike most modern planar designs.
Midrange:
I think the midrange is where most of the magic lies (besides in another area that will be talked about below). It’s just great. Erm to elaborate, I mean that vocals just sound
right. Tonal balance is pretty spot on or at the very least, more or less to my liking/personal target when I EQ other headphones in the midrange. There’s a very slight and gradual rise to the mid-bass - when I say slight, I mean like a db or 2 at the
most from the lowest points in the midrange response. This gives vocals and instruments a slightly warmer tilt and as I mentioned in the bass section, it’s not thick or bloated sounding at all. The upper midrange is about level to where I like. The 1-5 kHz region is a bit laid-back from the Harman Target of which I find too shouty of a response for casual listening anyway. Because this region is also more laid-back the upper harmonics in vocals and instruments are less harsh and the perception of the soundstage/imaging is a little further/deeper from you rather than brash and in your face. Detail and resolution are fairly good.
Maybe at or around HD600 levels though the response here on the HP-D90 really just lulls me into the music to really care. Overall, the midrange response is great!
Treble:
Possibly the weakest point in the sound though it’s still a very good response for the most part. The region from about 5-10 kHz is pretty smooth sounding. I don’t notice any irritating peaks nor any holes in that region of the treble. The amount of treble around that region is about right as well. There is, however, HUGE amounts of air past 10 kHz. Enough to be very fatiguing for some music depending on the mixing and mastering. For well-mastered tracks, I think this actually elevates the experience or at the very least gives the perception of the headphones sounding bigger, wider, or more grand. Some parts are about 5 db more than most of the midrange which is a lot. This is also present with the stock earpads so I
think this is mostly a driver-related quirk/issue than an earpad related issue. Detail and resolution is better than I expected from a vintage planar. I expected a sort of “dull” or hazy sounding treble response but it’s actually quite good. Again, maybe at or around the levels of the HD600 or so.
Soundstage/Imaging:
I think this is where the other part of the magic lies. Ok so even with the stock earpads, and I would like to remind you that they are FLAT and hard vinyl earpads, the soundstage is pretty damn wide and open sounding. With the R70X earpads, take that and turn it up a notch. Ok well maybe that's a bit of an exaggeration but it’s similar to that of the R70X’s soundstage which I guess because the earpads are the same, how sound is coupled towards the eardrum is
sorta similar, different driver principles aside. For both headphones, I think the soundstage can be described as fairly realistic rather than diffuse like on the HD800 and some other planars.
The imaging performance shocked me the most considering this is a what? 40 year old headphone? Were the engineers even thinking of “imaging” in headphones that long ago? Was this just an accident? Because the imaging is great. I can very clearly tell where in the mix instruments are placed or where sounds are coming from in movies. I don’t really play shooters so I don’t know how it is for that but I’d assume they’d be pretty good. I think the soundstage and imaging with the ever-so-slight and tasteful warm tilt work together to create a nice and enveloping experience.
Obviously, this section is relative to other headphones and not speakers.
Measurements
Measured on a MiniDSP EARS. HPN compensation. Left channel at 90 db. The 3-5 kHz region on the MiniDSP EARS measured on most if not all headphones is inaccurate. The MiniDSP EARS is also not accurate at measuring the treble region though it does provide a bit of insight if overlaid with another headphone’s response. I typically identify dips and peaks in the treble by ear with a tone generator - how reliable one thinks that may be is how much faith they have in my ears. ..which might not be a lot understandably. ** Remember, only compare these measurements to headphones made on the same system (MiniDSP EARS) and the same compensation. In this case, there is the HEQ compensation (sorta Harman-eque IIRC), the HPN compensation (sorta diffuse field IIRC), and raw measurements (no compensation applied). Do NOT compare these measurements to headphones made on a different measuring system or you may misinterpret the comparison.
**I should also note that it was very hard to seal these on the MiniDSP EARS hence the difference in bass in both channels. As I mentioned near the beginning, the earcups have virtually no horizontal articulation so I have to bend the metal yokes to fit my head, and I’m way too lazy to adjust it perfectly for the MiniDSP EARS.
Conclusion/TL;DR:
To me, these are THE vintage orthodynamic kings. There’s
maybe one or two highly “mystical” vintage orthodynamics that I haven’t tried but shh let me have my moment. I’ve tried the original Fostex T50 (loved those), Aiwa HP-500 (was lukewarm about), Yamaha YH-1000 (hated), and Yamaha HP-1 (Anisotropic magnets, more or less the YH-1) to name the “mystical” and more sought after vintage orthodynamics. “Mystical” because they’re so hard to find at a decent price nowadays because of collectors like me coupled with being fairly rare. I think these Victor HP-D90 (with the ATH-R70X pad swap) tops them all. If it says anything, I have a Hifiman Susvara and I reach for these HP-D90 more than half the time nowadays. Not that it’s better, but it just sounds so different but good. To me, these are the auditory equivalent of a warm hug.
