Pioneer SE-L40

Just got these headphones in new old stock condition, completely unused. The headphones were still in the plastic bag and the cable still had the original plastic tie. the original  hard case was included; the quality is decent and does a good job of protecting the headphones.
 
First Impressions:
 
When I first opened the box and removed the plastic, I was completely stunned at how well everything was made and shined the perfection. Picking it up, they're surprisingly light for an almost all metal and leather construction. The cable is of very good quality. It's braided and terminates into a rather long/sturdy 1/4 inch jack.
 
Build Quality and Looks:
 
The headphones are almost exclusively metal. Every major part of the headphones is made out of metal. (cups, headband, etc.) The construction feels very solid (as expected) and would probably be very hard to break. Clamping force is a tad bit tight but the pads are very comfortable. The leather covering on the headband is very nice and goes well with everything else. In terms of how nice the headphones look, I'd give it a solid 10/10. I've never seen a pair of headphones that are this beautiful. They've got that retro, vintage vibe and just oozes elegance. It's a bit like a vintage Mercedes.
 
Sound:
 
Source: iPhone 4s (The lowest impedance source I have at about 1.8 ohms to accommodate the low impedance of the Pioneers at 8 ohms)
Music: Uncompressed, 44.1 khz, tested with Pink Floyd's Dark Side Of The Moon, Led Zeppelin IV and John Coltrane's A Supreme Love
 
Bass: Very deep, pronounced bass. It's slightly more than I'd like although I admit, I tend to prefer headphones that are very light on bass. In comparison to AKG K7xx's and Sennheiser Momentums, the Pioneers definitely have more bass.
Mids: This is definitely where these cans shine the most. Very rich, velvety, lifelike mids. The saxophone parts in Us And Them sound incredible.
Treble: The high end is a bit subdued. This is probably caused by the pads as they are practically pillows. There is a thick layer of foam between the driver and your ear and there isn't a hole in middle of the pads as you'd normally find on most headphones. You could probably mod the pads (cut out a section) to let the sound come through easier.
 
Overall, The headphones work well with rock but doesn't handle well with music such as dubstep, edm, etc. With jazz, it's a whole new world. The headphones seem to perfectly accentuate the upright bass, sax and drums of John Coltrane's A Supreme Love. These headphones seem to be made for listening to jazz. As a bonus, the soundstage and instrument separation is surprisingly good. I could easily pinpoint every hit of the timbales and congas in Santana's No One To Depend On.

Lets jump right into it!
Design:
The Pioneer SE L40 are basically the vintage counterpart to the legendary Sennheiser HD25. Similar design but instead of plastic these are every steampunker's dream. They are made from beautiful brushed steel in silver and gold-ish finnish, a headband of durable red/brown leather and a cable with a braided mesh that is almost identical to the one on my Denon 2000, which then terminates in a rugged but quite big 1/4" jack connector. 
The only drawback to the design is the pillow like pads, that has been subject to many accusations of muffling the sound (I have yet to find out wether this is true).
All in all these are built as (and of the same materials as) an old tank. But this didn't stop them from being the most comfortable on-ear headphones i have tried so far.
 
Accessories:
The headphones comes with a carrying/storage case/box, a manual and a cleaning cloth. Last two are not of much use, but cool to have. The box though is probably the only reason these headphones are in such pristine state - its lined with a silk-ish material and has a cushion of foam shaped to fit the headphones where they can rest, and a strap in the lid that will hold the manual. Great accessory to protect this sleeping beauty (Slept for 40 years or so).
 
Sound:
Now for what you have probably been waiting for...Sound! I have read from several people that these need amplification, even though their specs wouldn't make me think so. I've been using these with my Aiptek ImAmp with the following sources: Iphone 4, Macbook, Old Technics record player. The coupling with a record player from the same year as the headphone and an original Judas Priest: Hero, Hero record from 74' is in a category of its own! Its like a step back in time an something any audiophile should get the chance to try - I will however no be reviewing it from this source since it's as mentioned in a "class of its own". 
Now to more conventional sources! I mentioned that the headphone may seem slightly muffled, but don't let this statement scare you! Its is barely noticeable after a minute of listening. I will review each quality i find important in this headphones sound:
Highs and Mids: The overall sound of this headphone is slightly darker than my usual headphones but it does a tremendously good job at these. The higs are slightly airy but balanced, not rusty or squeaky as it can be with some old phones. The mids are so well pronounced that i can hardly put my finger on anything to say, its just as it should be. These qualities makes this a great headphone for acoustic music such as Dominic Frasca's album Deviations as well as the acoustic cd by Godsmack called The Other Side.
 
Bass:
This is not for bassheads. The bass is well balacnced to the rest of the headhones specs, but less punchy than on modern headphones, something that has only bothered me slightly when listening to house music such as Deadmau5, but can also be very pleasant in this genre. This quite unique type of bass-response makes this headphone very pleasant to listen to for a long time.
 
Speed? You got it:
Even though this is old, its still ably to keep up pace with melodic death metal such as Children of Bodom as well as the quick didgeridoo rythms Si's album Let The Spirit Out. 
What I'm saying is that you shouldn't worry about this factor.
 
Instrument separation/presentation and soundstage:
This part is mind blowing. I could spend days and nights wrinkling my brain, trying to figure out how they did it but this headphone will beat many modern headphones to the pulp on this. The ability to hear each separate instrument and where it is positioned with this headphone is simply ming boggling and even with modern headphones i have rarely experienced competitors.
 
What genres will this fit?
Many! Though listeners used to an ocean of earthshaking bass wont find this headphone to their taste. This is a very balanced headphone and I find that is especially good with acoustic guitars and...Didgeridoos anyone? It is very good at different types of rock and metal. Electronica and ambient will also give a very pleasant listening experience - this also goes for house music, but as mentioned the bass wont kick your head in.
In general terms the only genres this won't do are ones with a bass that needs to be able to break walls. 
"Old" music like The Doors, Judas Priest and Sinatra will give a experience to remember as a historical vu, and a milestone for headphones in my opinion.
 
Useful specs:
1-1/2" dynamic speaker
Open back design (low sound leakage)
Impedance: 8ohm
Frequency response: 20 - 20.000Hz
Max input: 30mW pr. channel
Cord: 3m / 9,8 feet
Weight: 230g (you wont feel a thing)
 
Conclusion:
This is a historical milestone! Fantastic looks, build quality at its best and sound quality that wasn't to be heard again for many years to come. If you have the chance to grab a pair of these, do it! The price may vary from nothing to everything depending on the state of the headphone.
These cans will do what ever you want, though it would be a good idea to feed them through a decent amp to get the best result. 
 
Note: Paired with the Fiio E11's bass boost function these really shine! It makes up for the the only part of the frequency these lack on (because of the time they were made).
 
 
 
 

These are gorgeous headphones that show off both Pioneer's stellar engineering and prowess in vintage music reproduction.
 
I found my pair to be very mid forward while light on the low end, a bit recessed on the high end and clarity is lacking; all though this creates a warm and forgiving coloration. A few of us considered the pads to thank for the lack of clarity as they are basically tiny pillows that are filtering the music. If you're a fan of some great, but sadly, poor quality music (classical, blues, jazz, etc.), I find that these really do help you gain that feel of playing them off an old record player-- they're very forgiving so even with the cracks and pops from the song's recording, they still manage to make the song lovable.
 
To be brief: they're great and exciting if you're looking for something new, a restoration project, a modding project (please inform us / contact me if you plan on mods!) or even work well as a displayed object in your house or office to express your love for the hobby as they really are beautiful looking classic headphones. They are not a headphone to be missed by the vintage lover!
 
Those looking to buy: eBay often has a few auctions a week for the SE-L40s, so keep your eyes open and look for a good price and a good condition pair.
 
- Evan