[scootsit]

I recently picked up some really old headphones online.
These have got to be some of the coolest headphones I've seen in a while, mostly because they are so old!
 
They are labelled Safar R2000.
 
Here's a picture:

 
They look a lot like the AKG K10. They use one of the weirdest drivers I have ever seen.
 
The earpieces have a copper ring around the outside of what appears to be bakelite.
A piece of metal is sandwiched between that and the driver.
The driver is a pair of electromagnets, with a magnet behind them.
The electromagnets move the piece of metal.
 
Comfort? None.
Sound? It's hard to tell, these odd drivers are reading at 4.35K ohms.
I assume they were designed to be run by a speaker amplifier, but I really have nothing that can drive them set up for cans.
Given that they are wired for mono, and the drivers are in parallel, that means that each driver must be around 8.7K ohms, which is pretty insane.
 
I cranked the volume on my amp and got a bit of sound out of one of the cups. I'll tinker some more, and maybe hook them up to my speaker amp and edit this post as I do.
Here are pictures of the drivers:

 
And one more picture:

 
Anybody have any information about Safar? Anybody have these? Really, anything?

 

[scootsit]

I have since found out that these are moving iron drivers. I am going to try to recable them, I think. I'll post my thoughts once I do.

 

[obobskivich]

Instead of going massively OT in the Grado thread, I'll post here!

Have you re-wired these yet?

Also, you might able to get some pads for them - I'm imagining the DT48 pads to fit, but there are probably others as well. It will likely change the sound.

As far as what drives these - that'd be a crystal radio. More: http://en.wikipedia.org/wiki/Crystal_radio

To run them on a modern amplifier (of more or less any sort) you'd want a transformer.

Thanks for sharing the pics in the other thread!

EDIT

Did a bit of looking on my own on these, couldn't find much on the headset itself, but found that "SAFAR" is likely an acronym for "Società Anonima Fabbricazione Apparecchi Radiofonici" - an Italian company. Founded in 1923, and apparently one of the first companies in Italy to be involved in television starting the early 1930s (and that's what most of the history is focused on). They ostensibly went under during or after WW2.

These are likely from the late 1920s or early 1930s (best guess) - dynamic driver headphones and vacuum tube based radios came about in the mid to late 1930s and were adopted fairly quickly by military users and became fairly common into the 1940s, and the company seems to have been more interested in military technology and television moving into the later half of the 1930s.

That's all I found.

 

[scootsit]

Quote:

Instead of going massively OT in the Grado thread, I'll post here!

Have you re-wired these yet?

Also, you might able to get some pads for them - I'm imagining the DT48 pads to fit, but there are probably others as well. It will likely change the sound.

As far as what drives these - that'd be a crystal radio. More: http://en.wikipedia.org/wiki/Crystal_radio

To run them on a modern amplifier (of more or less any sort) you'd want a transformer.

Thanks for sharing the pics in the other thread!

I emailed (I paraphrased our emails below) this guy who has a passion for these old sorts of cans. He told me that yes, they are in fact designed for crystal radios or speaker amps. He told me not to recable them and that the impedance I was reading was exactly right, they were that big so that they could be used with speaker amps, so no I haven't. I'm setting up a small nearfield system with a really low power realistic amp and some Minimus speakers. I'm thinking I'll build a little adapter and hook them up to that. I have used it with my Millet Mosfet, and listened to them, they sound exactly like you'd expect, like an old radio, which is neat. They have zero extension on either end, but they're fun. The pictures I've seen of similar ones have no pads, so I was thinking that they didn't need pads, they're really uncomfortable though, so maybe I'll get some.
Here's his site: http://oldheadphones.com/
 
He emailed me this:
[size=10pt]They look like late 1920's or early 1930's European make headphones. They were probably 2000 ohms each side for total of about 4000 ohms, so your measurements are in the ballpark. If you have an ohmmeter you can measure the DC resistance of each of the 2 earpiece units to verify they are the same, and if so, just need to put the diaphragms on so they don't touch the magnets.[/size] [size=10pt]They were wired in series. Not very good frequency response, the metal diaphragms don't move well, like the modern cones.[/size] [size=10pt]They look similar to some that were from Germany and Austria. [/size]
 
[size=10pt]I found out that Safar was a German speaker manufacturer.[/size]

 

[obobskivich]

I've never heard of running a crystal headset on speaker taps - they're designed for almost currentless drive (not unlike ESPs, although I'm skeptical they'd like you very much if you ran a few thousand volts across them!). A big speaker amp will run very inefficiently into that load, and may have problems with it (depending on the amp, and how they react to it). A transformer would be the safe bet here imho. Might wanna give this a glance before you hook'em up to modern amplifier: http://en.wikipedia.org/wiki/Moving_iron_speaker

Regarding pads - realize that anything made from rubber, vinyl, leather, etc from the 1920s or 1930s has long since disintegrated. I don't actually know if they came with pads, but I'm inclined to believe they would have (or at least fabric covers). That doesn't mean you can't add some to make them wearable, but I would expect at least some change to the sound (no idea if it would improve or detract).

I've seen that site before, but assumed it was dead by now.

What was his reason for not recabling them?

 

[scootsit]

Quote:

I've never heard of running a crystal headset on speaker taps - they're designed for almost currentless drive (not unlike ESPs, although I'm skeptical they'd like you very much if you ran a few thousand volts across them!). A big speaker amp will run very inefficiently into that load, and may have problems with it (depending on the amp, and how they react to it). A transformer would be the safe bet here imho. Might wanna give this a glance before you hook'em up to modern amplifier: http://en.wikipedia.org/wiki/Moving_iron_speaker

Regarding pads - realize that anything made from rubber, vinyl, leather, etc from the 1920s or 1930s has long since disintegrated.

I don't actually know if they came with pads, but I'm inclined to believe they would have (or at least fabric covers). That doesn't mean you can't add some to make them wearable, but I would expect at least some change to the sound (no idea if it would improve or detract).

I've seen that site before, but assumed it was dead by now.

What was his reason for not recabling them?

Well, they've more or less been shelved because the semester started. But, my main reason for recabling them was because I thought the oxidized cable was causing the ridiculously high impedance, once I found out that was normal, I decided it wasn't a priority. Also, they have this really cool cotton cable cover, that I knew I'd never be able to get my recabling into. I honestly threw that out that amp as an idea, I have put very little thought into them, I graduate in December, so I'll start thinking about it a bit more then, most likely. I'll do something with them. Hell, maybe this is an excuse to build a crystal radio! I have some of those radio shack impedance matching transformers, I normally use them with my IEMs to boost the current and drop the voltage, maybe I'll plug them in backward and see how they sound. That's actually a small enough time commitment, I can do that now!

 

[obobskivich]

My fear would be that the cable under that cotton is probably like paper-wrapped aluminum or some other garbage. I *loathe* old electrical wiring (because it's just a fire waiting to happen). In the Grado thread, someone (I think parbaked) mentioned using shoelaces for DIY cotton sleeving on cables, and I know that techflex comes in more colors than Crayola knows about, so there are certainly options to re-do this with modern (and safe) wire.

But yeah, the reason these are a bajillion ohms is because a crystal radio can't supply hardly any current - your big speaker amp will want to supply an ocean of current (comparatively). Oh, and FR will change with amp HEAVILY because these are highly inductive (should've seen that coming, based on the design). So there is no "normal" unless you play with EQ and so on - Wiki suggests dropping LF to prevent a low Z overcurrent scenario (this is also partly why I vote transformer).

 

[scootsit]

Quote:

My fear would be that the cable under that cotton is probably like paper-wrapped aluminum or some other garbage. I *loathe* old electrical wiring (because it's just a fire waiting to happen). In the Grado thread, someone (I think parbaked) mentioned using shoelaces for DIY cotton sleeving on cables, and I know that techflex comes in more colors than Crayola knows about, so there are certainly options to re-do this with modern (and safe) wire.

But yeah, the reason these are a bajillion ohms is because a crystal radio can't supply hardly any current - your big speaker amp will want to supply an ocean of current (comparatively). Oh, and FR will change with amp HEAVILY because these are highly inductive (should've seen that coming, based on the design). So there is no "normal" unless you play with EQ and so on - Wiki suggests dropping LF to prevent a low Z overcurrent scenario (this is also partly why I vote transformer).

It looks like cotton wrapped copper, but your points are well taken, for any real serious work, I'll recable them. I'll probably just drive myself nuts getting my new cable into the same sleeve.

 

[scootsit]

I just threw it on my ipod with that adapter backwards.
Zero bass, as expected. There's some weird resonances, but there's part of the mids and part of the top that's actually pretty decent, with some EQing, I could probably get something fun here. The top end extension actually isn't terrible.
I stuffed KSC75 pads between them and my ear, and it got rid of some of the ringiness, it's actually not that terrible, I mean, it's not good, but I could listen this, there's actually some decent detail.
Don't get me wrong, they're not competing with even the cheapest can you've ever heard, but still, given what it is and how it works, it ain't as bad as you'd expect.
 
I have a mediocre recording of Cab Calloway, that acutally sounds about the same on these as it does on my Grados, because it's seriously cut off at the top and bottom. I'm digging this, I think I will definitely be listening to more Cab on these suckers.

 

[scootsit]

I threw them on to test, got distracted, and am still listening, really enjoying them. I just found out that the Grado Flat pads fit, adding some more depth to the song. I'm going to order some HD414 pads some day, and throw them on here, I've been looking forward to trying those on my Grados, so now I have an excuse to order some. These really are fun sounding with big band music. The FR seems to really capture brass.

 

[Desi]

Funny cause recently i found these cans too!
They were my fathers and they were in such abad condition
I had to work 1-2 days to rebuild them and here they are!



Just 2 questions:
Can someone let me know where the "+" symbol is on the magnets(left or right)??
Are the magnets touching the diaphragm (metal plate) or not??

I'm really wonder about the sound!

 

[Sinery]

Funny cause recently i found these cans too!
They were my fathers and they were in such abad condition
I had to work 1-2 days to rebuild them and here they are!



Just 2 questions:
Can someone let me know where the "+" symbol is on the magnets(left or right)??
Are the magnets touching the diaphragm (metal plate) or not??

I'm really wonder about the sound!

>Recently too
>Last post was from 2012

 

[Desi]

>Recently too
>Last post was from 2012

Ok so what? Do you know any other "recent" topic with this subject??

 

[scootsit]

As I recall, one side of the magnet is painted red, and I think the magnets touch the metal plate, it's adjustable by turning the ear piece.

That's all based on my recollection. I'm by no means an expert, and I haven't played with these much in years.

They sound all right, very different than anything contemporary, but they need higher voltage (albeit at low current), you may even need a step up transformer.

I emailed Scott at http://oldheadphones.com he gave me a lot of info. Anything I say should be taken with a grain of salt, and instead, consult him..

Good luck!

 

[Desi]

As I recall, one side of the magnet is painted red, and I think the magnets touch the metal plate, it's adjustable by turning the ear piece.

That's all based on my recollection. I'm by no means an expert, and I haven't played with these much in years.

They sound all right, very different than anything contemporary, but they need higher voltage (albeit at low current), you may even need a step up transformer.

I emailed Scott at http://oldheadphones.com he gave me a lot of info. Anything I say should be taken with a grain of salt, and instead, consult him..

Good luck!

Thanks for your help !
On mine the magnet plates are all black with a + symbol on one side and to be honest is did not meantion if it was on left or right side

btw someone in Italy sells the same and give some info about :
"Used by Air Force pilot. Double headset made of metal. The company's anonymous factory radio equipment in operation from 1923 to 1948 was one of the major Italian companies in radio for military purposes. It forced to close without being able to demand the large credit contract with the Armed Forces during the war."