[aznsensazian]

This looks very interesting. Anyone own these? They look ugly, but could be a great electret electrostatic headphone. Wualta, maybe this one might be in your expertise.

Here is a link .

 

[Jahn]

Argh don't mention Teledyne! I was at a meet today and forgot to bid for these - so cool looking, so cheap!

 

[aznsensazian]

lol, that looks ugly too. I mean look at that massive headband, and the coneshaped cups. What was teledyne thinking?

 

[Nights_85]

those look alot like pioneer se-l40's something tells me this was a general OEM design as ive seen another one of those headphones on ebay with a different brand on it.

 

[Oink1]

Quote:

Originally Posted by aznsensazian lol, that looks ugly too. I mean look at that massive headband, and the coneshaped cups. What was teledyne thinking?

Anyone for a pair of tea strainers?!

 

[ojnihs]

Quote:

Originally Posted by Oink1 Anyone for a pair of tea strainers?!

Haha that's great.

I've never heard of teledyne.. now I'm quite intrigued as to how they sound. Definitely not the best looking headphones I've ever seen... but like they say... can't judge a headphone by it's cover...

 

[Dusty Chalk]

I have noticed (in general, not absolutely) an inverse relationship between looks and sound...so based on that, these out to sound out of this world!

Someone buy these and tell us how they sound.

 

[kevin gilmore]

low bias privately labeled stax srx with different plastics.
circa 1978-1980

6 pin stax plug and the wire colors on the tails are a dead giveaway.

 

[wualta]

Quote:

Originally Posted by kevin gilmore low bias privately labeled stax srx with different plastics. circa 1978-1980.

But these are electret 'stats. That rules out the SR-X series, but could it be something like the SR-30? There were other small makers of electret 'phones back in the day, but the only ones I'm familiar with are Stax, Sony and Audio-Technica. Kevin, do you know anything about the Micro Seiki 'stats? Were those OEM'd by somebody we all know and love?

Until we can get a firm grip on their maker, I'd go for these 'phones only if they're cheap (OITC). They could be mediocre, as even Stax's electret 'phones were [that's a little harsh-- let's just say they were good but not great], or they could be surprisingly good, as Sony's were.

Teledyne's been around for a looong time. You found and still find their name on 'phones used in schools and libraries. At one time they owned AR, Acoustic Research. The tea-strainer 'phones do remind me of some nice but harmless old Pioneers from the '70s. No bass or treble, but what there was was smooth.

 

[edstrelow]

I owned several early Stax models inclduing the SR40? electret and a Sony electret. Both were pretty good, not quite up to the SRX MkIII. I think electrets may now have a bad reputation because electrets can loose their charge over time and become progressively less functional. I would be very wary of old electrets.

 

[wualta]

Quote:

Originally Posted by edstrelow ...electrets can loose their charge over time and become progressively less functional. I would be very wary of old electrets.

This gets repeated often enough to make me wonder where it came from. Can anyone quote a source documenting consistent and/or significant electret deterioration at room temperature and normal humidity over say 20 years? I'd love to read it. So would my 29 year old Sony ECR-500s.

 

[aznsensazian]

I have the akg k340 which are a dynamic/electret breed, and these have been produced in the late 70s. I havent had any problems with them thus far and to me they sound like new the day they were produced. What i mean by that is i dont notice the drivers failing on me and they sound livelier as lively can be. So maybe the electret headphones are stated to have a certain charge over time in the document, but there is no proof as far as i can tell of them dying 20-30 years later. The k340 was suppose to have a charge lasting 20-30 years but current k340 users have not reported of them dying.

 

[wualta]

I sure hope it was one of you guys who snagged those [admittedly untested] Realistic HP-100 (made by Stax?) electrostats on eBay this afternoon. $52 shipped-- not bad.

 

[edstrelow]

"Can anyone quote a source documenting consistent and/or significant electret deterioration at room temperature and normal humidity over say 20 years? I'd love to read it. So would my 29 year old Sony ECR-500s. " WUALTA

I don't know about official sources, but I recall reading reports from persons who have bought such units and have reported them to be poorly functioning. I am glad to hear that yours are still operating well.

 

[wualta]

My only goal is to reduce the general headphone anxiety level. Electrets are stable. Just ask Mead Killion, coauthor of a 1974 paper on the subject. You'll know him better as one of the founders of Etymotic Research. His paper can be found on the site of his former employer, Knowles Electronics. Anyway, the problem comes about most often, I suspect, when the user wants More Bass and overdrives 'em and trips a nonresettable thermal protector like a PTC thermistor. In an extreme case, if there are no protective devices, I suppose you could depolarize the electret in spots by arcing. That could happen, just as you can get a "grattle" from a certain wellknown brand of dynamic 'phones. But electrets don't just "lose charge" over time like a rechargeable AA cell does. At least, we can say: not over the average human lifetime.