[ericj]

It looks like I acquired my Pro 60 with 3rd party pads applied to it.

And it turns out, having received a few pair today from Koss, that the HV/X pads are something more similar to a grado 'bowl' pad. A thick foam pad witha crimp in the center.

This blurb from RadioShack- Audio/Video Electronics, MP3, LCD TVs, GPS, Digital Cameras, DVD Players, Accessories confirms the mixup:

Quote:

the great sound is possible because the contoured variable density earcushions are designed with an acoustic resistance to retain bass frequencies at the center, while allowing high and midrange frequencies to escape at the outer perimeters. This feature gives you the bass response of a closed type dynamic headset with the open and transparent sound throughout the midrange and highend.

Bah. Humbug.

 

[wualta]

Quote:

Originally Posted by ericj It turns out that the HV/X pads are something more similar to a grado 'bowl' pad. A thick foam pad with a crimp in the center.

You can be forgiven for thinking the flat pads were the originals-- every photo of the HV/X I've seen on the interwebs has flat pleather pads! ...which has puzzled me, because I remembered, or thought I did, that Koss had tried a variable-density (ie, HV-1 type) foam earpad with a triangular cross section.

But I'm thinking this variable-density foam earpad might come in very handy. So don't bah your humbug just yet.

 

[ericj]

Well, even stranger, the accessories list for the Pro 60 lists (iirc) two different part numbers for ear pads that have been replaced by a third part number. and it refers to a 'silver' version of the Pro 60 and a 'black' version. So who the heck knows - maybe mine were stock for my particular Pro 60.

the koss bowl pad was a major bass suckout for the pro 30, though. it's a shame - they're comfortable.

 

[wualta]

Interesting. Photos as you have time, please.

 

[wualta]

Coming: scans of the Sansui SS-100 sales brochure, courtesy of IceClass.


.

 

[d.phens]

If there can be headphones that can act as tweeters, example:TakeT, why not put them on your head?
Who has ever contemplated this at least?
Could it make sense? Does anyone know anything about giving proper bias to the tweeters or anything else about them?

Sometimes you can get a pair for some funny $30+shipping !

Here in the Orthodynamic Roundup somebody did contemplate mounting planar tweeters into headphones.

I hope I'm not disturbing...

 

[ericj]

Tweeter design usually doesn't worry much about bass backwave. They usually have a sealed back, in fact, which means they would have no bass at all in a headphone system.

And most ribbon tweeters are fairly heavy. I know the JVC and Infinity ribbon tweeters i have are far heavier than headphones ever should be.

That aside, the differences between Pioneer's HPM supertweeters and Pioneer's HPM headphones are vanishingly slight - mostly just the housing.

And sometimes ortho drivers are sold on eBay as tweeters - sometimes for as little as $20 for a quad. More frequently for $30 for a quad.

* SFI BIPOLE RIBBON TWEETER 4PC SETS EMIT-R TYPE 32ohm - eBay (item 280139614222 end time Mar-28-08 17:08:15 PDT)

Do you mean using AMT tweeters as headphone drivers? I'm up for that, if you know where i can get 'em cheap!

 

[d.phens]

Not only that, I'm afraid I'm 'pwning' the thread and going off topic.
I thought of some electrostatic tweeters, some of which are open.
How are they in a normal, non-powered speaker like the old Jensen powered?
I did see some for sale for astonishingly (what an astonishing word) low prices, such as $5 but nobody bought it anyway

I saw a post here after using the notable search function.
Should I post in the Stax thread? The fun is that what I want is completely inbetween, neither DIY nor speaker nor headphone forums deal with that.

 

[d.phens]

Another question is - did anybody try just to re-plug (or de-plug) the ortho headphones and attach them to speaker terminals of a power amp?
Is it safe to do with TRS-terminated electrets (which have those small x-formers inside caps or on a pod)?


I mean the new T-amp would be nice, or perhaps something vintage (what?) That would change the whole thing as orthos get too little buyer attention because they're hard to power.

 

[ericj]

Quote:

Originally Posted by d.phens /img/forum/go_quote.gif Not only that, I'm afraid I'm 'pwning' the thread and going off topic. I thought of some electrostatic tweeters, some of which are open. How are they in a normal, non-powered speaker like the old Jensen powered? I did see some for sale for astonishingly (what an astonishing word) low prices, such as $5 but nobody bought it anyway I saw a post here after using the notable search function. Should I post in the Stax thread? The fun is that what I want is completely inbetween, neither DIY nor speaker nor headphone forums deal with that.

Ah, i should have realized when you mentioned biasing.

iirc it's been done - the Mk1 Float used tweeter panels, iirc. The Stax Thread is a better place to ask - we mostly talk about planars that are not electrostatic here. We try to stick to planar magnetics but sometimes piezos and low-end stats come up.

Quote:

Originally Posted by d.phens /img/forum/go_quote.gif Another question is - did anybody try just to re-plug (or de-plug) the ortho headphones and attach them to speaker terminals of a power amp? Is it safe to do with TRS-terminated electrets (which have those small x-formers inside caps or on a pod)? I mean the new T-amp would be nice, or perhaps something vintage (what?) That would change the whole thing as orthos get too little buyer attention because they're hard to power.

It's usually not necessary with orthos. You don't need more than a few watts of power for even the meanest orthos, so any above-average headphone jack should work fine. Some work better than others, but the meaner pocket amps - even the ones that run off a single 9v pack - can do orthos justice.

As for 'trets the real hotrod option is to put a stax compatible plug on them and use them with a regular 'stat amp or transformer box - but yeah, assuming you keep the grounds separated, there's no reason not to hook the stock eensy transformers up to a speaker amp.

 

[wualta]

I like this cross section drawing...

Here's the frequency response graph with impedance and harmonic distortion thrown in. Too good to be true? Probably. But it does underline the impedance=resistance advantage of isodynamic drivers.

Nice photo of the headphones-- nicest looking of the Fostex OEMs we've seen so far.

If anyone's having trouble reading the brochure's text in IceClass' earlier post, let me know and I can zoom in on it. Thanks again to IceClass for forking over the big bucks to an eBay brochurist for this trip into the isodynamic past.

 

[ericj]

Looks like T20 pads would be a good idea for my adaptation of SS100 drivers.

 

[wualta]

Thanks to ericj for fielding that question about planar tweeters as headphones.

It's not a sure thing. Many are designed not to attempt the reproduction of bass frequencies. Their diaphragms will be stretched tight, which will preclude bass reproduction even in a headphone configuration, or the back will be closed, which again kills bass but "amplifies" treble-- or both. However, you never know what the designers had in mind until you try it.

The original Jecklin Float used Janszen electrostatic tweeter panels, and sure enough, it had no bass. Something intended for computer speaker use might show more promise. I mentioned the panels from a Monsoon planar-magnetic satellite panel earlier in this thread, but I didn't seriously intend to recommend them as possible headphone drivers. Not without a subwoofer, at least.

 

[wualta]

Quote:

Originally Posted by ericj /img/forum/go_quote.gif Looks like T20 pads would be a good idea for my adaptation of SS100 drivers.

T20v1 or 2? Anyway, Woodang has one genuine SS-100 earpad left.

 

[PDOT]

Sansui SS-100 looks great! Frequency responce is very good too. It seems to me it is one of the best orthodynamic headphones.