Orthodynamic Roundup

[wualta]

Indeed. One of the fundamental tenets of this thread is that vintage ortho 'phones can often (not always, but often) provide almost any kind of sound, including bass sound-- call it your personal bassstyle-- from frighteningly tight to mellow and all the way to downright floomfy, depending on the owner's willingness to spend time and effort and which headphone he/she starts with. I personally tend to push perceived-flat response and tight bass (because I'm a waveform-fidelity kinda guy), but that's not the only option. 
 
SFI: Don't forget, this is one of those off-label "it's not supposed to work" things. The SFI was originally meant to be a tweeter, one of an array, in a gigantic panel-shaped multiway dipole speaker built by Sawafuji back in the '70s. And nearly all the SFI drivers you'll find for sale today really are tweeters and nothing more-- ours is the dipole version, which gives it a special dispensation. Regardless of its hidden talents, since it was meant as a tweeter, it's spec'd that way. But just as Sennheiser's reputed to have used a microphone capsule to create the HD 414 headphone, sometimes off-label works just fine.

 

[vid]

 

 

 
Doing the blu-tacking this way doesn't seem to introduce the ringing around 5 kHz that happened when I put the tack on the front end rim of the driver.

 

[scompton]

Quote:

Indeed. One of the fundamental tenets of this thread is that vintage ortho 'phones can often (not always, but often) provide almost any kind of sound, including bass sound-- call it your personal bassstyle-- from frighteningly tight to mellow and all the way to downright floomfy, depending on the owner's willingness to spend time and effort and which headphone he/she starts with. I personally tend to push perceived-flat response and tight bass (because I'm a waveform-fidelity kinda guy), but that's not the only option. 
 
SFI: Don't forget, this is one of those off-label "it's not supposed to work" things. The SFI was originally meant to be a tweeter, one of an array, in a gigantic panel-shaped multiway dipole speaker built by Sawafuji back in the '70s. And nearly all the SFI drivers you'll find for sale today really are tweeters and nothing more-- ours is the dipole version, which gives it a special dispensation. Regardless of its hidden talents, since it was meant as a tweeter, it's spec'd that way. But just as Sennheiser's reputed to have used a microphone capsule to create the HD 414 headphone, sometimes off-label works just fine.

 
I remember reading somewhere that speaker frequency response is measured 1 meter from the speaker as well.  Just a guess but I'd bet that the drivers in just about any  headphone would measure as a tweeter at 1 meter.  

 

[Hutnicks]

Quote:

Indeed. One of the fundamental tenets of this thread is that vintage ortho 'phones can often (not always, but often) provide almost any kind of sound, including bass sound-- call it your personal bassstyle-- from frighteningly tight to mellow and all the way to downright floomfy, depending on the owner's willingness to spend time and effort and which headphone he/she starts with. I personally tend to push perceived-flat response and tight bass (because I'm a waveform-fidelity kinda guy), but that's not the only option. 
 
SFI: Don't forget, this is one of those off-label "it's not supposed to work" things. The SFI was originally meant to be a tweeter, one of an array, in a gigantic panel-shaped multiway dipole speaker built by Sawafuji back in the '70s. And nearly all the SFI drivers you'll find for sale today really are tweeters and nothing more-- ours is the dipole version, which gives it a special dispensation. Regardless of its hidden talents, since it was meant as a tweeter, it's spec'd that way. But just as Sennheiser's reputed to have used a microphone capsule to create the HD 414 headphone, sometimes off-label works just fine.

Oh dear, now we are all going to be out looking for used Royer mic's for an ortho project!

 

[wualta]

Quote:

Just a guess but I'd bet that the drivers in just about any headphone would measure as a tweeter at 1 meter.  

Exactly. It's the 4-pi speaker-in-a-tree effect. But I'd imagine most tweeters don't have the excursion capability to produce bass anyway. They're engineered to be tweeters and nothing else.
 
Quote:

Oh dear, now we are all going to be out looking for used Royer mic's for an ortho project!

Uh oh. This takes us all the way back to the beginning of the thread and setmenu's ribbon headphone project. I wonder whatever became of that.

 

[Hutnicks]

Quote:

Exactly. It's the 4-pi speaker-in-a-tree effect. But I'd imagine most tweeters don't have the excursion capability to produce bass anyway. They're engineered to be tweeters and nothing else.
 
Uh oh. This takes us all the way back to the beginning of the thread and setmenu's ribbon headphone project. I wonder whatever became of that.

I'd love to hear how that worked (or didn't) out. Now if someone could just shrink down the Apogee Studio Duetta II to headphone size....

 

[MuZo2]

Quote:

But I'd imagine most tweeters don't have the excursion capability to produce bass anyway. They're engineered to be tweeters and nothing else.

Now thats what I was wondering what makes them tweeters? If we use same diaphragm in different magnet array(push pull) will that help? or diaphragm are too tight to produce the low end?

 

[wualta]

Quote:

Now thats what I was wondering what makes them tweeters? If we use same diaphragm in different magnet array(push pull) will that help? or diaphragm are too tight to produce the low end?

If you're talking about the SFI tweeters, the diaphragms are most likely the same, and they're already push-pull, but since the back magnet is not perforated, the air trapped in there acts like a stiff spring, making the diaphragm tension effectively higher. That, plus the reflex action of that solid back plate means lots of treble, very little bass. One very brave orthsketeer disassembled a bunch of SFI tweeters and put the perforated magnets on both sides and reported success, but it's rather a large PITA to do that. But if one is desperate..
 
In what I wrote, I was thinking of conventional dome tweeters, the kind you'd find in regular speakers. Even if they had excursion (which would make them prone to decentering), the coil and magnet structure assumes virtually no movement, so the magnetic flux is highly focused on a tiny coil that barely moves, which does wonders for efficiency.

 

[MuZo2]

What do you think, would this configuration work for SFI diaphragms.
 

 

[vid]

Ravaging the HOK 80-1.
 

 

 

 
Observations. The magnet holes align in the middle, but not on the outer edge. Why? Taping up all blocked holes on the front reduces the treble quite a bit in volume, but not much else in the spectrum. Also, the coil looks coppery on one side of the driver and silvery on the other. Not sure if normal. (Guessing copper is the color of the diaphragm material, then.)

 

[vid]

The other driver.
 

 
So...... you think the sonic improvements later in HOK v. 2 had anything to do with not aligning the magnets in this sort of way?

 

[bareyb]

I think it's time to post this again.
 

 

 

[vid]

Had a listen to the newest HP-50S mod again. Already liked it yesterday, and still strikes me as very nice today. I could swear the soundstage deepened just a bit as the driver was moved slightly further away from the ear by the wool disc. Can't hear any nasty spikes in the response, though looking at the graph, the level might be a bit high just at the edge of my hearing around 15-16 kHz. The only complaint I have is a somewhat sizzly treble, not quite realistic. Also, no sub-bass below 50 or 40 Hz. Other than that, an impressive level of detail without sounding trebly, and an overall neutrality over much of the audible spectrum.

 

[wualta]

Quote:

What do you think, would this configuration work for SFI diaphragms.
 

Without going back to the Yamaha drawings to check, it looks good to me. Did you find a source of magnets like that?
 
 
Quote:

Ravaging the HOK 80-1.
 
 

 
Observations. The magnet holes align in the middle, but not on the outer edge. Why? ...

Looks pretty ravagey to me. Now we know it's a pleated diaphragm, so thanks for doing that. As for why HOK (and others) sometimes made drivers where the holes lined up perfectly and sometimes not, I don't know. Since you said you notice a change in the sound with a slight alignment, I was thinking hey, maybe they're doing it to tweak the FR of drivers so they match more closely, but that sounds too crazy to be true.
 
Oh, and it has occurred to me that if Royer can make powered ribbon mics and KRK and Prodipe can make powered speakers, why not powered headphones with motional feedback and dedicated EQ and the whole works?

 

[Hutnicks]

Quote:

Without going back to the Yamaha drawings to check, it looks good to me. Did you find a source of magnets like that?
 
 
Looks pretty ravagey to me. Now we know it's a pleated diaphragm, so thanks for doing that. As for why HOK (and others) sometimes made drivers where the holes lined up perfectly and sometimes not, I don't know. Since you said you notice a change in the sound with a slight alignment, I was thinking hey, maybe they're doing it to tweak the FR of drivers so they match more closely, but that sounds too crazy to be true.
 
Oh, and it has occurred to me that if Royer can make powered ribbon mics and KRK and Prodipe can make powered speakers, why not powered headphones with motional feedback and dedicated EQ and the whole works?

Well er, um, size springs leapingly to mind. Not too sure I'd like to go back to the 70's with massive cans with knobs and geegaws sticking out all over
 
Allthough an amp the size of an e5 should be easy enough to integrate. Then again you have any add on's dictating the size and shape of your acoustics (think wireless headphones.....eek).
 
On the lined up magnet hole issue. I would be surprised if there was the level of hand made production involved which would allow for various alignment adjustments. I would think that would be cost prohibitive