Orthodynamic Roundup

[nick n]

An interesting bit of history that could have been. This regards the infamous Peter Belt. Found this in one of his newsletters that's available online discussing all sorts of things regarding sound. Yeah I know its sort of speakery but it has ortho relevance. Even talks about specific metals in cables sounding different, lead being best!
 
"All this illustrates the serious dilemma which faced Peter over 25 years ago when he began to discover just what could affect the sound. Should he continue developing his State of the Art, actively driven, orthodynamic tower speaker system, knowing the many different things within the listening environment which he was discovering could affect the sound ? Or, should he try to develop devices, techniques, treatments, which anyone, anywhere in the world could use to 'treat' both their environment and their existing equipment ?
As everyone now knows, Peter chose the latter path !!"
Also
"Chapter One.
Starting in 1981. During the making of his new 'state of the art' orthodynamic tower speaker system, Peter had found that when wiring the 108 orthodynamic drive units, the different coloured cabling he used gave different sounds."
 
Shame if you ask me. He could have at least finished that last project before diving completely into the "beltism tweaks" and abandoning most else.
Can only wonder what those particular units would have sounded like.
 
Link if you are interested. There's a bunch more on the ortho speakers systems mentioned .
http://www.belt.demon.co.uk/newsletter/vol0602/vol0602.html#%22There%20is%20more%20to%20it%20all%22

 

[wualta]

 

Quote:

"As everyone now knows, Peter chose the latter path !!"

 
Never trust any statement that ends in more than one exclamation point!! Yes, he could have been a planar-speaker pioneer with his 108-driver array. But that's a game that's hard to win. How many makers of affordable '70s-era speakers are still owned by their founders or by likeminded successors? How many successful mainstream makers of powered speakers are there? How many pioneers make money? In a way, I don't blame him deciding to sell the sizzle rather than the steak. 

 

[nick n]

Give it a shot it's a challenge. Thought you'd appreciate the DIY one
http://www.head-fi.org/t/577606/pictures-metaphoring-the-sound-of-your-headphones/540#post_8069953

 

[leeperry]

 

Give it a shot it's a challenge. Thought you'd appreciate the DIY one
http://www.head-fi.org/t/577606/pictures-metaphoring-the-sound-of-your-headphones/540#post_8069953

Hah, The HP-1 metaphor is priceless!
 

 
 

try the Acoustipak foam [..] The 3 layer Acousti will absorb quite a lot as it's denser layer is in the center and decoupled from the surface.  I found it to work pretty good, almost too good, and had to remove some because the sensitivity of the SFI's went way down. They make their own and have lab tests results you can check out.( it doesn't stink either )
 
I'm going to order another sheet ( 17 x 18 in ) I figure if you're going to all the trouble to get these things tuned do it with the best quality stuff you can at the time so it won't bother you later down the road.

 
I have to admit that you gave me buyer's remorse when I read your raving about the 7mm thick AcoustiPack acoustic foam as I had just bought a big patch of the 4mm version

 
But then I realized that it was simply the same foam, just sandwiched and that I could just sandwich it myself...and 7mm seemed a bit overkill at the time. Either way, I will be trying it soon

 
IME, cups resonances need to be contained but not completely eliminated. And the thicker the foam, the more restricted the air flow within the cups, hence the headstage depth and width too I believe.
 
BTW, I'm listening to the NOS anisotropic ferrite HP-1 as I'm typing this:
-trebles seem quite a bit darker than on my old sintered ferrite HP-1...I've tried it both on the fully AD797B pimped "Asus Essence One" and on the "Stello Eximus DP-1". The magical distorted mids don't really seem to be here either, OTOH I get seemingly thicker and tighter deep bass, hah

 
But I'm not a bass head, and I'm very much an ortho mids whore...so the way I'm hearing things atm, they might soon end up on the forum seeking a trade for a less polite sintered ferrite HP-1. I'll let them burn-in at fairly high volume for a few hours, though. The phone has been in its foamy box for decades, so let's be indulgent w/ old chaps ^^
 
I had a deal pending on a YH-100, but the seller recently told me that the trebles were dark as hell...to the point that he was wondering if it wasn't entirely faulty

 
I've also had some fellow ortho ninja telling me that the YH-100 indeed exhibited really veiled trebles and that neither of the several pairs he used to own seemed to show enough potential to warrant going through the trouble of modding them ...I now get to understand why the HE5LE could sound better than the HE5 to some and why the Beyer T1's argument of using the strongest magnets in the industry and yet not being a game ender by any stretch of the imagination might both have some truth to them...heavier magnets seem to provide thicker deep bass, but I don't care too much about bass duh.

 

[leeperry]

hummm...$300? seriously? http://www.ebay.com/itm/Used-Yamaha-Black-Orthodynamic-Headphones-HP-1-Original-Box-/180795679909
 
PS: OK, just A/B'ed both HP-1's, the sintered sounds less refined but I just love its THD in the mids and its most thrilling 3D sounding holographic SS. The aniso is too polite, the sintered is just far more fun to my ears...vocals are also far more upfront. I will let the aniso break-in in a corner for a few days

 

[wualta]

leeperry, can you hear the 2dB (or is it 3?) difference in efficiency?

 

[nick n]

Should the difference in colour be immediately obvious through the mesh of the earpads ( grey vs. smoother slight olive ) . I used a blindingly bright led flashlight and detected no olive tinges at all, and I can't remove the stock pads without tearing off their back padding.
I don't mind getting a top notch led flashlight but wanted to ask how immediate it was before I do. It appears grey and smooth too, so also wanted to know just how rough is the rough and the milling marks. Does it only show up in flash photography or by feeling it?
I'm irritated as to which I have. Maybe I'll have to buy another of each to compare to this 3rd one. That shouldn't cost much these days.

Oh thanks for the link Leeperry I'll just dig into the bottom of my worn out jeans pocket here and hmm let's see, ooops that was a moth, some fluff, an old receipt, couple pennies, a halls candy, oh yeah here it is: $400!

 
 
Did anyone ever get a rhyme or reason out of the serial numbers stamped underneath the top headband just above the left cup? 
Mine's in white writing.  What do those two you have say on them?

 

[vid]

Thanks for the tips, wualta. I'll experiment with something in front of the drivers.
 
In fact I already did. I heavy-handedly tried a paper dot and then a bit of felt. Not too much effect, but I'll try other variations.
 
It seems that it's much easier to accidentally deaden the treble elsewhere than to simply get rid of the hump where it's at. I've resorted to EQ-ing in the meantime. (I made a sanity check against the KOSS KSC75, and yes, the HOKs do sound better; yet ... not quite in the realm of honestly good, save for the mids.)
 
By the way, do certain areas on the surface of an ortho driver correspond to certain frequencies? Like highs in the middle, lows on the outer rim kind of stuff?
 
I'm a student of phonetics, and I should understand something about the basics of sound waves and a bit about how they travel, but I find them really difficult to conceptualize. It took me forever to realize how the frequencies on a power spectrum can co-exist at a single point on a waveform. (In the end I was confusing myself by thinking point and not window, but I still think the whole wave thing is an evil way of notation for sounds.)

 

[wualta]

 
Quote:

Should the difference in colour be immediately obvious through the mesh of the earpads ( grey vs. smoother slight olive ) . I used a blindingly bright led flashlight and detected no olive tinges at all.. I'm irritated as to which I have. 

 
My eyesight isn't very good anymore, so I too have had great difficulty telling a metal'd Ortho from a plain ferrite one without doing some disassembly. I hoped someone with better eyes could tell. Dang it. ...Possibly with a hardened-steel scriber tool. The ferrite will of course be much harder than the painted-steel "keeper" disc, and you might be able to feel the difference. Have you got a suspected/alleged Aniso HP-1 too?

 
Quote:

Originally Posted by vid /img/forum/go_quote.gif
 
1 ) I heavy-handedly tried a paper dot and then a bit of felt. Not too much effect, but I'll try other variations.
 
2 ) It seems that it's much easier to accidentally deaden the treble elsewhere than to simply get rid of the hump where it's at. I've resorted to EQ-ing in the meantime. (I made a sanity check against the KOSS KSC75, and yes, the HOKs do sound better; yet ... not quite in the realm of honestly good, save for the mids.)
 
3 ) By the way, do certain areas on the surface of an ortho driver correspond to certain frequencies? Like highs in the middle, lows on the outer rim kind of stuff?
 
4 ) I'm a student of phonetics, and I should understand something about the basics of sound waves and a bit about how they travel, but I find them really difficult to conceptualize. It took me forever to realize how the frequencies on a power spectrum can co-exist at a single point on a waveform. (In the end I was confusing myself by thinking point and not window, but I still think the whole wave thing is an evil way of notation for sounds.)

 
1 ) On the general principle of trying the simplest things first, instead of a "reverse dot", try a donut made of paper. Try funneling the sound straight at the ear rather than letting some sneak in from the top, where the ear has a sensitivity peak. Another strategy would be if-you-can't-squarsh-'em-join-'em; that is, try to raise the curve around the peak and then tweak the overall curve. But I'd like to know what's causing the peak in the first place.
 
2 ) If you've got a good parametric or third-octave EQ, it's obviously much easier to use it to get rid of a narrow peak. With a parametric, you can sweep back and forth to find the size and shape of the peak. Again, we haven't fixed the cause, but at least the 'phone is listenable in the meantime.
 
3 ) Lows in a Fostex , later-Yamaha and HiFiMan/Audeze driver perforce originate mostly in the center, where the diaphragm is least-constrained and thus its excursion is greatest (it forms that dome we keep referring to, like an electrostat does), but since bass is like water (or air pressure, which is what it is), it goes everywhere immediately, so the notion that some frequencies are produced  in certain predictable places has a technical grain of truth to it but in the big picture (represented by your ear) doesn't hold up. This is true as long as the diaphragm moves as a unit, with perfect, ideal uniformity. If different parts vibrated differently, we'd have a typical cone/dome dynamic, where makers have learned over the decades to let the center dome decouple from the rest of the diaphragm at high frequencies, where the limited rigidity of the diaphragm literally falls apart. Can't beat 'em? Join 'em. High quality dynamic drivers are designed to break up in this more or less predictable way with increasing frequency. If an ortho did this, the effect would be random and most likely wouldn't sound good. Does that mean that some people wouldn't prefer it? No, of course not, don't ask such silly questions.
 
4 ) Just as your eardrum is small compared to the size of any audible wavelength in air and can be considered a point whose function is to sample the air pressure, so any point on an ideally-behaving ortho or 'stat diaphragm tracks the movement of that eardrum-point, or, microphone-diaphragm-point. Points tracking points. Over time the points trace waveforms where one is a close analog of the other. That's all they have to do. Usually, yes, they fail in some way in the real world, and clever workarounds like the one I described above for fullrange dynamics are needed. But the results are good enough that we can say this simple model is also good enough. Am I understanding your question?
 
PS: Those of you with well-stocked university liberries might want to sneak into the depths and try to retrieve a copy of E.J. "Ted" Jordan's 1963 book Loudspeakers (Focal Press), which describes the decoupling-with-frequency strategy. The rest of us will have to be satisfied with bits: http://www.ejjordan.co.uk/book/

 

[nick n]

Quote:

 
I have to admit that you gave me buyer's remorse when I read your raving about the 7mm thick AcoustiPack acoustic foam as I had just bought a big patch of the 4mm version

 
But then I realized that it was simply the same foam, just sandwiched and that I could just sandwich it myself...and 7mm seemed a bit overkill at the time. Either way, I will be trying it soon

 

The difference between the 4 and 7 mm probably isn't much for thickness. Keep in mind though that the adhesive backing should act as a reflective surface, much the same as if you used adhesive backed stuff like felt to cover vents, it'll simply seal off and reflect things the same as a giant reflex dot. Learned that the hard way.
If you were planning on stacking by gumming the two together in the middle it won't be the same as the 3 layer stuff due to this, then how will you stick it to the surface
Either way the Acousti stuff is very well made and I like they have all the tech notes and designed it themselves. Check back in and tell us what you think of the stuff you grabbed. It's a massive sheet considering how much you'll need for headphones. If I get another sheet of the 3 layer I'll pm you and maybe we can do a swap of some to have the best of both worlds
 
 

 

[gurubhai]

Quote:

You should. You really should.
 

So, I gave it a go & something unexpected turned up so someone else would have to try the mod on low tuned drivers. The short version is that this particular pair of HP50 is not tuned low as is the norm.
 
Now the long version - This HP50 came with a mono plug so instead of recabling it to stereo, I simply transplanted the drivers to the PMB-80. I was surprised when I couldn't get much bass in that configuration since I expected a bass-heavy driver to atleast have more bass than PMB even without baffle sealing.Till yesterday, I hadn't listened to them in stock form.As it turns out these are nearly perfectly damped stock. On first listen I could find nothing wrong, so I did a side by side comparison with my T30 (my reference for damping) & only then I noticed a slight mid-bass bloom & blunting of transients.After a bit of experimentation, I settled on a single plugged hole as the damping scheme.

 
I have never come across such a well behaved yamaha driver before.

 
 

 

[leeperry]

 

leeperry, can you hear the 2dB (or is it 3?) difference in efficiency?

Yep, one is noticeably louder than the other.
 
After almost two days of blasting loud drum'n'bass music all day long, the SS seems to have opened up...Hallelujah brothers! Do orthos need to break-in in your experience? It sounded boxy and narrow as hell OOTB, but it's now gotten a lot more fun to listen to I gotta admit. It's essentially less distorted in the mids and has a much tighter deep bass response...there is no question that it's technically superior I think, I will let it break-in nicely. I'm currently listening to this CD, and it's pure bliss: http://www.amazon.com/Dancing-By-A-Rainbow/dp/B002LSYRK8
 

The difference between the 4 and 7 mm probably isn't much for thickness.

Well, it looks to me that the 8mm version is just 2x4mm stacked on one another:
 

Should the difference in colour be immediately obvious through the mesh of the earpads ( grey vs. smoother slight olive ) . I used a blindingly bright led flashlight and detected no olive tinges at all, and I can't remove the stock pads without tearing off their back padding.
I don't mind getting a top notch led flashlight but wanted to ask how immediate it was before I do. It appears grey and smooth too, so also wanted to know just how rough is the rough and the milling marks. Does it only show up in flash photography or by feeling it?
I'm irritated as to which I have. [..]
 
Did anyone ever get a rhyme or reason out of the serial numbers stamped underneath the top headband just above the left cup? 
Mine's in white writing.  What do those two you have say on them?

I am teh colorblind, so kinda similar colors look the same to me...I'll try to find some feminine assistance and will report back.
 
They both have a 6 figures serial# written in white on the headband inside.
 
PS: OK, that's my take on the metaphorical HP-1: http://www.head-fi.org/t/577606/pictures-metaphoring-the-sound-of-your-headphones/555#post_8074235

 

[leeperry]

Ah well, it's indeed rather obvious that the anisotropic drivers of that HP-1 are technologically more advanced than the older sintered...I've got an option on a YHE-50A(recabled to stereo) that's using 38mm isotropic drivers, just like the YHD-2 and 3. OTOH the YHD-1 is using 38mm anisotropic drivers.
 
The YH-100 is also aniso, only the 1K is using Cerium Cobalt...which I believe was the ancestor of neodymium, SONY also used it before going neo.
 
This PDF has a lot of infos about magnets, I'll read it carefully: www.allmagnetics.com/catalog/pmm_cat.pdf
 
so what's the next stop if you want better than anisotropic in an ortho phone w/o spending a grand? I'm reading too many QA problems on the Hifiman's to venture into a second hand HE5LE.
 
This aniso HP-1 is indeed more polite than the sintered, but it's hard to go back to its far more distorted mids and flabby bass in comparison. Also, the SS appears more "holographic" but I think it's due to a lack of control more than anything else. Life is about compromises, and the aniso HP-1 provides a very tight and percussive deep bass, a far cry from the T50RP haha

 
Beyer need to release Tesla orthos..that'd kill the stellar markup high-end ortho niche for good

 
PS: just A/B'ed them again w/ fresh ears, it's like FLAC Vs 96kbit MP3...less resolution(that makes it strongly emphasize vocals), bloated deep bass, smearing transients...it's a no return flight really

 
This sintered HP-1 will make a perfect guinea pig for my Takstar TS-671 transplant project.

 

[gurubhai]

@leepery : from your impressions it appears that aniso version is much better damped stock than the usual HP-1. Why don't you try some damping on the sintered HP-1 ?

 

[leeperry]

Well, damping is one thing...but the driver simply has less resolution to offer...I'm really not exaggerating when I'm saying that it's a FLAC Vs 96kbit/s MP3 situation. The MP3 effect sort of "blurs" the sound and makes the mids in the vocal spectrum more upfront. I now get to understand why many youngsters prefer lossy audio, it's easier to listen to...but more than "less analytical", you're simply listening to utter harmonic distortion and to a very colored sound.
 
The aniso could use damping, the sintered doesn't have the potential to my ears...I'll slap the latter into a Takstar, and if I like what I hear the aniso will follow...it'll only be a matter of 4 soldering joints at this point =)
 
So is there any missing link between the aniso HP-1 and the LCD-2?