Orthodynamic Roundup

[FooTemps]

wualta >> yeah, the transplant is somewhat of a mixed success IMO. Everything sounded great except for the slam that the original YH-100 had in spades. I was trying to match that amount of bass impact while retaining the other good qualities. I have an idea of what to do, but as of right now I don't have the materials to do it.

Audiocats and I will meet up sometime next weekend to work on tweaks and such. He wants to hear the headphones stock which was the main reason for the conversion back to original housings. Hopefully we'll get around to listening to stock, 1.5, QP transplant, and custom housing mock-ups.

Yeah, I'm going to use the QP headband and build my own housing. I'm going to try multiple mock-ups but right now I'm planning on making a t50 like housing with no back chamber.

 

[spritzer]

Quote:

Originally Posted by wualta /img/forum/go_quote.gif Ah, the ever-faithful KA-7100. Perhaps not the cleanest amp ever built, but one with a lotta heart.

The KA-7100 does have some major design issues such as the speaker outputs and AC running next to each other. It was cheap though as my dad bought it new and I "borrowed it".

Quote:

Originally Posted by wualta /img/forum/go_quote.gif It was my fondest wish.

In direct comparison with the HD600 the T-50 is clearly superior with better bass, treble and no diffuse EQ in sight. The way the drivers are mounted shows a good understanding of planar nature and realization of what is needed to make them shine. A recable is clearly needed but other then that they are restoring my faith in magnets and their use in transducer design.

Quote:

Originally Posted by wualta /img/forum/go_quote.gif Knowing how you prefer your SR-X, I'm not surprised. I can imagine that pulling out the damping pad would lower the resonant frequency a little and undamp the bass too, but having more backwave on the loose would make the earpad seal more critical. Do you find that to be the case?

Actually, I've put the damping pads back into all of my SR-X Mk3's because the tunnel effect was driving me nuts. If there ever was a headphone that needed a nice wooden housing, then the SR-X is it.

If I break the seal, the bass becomes a bloated mess so the theory stands up in practice. I'm all for the use of damping when you have to control the behavior of the drivers but with the T-50 it isn't really needed. The subtle HF etch doesn't really bother me and the soundstage and bass more then makes up for it.

 

[unbiased]

I just noticed my old Yamaha HP-2 has buzz on some low frequecy bass notes now... damn.
sorry been away from this thread for awhile whilst I ramped up playing with my new dynamic type headphones. These still sound so natural. Shame they don't make them anymore.

 

[AudioCats]

Quote:

Originally Posted by FooTemps /img/forum/go_quote.gif I'm going to try multiple mock-ups but right now I'm planning on making a t50 like housing with no back chamber.

or you can try putting the driver into Accura housing and see what happens.
The SR-55x (Accura housing + QP drivers) has pretty clean sound and quite a bit more bass than the 55x. Looks like the Accura housings boost bass better than the 55x's.


The Accura drivers are 55mm too, so the baffle should fit YH drivers ok.



.

 

[wualta]

Quote:

Originally Posted by JadeEast /img/forum/go_quote.gif While not really headphone related I picked up a pair of Monsoon multimedia speakers for free at a yard sale. A head speaker was my first thought when I saw the Monsoons.

Yeah, they're a little heavy for headspeakers, but you can do some fun things with them. They also need equalization to flatten out. Which model did you get?

By the way, if you have one of the models with the bigger panel (700/702/1000) note that the back of each panel has... a damping pad. Again, it's not enough to flatten the response, but the need was recognized. Plus they expressly wanted max backwave, so it's another example of a tradeoff.


Quote:

Originally Posted by JadeEast /img/forum/go_quote.gif As far as cans go I've reduced the reflex dot on the Pro-30s and they sound a bit less hard. Over all I would say that removing the metal badge on them is a worthwhile mod..

Good to hear, both. I'll give the cap popoff a try.

Quote:

Originally Posted by JadeEast /img/forum/go_quote.gif It's becoming more and more obvious that I need an amp with some balls or eggs that is headphone friendly. Kind of curious about the Yamaha amps that are labeled for use with orthodynamic use.

The Yamaha amps/receivers so labeled are nothing special beyond their normal Yamacompetence. They were trying to sell headphones. I doubt very much that there's anything in those headphone outs that isn't in other good amps/ceevers.

Vintage amps are lots of fun, and I especially like the MOSFET jobs, but for about the same money you can get one of the Panasonic digital receivers. Get an old headphone junction box like the Pioneer I mentioned earlier and you can go either headphone out or speaker out. Plenty of oomph using the latter method particularly.

I've bestirred myself and bought some Fluval (Hagen) fishfoam so as to practice what I preach. Results tomorrow. Well, later today.

Ericj, good to hear you found an amp-- portable?-- that will juice the HOK. If it'll do that, it'll drive anything.

.

 

[FooTemps]

Random idea inspired by: http://www.thecoolhunter.net/design/...or-listening-/

I was just originally thinking of making my mock ups for the housings out of cardboard, but I'm thinking of actually using cardboard as the final housing due to the damping properties. Having the housing serve as a damping system is a pretty interesting idea IMO. And yes, I would use construction techniques similar to the link. The only difference would be that I would stack (glue) the cardboard perpendicular to the driver.

 

[facelvega]

Quote:

Originally Posted by spritzer /img/forum/go_quote.gif If there ever was a headphone that needed a nice wooden housing, then the SR-X is it.

more subliminal suggestion for Steve, eh?

Quote:

Originally Posted by unbiased /img/forum/go_quote.gif I just noticed my old Yamaha HP-2 has buzz on some low frequecy bass notes now... damn. sorry been away from this thread for awhile whilst I ramped up playing with my new dynamic type headphones. These still sound so natural. Shame they don't make them anymore.

Try a different amp/source-- weak amplification can turn bass to buzz with orthos.

 

[AudioCats]

has there even been any "behind the head" neck band style ortho?

 

[wualta]

I like the idea of making a nonresonant prototyping mule from corrugated cardboard. The problem will be making it airtight where you want it to be.

As for the buzz, it could be lots of things but there's one thing we know it can't be: a decentered dynamic driver.

FacelVega may well be correct in saying Unbiased is hearing his amp clip severely on a bass spike. There's really not much in a normal Ortho driver that could buzz, unless Unbiased has an HP-2 version of EricJ's twisty YH-2 drivers, ie, one that was made wrong at the factory.

If an amp or a headphone output runs out of reserve power, bass notes will go splat! instead of boom.

I also wonder if some crumbly old foam is loose in the earcup.

Unbiased, are you willing to disassemble your HP-2?

.

 

[FooTemps]

wualta >> The first prototype is going to be a completely open model, front and back. It's just going to be heavily reliant on the damping properties. The next more complicated prototype I want to make is going to use two different orientations of slices. There will be parallel stacked pieces for the baffle and surrounding the driver, then behind the driver would be perpendicular. I'm thinking that the design would actually not only damp the backwave, but channel it away from the ear.

Anyone know of any rendering programs in which I could slice shapes I make into 2 or 3mm pieces so I can print out cutting templates? I am NOT going to do the calculus to get the measurements for every piece, lol.

 

[wualta]

Can't help you with the CAD program to draw the slices, but cardboard can do the job. A childhood friend who now works for Bose (!) once built a speaker enclosure out of cardboard which proved to be every bit as capable of holding moderate amounts of bass pressure as a wooden one. As you've said, the trick is to orient the slices along the axis where they're most strong.

Having said that, I will say that in my opinion the talk of enclosures resonating like crazy and coloring the sound of certain headphones to often be very much overblown, especially when the headphones in question are older and made of substantial (read: heavy) materials. Undamped isotropic materials that are not dense but which are stiff, which we do find in modern headphones as manufacturers try to make them lightweight, will resonate or be acoustically transparent at certain frequencies, and can/will color the sound.

So it's an interesting problem. Carboard resonates too (scratch on a cardboard box), but can easily be damped. Keep us up on the progress of your project.

 

[spritzer]

Quote:

Originally Posted by facelvega /img/forum/go_quote.gif more subliminal suggestion for Steve, eh?

Me, never...

 

[ericj]

Quote:

Originally Posted by wualta /img/forum/go_quote.gif I also wonder if some crumbly old foam is loose in the earcup.

That's my guess, actually. But there's a chance that the HP-2 has better foam in it.

 

[swt61]

Quote:

Originally Posted by wualta /img/forum/go_quote.gif I like the idea of making a nonresonant prototyping mule from corrugated cardboard. The problem will be making it airtight where you want it to be.

I'd use NP-1. It's available at most home improvement stores, but you'll need a good quality caulking gun, because it's thick stuff. Also keep some thinner handy, because you will get it on your hands.

Quote:

Originally Posted by facelvega /img/forum/go_quote.gif more subliminal suggestion for Steve, eh?

LOL! I would consider it, but ATM I have way too many projects lined up, with my own MKII Donuts at the top of the list. I just received the wood Friday, and should start soon. Also warrior05 and I are collaborating on our own versions of the V-Dock. I'm doing our woodwork, and he's doing our wiring and soldering. Then lots of trim for various audio pieces.

Oh and wualta the pads got mailed this morning.

 

[FooTemps]

swt61 >> are you talking about that polyurethane sealant stuff? How easy is it to handle that stuff?