[ericj]

Quote:

Originally Posted by wualta /img/forum/go_quote.gif Excellent. Most Ortho earpads turn up intact, unlike the Audio-Technica and Stax pads from the '70s and early '80s, but for those that don't, this is useful information, and it's great to have the velour option. .

Well, I object to pleather in general, and the high-gloss patent-leather-sheen of the original yamaha pads, I find exceptionally objectionable. I'm sure they're great for some people, but, bah.

The best of my two sets of ghetto yamahas came with pads that were merely half-flattened with about half of the shiny black finish worn off the pleather. I believe these pads are under my bed at the moment.

The other set were flat to the point of no cushion, and worn through in some spots. I threw them away.

Of course, this is a hazard of my ebay habits. I decline to purchase lots of yamaha orthos with pristine, shiny, patent-leather-looking pads.

So, having a pair of MDR-V200's in the junk bin to peel pads off of was good. Sony pleather in good condition is less objectionable than Yamaha pleather in bad condition. The Sennheiser pleather is better still, and the back of the sennheiser pads is a firm vinyl that should hold up well to being stuck and unstuck. The finish on the sony pleather starts to peel off pretty quickly with that kind of abuse.

I'm ordering a pile of HD485 cables and an HD650 cable from them this weekend, I'll have 'em add a pair of HD25 velours as well.

 

[ericj]

Quote:

Originally Posted by swt61 /img/forum/go_quote.gif Can I find stiff enough felt at most fabric stores, or should I be looking for an old felt hat in a second hand store?

I bought my damping felt at a JoAnn - I'm pretty sure that's a national chain. It's quite black, quite dense, less than an 8th of an inch thick. Wool/Rayon blend. Works well.

Unfortunately (well, fortunate becaue it was cheap), I bought it as a remnant, and i have no idea what maker or product it is.

 

[swt61]

Quote:

Originally Posted by ericj /img/forum/go_quote.gif I bought my damping felt at a JoAnn - I'm pretty sure that's a national chain. It's quite black, quite dense, less than an 8th of an inch thick. Wool/Rayon blend. Works well. Unfortunately (well, fortunate becaue it was cheap), I bought it as a remnant, and i have no idea what maker or product it is.

I have a JoAnn's nearby, I'll check there.

Quote:

Originally Posted by ericj /img/forum/go_quote.gif I'm ordering a pile of HD485 cables and an HD650 cable from them this weekend, I'll have 'em add a pair of HD25 velours as well.

Yeah I noticed today that the pads are the same size as the AKG K81DJ's, and I use the Senn. HD25 pads on those, so should be a good fit and nice and comfy. My pads are in pristine condition, as well as the rest of the headphones. If I didn't know better I'd swear they were made yesterday.

 

[Inkmo]

hey guys! Good to see folks in this thread again. What is the current situation with the ATH-2s? Did you get a damping solution that works? I haven't taken mine apart yet, but I think I have a general idea for what you're thinking will work with them...

 

[wualta]

Quote:

Originally Posted by swt61 Oh and my HP-1's arrived today! Not as dark as memory lead me to think they'd be.

No, they're pretty close to acceptable (except for the transient response) right out of the box, which is why I recommended them for people just wanting to get their feet wet and see what the fuss was about.

Quote:

Originally Posted by swt61 Can I find stiff enough felt at most fabric stores, or should I be looking for an old felt hat in a second hand store?

For the sake of experimentation I'd go for both. I got my cheap felt from a chain fabric store-- just walked in and asked for the thinnest-- make that cheapest-- felt they had, though now I'd ask for the densest. [UPDATE: Not so fast, wualta-- it turns out that the cheapest thinnest felt gets you very close and that premium felt damps most (not all!) isodynamics too much. What you want is something just slightly denser than the cheap acrylic felt.]

Hat felt is probably sized-- if it damps too much, it might help to wash out the sizing.


.

 

[JohnnySavant]

I'm pretty much a novice when it comes to hi-fi audio. I was going through some old stuff to put on eBay and I found a pair of Burwen PMB 8 Orthodynamic headphones. I had no idea what these were until I read this thread. They work fine, but aren't nearly as efficient as any of my modern headsets. No wonder--The impedance (DCR) measures around 165 ohms!

I can't sell them here because I'm a newbie anyone who's interested can look on eBay in the next few days.

 

[wualta]

Quote:

Originally Posted by JohnnySavant I'm pretty much a novice when it comes to hi-fi audio. I was going through some old stuff to put on eBay and I found a pair of Burwen PMB 8 Orthodynamic headphones.

Allow me to be the first to say: Whoa!

and also: Have you by some vanishingly small chance got an owner's manual or box or anything with specifications?

Photos?



Quote:

Originally Posted by JohnnySavant They work fine, but aren't nearly as efficient as any of my modern headsets. No wonder--The impedance (DCR) measures around 165 ohms!

In the case of isodynamics, the DCR (DC resistance) and impedance (think of it as resistance to AC current) are about the same. Sounds like they're in the ballpark with the Yamahas.

Remember, efficiency isn't the same thing as the inverse of impedance. You could have very efficient high-impedance 'phones or very inefficient low-impedance ones. The old isodynamics had to contend with mediocre magnets, so they were both medium-high impedance and inefficient. Not a problem for the home audio gear of the day, when the low-impedance chip amp was less than a gleam in Signetics' eye.


Quote:

Originally Posted by JohnnySavant anyone who's interested can look on eBay in the next few days.

Whoop! We'll be there, if only to ogle the photos. Any chance of a preview?

 

[facelvega]

They're up.

From the first glance at the pictures, I'm interested to see that although the headband assembly is the same one MB used and still uses on all its upper-level dynamic headphones (apart from the fancy headband itself), the earpieces are unlike any of the dynamic MB models I've seen. Sadly, they have a beyer-style two point hinged aluminum mount, and not the delightful MB five-point cardamatic suspension which for some amazing reason nobody on head-fi seems to know is perhaps the most comfortable headphone design ever made. It looks like the earpieces might be just big enough to accomodate the same driver that was used in the PMB100.

 

[swt61]

Those are certainly interesting looking. I'll have to keep tabs on them.

I should be recabling my HP-1's this week. This will be my very first recable ever, and I'm not at all familiar with a soldering iron. I've got some great Head-Fiers feeding me advice though, and I'm making them very simple. No laughing when I post pics. I'll try to get some felt this week as well, and may even have some impressions late in the week or this weekend.

 

[wualta]

Quote:

Originally Posted by facelvega They're up.

And... they're gone. Were they even up for a whole day?

Quote:

Originally Posted by facelvega From the pictures, I'm interested to see that the earpieces are unlike any of the dynamic MB models I've seen. It looks like the earpieces might be just big enough to accommodate the same driver that was used in the PMB100.

They appear to have earpads similar to the B&0 U70. The pleather flakes off, leaving white cloth. And as we know, there's a connection between the U70, the Burwens and MB Quart.

Note the circumferential vents, just like the A-T OEM'd Realistic Pro 30 and similar to the vents on the early Yamahas.

Is the PMB driver bigger than the 55mm Yamahas? That would get my attention right away.

 

[facelvega]

Quote:

Originally Posted by wualta /img/forum/go_quote.gif Is the PMB driver bigger than the 55mm Yamahas? That would get my attention right away.

PMB100 has 55mm drivers, measured by the magnets.

 

[daveDerek]

is there a concise description of the whole yamaha line that discusses the similarities and differences amongst them (with perhaps the history, time line, and pricing thrown in for good measure)?

 

[facelvega]

Quote:

Originally Posted by daveDerek /img/forum/go_quote.gif is there a concise description of the whole yamaha line that discusses the similarities and differences amongst them (with perhaps the history, time line, and pricing thrown in for good measure)?

this thread is it, along with a couple of other easily searchable threads as appendices. I know of no good survey on the net outside of head-fi.

 

[ericj]

There's that german hifi site, but some of their info is demonstrably incorrect.

 

[swt61]

Today my XLR connectors came in, and I was able to finish my recable on the HP-1's. I did the felt damping mod yesterday, but had no way to listen until now. I was a bit unsure of the mod, because the felt I had was kind of thin, so I used two pieces, and I really had to push down on the trim ring to get the screws back in. It lays nice and flat with the screws in however. The foam was in pristine shape just like the rest of these headphones, and the foam is bright yellow, as well as the felt I found.

I've mentioned before that I was having two Darkvoice 336i's modded into a pair of balanced monoblocks to drive my AKG K340's. Fitz was well into the mod when I stumbled on the Yamahas in the for sale forum. I had no memory of how hungry the Ortho's were, and just hoped they'd pair well with the new amps.

OK onto the sound. As soon as I got the XLR's soldered onto the new cables, I plugged them in to the amps and put in Alison Krauss' new album. First reaction...I was far from impressed with the mod. The treble extension sounded worse not better, and there was an even darker sound than before.

Here's the catch however...what I didn't mention was that when I took the HP-1's apart the other day, I realized that the pads were the same diameter as my stock K81DJ pads that I had replaced w/velour pads. So before glueing any pads down I stuck these pads in place for my first listen. Not so hot.
Hoping the stock much thinner pads might be a better match I then switched them out temporarily, and cued up Alison again.

HOLY CRAP!!!

This is phenominal! Gone is the darkness...completely. The treble extension is just beautiful. The thicker velour backed pads of the K81DJ with it's attached fabric screen was a horrible mismatch for the HP-1's. All the great qualities of the Yamaha's are still there in spades...the beautiful smoothness, the tight, full, well controlled bass. Only now the Yamaha's weaker characteristics have vanished. The darkness is gone, the rolled of treble is history. These instantly went from good to incredibly good.

The only thing I can't tell you is how much of the improvement is due to the felt mod, and how much is due to the balancing. As many of you have posted about the great improvement with the felt mod, I'm guessing that has a lot to do with the new sound. I can't rule out that balancing isn't improving things quite a bit though. Once my new faceplates and single stepped attenuator are installed on my amps (maybe 2 months or so), I'll have combo jacks on the front and SE as well as XLR inputs on the back, so I'll be able to use my XLR-1/4" TRS adaptor and tell you how the balancing effects things.

I'm just amazed at the improvement though. Actually my jaw all but hit the floor after switching pads! Needless to say the stock (very nice condition) pads were permanently attached with 3M double sided trim tape (special ordered for attaching wood trim).

Please try to refrain from any chuckles at my recable. It was not only my first attempt, but my first time soldering period. The solder joints came out beautiful thanks to some very good instruction from warrior05. I realize the heatshrink choices look a little odd, but I didn't know how to include the wooden piece otherwise. Now that I'm more comfortable with the process I may redo these at some point. They sound incredible though. The dual amps are not overkill either. The Ortho's use the same setting as my power hungry K340's, and that gives me almost exactly the same volume. They love the juice!

I have to say all told I have just a few dollars over a hundred in these with shipping and the XLR connectors. The rest of the cabling supplies were graciously donated by Fitz who was too busy with other orders to recable these as quickly as I wanted them. I feel like I just won the headphone lottery. These are a stunning sounding set of cans, and a great addition to my now not so lonely vintage stable. Between these and my K340's I'm one very happy guy!

Thanks Ryan and Scott, you guys are gold! Thanks to daveDerek for selling these to me, and thanks to wualta, ericj and the rest of the Ortho guys for turning me onto this mod.