Orthodynamic Roundup - Page 1380

while we're living in the past with our ages old phones, yamie just released two Beats knock-offs:

http://uk.yamaha.com/en/products/audio-visual/headphones/hph-pro300_w/

http://uk.yamaha.com/en/products/audio-visual/headphones/hph-pro500_w/

I like how their FR is advertised as 20Hz-20kHz like back in the days, and not the bs 1Hz-100kHz like SONY does these days......some newbies actually seem to believe that it could make a difference.

Excellent news, I hope Yamaha will be able to sell enough of those to maybe reconsider mass producing orthos, since they still own the technology they used in the '70s and '80s. :)

They are probably using the same 40mm driver used in the Yamaha RH5-ma studio monitors, which is capable of excellent bass.

now... let's snipe a boken (cable) pair and SLAM IN them HP-50 drivers

The ringing of the Unipolar driver (of which you know if you search for a CSD plot) isn't due to the cup. The driver measures much the same completely naked as it does inside the cup. It's curious. The ringing looks like something continues to produce relatively even sound well after the signal is cut off (very slow decay on the ridges). But what?

I still want to see someone transplant some ortho drivers into those new Beyer COPs with the variable bass vents.

Armaegis I was wondering if Beyer sells that as a part, either way it has certainly crossed my mind also.  What are they worth roughly? Suppose I can empower myself and go look to see.

I know they came up in one of the deals threads under $200. I *think* there was one for $180 or $160.

It would be cool to see a picture of the Unipolar 2002 driver to see if Sennheiser made any changes to it vs. the 2000.

Quote:

Originally Posted by leeperry 

 

I liked your previous damping idea, wha was so wrong about it? One thing you could try is sanding off the foam from the "acoustic barrier" and use the latter only. That does wonders IME, mostly because that foam was meant to attenuate the whine of computers fans....not quite what we need.

Yes, it really does wonders!

I rubbed off the foam and by doing so I got a relatively even surface above the prone center in the back of the casing:

then I tried a felt donut and alternatively an acoustifoam donut to fill the outer circle of the cavity and it does not make a big difference (I like the foam more, it makes the sound a little more upfront). then comes an open cell foam disc and then a felt disc behind the driver. They come very close to the electrostats and have never been so good! The surface that covers the back of the case, with the center beeing more important, seems to have the highest influence on the openness and clarity of the HP-1 drivers.

Quote:

Originally Posted by wualta 

"Ringing" usually means a narrowband phenomenon, so I was a little puzzled at first. After looking at the CSD, that's what it is, just on several close-together frequencies (shades of the Bose Wave Radio!). My first thought was the same as Arnaud's. It's not so much  the diaphragm's mass itself that stores a lot of energy, it's the standing waves on that big empty symmetrical skating rink of a diaphragm. If there was a way to softly touch the diaphragm with, say, a cotton bud or a bit of Canadian Arctic Monkey Fuzz and probe around for hot spots, there might be a way to make a kind of acoustic snow fence to break up the standing waves. That's my guess, anyway. This is a problem that keeps designers of electrostatic speakers up nights, so it only seems right to try to apply it here. But it might be something else. Could the transformers be singing? Could that be tested by driving the diaphragms from, say, a Stax  box or amp?

 

Interesting problem, not to say painful-to-listen-to.

Something like this... http://www.youtube.com/watch?v=YedgubRZva8

(keep your finger on the volume dial)

Quote:

Originally Posted by Armaegis 

I still want to see someone transplant some ortho drivers into those new Beyer COPs with the variable bass vents.

I'm a bit sceptical about this solution for orthos. Then again, the unsuspected thing might work - history has taught us that one. But why not get an old AKG K180 for experiments where you can change the acoustics from front seat to 10th row?

MDR30, you got pictures of the Unipolar 2002 driver?

Quote:

Originally Posted by vid 

MDR30, you got pictures of the Unipolar 2002 driver?

Sorry to say no, I haven't been working on those for a year or so (having a Stax autumn). But there's a winter coming and if I'm inspired and get down to it I'll post pictures.

You guys keep on experimenting!