Head-Fi.org › Forums › Equipment Forums › Headphones (full-size) › Oppo PM-1 Planar Magnetic Headphone Impressions Thread
New Posts  All Forums:Forum Nav:

Oppo PM-1 Planar Magnetic Headphone Impressions Thread - Page 16

post #226 of 3023
Quote:
Originally Posted by bigshot View Post

I'm not a headphones guy. I'm a speakers guy. I've never found any headphones that came close to a speaker setup with a carefully equalized response and good room acoustics. I was kind of surprised Oppo chose me for their beta group, but after I started working with them, I figured out why they chose me.

I work in the entertainment business, and I've supervised recording sessions and sound mixes as part of my duties. I always admired the quality of sound I heard in first class recording studios and mixing stages, and wanted to recreate that in my home. I would ask the head engineers at the studios questions to find out what it would take to achieve that and filed the info away in my head for when I got a house where I could build a first class listening room.

I recently got that opportunity when I moved into a new house that had a room that was absolutely perfect for a screening room/listening room. I assembled a first class set of speakers and spent about four months carefully EQing and balancing the levels by ear using acoustic music. The goal was accuracy and realism... a stone flat frequency response
 

i kind of took your post as advertisement at first so i had to question.  I see now what you're talking about. Sorry.  Oppo appreciated that over time you found that speakers need a flat response to sound accurate (basically the definition.)  Then they had you measure them for them right?

post #227 of 3023

Must say, a SINGLE DRIVER capable of producing a perfectly flat response in the audible range is a pretty big deal.  Im guessing since they've been able to do this they probably will be making a speaker soon enough that will blow the market away.

post #228 of 3023
Quote:
Originally Posted by Beagle View Post

This is the oddest appreciation thread I've ever seen blink.gif

yeah. another one for the sound science forum i guess.
post #229 of 3023
Quote:
Originally Posted by DoctaCosmos View Post
 

Must say, a SINGLE DRIVER capable of producing a perfectly flat response in the audible range is a pretty big deal.  Im guessing since they've been able to do this they probably will be making a speaker soon enough that will blow the market away.

 

The designer of the PM-1 is Igor Levitsky who is best known as the designer of BG Radia's Planar Magnetic speakers.

http://www.bgcorp.com/planar-magnetic.html

post #230 of 3023
Quote:
Originally Posted by tinyman392 View Post
 

No matter how accurate you want to say you are, you just can't place a bound around like that because of the fact that the human hearing simply doesn't function like that.

 

In the past, I've done experiments with equalizers to determine my own thresholds of audibility and to train myself to recognize specific frequencies. Your mileage on that may vary. Take that for what you want. But to evaluate the response of the Oppos, I used a signal generator and did sweeps a couple of octaves at a time and evened them out using an equalizer. Then I took note of my equalizer settings to determine the size of the bumps and dips. I checked my results against a second set of ears that belonged to a professional sound mixer. That isn't a completely inaccurate way to determine the response of headphones. I'm not comparing my response measurements with any other headphones or any other method of measuring response. You can feel free to determine those things for yourself. All I'm saying is that the response of the Oppos is exactly the way I like... an audibly flat response for my ears.

post #231 of 3023
Quote:

Originally Posted by DoctaCosmos View Post

 

Oppo appreciated that over time you found that speakers need a flat response to sound accurate (basically the definition.)  Then they had you measure them for them right?

 

The Oppo folks looked around the internet to assemble a team of regular hifi nuts, not professional reviewers or web masters, who would help them fine tune their product for the audio market. My general area of interest is in frequency response. Other people on the team had other specialties and interests- some very technical, others very subjective in approach. We all got rounds of beta copies of the headphones and contributed our comments and corresponded with each other in a private forum. There were about 10 or 12 of us I guess, and we got three beta versions to evaluate over the past 5 or 6 months, each with modifications based on our comments and the notes from the design crew at Oppo. They sent me a nice box of Sees candy at Christmas, and this week when the beta stage was over, they sent me a complimentary set of the retail shipping version of the headphones. That's how it worked. I'm not advertising. We have a thread here where people are interested in what's up with these cans, and I have been listening to them as they evolved for the past several months, so I am kicking in my thoughts.

post #232 of 3023
Quote:
Originally Posted by bigshot View Post

My general area of interest is in frequency response.

FR is love. FR is life.
post #233 of 3023
Quote:
Originally Posted by arnaud View Post

The equalizing by ear done by bigshot using his calibrated speaker is why I mentioned these phones should be renamed as BigShot-1 wink.gif.
 

 

LOL, it'll get abbreviated to BS-1.   :evil:

post #234 of 3023

Frequency measurements are one thing, but as far as measurements are concerned, I'm more interested in distortion measurements across the frequency spectrum.

post #235 of 3023
Quote:
Originally Posted by Edwood View Post
 

Frequency measurements are one thing, but as far as measurements are concerned, I'm more interested in distortion measurements across the frequency spectrum.

Decay plots can also be very telling.

post #236 of 3023
Quote:
Originally Posted by jerg View Post
 

I made a screencapture from Hifiguy's video:

 

 

 

 

This picture has me concerned.  Looks like a really tiny aperture opening for the driver.  I'm guessing the driver is circular and about the diameter out to the silver bezel ring on the right?  Very small ortho driver when you compare it to the competition like HifiMan and Audeze.  The sheer size of the drivers in many top end orthos is what gives them their famous, nearly electrostatic transparency and airiness.  I'm concerned that if the drivers on the PM-1 are really that small, they just won't have the same qualities.

 

But who knows, maybe they defy physics a little and sound huge. 

post #237 of 3023

Seriously curious about the drivers in these, is it that quarter sized part? If so that is a seriously tiny driver moving a ton of air for that sensitivity, I'm reallllly interested in it. Wanting to see some FR graphs and some more comparison reviews.

post #238 of 3023
The drivers are oval shaped and large. The outer gold ring is at the edge of the drivers. The photos don't show them clearly because there is a plastic plate over the top that channels the sound into the ear.

Edit: Specs say 85 x 69 mm
http://www.oppodigital.com/headphones-pm-1/
Edited by bigshot - 4/5/14 at 11:21pm
post #239 of 3023
Quote:
Originally Posted by Edwood View Post
 

 

This picture has me concerned.  Looks like a really tiny aperture opening for the driver.  I'm guessing the driver is circular and about the diameter out to the silver bezel ring on the right?  Very small ortho driver when you compare it to the competition like HifiMan and Audeze.  The sheer size of the drivers in many top end orthos is what gives them their famous, nearly electrostatic transparency and airiness.  I'm concerned that if the drivers on the PM-1 are really that small, they just won't have the same qualities.

 

 

 

The driver is the size of the yellow surface you see in the image.


The driver is also oval, not circular.

post #240 of 3023
Ah, they pulled an ultrasone on us? Humm, not sure that's great idea for transient response actually. The black color stuff is some sort of felt?
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphones (full-size)
Head-Fi.org › Forums › Equipment Forums › Headphones (full-size) › Oppo PM-1 Planar Magnetic Headphone Impressions Thread