Drop + THX Panda Review (headphone)

[General Direction]

I've used these for a bit with the newest firmware and an EQ applied through the SoundID app. That way they are reasonably good, at least way better than passive. Still the comfort is somewhat lacking and the sound is not as good as my other headphones.
I'm looking for a way to apply the Harman curve to the flat response setting on the newest firmware, but haven't found a base measurement for it yet.

 

[WickedInsignia]

When I tried a used OPPO PM3 briefly the sound was quite nice (as one would expect from Oratory1990's choice office headphone) but there was pressure in the jaw area. I searched it up and it seems this was a common issue that didn't reduce with wear. It was a fairly severe pressure that felt like it would affect circulation.
I wonder if this build suffers from the same problem?

Also that huge midrange dip is something. Wonder what the goal was there!

 

[Billy Budapest]

Panda vs PM3 on Sonarworks rig.

Why in the world did they screw with the PM3’s frequency response so badly? As one of the PM3’s beta testers, I was involved with tuning the sound and it took many many hours of listening by quite a few people over the good part of a year to get the sound “right” for a wide variety of music and with an array of different amplifiers. To take all that work and throw it all away? WTF was Drop thinking?

 

[WickedInsignia]

As one of the PM3’s beta testers, I was involved with tuning the sound and it took many many hours of listening by quite a few people over the good part of a year to get the sound “right” for a wide variety of music and with an array of different amplifiers.

This sounds interesting!! Please do let us know if you have a post/summary of these experiences anywhere.

 

[Billy Budapest]

This sounds interesting!! Please do let us know if you have a post/summary of these experiences anywhere.

Just on a private Oppo system and we are bound by NDA’s from discussing specifics. I can say that they were fun times with good people.

I can let you in on my big secret as to how to become a beta tester. It was really easy—I emailed customer service and I asked!

 

[Helicopter]

Sorry if I missed it, but what is THX about these besides the brand license expense reflected in the customer cost?

Compared to Bose, seems to me.these are worth maybe $50; compared to the $9 Sony, $4.

 

[WickedInsignia]

Sorry if I missed it, but what is THX about these besides the brand license expense reflected in the customer cost?

Looks like just the amplifier. Some tuning may have been done by THX on that end? The Razer Opus is also supposedly tuned with help by THX, and that received a good neutral sound score on Rtings.

 

[PeteL]

Sorry if I missed it, but what is THX about these besides the brand license expense reflected in the customer cost?

Compared to Bose, seems to me.these are worth maybe $50; compared to the $9 Sony, $4.

Thx designed the amp in it, nothing more, nothing less, and nothing to do with the current review neither since they are used passive

 

[PeteL]

Looks like just the amplifier. Some tuning may have been done by THX on that end? The Razer Opus is also supposedly tuned with help by THX, and that received a good neutral sound score on Rtings.
View attachment 129227

Do you have a source for that? Normally THX is not in the business of transducers, or mechanical « tuning » , they sell their amp modules to any manufacturers willing to pay for reference specced amplification, I’m. curious about this Razer relationship, that’s unusual.

 

[Andysu]

Headless Phanter. I guess the audience isn't listening with those headphones.

 

[WickedInsignia]

Do you have a source for that?

All here:
Razer Opus THX site page

Razer Opus on Rtings:
Here

 

[solderdude]

What's impressive in the PM3 (and thus also the Panda) is the sensitivity.
119dB/V for a planar means a phone can drive it to impressively loud levels.
Amir measured it at 117dB/V.
For planars only the LCD4-MX is more sensitive measured at 118dB/V by RAA and they measured the PM3 at 111dB/V.
The MX4 is spec'd at 122dB/V.

 

[raif71]

Another Lemon (and an expensive one) unmasked. Thank you Amir

 

[PeteL]

All here:
Razer Opus THX site page

Razer Opus on Rtings:
Here

Interesting, I didn’t know about this certification program, according to this, there is currently 5 THX certified headphones,
3 iems from 1more, A Razer IEM, and the Razor HP you refer too, This confirms the Drop is not THX certified, but it is indeed confusing for consumers since the THX logo can mean different things.
https://www.thx.com/product-finder/

 

[solderdude]

In this case it only means the amplifier inside the device is a THX AAA™ amplifier.
You don't need that 'tech' to make a good amplifier.

 

[PeteL]

In this case it only means the amplifier inside the device is a THX AAA™ amplifier.
You don't need that 'tech' to make a good amplifier.

Right you don't, but you need expertise, and you need time, The Lack off both would be the main reason manufacturers go to turn key solutions. Then there's the added easy marketing associated with THX logo, but it don't comes cheap. That's not worth it for this reason alone.

 

[Helicopter]

I am betting someone else would do an OEM amp with inaudibly similar performance for less money. I would get on the horn with a few Asian manufacturers and see what design options they have ready-to-go if I were making something like this.

 

[PeteL]

I am betting someone else would do an OEM amp with inaudibly similar performance for less money. I would get on the horn with a few Asian manufacturers and see what design options they have ready-to-go if I were making something like this.

It's happening all the time, but that's the whole idea of OEM, we'll never know that company X didn't design the amp in their headphones.

 

[staticV3]

@solderdude I've was wondering how to convert Amir's mVrms/94dBSPL spec to dBSPL/1Vrms, but I think I figured it out:

[Amir's mV]*2^x=1000
->solve for x
x*6
add result to 94

Is that correct? Is there perhaps an easier way?

 

[NTK]

@solderdude I've was wondering how to convert Amir's mVrms/94dBSPL spec to dBSPL/1Vrms, but I think I figured it out:

[Amir's mV]*2^x=1000
->solve for x
x*6
add result to 94

Is that correct? Is there perhaps an easier way?

I think this is the easier way to look at this mathematical problem. Say, Amir measured XYZ mVrms/94 dB SPL. So, how many dB is XYZ mV below 1 V? Answer is 20*log10(1000/XYZ). Add 94 to that and we have our dB SPL/Vrms sensitivity.

[Edit] I tried your method (first step), doesn't seem correct (or may be I've missed something). Added the condition that x > 0, looks more reasonable, but still seems incorrect.