Set 6:

Fostex T50RP Anaxilus modified, Koss DJ100 (by request)

Fostex T50RP light mods

These are not modified off the same set measured above, so it would not necessarily be a good idea to compare these with those. I believe the stock Fostex measured above went to LFF for mods. I will get those in later for another measurement. I need to make another visualization tool better see the decay at specific frequencies. Finally, maybe Anaxilus can chime in on exactly what he did.

1. Felt removed from front of driver
2. K271 paddeds added
3. Foam from vent removed

Blue - L channel - minor tweaks

Purple -  R channel - minor tweaks

Green - L channel stock

Red - R channel stock

Koss DJ100

When I put them on my head to first hear them, I really didn't want to measure these. By special request...

The HD800 can be dry sounding probably more because of its slight midrange dip with a sudden revenge of the treble. From the plots, the treble's hot, but it settles quickly. There's a broad ridge at 5kHz that settles fairly early too. All this is consistent with how I hear the HD800s.

The ESP950 measures good too. It doesn't seem to be as clean as the HD800 below 2k. A lot of that is probably due to enclosure resonance (cheap plastic) and reflections. I've noted very open phones tend to measure cleaner below 2k. But from 2k upward, the ESP950 settles very quickly. There are minor ridges throughout the treble, but they mostly in blue color that I don't think are really noticeable. The ESP950's frequency response - the back most plot at T=0, is awesome, and tonally, it sounds that way too.

As for LCD2s, I'm very curious myself. I can't seem to find anyone I actually know in person who still owns them. Anaxilus has a lead and is working on that for me right now - maybe in a week or so.

Quote:

Originally Posted by Reticuli2 

Thanks for the ESP950 waterfall. Wow. At less than half the price of an HD800, it's got possibly a superior response, even if its low-end decay and resonances are inferior. And that's with the stock amp, right? 

Those ESP950 measurements are from the POS stock amp. I'm listening to the ESP950s right now with an adapter to an SRM323 and it sounds very very nice. The relatively poor low-end <2k decay is IMO the result of the cheap enclosure. I will soon post ESP950 CSD and FR out of the SRM323. Not much of a difference.

Quote:

Originally Posted by Reticuli2 

I wonder what some of the good full-on Thunderpants would measure as with this technique. It's hard to believe most of those issues on the Fostex will be alleviated and I'm not sure Tyll's single frequency impulse response give enough information to verify that. 

 

Arnaud (and I, to a much lesser extent) is working with Tyll to see how much of his existing data is usable. Believe if or not, all we need is the impulse response (it actually has characteristics of white noise). Tyll may change his data capture methodology going forward and Arnaud will probably do the data crunching. I actually have some graphs from Tyll's data, but I don't want to post it because they are not comparable with mine and could lead to confusion.

 

Quote:

Originally Posted by Reticuli2 
 

The HD800's analytical character could be as simple as it having slighting more high frequency energy over neutral, especially over an even, smooth trend. I get a similar impression with Biamp DJ mixers over Allen & Heath and Ranes. A small 1-2dB even trend in favor of the highs over neutral (in the case of mixers, neutral is 0dB flat) is enough to do that. In the case of headphones, since it's the last in the chain you're going to get differing opinions as to whether it's analytical or "just right".  But you aren't going to hear anyone call it dark.

 

Exactly. IMO, it's more of an FR issue (despite Senn's insistent claims of "neutral"), although I feel the 5k broad ridge contributes to some "hardness". I would kill to have an HD800 with the FR of the ESP950, which is more or less a slightly downward tilted line from the bass to the treble - it doesn't get better than that. Still what Sennheiser did with the HD800 driver is quite an amazing achievement.

Set 7

ESP950 comparison from different amps: Koss vs SRM323.

I took multiple measurements rotating the cycle to ensure repeatable results.

• Not much difference at all, especially on the R channel.
• Overall, maybe a slightly more even decay and less spurious HF spikes from the SRM323.
• Notably more extended bass on L channel from SRM323 (see the partially obscured line in the back at 100Hz)

NOTE: Freq and time scale on these differ from most others.

from Koss Energizer

from STAX SRM-323

Impulse Response Click Here

What! Despite the measurements, they do sound better out of the 323 compared to the stock Koss box, but maybe it's just not enough for you.

Set 8

Fostex T50RP mods. Here are some real mods by LFF. You'll have ask LFF exactly what he did. The headphones did feel heavier and they had some heavy duty pads on them. He tuned these by ear and was horribly afraid they would measure badly. I should have stuck a DJ100 graph to freak him out.

Stock (of actual headphone before mods)

After LFF Mods

These modded T50s sound great. Bass sounded most excellent with great low-end extension, no midbass hump (passed my piano test), and tons of slam. The stock T50RP can sound hollow and tizzy. The mods result in a much smoother and tighter sound. As for the measurements, the decay is faster and much more uniform with is a lot less random spiky stuff.

I'll be throwing out some more related graphs in a bit... some will be interesting.

Continued Here.

T50RP Impulse Response

Red is the modded version. Impulse response is less compressed with a little more overshoot, but eventually settles more quickly.