Hifiman HE400/HE500 Re-Grilling Mod [56k dial-up users beware] - Page 2

Quote:

Originally Posted by wje 

 

You're more than welcome to join us at the headphone meet next weekend.     However, after the meet, I suspect I should be able to offer out the HE-400s to you for a week or so of listening. 

 

I made it by the Dollar Tree store this evening.  They haven't started to get in the majority of their back-to-school supplies.  I'll try again in a few weeks for the letter trays.

Perhaps try the pasta strainer / splatter man steel mesh instead? IMO it looks pretty cool on the HE400s, like I said it reminds me of SR007s, except much less refined of course lol.

Quote:

Originally Posted by wje 

 

I've actually purchased those great anti-splatter items in the past for the Grados.  The mesh was thin and stretched into the circular hoop, where it was squeezed to prevent it from coming loose.  When I cut the mesh out of the hoop, it was quite thin and wouldn't even suffice for a small 1.5" hole in the Grado cups.  Then again, the splatter guard was from K-Mart, which might have had a thing or two regarding the quality of it.

 

I think for a bit, I'll hold off on the project.  I've always told myself that the sound I heard from the HifiMANs made me content, and I didn't believe in any modifications.  So, I think I'll be true to my word for a while.  When I get into "modify" mode, it can become an endless obsession for perfection, tuning, etc.  Thus, it's easier at the moment to just use the headphones in the current state and enjoy the best of them.

The thinness factor of the mesh is a nonissue with this instance though, as the plastic securing ring holding the grill down actively applies pressure against the headphone housing when all the four tabs are in. I bought a curved splatter pan and a flat splatter screen today, and used the pan for the mesh cutouts, and it's actually kind of cool as there's a nice concave curvature to the grill areas now.

I agree with ya that the sound itself is very satisfactory, nothing "off" in the tonal balance or in terms of tightness that requires damping, but something that's mentioned everywhere is that the soundstage is not the most impressive, and incidentally this mod improves it noninvasively, that's why I went for it.

Today I made a new pair of grills using another type of mesh I cut out, this time from a steel mesh scrap bin.

Here they are (beside them are the stock grills, and the grills I made yesterday out of splatter pan steel mesh)

I also found the absolute BEST way to objectively evaluate the effects of any grills vs completely open-back:

Play a high bitrate pink noise, while hovering the grill in question on and off, but take note to minimize your hand movement because those also induce resonance.

Two things can be evaluated from this test method: 1) change in soundstage / "closed-ness", and 2) ringing / resonance induced by grill/fabric material.

Turns out my thinner antisplatter pan mesh made yesterday allows the soundstage to be maintained more, but induces the most ringing. My new grill made today kills the soundstage a bit more, but has the least ringing, the stock grills cause the soundstage to shrink the most out of the three types of grills on hand, and causes moderate ringing.

Seems like just the fabric along causes a very minor shrinkage of soundstage, but it's kind of unavoidable if we want dust protection. All that matters then is the type of mesh used, how much more it drags down the soundstage, as well as what level of ringing it induces.

Quote:

Originally Posted by paradoxper 

Pink noise is brilliant. I've been doing this for years. However anytime it's recommended people ignore or gawk at the idea. haha

Yeah, before I thought up using pink noise, I've been fairly subjectively trying to judge how the soundstage is changed by playing live concert music through them and doing the hover on/off with the grills, terribly subjective and biased.

Another surprise was that with pink noise I could actually notice the ringing the grills induce! That was previously impossible with just playing music and trying to judge, and it didn't even cross my mind that the ringing would be a variable thus.

Quote:

Originally Posted by paradoxper 

Could you not hear the ringing with music at all or was it just subtle? Did you try different music?

 

That'd be very interesting if it's only clearly (opposed to subtly) audible with pink noise rather than music.

It's extremely difficult to judge changes in sound with music, much easier to judge changes in soundstage. Nevertheless just because you can't discern it doesn't mean it is not present - it's just in the background muddying up the sound. The pink noise clears the distraction of the actual music so the ringing just pops out as an "extra noise" above the ground level pink noise.

This is especially clear with HE400s because without the grills, they have an extremely clean pink noise, I could not discern anything 'off' intrinsically.

Quote:

Originally Posted by paradoxper 

I guess I am just surprised it's inaudible with music. I am enjoying your experimentation. Kind of proving that it's not just the T50RP ortho 

that responds to modification.

It's not inaudible, I just wasn't paying attention to any ringing, that in combination of the masking effects of music on minor ringing means I was not able to discern them. If I intently listen and choose my music more carefully, maybe I could discern the ringing, but it's pointless at this point because the pink noise method is far more superior.

It's a shame though, the HE400s sound euphoric and so clean without any grills on. Anything in the path of the air at the back of the drivers really mess it up.

Quote:

Originally Posted by paradoxper 

Ah, ok got'cha. 

 

It'd be more exciting if others jumped on in. (Not to discredit your word) we just all hear differently. I believe you understand though.

It's an interesting testament though, if people are hesitant to mod their HE400s because they are so satisfied with its sound already. A bit paradoxical too...

I'm really hoping wje would try this when he gets the time. If not the mod, at least HE400 owners could try the pink noise test I suggested.