[notthedoctor]

I recently purchased a second hand pair sr80i's. I've been using them for about two weeks and have noticed on some songs, particularly with lower frequencies, there is a bit of distortion. It was only a few songs though, other songs that go down to the same frequencies don't have this problem. It's also not too common among most of the music I've been listening to, however its stopped me from enjoying the music that it does happen in.
 
I used Adobe Audition to view the spectral for some of these songs and they all meet the flac quality that they claim to be, so they haven't been transcoded from a different format or more specifically, a lower bitrate. 
 
I then thought that this was simply because of my lowly Realtek onboard audio, and i planned on getting a usb dac/amp anyway.
 
Then i was reading about Grado Grattle and i read about the tone tests another user did. First i did this one here http://www.audiocheck.net/audiotests_frequencychecklow.php
The tone in fact presented a rattle of sorts that lasted until around 60 hertz, then it went away. I played the same test again, no rattle. I played it a few times after that and nothing.
 
Then i played http://www.audiocheck.net/audiotests_frequencycheckhigh.php
What do you know? It rattled for about half of the test. I did it again and it was completely clear.
 
Then i went back to the low frequency test and i got the rattle again, this time however it stayed for the entire test. I played this multiple times after that and once or twice it rattled before clearing up. Going back to the high frequency one again the rattle was back. Testing back and forth there is always rattle in the opposite frequency once the sr80i "adjusts" to the one i just ran a few times. Usually it lasts for one test, maybe two. and sometimes doesn't last the whole test; so it seems to be slightly random. It also seems that if i play one test and then wait a few minutes and play it again the rattle returns, as if my waiting let it unadjust or something. However i can play both at the same time and after a few seconds they will both be clear.
 
The seller said the headphones came with just a few small scratches, and he said "nothing that changes the audio". I do find it odd now that he would add specifically that mentioning the audio. Now the bad part, I haven't checked yet how long i have until i can no longer return these however, I've already had them for a bit over two weeks... and during the time i thought it was just needing a proper dac, i may have vented the drivers just a bit, meaning i likely cant return these anyway.
 
I don't really know what it is even now, i only know what I've experienced so far and I've pretty much typed it all out. I'm hoping one of you Pro-Audiophiles will come along and tell me this is something with a quick 'n easy fix. "get the hair out of your drivers"

 

[notthedoctor]

I actually downloaded the same tests from that site and they play fine.... however there is still the problem with a lot of my songs giving me distortion. The distortion is generally with mid to low frequencies, but those same frequencies in other songs may be clear, it is also only present in some songs. As i said, the songs were quality tested and they all are what they're supposed to be. I don't see it just being the songs as well, since its present in around 40% of the music that i currently have, some bands are worse, some are better.
 
I'm using Foobar2000 along with Wasapi by the way.

 

[Aizura]

 
 
i may have vented the drivers just a bit, meaning i likely cant return these anyway.
 

What do you mean by this?

 

[notthedoctor]

I apologize, i was away over the weekend.
 

  What do you mean by this?

 
I am talking about the mod where one opens the cans and vents the holes in the back that are covered up. this mod is quite popular among grado modders from what i can tell, and if you search "grado venting" you should be able to find more information on it. I am quite new.

 

[Armaegis]

Have you done a visual check for hair/dirt/something in the driver? Especially if you vented the drivers, something may have gotten in. Or hair stuck in the front mesh. Etc.

 

[notthedoctor]

yeah, there actually was a hair or two in there, however i noticed when inspecting for hairs that the diaphragms had one or two small dents in them unfortunately. I've read about other people having similar dents and some say it doesn't seem to change the sound for the, though i imagine it does. I tried to suck out the dents and all I can see now is just one in the right driver, however both seem to still produce the distortion. 
 
I've also noticed that the distortion is only present in music that has a lot going on, generally conventional music with vocals. If i listen to something instrumental there is almost never distortion. The instrumental music i listen to is also a bit simpler, with fewer instruments playing at the same time. That information doesn't really help though if this is because of the dents

 

[Armaegis]

I've never heard high levels of distortion from dented drivers. Are you absolutely certain the dents aren't tears? Also check that the paper from the opened vents isn't flapping around.

 

[notthedoctor]

There are no visible tears. The dents that i saw are pretty much gone, save one. They didn't leave any visible damage behind. The loose fabric from the vents though is a good idea, I'm new to this but i feel it would make sense that they would be more likely to produce noise whith more congested music, but i had this problem before i vented the drivers. I only did so because i believed at the time it was because of my cheap onboard hardware. Still, i will be checking the vents for any loose fabric.

 

[Armaegis]

I've also had buzz coming from the internal wires rubbing against the housing or rear of the driver. A deeper rattle might also just be some weird and loose where the outer cup meets the inner cup/baffle. I'm just listing off whatever I can think of...

 

[notthedoctor]

I checked the holes that i vented, I made sure the fabric was tight and there wasn't anything loose sitting around in the holes. As expected unfortunately, it didn't help. It doesn't seem likely, but is there any chance it simply is just my cheap hardware?

 

[Armaegis]

Without being able to hear it, I'm out of guesses... sorry. I highly doubt it's a hardware/amplifier problem. 

 

[DaemonSire]

  Without being able to hear it, I'm out of guesses... sorry. I highly doubt it's a hardware/amplifier problem. 

Do you think it could be clipping that he is hearing?

 

[Armaegis]

Oh haha, I suppose that could be a possibility... though it doesn't seem consistent with some of his observations.

 

[notthedoctor]

I ruled clipping out by turning the volume down quite low and still finding it present. I did however take a loot at the spectrogram visualization in foobar and I realized something that i didn't really think about including before. This type of distortion isn't constant, rather, it presents itself in small and short "bursts" when certain frequencies are played. What confuses me though is if it has to do with something resonating at a certain frequency, or I don't know (I'm still new), then I imagine it should be present in all music played, yet i can't remember a single instrumental song that i have where i heard it. That also doesn't make a lot of sense considering that this varies per song; the places where the distortion appears don't contain similar frequencies throughout all of the songs, some being on the lower end, some on the higher, and the one i just tested now was right around the middle.
 
Maybe I'm observing incorrectly or presenting what i found incorrectly. This just makes it even more confusing for me, and it doesn't seem to make sense.