[skip129]

Just by the way, I have two other sets: HD455, and HD570. The HD570's actually make a sound like clipping, but I think it's more likely to be due to something loose, or a foreign object floating around somewhere. I haven't figured out how to open them up yet, but I've just hit the case quite hard a few times, and now the sound has gone, which lends credence to my theory that it's not actually clipping. The HD455's don't clip, however they don't have the same bass response as the other two, and I suspect that if I applied some EQ to reduce the bass such that the response mimicked the 455's, the 595's would not clip either. (I don't want to increase the sound level using the 455's so much that the bass starts to reach the level of the 595's, because I really *would* start to worry about damaging my hearing if I did that!)

Greg.

 

[skip129]

Quote:

Originally Posted by Lucabeer /img/forum/go_quote.gif I had the same clipping/distortion on bass with the HD-595 if I listened at a relatively high volume from a Pioneer non dedicated amplifier. I bought the Graham Slee Solo SRG headphone amp, and now I can turn the volume up so much that my ears are begging for mercy before any clipping starts...

Thankyou! That's very promising indeed - looks like that's my next step then.
This certainly tallies with my experience at the shop.

Greg.

 

[Lucabeer]

Just to give you an example...

On the Solo+HD595 I usually listen to music with the volume knob at 9-10 o' clock position. When I want it really loud, I turn it to 11. With some recordings which are a bit low in levels, almost at 12. But at 11-12, it's already way too loud (but no clipping): fun, but after an hour I have to stop. It's more or less the same level of sound pressure I was getting from the Pioneer when it started to clip on bass.

To get clipping/distortion with the Solo+HD595, I would have to turn the volume knob to the 3-4 o' clock position, a completely crazy and ear damaging sound pressure level... I tried it only once, because no one would ever listen to music so loud for more than 5 seconds. And even then, the distortion I heard was like the headphones had reached their structural limits, NOT like the amp was no longer able to control the drivers...

 

[skip129]

Thanks again.

In the shop, I had the headphone amp on 9'o clock - zero was about 7 o'clock from memory. This was very loud, but not painfully loud, and I could not hear clipping, but as I said, I think I could hear a bit of gentle distortion, which may for all I know have been in the recording itself - not sure.

The salesman set it to 8 o'clock and said that's the level he would listen at.
This was comfortable listening for me, but not loud.

Inspecting the waveform of the recording, it has been recorded loud. (not much headroom at all).
EDIT: Make that *zero* headroom - the source material does in fact reach 0dB.

(it's a direct digital loopback from an iTunes song, with iTunes level adjustment disabled, with no level adjustment elsewhere either) (I don't think this is the problem though - I can readily reproduce the clipping in other recordings as well).

Greg.

 

[skip129]

I've found the problem, and boy am I embarrassed.

My soundcard was overdriving the amp. When I reduced the output level of the soundcard, the harsh clipping disappeared, even after increasing the headphone volume to compensate. Doh. The soundcard has three different line level output modes, being -10dB, Consumer, and +4dB (professional).
With the latest drivers, there is no ability to set the level, or even inspect the level! I'm assuming that the driver must be configuring it for Consumer, which is a bit high for home equipment. It's a serious flaw in the driver but I should have paid more attention to this at the outset.

I do still have a different type of clipping/distortion, which I mainly notice when playing pure deep tones, such as the lower notes of a Rhodes electric piano. I bought a cheap dedicated headphone amp from a musical instrument shop today, and it seems to behave identically to the NAD amp in this respect. I may try to arrange a test of a good quality headphone amp at some stage, but I'm wondering whether I really am simply playing this kind of instrument too loudly for these headphones.

Greg.

 

[Uncle Erik]

You're probably still having an amplification issue. Headphones don't distort (at least the good ones don't) unless they're at unlistenable, ear bleeding levels.

The position of the volume knob is not the same from amp to amp or from headphone to headphone.

The output impedance of the amp compared to the impedance of the headphones tells you how much power can get through. I don't have it at hand, but there is a formula for this. One you know how power will transfer, take the amp's output power and calculate it with the sensitivity of the headphones. There's more to this and keep in mind that both headphone and amp impedance varies.

The short answer is that your headphones are demanding more power than your amp can give.

 

[m0ofassa]

Quote:

Originally Posted by Ryan Williams /img/forum/go_quote.gif I got some new HD 595s yesterday and I've noticed that when deep, loud bass comes up it sometimes seems to clip, and makes the characteristic popping sound. It's not a constant clipping, but it'll do it a few times during an explosion in a game like Battlefield 2142 for example (I haven't heard it during any music yet, but I've only had time to try one of my metal CDs). It's being driven first through my computer's X-Fi soundcard (not the Audigy-based one) and then through an AIWA hifi/amp (can get model/specs later if need be). 'Enhancements' such as the Crystalizer and CMSS3D/etc are disabled, and I've ran it in bit-matched mode to no avail. The volume isn't massively loud, and it does only seem to be the bass. Is there any known issue with the X-Fi that might cause this? Or do the headphones need 'breaking in'? It's worth noting that I didn't hear this with my old HD 212pro, but then the clarity was a lot more muddy then anyway. Thanks for any advice anyone can offer.

Turn down system volume to 75% instead of 100% (if you only have front L/R on). [size=xx-small]If i had to make a guess (this is speculation from personal experience)..... [/size]If you are running out of an analog output the x-fi will output volumes up to 24bit capabilities per channel even if you make it output 16bit/44.1khz. Not sure why. Your amp might not like it. Same thing hapened to me, turned down the x-fi and have not had a problem since.
edit: just read the thread. Turns out that I was correct. Yay me.

 

[skip129]

Quote:

Originally Posted by Uncle Erik /img/forum/go_quote.gif The short answer is that your headphones are demanding more power than your amp can give.

These low notes on the electric piano are very raw and pure. The headphones *feel* like they are being pushed very hard indeed, despite the fact that the actual perceived sound level isn't excruciating. I am sure that if the same signal level were output at a higher frequency, it then *would* be excrutiating.

My loudspeakers, which are reasonably good bookshelf speakers (plus a subwoofer) certainly distort readily with these low tones, even though it's not all that loud.

But I will try and test a good quality headphone amp - I am getting rather curious.

The cheap headphone amp I mentioned is going back - they don't have very good bass response - the headphone output of my NAD amp is better.

Greg.

 

[skip129]

I now have a Music Fidelity V-Can headphone amplifier. I still get distortion/clipping, but it always seems to be in the right headphone. I have reversed the headphones on my head, and reversed the left and right signals going into the amp - it's always the right headphone. I noticed when I had them plugged into the digital piano that it was also the right channel distorting too. I haven't yet tried further increasing the volume to see whether the other headphone distorts as well.

Just by the way, these headphones were on display, so I suppose they may have been abused. The obvious next step is to attempt to swap them for a new set. The shop I am dealing with has been great so far and I don't expect any problems with the swap.

Greg.

 

[Suntory_Times]

It sounds like the headphones where damages, or more to the point, it sounds like you may have some hearing damage in your right ear.

 

[skip129]

Quote:

Originally Posted by Suntory_Times /img/forum/go_quote.gif It sounds like the headphones where damages, or more to the point, it sounds like you may have some hearing damage in your right ear.

If it were my ear, the distortion would always be in my right *ear*, not the headphone marked "R". The distortion is only in the headphone marked "R" - that's why I did the head reversal test.

I now have a brand new set, and they are also distorting. I've only done a quick test, and so far there has only been distortion audible in the headphone marked "L".

I'm obviously driving them too hard. I am playing a very mellow (read: very sinusoidal) Rhodes electric piano sound, using lots of mid-low and low notes, quite loudly. I do not think this is typical of musical content - I am putting a lot of demand on the headphones.

Someone mentioned a bit earlier that when their HD595's distort, it sounds like the membranes are reaching the end of their extension - that's what my problem sounds like too.

I've given my store the *option* of recommending a more suitable set of headphones for my purposes. If not, I'll turn the volume down and move on.

Greg.

 

[skip129]

Note: my old HD570's are working fine - no distortion playing at the same level. (FWIW, anyway - they have a different response - more bass and treble than the HD595's - at least - that's how they *sound* to me)

Greg.

 

[skip129]

I've actually now decided to keep the HD595's, and just use them normally.

Note that the V-Can amp *may* have actually solved one problem. Playing a grand piano sound normally through the NAD headphone output, I occasionally noticed a bit of distortion when playing forcefully. I couldn't easily reproduce this though - when I heard the distortion, I would immediately play the same chord again over and over, but it would not distort. I haven't noticed this at all since switching to the V-Can. So it's possible that the NAD was sometimes running out of reserve capacity or something.

Greg.

 

[Suntory_Times]

Sorry I misread, I read that no matter what it was coming from you're right ear. Something does sound wrong though, the 595 shouldn't distort at listenable volumes at all.

 

[skip129]

I might create a test waveform that represents the kind of stuff I was sending through the headphones to make them distort. My gut feel is that most folks will be able to tolerate a sound level which results in distortion, at least when using the HD595's.

As I say, I don't think it was all that representative of real music, so it's somewhat academic.

Greg.