Rockbox Technical Forums

Rockbox General => Rockbox General Discussion => Topic started by: tvg on August 25, 2006, 01:19:32 AM

Title: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 01:19:32 AM
Rockbox has a poor sound quality. Compared to OF, it has numerous clicks when: stopping, pausing, fading.
1) The click at stop is rather loud to hear it, OF has no click at stop.
2) Every step of volume change has an audible click, though not loud, but it HAS!
3) Fade in - is a total mess of clicks. As I understand, the fade in is realized as gradient volume change. Every step produces one click. So fade in becomes a set of clicks, though fading away.
4) The worst thing is clicks during the playback. I found a place in my silent song where there are audible light clicks. I rewinded and repeated this place again and again. The clicks were the same, but they slightly moved forward (in time). Some time I could repeat it, but after turning on and off I couldn't repeat them on previous place. It seems that the clicks are from HDD, but why are they absent on OF?

I'm telling exclusively about FLAC playing.
Title: Re: Poor sound quality on X5 with RockBox
Post by: LinusN on August 25, 2006, 03:37:53 AM
Wow! I have never heard anything like this on my X5, and you are the first to report it too.
Title: Re: Poor sound quality on X5 with RockBox
Post by: nicolinux on August 25, 2006, 03:46:43 AM
I also never heard something like that... I supposed you listened the same place of your FLAC files with the OF (in case it was a hardware problem) ?
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 04:01:12 AM
Of course the same FLAC, the same place.

Anyway, turn off the "fade in on pause" and listen to clicks on pause keypress - the stop is very inaccurate compared with OF.

Listen to clicks while changing volume: every step causes click (small). OF causes not.

(4) is the most doubtful, but the clicks were reproducible during small rewind and became not reproducible during big rewind. If I started to play the song again, the clicks became reproducible again.
This is difficult problem, I see...

But the clicks on stop, pause and volume change cannot be tolerated! Just listen, listen well - they are not a kind of CLICK, this is ...click...
Title: Re: Poor sound quality on X5 with RockBox
Post by: LinusN on August 25, 2006, 04:28:27 AM
OK, I hear it now. I can only hear it at extreme volume levels.
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 05:45:38 AM
Depends on your hearing ability. And some songs are quiet.
OF does not click at all and pause are accurate. Sad.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Bagder on August 25, 2006, 06:09:01 AM
Quote
the clicks on stop, pause and volume change cannot be tolerated!


I beg to differ. I never heard them. I enjoy my Rockbox on X5.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Taurus on August 25, 2006, 06:18:41 AM

4) The worst thing is clicks during the playback. I found a place in my silent song where there are audible light clicks. I rewinded and repeated this place again and again. The clicks were the same, but they slightly moved forward (in time). Some time I could repeat it, but after turning on and off I couldn't repeat them on previous place. It seems that the clicks are from HDD, but why are they absent on OF?


I'm hearing these clicks too, especially 1 to 3 (4 not so much, as I either haven't noticed it or I don't listen to flac files enough). I'm listening to mp3s mostly and the pause/volume change clicks are there too.

I don't think the clicks you describe in 4 come from hdd, but from playback buffer (as they are not in the same place after restart).
I'm not a developer and haven't looked in the code much, but i guess, especially with large kbit/s flac files, that the audio buffer has problems refilling or isn't filled properly.

But these are just my n00b guesses ;)
Originally I just wanted to report that I'm hearing these clicks too, even with mp3s.

Greets, Taurus
Title: Re: Poor sound quality on X5 with RockBox
Post by: xlarge on August 25, 2006, 06:30:25 AM
I haven't heard any clicks either.
Is this rockbox:x5 with remote?
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 07:00:34 AM

Quote
the clicks on stop, pause and volume change cannot be tolerated!


I beg to differ. I never heard them. I enjoy my Rockbox on X5.


That does not mean that there is no clicks. How can clicks give enjoyment - I don't get.


I'm not a developer and haven't looked in the code much, but i guess, especially with large kbit/s flac files, that the audio buffer has problems refilling or isn't filled properly.


Exactly.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Taurus on August 25, 2006, 07:08:56 AM
I just dived a little more into this.
I gotta say, I don't hear any clicks during playback, even with flacs.
But I DO hear a clicking noise on track change (just when a new track starts, crossfading enabled). (EDIT: and of course on volume change/fade-in etc...)

As for my part, I don't have a remote connected.

The clicks are a little bit better to hear with my Sennheiser CX-300 than with my Sony MDR-EX71SL, as the Sennheisers bring out heights much more than the Sony headphones.

While were on the subject: There is an astonishingly high background noise present with Rockbox!
Just switched back to OF (haven't done this in a looong time :D ) and this noise is not as strong as with Rockbox.
Maybe it's just the different EQ settings that highlight the high frequencies much more, but background noise is definitely stronger in RB than in OF.
But the worst thing for me is that you can even hear HDD noises! Go to full volume (not playing anything, of course ;) ) and e.g. run the disktidy plugin.
You'll hear, clicking, high frequency beeping... all sorts of nasty stuff!

BTW: You can hear volume change click thingy on OF too. Though not while playing a song, but when you paused playback, you'll hear clicking when changing the volume. But that's the only clicking that occured to me in OF.

Do you guys haven't got that AT ALL? Have tvg and I got super-sensitivity ears? Or maybe just defective/bad hardware?
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 07:11:28 AM



Just disable fade in. And try to listen pause clicks.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Llorean on August 25, 2006, 07:13:56 AM
Many times sounds like this won't show up in all earphones. It can depend on the impedence and response of the earphones, so it can be expected that many people won't hears this sort of thing simply because the sounds never get to their ears, not necessarily because they themselves cannot hear the sounds.
Title: Re: Poor sound quality on X5 with RockBox
Post by: xlarge on August 25, 2006, 07:14:39 AM


I beg to differ. I never heard them. I enjoy my Rockbox on X5.


That does not mean that there is no clicks. How can clicks give enjoyment - I don't get.


Your "logic" is reversable; Just because you hear clicks doesn't mean that there are any...
I've never heard any clicks. Not in RB or OF... But then again, i don't crank the volume to 0 either...
And i use etymotic phones.
Title: Re: Poor sound quality on X5 with RockBox
Post by: LinusN on August 25, 2006, 07:15:33 AM
In any case, if the OF is better, we should strive to be equally good.
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 07:16:12 AM



I beg to differ. I never heard them. I enjoy my Rockbox on X5.


That does not mean that there is no clicks. How can clicks give enjoyment - I don't get.


Your "logic" is reversable; Just because you hear clicks doesn't mean that there are any...
I've never heard any clicks. Not in RB or OF... But then again, i don't crank the volume to 0 either...
And i use etymotic phones.


That kind of logic is not reversable. If you don't hear - you just don't listen.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Taurus on August 25, 2006, 07:20:17 AM
Sorry tvg, I don't see what you quoted from me...  ???
But I do hear the pause clicks (and stop clicks when shutting down).

As for the different headphones:
I think you're right, the clicky thing mainly depents on what headphones you're using.
As I mentioned, the noises are stronger on my Sennheisers. That's for example why I don't use them on my Dell office computer, because with the Sennheisers I've got unbearable beeping and humming noises (coming from the low quality onboard soundcard, the HDD & other components I guess), which I don't hear with my Sony headphones.

But still, there are clicks in Rockbox that I can hear even with my Sony MDR-EX71SL.
Title: Re: Poor sound quality on X5 with RockBox
Post by: xlarge on August 25, 2006, 07:25:22 AM

That kind of logic is not reversable. If you don't hear - you just don't listen.


True to some extent; I don't (haven't) crank the volume to max and search for clicks and imperfections.

If you search for it hard enough you will find it, what ever it is.
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 07:28:27 AM
The better headphones you use, the better you hear the clicks. When listening quiet music, the clicks are terrible.

More of that: RockBox shuts down on X5 with terrible Click (and screen garbage), while OF shuts down silently (with blank screen too).


True to some extent; I don't (haven't) crank the volume to max and search for clicks and imperfections.

If you search for it hard enough you will find it, what ever it is.


Just listen to queit music in quiet place. I agree with

In any case, if the OF is better, we should strive to be equally good.


And the sound quality of OF (except gapless) is better, fact.
Title: Re: Poor sound quality on X5 with RockBox
Post by: LinusN on August 25, 2006, 07:29:26 AM
I hear the clicks quite clearly when I crank the volume to the max with my EX-71's. I just haven't heard it before, since it is downright painful to listen to music at that volume level (with those earbuds).
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 07:32:10 AM
I listened Hindemith sonates for flute. Rather quiet record, so I lifted up the volume. It's not painful to lift up. But impossible to listen.
Title: Re: Poor sound quality on X5 with RockBox
Post by: xlarge on August 25, 2006, 07:35:44 AM

The better headphones you use, the better you hear the clicks. When listening quiet music, the clicks are terrible.

More of that: RockBox shuts down on X5 with terrible Click (and screen garbage), while OF shuts down silently (with blank screen too).

Just listen to queit music in quiet place. I agree with ....
And the sound quality of OF (except gapless) is better, fact.


What headphones would you recommend for optimal click-awareness?
I guess, quiet music in a quiet place on quite high volume (since the music is quite quiet?)

Terrible click and Screen garbage on shut down?
It clicks once on shutdown aswell as once turn on - for me.
The OF does that aswell... Clicks that is.
Don't tell me your OF doesn't click on shutdown?

But no screen garbage.
Is your x5 hardware and/or rockbox installation ok?
What versions are you running?
Title: Re: Poor sound quality on X5 with RockBox
Post by: xlarge on August 25, 2006, 07:40:46 AM

...
And the sound quality of OF (except gapless) is better, fact.


What settings do you use in OF to have better sound quality?
And how does that become a fact?
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 07:42:04 AM

What headphones would you recommend for optimal click-awareness?
I guess, quiet music in a quiet place on quite high volume (since the music is quite quiet?)


Discusion with you is counterproductive, so I won't speak with you. Do not bother yourself.


OF clicks only at start and not at shutdown.
Title: Re: Poor sound quality on X5 with RockBox
Post by: madcow on August 25, 2006, 07:43:10 AM
No click at al!

Only in the beginning of the X5 rockbox port.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Taurus on August 25, 2006, 07:44:23 AM

What headphones would you recommend for optimal click-awareness?
I guess, quiet music in a quiet place on quite high volume (since the music is quite quiet?)

Terrible click and Screen garbage on shut down?
It clicks once on shutdown aswell as once turn on - for me.
The OF does that aswell... Clicks that is.
Don't tell me your OF doesn't click on shutdown?

But no screen garbage.
Is your x5 hardware and/or rockbox installation ok?
What versions are you running?


I'm recommending Sennheiser CX-300.
I'm running a bleeding edge build.
Shutdown seems fine to me except for the (single) stop click and potential HDD accesses.

It also depends on EQ settings. I've got rather extreme EQ settings, which seem to highlight the clicks (-24DB Precut and Vol +6).
With EQ off and normal volume, the clicks are barely or not at all hearable, but with loud volumes they're there too.

My EQ (this EQ extremely boost bass):

eq precut: 240

eq band 0 cutoff: 80
eq band 0 q: 10
eq band 0 gain: 240

eq band 1 cutoff: 200
eq band 1 q: 10
eq band 1 gain: -240

eq band 2 cutoff: 800
eq band 2 q: 10
eq band 2 gain: -240

eq band 3 cutoff: 4000
eq band 3 q: 10
eq band 3 gain: -240

eq band 4 cutoff: 12000
eq band 4 q: 7
eq band 4 gain: -240

Volume (for me) with this EQ has to be 0 to +6 outdoors and -12 to -6 indoors.

EDIT: Added Quote
Title: Re: Poor sound quality on X5 with RockBox
Post by: Llorean on August 25, 2006, 07:47:01 AM
Okay, first off, the *only* way to validly compare the two firmwares is with both having their EQ off. For example, since the X5 doesn't have a full parametric EQ, how can you be certain that any clicks brought out in Rockbox by an EQ wouldn't also show up in the OF with the same EQ?

I'm not dismissing the clicks, I'm just saying that they should be investigated flatly.
Title: Re: Poor sound quality on X5 with RockBox
Post by: xlarge on August 25, 2006, 07:54:23 AM
What headphones do you use?
I'm a bit worried; if it really clicks that terribly as you say - why don't i hear them?
And what versions of rockbox do you use?

Answer those questions and we'll be a bit further enlightenment...
If I duplicate your setup i'd hear your clicks too - right? (as long as the clicks aren't higher than ~19khz)
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 25, 2006, 07:59:17 AM

Okay, first off, the *only* way to validly compare the two firmwares is with both having their EQ off. For example, since the X5 doesn't have a full parametric EQ, how can you be certain that any clicks brought out in Rockbox by an EQ wouldn't also show up in the OF with the same EQ?

I'm not dismissing the clicks, I'm just saying that they should be investigated flatly.


I'm telling about comparison with TOTAL absence of any EQ in either RB or OF. No sound enhancments, no EQs are on.
The only way to validly compare, as I understand, is to record to the PC from Line-out and to give you theese graphics.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Llorean on August 25, 2006, 08:00:49 AM
tvg, it's rather clear I was responding to the person who was admitting to using an equalizer.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Taurus on August 25, 2006, 08:08:49 AM

What headphones do you use?
I'm a bit worried; if it really clicks that terribly as you say - why don't i hear them?
And what versions of rockbox do you use?

Answer those questions and we'll be a bit further enlightenment...
If I duplicate your setup i'd hear your clicks too - right? (as long as the clicks aren't higher than ~19khz)


Yeah, try these EQ settings! As I said, I didn't hear the clicks with EQ off either. But I'm sure if I had Vol +6 with EQ off, I'd hear them too. It's just that this is too loud for me ;)

By the way: In OF with EQ, MachBass, etc. OFF I heard clicks on:
- Startup (one click, loud)
- Volume change (while paused or running a track that has a long silence in it ) from ~Vol 30 on upwards. I cannot hear the volume change clicks beneath ~Vol 30.
Maybe there are clicks on track change too. I just couldn't put the volume up that much without permanently going deaf or seriously disturbing the guys in my office ;)
Maybe I'll try it at home with (passive) speakers.

I think the main problem is that Rockbox allows you to 'mess' around with the EQ much more (e.g. more loudness) so you hear more clicks than with OF. But I still think that there are clicks that could be avoided in RB (track change for example?).
What bothers me too is the HDD noise. I didn't hear any HDD noise in OF...
Title: Test
Post by: nicolinux on August 25, 2006, 04:57:05 PM
I just tried here : when I put the volume at the maximum, yes I can hear clicks. But I have to go around -4 to heat something and only around -1/0 to clearly hear them. I didn't try with music because I want to save my ears a little longer.

I used no EQ and I made the test with and without the remote (it's exactly the same).

After that, I tried at "normal" volume (between -40 and -30 for me) and I didn't hear anything at all, even if I listened very very carefully. So, for me, this isn't a problem at all because I'll never listen at those high volumes...

I think the headphones are very important too. I don't really know the technical aspects, but I believe the more impedance there is, the less you should hear those clicks. I use Sennheiser HD555 which have an impedance of 55ohms. It's not that important but it's more than most of the "little" headsets (excuse me, I can't find the exact word in english...).

Speaking about remote, I must say that Rockbox is really better with those little sounds which were present with the OF (mainly when scrolling in the files). As with the Iriver (I had an H120), there isn't any sound... Rockbox is better with this sound aspect...
Title: Re: Test
Post by: tvg on August 26, 2006, 02:01:52 AM

Speaking about remote, I must say that Rockbox is really better with those little sounds which were present with the OF (mainly when scrolling in the files). As with the Iriver (I had an H120), there isn't any sound... Rockbox is better with this sound aspect...


What do you mean "better"? Better to have almost unheard clicks? Or what better? I tell you the conditions at those the clicks are heard well and annoying.
What is your conclusion? What is the point where sound is better in RB than OF on X5? Do you think that it would be better to leave "better" sound as is, enjoying beautiful games and fonts and menus in RB?
Title: Re: Test
Post by: nicolinux on August 26, 2006, 04:00:48 AM


Speaking about remote, I must say that Rockbox is really better with those little sounds which were present with the OF (mainly when scrolling in the files). As with the Iriver (I had an H120), there isn't any sound... Rockbox is better with this sound aspect...


What do you mean "better"? Better to have almost unheard clicks? Or what better? I tell you the conditions at those the clicks are heard well and annoying.
What is your conclusion? What is the point where sound is better in RB than OF on X5? Do you think that it would be better to leave "better" sound as is, enjoying beautiful games and fonts and menus in RB?


I'm not sure I undersand you very well... Yes, it's better because there isn't any clicks. But do you have the remote ? Because it's not the same clicks...

I did other tests and I heard other things. The "clicks" when the volume is at maximum can be heard in the OF too. So I suppose it's more an hardware issue than a software one.

And I did heard some little "clicks" when playing or pausing and when changing track. But I didn't paid any attention to them until now, since they didn't bother me at all and since I hear them only at higher volume as usual.
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 27, 2006, 05:38:41 AM
Can anybody tell me, are these clicks heard on IRiver or iPod? Does this mean iaudio is technically inferior than others?
Title: Re: Poor sound quality on X5 with RockBox
Post by: AlexP on August 27, 2006, 07:44:31 AM
I can't hear them or iriver h140 - I luckily also have a H140 that doesn't tick with the remote, so I don't know if that might be related.
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 27, 2006, 12:25:56 PM
Thank you very much, Llorean and others, who supported me. Thanks to Mike Sevakis (26/08/2006), the problem with inaccurate stop is solved! The stops and starts are accurate and almost as in OF. Light clicks are heard on volume change, but nearly the same as in OF, though RB still has a huge click on shutdown.

What is really annoying me, it is still (4) number from my first message. Light clicks, which are hear while listening to FLACs at normal volume. I cannot figure out how are they created and where from do they go... But they are:
1) Heard at -36 volume (!!!!!!!!!!!!!!!!!!!) in quiet place (Koss Porta Pro)
2) Go in 3-packets: (click-click-click)=1-1.5 sec.
3) Sometimes they are not present.
4) Reproducible from time to time
5) They are some kind of CD clicks, but neither original FLAC or FLAC in OF reproduce these clicks.

I think they are not present in OGG files. Any ideas, please? I beg these clicks ARE present and they are NOT of a hardware cause. On FLACs. 44100, 16 bit, ripped from CD.
Title: Re: Poor sound quality on X5 with RockBox
Post by: bk on August 27, 2006, 01:18:24 PM
I've noticed sporadic clicks/skips with long low-bitrate Ogg files on X5. They occur every 10-30 seconds and are like a 1-2 second audio dropout. The files are around 32kbps mono (22050 Hz), from 3-4 hours long. They don't occur on a PC.

I haven't been able to consistently reproduce the problem, otherwise I would've filed a flyspray report.
Title: Re: Poor sound quality on X5 with RockBox
Post by: Llorean on August 27, 2006, 01:31:50 PM
The Rockbox resampler is less than ideal, so anything not at 44.1kHz may have fairly noticeable artifacts.
Title: Re: Poor sound quality on X5 with RockBox
Post by: jhMikeS on August 27, 2006, 04:48:21 PM

Light clicks are heard on volume change, but nearly the same as in OF, though RB still has a huge click on shutdown.


The big click at shutdown was solved a long time ago my RaeNye by powering down the TLV320 nicely. x5 just has a whoosh like OF. I enabled zero-crossing detection for the volume control which softens it up as much as it will ever get without software intervention.
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 28, 2006, 12:05:24 AM
The big click was solved when RB shutdowns properly, it happens every 1/2 time. Every another 1/2 time it shutdowns inproperly and, of course, there is a huge click. But may be it is another problem and should be noted in separate thread.
MikeS: but the most meaningful problem is sporadic clicks during playback... Is it possible to discover it somehow?
Title: Re: Poor sound quality on X5 with RockBox
Post by: tvg on August 30, 2006, 12:08:38 AM
Nobody cares. unfortunately...
Title: Re: Poor sound quality on X5 with RockBox
Post by: Bagder on August 30, 2006, 01:31:51 AM

Nobody cares. unfortunately...


Yes we do. But you are a troll and do obviously not deserve quality replies.