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SanDisk Professor
Posts: 579
Registered: ‎12-02-2008

Re: Pitch bug on Clip+?

[ Edited ]

@schnarky42 wrote:

 

1000hz

Dell D630c (laptop) - plays 1000.02hz

Sansa E200           - plays 1000.39hz

Rio Karma             - plays 1000.48hz

Sansa Clip+           - plays 1002.47hz

 

That gives Sansa clip a pitch error of 0.247%, compared to the next player (Rio Karma) at 0.048%.

----------------------------------------

 


 
It looks like it did get improved over the original V1 clip.  I measured a 1000 Hz tone as playing back at 1007 Hz, so +0.7%.  Some others measured the same percent error by various means.   
All the players I had available were consistent with your findings... battery powered ones on the order of 10x closer than (original) clip, and AC powered ones (CD and DVD players) another leap closer yet.

 

Message Edited by donp on 09-04-2009 10:35 AM
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SanDisk User
Posts: 30
Registered: ‎04-11-2008

Re: Pitch bug on Clip+?

any idea of the results for the original clip?  I'ld also be curious to see what the results for the ipod would be.
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Newbie
Posts: 12
Registered: ‎09-04-2009

Re: Pitch bug on Clip+?


@tipsypenguin wrote:
any idea of the results for the original clip?  I'ld also be curious to see what the results for the ipod would be.

donp's results are from the v1 clip. User daytona955 also did some tests on the fuze v1 here. Both have the pitch bug. Any ipod would need to be tested in a similar way to what others and I have done.

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Newbie
Posts: 8
Registered: ‎09-03-2009

Re: Pitch bug on Clip+?

It's quite sad that the Clip excels at so many things, except playing the actual music.

 

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SanDisk User
Posts: 63
Registered: ‎02-02-2009

Re: Pitch bug on Clip+?

Well Sansa?  When are you going to answer this thread finally?

 

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SanDisk Guru
Posts: 4,898
Registered: ‎11-17-2008

Re: Pitch bug on Clip+?


@schnarky42 wrote:

@tipsypenguin wrote:
any idea of the results for the original clip?  I'ld also be curious to see what the results for the ipod would be.

donp's results are from the v1 clip. User daytona955 also did some tests on the fuze v1 here. Both have the pitch bug. Any ipod would need to be tested in a similar way to what others and I have done.


In the interest of accuracy...yes, the Fuze did have it, but it was fixed with a firmware update....so Sansa does know how to fix it.

iPod Touch 5G 32GB, Touch 4G 32GB, Clip Sport 8GB.
Rockbox-> Clip Zip 4GB, iPod Nano 2G 4GB, iPod 5.5G 80GB
2012 Nexus 7 32GB, Asus MeMoPad 8 16+64GB, LG Optimus G Pro, Nokia Lumia 900, Nokia Lumia 520

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SanDisk Professor
Posts: 579
Registered: ‎12-02-2008

Re: Pitch bug on Clip+?

[ Edited ]

@wavydavy wrote:

Thanks for doing the tests Donp.

I assume you used Mp3 encoded at 44.1 sample rate.

I wonder what the error is for Mp3 at 48 kHz sample rate?

Other sample rates?

Other file types... flac.  ogg. wav.?

If you can hear a beat frequency (the sound of two tones out of tune with each other) when playing 1000 Hz and 1002.47 Hz tones at the same time, then the Clip + is likely to sound off pitch when played with an instrument.

I'm not sure yet if this is close enough for my purposes.

I wonder if they tried to fix it with firmware or if they changed the clock freq of the Xtal?

Amazing that Sansa can't do better in this area that everyone else seems to get right.

 

This flies in the face of the claims of superior audio playback quality.

One of the Clips purported strong selling points is actually not true!

 

 

 

There's a thread under Fuze about this problem http://forums.sandisk.com/sansa/board/message?board.id=sansafuse&thread.id=11835&view=by_date_ascend...  talk of Sansa's fix is around page 14.

 

As long as the sample frequency was 44 khz it didn't matter whether the format was ogg, flac, or mp3. 

 

I recall that it was a lot better for 48 kHz so after a round of denial and "it doesn't matter" posts, a bunch were saying to just reencode your whole collection to 48 kHz. :smileyvery-happy:  I don't know that anyone tested lower sample rates.

 

The clock frequency affecting pitch isn't the frequency of the crystal itself, but one derived from it using a phase locked loop.  On the fuze, Sansa was able to choose a different PLL frequency with just a firmware change. 

 

To be fair to those who rave about the clip's sound, the usual quantitative measures are things like frequency response, S/N ratio, and distortion, maybe time delay/stability between channels. Qualitiative might include soundstaging.  It probably didn't occor to anyone to check the pitch (because, after all, "nobody" gets that wrong once you're past mechanical playback devices). 

 

 

 

Message Edited by donp on 09-04-2009 03:32 PM
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Newbie
Posts: 12
Registered: ‎09-04-2009

Re: Pitch bug on Clip+?

donp,

 

sansafix's comment in that thread (message here) shows the improvement, but I didn't think they implemented it in any fuze firmware.

 

Later in that same thread, mp3geek references from Wikipedia one study that showed the just disconcernable difference threshold of human hearing to be around 0.3% pitch error. This would suggest that for the majority of people, the clip+, at 0.247% pitch error, will qualitatively go unnoticed as having a pitch error. On the flip side, from an instrument tuning perspective, .247% pitch error is not acceptable, and gtune's vst plugin shows that the 1000hz tone on the clip+ is 'out of tune'.

 

 

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SanDisk User
Posts: 28
Registered: ‎03-08-2008

Re: Pitch bug on Clip+?

Thanks for posting that link.

It has a lot of useful info about this problem and shows that a lot of other people are concerned about it.

It's a shame Sandisk won't  respond to requests for info about a fix for the Clip.

 

I'm now sorry I recommended the Clip to my friends before I discovered this problem.

I've now had to admit I was mistaken and advise them to avoid Sansa Products until Sansa get their act together.

It's clear now that the Clip could never be sold in a music store with it's playback speed/pitch problem.

It's to bad, otherwise it would be a great musicians buddy.

 

Yes, it was an oversight to assume that the playback speed/pitch would be accurate, based on the fact that all other contemporary products are and no company in their right mind would release a digital audio product that wasn't.

Having said that.

Playback speed accuracy is a serious sound quality metric to me.

And so I stand by my statement that until the speed/pitch problem is fixed, the Clip and possibly the Clip + cannot be said to have excellent sound quality.

 

Come on Sansa software dev team, has Sansa management cut off your ?

Your customers are on this forum begging for info!

Where is your voice?

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Newbie
Posts: 4
Registered: ‎08-31-2009

Re: Pitch bug on Clip+?

Hmmm... as the originator of this thread, I'm interested to see that there are reports of there being pitch bugs with the v1 Clip.

 

I have 2 v1 Clips -- a 2GB and a 4GB and don't hear problems with them (and hear no differences when running Rockbox on either of them). It was an 8GB v2 Clip that played back audibly too slowly to my ears.