The original Clip (V1)  with original firmware is 0.7 percent fast.  CLip+ with OF is reported to be about half that, but I haven't measured one myself.

Quote from: DonP on 2010-12-15 22:11:49

The original Clip (V1)  with original firmware is 0.7 percent fast.  CLip+ with OF is reported to be about half that, but I haven't measured one myself.

My Clip+ running about 3 week old Sansa firmware seems to run within 0.01% of perfect speed. IOW, a 999.9 Hz sine wave test signal in a FLAC file comes out of  the headphone jack as a 999.9 Hz sine wave. The audio capture device was my Microtrack which should be within 0.005%.  I made the frequency estimates in CEP 2.1.

Quote from: Squeller on 2010-12-16 14:29:48

In case of classical music, say, orchestral music, I'd apply vlevel.sf.net (available for fb2k for instance) on the audio material to flatten the very high dynamics, which aren't "useful" in a noisy or headphone environment.

You don't need to do that with rockbox. It has a quite decent compressor DSP.

Quote from: Arnold B. Krueger on 2010-12-16 17:17:36

Quote from: DonP on 2010-12-15 22:11:49

The original Clip (V1)  with original firmware is 0.7 percent fast.  CLip+ with OF is reported to be about half that, but I haven't measured one myself.

My Clip+ running about 3 week old Sansa firmware seems to run within 0.01% of perfect speed. IOW, a 999.9 Hz sine wave test signal in a FLAC file comes out of  the headphone jack as a 999.9 Hz sine wave. The audio capture device was my Microtrack which should be within 0.005%.  I made the frequency estimates in CEP 2.1.

This is the first measurement I saw, a few weeks after the clip+ came out:

Quote from: DonP on 2010-12-16 18:23:09

This is the first measurement I saw, a few weeks after the clip+ came out:

Yeah those are out of date.  Plenty of people have tested more recently.  Check google and you can find newer tests.

Quote from: saratoga on 2010-12-16 19:11:10

Quote from: DonP on 2010-12-16 18:23:09

This is the first measurement I saw, a few weeks after the clip+ came out:

Yeah those are out of date.  Plenty of people have tested more recently.  Check google and you can find newer tests.

Any clues what search terms you use or where the newer tests are?  I saw one other measurement on anythingbutipod Jan 20 which was similar.  I found release notes for 3 firmware updates with no mention of fixing pitch.

Were those tests made out of date by a hardware  or firmware change?

If I already set -9db as a threshold, loud mid frequencies such as trumpets start to crackle.

Another problem is, that Rockbox produces kind of digital noise on every track change for 2 seconds, I've tested it with vorbis, mp3 and musepack now.

http://www.anythingbutipod.com/forum/showp...p;postcount=629

Quote from: DonP on 2010-12-16 21:29:44

Were those tests made out of date by a hardware  or firmware change?

Firmware.  They reclocked the DAC, same as we did. 

Quote from: saratoga on 2010-12-16 21:53:12

http://www.anythingbutipod.com/forum/showp...p;postcount=629

Quote from: DonP on 2010-12-16 21:29:44

Were those tests made out of date by a hardware  or firmware change?

Firmware.  They reclocked the DAC, same as we did. 

That post shows pitch with the Sansa firmware still at +0.25%, unchanged.

Quote from: Squeller on 2010-12-16 18:51:22

If I already set -9db as a threshold, loud mid frequencies such as trumpets start to crackle.

Can't reproduce even at 24 dB compression.  Can you post your complete config file?  Its possible its due to a combination of DSP effects.

# .cfg file created by rockbox 3.7.1 - [url=http://www.rockbox.org]http://www.rockbox.org[/url]

volume: -18
balance: 0
bass: 0
treble: 0
channels: stereo
stereo_width: 100
shuffle: off
repeat: off
contrast: 0
backlight timeout: 20
backlight timeout plugged: 30
invert: off
flip display: off
selector type: bar (inverse)
statusbar: top
scrollbar: left
scrollbar width: 6
volume display: graphic
battery display: graphic
time format: 24hour
show icons: on
idle poweroff: 10
max files in playlist: 10000
max files in dir: 1000
battery capacity: 290
car adapter mode: off
force fm mono: off
backlight filters first keypress: off
caption backlight: off
scroll speed: 10
scroll delay: 1000
bidir limit: 50
Screen Scrolls Out Of View: off
scroll step: 6
screen scroll step: 16
scroll paginated: off
play selected: on
party mode: off
volume fade: off
scan min step: 1
seek acceleration: normal
start directory: /
show files: all
sort case: off
sort dirs: alpha
sort files: alpha
sort interpret number: numbers
show filename exts: view_all
follow playlist: off
playlist viewer icons: on
playlist viewer indices: on
playlist viewer track display: track name
recursive directory insert: on
autocreate bookmarks: off
autoupdate bookmarks: off
autoload bookmarks: off
use most-recent-bookmarks: off
peak meter clip hold: 60
peak meter hold: 500ms
peak meter release: 8
peak meter dbfs: on
peak meter min: 60
peak meter max: 0
peak meter clipcounter: off
talk menu: off
talk dir: off
talk dir clip: off
talk file: off
talk file clip: off
talk filetype: off
Announce Battery Level: off
rec timesplit: off
rec sizesplit: off
rec channels: mono
rec mono mode: L+R
rec split type: Split
rec split method: Time
rec source: mic
prerecording time: 3
rec path: /Record/
cliplight: off
rec mic gain: 23
rec left gain: 23
rec right gain: 23
rec frequency: 44
rec format: wvpk
mp3_enc bitrate: 192
trigger start threshold dB: -45
trigger start threshold linear: 5
trigger stop threshold dB: -45
trigger stop threshold linear: 10
trigger start duration: 1s
trigger stop duration: 5s
trigger min gap: 10min
trigger mode: repeat
trigger type: stop
folder navigation: on
gather runtime data: off
replaygain type: track shuffle
replaygain noclip: on
replaygain preamp: 0
beep: weak
crossfade: shuffle or man track skip
crossfade fade in delay: 0
crossfade fade out delay: 0
crossfade fade in duration: 2
crossfade fade out duration: 2
crossfade fade out mode: crossfade
crossfeed: off
crossfeed direct gain: -15
crossfeed cross gain: -60
crossfeed hf attenuation: -160
crossfeed hf cutoff: 700
eq enabled: off
eq precut: 0
eq band 0 cutoff: 60
eq band 1 cutoff: 200
eq band 2 cutoff: 800
eq band 3 cutoff: 4000
eq band 4 cutoff: 12000
eq band 0 q: 7
eq band 1 q: 10
eq band 2 q: 10
eq band 3 q: 10
eq band 4 q: 7
eq band 0 gain: 0
eq band 1 gain: 0
eq band 2 gain: 0
eq band 3 gain: 0
eq band 4 gain: 0
dithering enabled: off
timestretch enabled: off
compressor threshold: -12
compressor makeup gain: off
compressor ratio: 4:1
compressor knee: soft knee
compressor release time: 500
dircache: off
tagcache_ram: off
tagcache_autoupdate: off
default codepage: iso8859-1
warn when erasing dynamic playlist: on
hold_lr_for_scroll_in_list: on
show path in browser: current directory
fm_region: eu
Last.fm Logging: off
fmr: -
fms: /.rockbox/wps/cabbiev2.fms
font: /.rockbox/fonts/08-Namil.fnt
wps: /.rockbox/wps/cabbiev2.wps
sbs: -
lang: /.rockbox/langs/deutsch.lng
kbd: -
cuesheet support: off
skip length: track
start in screen: root
iconset: 
viewers iconset: 
list_accel_start_delay: 2
list_accel_wait: 3
keyclick: off
keyclick repeats: off
playlist catalog directory: /Playlists
qs top: show files
qs left: shuffle
qs right: repeat
qs bottom: show files
prevent track skip: off
Semitone pitch change: off
Timestretch mode: off
ui viewport: -
resume rewind: 5

Quote from: Squeller on 2010-12-16 18:51:22

Another problem is, that Rockbox produces kind of digital noise on every track change for 2 seconds, I've tested it with vorbis, mp3 and musepack now.

I've never heard of this.  If  you can suggest someway to reproduce it, I'll look into it.

Wow sorry, I guess I'm completely wrong.  I was sure I read that Sandisk fixed it, but I guess not.

Its probably more cost effective to just buy another clip.  I think I paid $20 for my 4GB one.  They're basically disposable.