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diff --git a/e200man/manual/configure_rockbox/sound_settings.tex b/e200man/manual/configure_rockbox/sound_settings.tex deleted file mode 100644 index 6ec49a057d..0000000000 --- a/e200man/manual/configure_rockbox/sound_settings.tex +++ /dev/null @@ -1,626 +0,0 @@ -% $Id$ % -\screenshot{configure_rockbox/images/ss-sound-settings}{The sound settings screen}{} - -The sound settings menu offers a selection of sound settings you may -change to customise your listening experience. - -\section{\label{ref:volume}Volume} - This setting adjusts the volume of your music. Like most professional - audio gear and many consumer audio products, Rockbox uses a decibel scale - where 0~dB is a reference that indicates the maximum volume that the \dap{} - can produce without possible distortion (clipping). All values lower than - this reference will be negative and yield a progressively softer volume. - \nopt{iriverh100,iriverh300,ondavx777}{% - Values higher than 0~dB are available and can be used to raise the - volume more than would otherwise be possible. These volume levels will - ordinarily lead to distorted sound, but might work nicely for music that has - an otherwise low volume level. - } - The volume can be adjusted from a - \opt{player}{minimum of -78~dB to a maximum of +18~dB.}% - \opt{recorder,recorderv2fm,ondio}{minimum of -100~dB to a maximum of +12~dB.}% - \opt{iriverh100,iriverh300}{minimum of -84~dB to a maximum of 0~dB.}% - \opt{iaudiom3,iaudiom5,iaudiox5,ipod3g,ipod4g,gigabeatf,mrobe100,mpiohd200}{% - minimum of -73~dB to a maximum of +6~dB.}% - \opt{ipodnano}{minimum of -72~dB to a maximum of +6~dB.}% - \opt{ipodvideo,cowond2}{minimum of -89~dB to a maximum of +6~dB.}% - \opt{ipodnano2g,ipodcolor,ipod1g2g,iriverh10,iriverh10_5gb,sansa,sansaAMS}{minimum of - -74~dB to a maximum of +6~dB.}% - \opt{gigabeats}{minimum of -90~dB to a maximum of +6~dB.}% - \opt{gigabeatf,vibe500}{minimum of -74~dB to a maximum of +6~dB.}% - \opt{fuzeplus}{minimum of -100~dB to a maximum of +6~dB.} - \opt{ipodvideo}{\\Remark: Lowering the volume below -57~dB will also affect the line-out - and the recording gain.} - \opt{cowond2}{\\Remark: Lowering the volume below -57~dB will also affect the line-out.} - -\nopt{gigabeats}{ -\section{Bass} - This setting emphasises - \nopt{iriverh100,iriverh300}{or suppresses} - the lower (bass) frequencies in the sound. A value of 0~dB means that bass - sounds are unaltered (flat response). - \opt{masd}{The minimum setting is -15~dB and the maximum is 15~dB.}% - \opt{masf}{The minimum setting is -12~dB and the maximum is 12~dB.}% - \opt{iriverh100,iriverh300}{The minimum setting is 0~dB and the maximum is 24~dB.}% - \opt{ipodnano,ipodnano2g,ipodcolor,mpiohd200}{% - The minimum setting is -6~dB and the maximum is 9~dB.}% - \opt{ipodvideo}{The minimum setting is -12~dB and the maximum is 12~dB.}% - \opt{iaudiom3,iaudiom5,iaudiox5,sansa,sansaAMS,iriverh10,iriverh10_5gb,vibe500,fuzeplus}{% - The minimum setting is -24~dB and the maximum is 24~dB.} - -\section{\label{ref:volume_limit}Volume Limit} - This setting adjusts the maximum volume of your music. The setting is by - default set to the maximum volume which equals to no limit. To set a volume - limit, select a volume from the list and the maximum volume will be limited to - the selected value all over the system. - -\opt{ipodvideo}{ -\section{Bass Cutoff} - This setting controls the frequency below which the bass adjustment applies. - The setting has a range from 1 to 4, where a bigger number affects a bigger - range of bass frequencies. The actual cutoff frequency used for each setting - value will vary with sample rate. -} - -\section{Treble} - This setting emphasises - \nopt{iriverh100,iriverh300}{or suppresses} - the higher (treble) frequencies in the sound. A value of 0~dB means that - treble sounds are unaltered (flat response). - \opt{masd}{The minimum setting is -15~dB and the maximum is 15~dB.}% - \opt{masf}{The minimum setting is -12~dB and the maximum is 12~dB.}% - \opt{iriverh100,iriverh300}{The minimum setting is 0~dB and the maximum is 6~dB.}% - \opt{ipodnano,ipodnano2g,ipodcolor,mpiohd200}{% - The minimum setting is -6~dB and the maximum is 9~dB.}% - \opt{ipodvideo}{The minimum setting is -12~dB and the maximum is 12~dB.}% - \opt{iaudiom3,iaudiom5,iaudiox5,sansa,sansaAMS,iriverh10,iriverh10_5gb,vibe500,fuzeplus}{% - The minimum setting is -24~dB and the maximum is 24~dB.} - -\opt{ipodvideo}{ -\section{Treble Cutoff} - This setting controls the frequency above which the treble adjustment applies. - The setting has a range from 1 to 4, where a bigger number affects a smaller - range of treble frequencies. The actual cutoff frequency used for each setting - value will vary with sample rate. -} -} - -\opt{gigabeats}{ -\section{Tone Controls} - There is a five-band equalizer built into your \dap{} that allows you to - control various different parameters for each band. This equalizer is - implemented in hardware, and therefore does not tax the processor when in use. - Rockbox also features a more advanced five-band equalizer (see - \reference{ref:EQ}) that is implemented in software and allows more fine - grained control, but also requires more processor time. - - \begin{description} - \item[Band 1 Gain.] - This band acts as a low shelf filter that boosts or lowers all - frequencies below a certain frequency limit, much as a ``bass'' - control found on ordinary stereo systems does. The ``gain'' parameter - controls how much the loudness of the band is adjusted. Positive - numbers make the EQ band louder, while negative numbers make that EQ - band quieter. - \item[Bands 2-4 Gain.] - These bands act as peaking filters that boost or lower a frequency - range centered at a certain frequency. Graphic equalizers in home - stereos are usually peaking filters. The ``gain'' parameter controls - how much each band is adjusted as with the the low shelf filter. - \item[Band 5 Gain.] - Band 5 acts as a high shelf filter, boosting or lowering all - frequencies above a certain frequency limit, much like a ``treble'' - control found on ordinary stereo systems does. As with the other bands, - ``gain'' controls how much each band is adjusted. - \item[Advanced Tone Control Settings.] - This submenu allows you to change advanced parameters for each band. - \end{description} - - As a general guide, EQ band 1 should be used for low frequencies, EQ bands 2 - to 4 should be used for mids, and EQ band 5 should be used for highs.\\* - - \subsection{Advanced Tone Control Settings} - As in the previous menu, the ``gain'' setting controls how much the - loudness of the band is adjusted. In addition the following parameters - can be adjusted: - - \begin{description} - \item[Band 1 Frequency.] - The ``frequency'' parameter sets where the shelving starts to take - effect. For example, a cutoff frequency of 80~Hz will adjust only very - low frequencies. A cutoff frequency of 175~Hz, on the other hand, will - adjust a much wider range of bass frequencies. - \item[Bands 2-4 Frequency.] - The ``frequency'' parameter for these bands sets the centre frequency of - the range that is affected by the gain set. - \item[Bands 2-4 Width.] - This parameter sets the width of the range around the centre frequency - that is affected by the tone control. The possible settings are - ``wide'' or ``narrow''. - \item[Band 5 Frequency.] - This works just as for band 1 frequency, except that it affects the - high frequency end of the spectrum instead of the low. - \end{description} - -} - -\section{Balance} - This setting controls the balance between the left and right channels. The - default, 0, means that the left and right outputs are equal in volume. - Negative numbers increase the volume of the left channel relative to the - right, positive numbers increase the volume of the right channel relative - to the left. - -\section{Channels} - A stereo audio signal consists of two channels, left and right. The - \setting{Channels} setting determines if these channels are to be combined in - any way, and if so, in what manner they will be combined. - Available options are: - % - \begin{description} - \item[Stereo.] - Leave the audio signal unmodified. - \item[Mono.] - Combine both channels and send the resulting signal to both stereo - channels, resulting in a monophonic output. - \item[Custom.] - Allows you to manually specify a stereo width with the - \setting{Stereo Width} setting described later in this chapter. - \item[Mono Left.] - Plays the left channel in both stereo channels. - \item[Mono Right.] - Plays the right channel in both stereo channels. - \item[Karaoke.] - Removes all sound that is common to both channels. Since most - music is recorded with vocals being equally present in both channels - to make the singer sound centrally placed, this often (but not - always) has the effect of removing the voice track from a song. This - setting also very often has other undesirable effects on the sound. - \end{description} - -\section{Stereo Width} - Stereo width allows you to manually specify the effect that is applied - when the \setting{Channels} setting is set to ``custom''. - All values below 100\% will progressively mix the contents of one channel - into the other. This has the effect of gradually centering the stereo image, - until you have monophonic sound at 0\%. Values above 100\% will progressively - remove components in one channel that is also present in the other. This has - the effect of widening the stereo field. A value of 100\% will leave the - stereo field unaltered. - -\opt{masf}{ - \section{Loudness} - When listening at low volumes, the ear will tend to make bass and treble - frequencies sound quieter than they really are. To compensate for this, - \setting{Loudness} is an effect which emphasises bass and treble in a fashion - suited to the human ear. Frequencies in the vocal range are unaffected, since - the human ear picks these up very easily at any sound level. - It is of course also possible to use this effect at higher volumes for - enhanced bass and treble. -} - -\opt{masf}{ -\section{Auto Volume} - Auto volume is a feature that automatically lowers the volume on loud parts, - and then slowly restores the volume to the previous level over a time - interval. This setting allows this time interval to be configured. Short - values like 20~ms are useful for ensuring a constant volume for in-car use and - other applications where background noise makes a constant loudness desirable. - A longer timeout means that the change in volume back to the previous level - will be smoother, so there will be fewer sharp changes in volume level. -} - -\opt{masf}{ -\section{Super Bass} - This setting changes the threshold at which bass frequencies are affected by - the \setting{Loudness} setting, making the sound of drums and bass guitar - louder in comparison to the rest of the sound. This setting only has an - effect if \setting{Loudness} is set to a value larger than 0~dB. -} - -\opt{masf}{ -\section{MDB {}-- Micronas Dynamic Bass} - The rest of the parameters in this menu relate to the Micronas Dynamic - Bass (MDB) function. MDB is designed to enable the user to hear bass - notes that the headphones and/or speakers are not capable of reproducing. - Every tone has a fundamental frequency (the ``main tone'') and also several - harmonics, which are related to that tone. The human brain has a mechanism - whereby it can actually infer the presence of bass notes from the higher - harmonics that they would generate. - - The practical upshot of this is that MDB produces a more authentic sounding - bass by tricking the brain into believing it is hearing tones that the - headphones or speakers are not capable of reproducing. - - The MDB parameters are as follows: - % - \begin{description} - \item[MDB enable.] - This turns the MDB feature on or off. For many users this will be the - only setting they need, since Rockbox picks sensible defaults for the - other parameters. MDB is turned off by default. - \item[MDB strength.] - How loud the harmonics generated by MDB will be. - \item[MDB Harmonics.] - The percentage of the low notes that is converted into harmonics. - If low notes are causing speaker distortion, this can be set to 100\% - to eliminate the fundamental completely and only produce harmonics in the - signal. If set to 0\% this is the same as turning the MDB feature off. - \item[MDB Centre Frequency.] - The cutoff frequency of your headphones or speakers. This is usually - given in the specification for the headphones/speakers. - \item[MDB shape.] - It is recommended that this parameter be set to 1.5 times the centre frequency. - - This is the frequency up to which harmonics are generated. Some of the - lower fundamentals near the cut{}-off range will have their lower - harmonics cut, since they will be below the range of the speakers. - Fundamentals between the cut{}-off frequency and the lower frequency - will have their harmonics proportionally boosted to compensate and restore - the `loudness' of these notes. - - For most users, the defaults should provide an improvement in sound - quality and can be safely left as they are. For reference, the defaults - Rockbox uses are: - % - \begin{table}[h!] - \begin{rbtabular}{0.5\textwidth}{Xc}{Setting & Value}{}{} - MDB Strength & 50~dB \\ - MDB Harmonics & 48\% \\ - MDB Centre Frequency & 60~Hz \\ - MDB Shape & 90~Hz \\ - \end{rbtabular} - \end{table} - - \end{description} -} - -\opt{swcodec}{ -\section{Crossfeed} - Crossfeed attempts to make the experience of listening to music on - headphones more similar to listening to music with stereo speakers. When you - listen to music through speakers, each ear will hear sound originating from - both speakers. However, the sound from the left speaker reaches your right - ear slightly later than it does your left ear, and vice versa.\\ - - The human ear and brain together are very good at interpreting the time - differences between direct sounds and reflected sounds and using that - information to identify the direction that the sound is coming from. On the - other hand, when listening to headphones, each ear hears only the stereo - channel corresponding to it. The left ear hears only the left channel and - the right ear hears only the right channel. The result is that sound from - headphones does not provide the same spatial cues to your ear and brain as - speakers, and might for that reason sound unnatural to some listeners.\\ - - The crossfeed function uses an algorithm to feed a delayed and filtered - portion of the signal from the right channel into the left channel and vice - versa in order to simulate the spatial cues that the ear and brain receive - when listening to a set of loudspeakers placed in front of the listener. The - result is a more natural stereo image that can be especially appreciated in - older rock and jazz records, where one instrument is often hard-panned to - just one of the speakers. Many people will find such records tiring to listen - to using earphones and no crossfeed effect.\\ - - Crossfeed has the following settings: - \begin{description} - \item[Crossfeed.] - Selects whether the crossfeed effect is to be enabled or not. - \item[Direct Gain.] - How much the level of the audio that travels the direct path from a speaker - to the corresponding ear is supposed to be decreased. - \item[Cross Gain.] - How much the level of the audio that travels the cross path from a speaker - to the opposite ear is to be decreased. - \item[High-Frequency Attenuation.] - How much the upper frequencies of the cross path audio will be dampened. - Note that the total level of the higher frequencies will be a combination - of both this setting and the \setting{Cross Gain} setting. - \item[High-Frequency Cutoff.] - Decides at which frequency the cross path audio will start to be cut - by the amount described by the \setting{High-Frequency Attenuation} - setting. - \end{description} - - Most users will find the default settings to yield satisfactory results, but - for the more adventurous user the settings can be fine-tuned to provide a - virtual speaker placement suited to ones preference. - % TODO: adapt the guidelines for crossfeed settings found here? - % http://www.ohl.to/interests-in-audio/crossfeed-and-eq-for-headphones/ - Beware that the crossfeed function is capable of making the audio distort - if you choose settings which result in a too high output level. -} - -\opt{swcodec}{ -\section{\label{ref:EQ}Equalizer} - \screenshot{configure_rockbox/images/ss-equalizer}{The graphical equalizer}{} - Rockbox features a parametric equalizer (EQ). As the name suggests, a - parametric EQ lets you control several different parameters for each - band of the EQ. \nopt{gigabeats}{In some ways the EQ is similar to the - \setting{Bass} and \setting{Treble} settings described earlier, but the EQ - allows you to control the sound much more carefully. Note that the parameteric - EQ bands will be applied in addition to any bass or treble tone controls. - } \opt{gigabeats}{The EQ is similar to the \setting{Tone Controls} described - above, but allows more delicate control.}\\ - - \note{A maximum of 10 EQ bands are possible on most devices, but using more - than are required will waste battery and introduce additional rounding - noise. For best results, use the fewest number of bands required.} - - Rockbox's parametric EQ is composed of five different bands: - \begin{description} - \item[Band 0: Low shelf filter.] - The low shelf filter boosts or lowers all frequencies below a certain - frequency limit, much as the ``bass'' control found on ordinary - stereo systems does. - Adjust the ``cutoff'' frequency parameter to decide where the shelving - starts to take effect. For example, a cutoff frequency of 50~Hz will - adjust only very low frequencies. A cutoff frequency of 200~Hz, on the - other hand, will adjust a much wider range of bass frequencies. - The ``gain'' parameter controls how much the loudness of the band is - adjusted. Positive numbers make the EQ band louder, while negative - numbers make that EQ band quieter. - The ``Q'' parameter should always be set to 0.7 for the shelving - filters. Higher values will add a small boost around the cutoff - frequency that is almost always undesirable. - \item[Bands 1-8: Peaking filters.] - Peaking EQ filters boost or lower a frequency range centered at the - centre frequency chosen. - Graphic equalizers in home stereos are usually peaking - filters. The peaking filters in Rockbox's EQ lets you adjust three - different parameters for EQ bands 1 through 8. The ``centre'' parameter - controls the centre frequency of the frequency range that is affected - as described above. - The ``gain'' parameter controls how much each band is adjusted, and - works as for the low shelf filter. - Finally, the ``Q'' parameter controls how wide or narrow the affected - frequency range is. Higher Q values will affect a narrower band of - frequencies, while lower Q values will affect a wider band of - frequencies. - \item[Band 9: High shelf filter.] - A high shelf filter boosts or lowers all frequencies above a certain - frequency limit, much as the ``treble'' control found on ordinary - stereo systems does. - The high shelf filter is adjusted the same way as the low shelf filter, - except that it works on the high end of the frequency spectrum rather - than the low end. - \end{description} - As a general guide, EQ band 0 should be used for low frequencies, EQ bands 1 - through 8 should be used for mids, and EQ band 9 should be used for highs. - -\begin {description} - \item[Enable EQ.] - This option controls whether the EQ is on or off. - - \item[Graphical EQ.] - This option brings up a graphic EQ screen, which allows adjustment of each of - the three parameters described above (gain, centre frequency, and Q) for each - of the five EQ bands. - - \begin{btnmap} - \opt{IRIVER_H100_PAD,IRIVER_H300_PAD,IAUDIO_X5_PAD,GIGABEAT_PAD% - ,GIGABEAT_S_PAD,SANSA_C200_PAD,IAUDIO_M3_PAD,MROBE100_PAD% - ,SANSA_CLIP_PAD,SANSA_FUZEPLUS_PAD}{\ButtonRight} - \opt{SANSA_E200_PAD,SANSA_FUZE_PAD,IPOD_4G_PAD,IPOD_3G_PAD}{\ButtonScrollFwd} - \opt{IRIVER_H10_PAD}{\ButtonScrollUp} - \opt{PBELL_VIBE500_PAD}{\ButtonUp} - \opt{MPIO_HD200_PAD}{\ButtonVolUp} - \opt{MPIO_HD300_PAD}{\ButtonScrollUp} - \opt{touchscreen}{\TouchMidRight} - & - \opt{HAVEREMOTEKEYMAP}{ - \opt{GIGABEAT_RC_PAD}{\ButtonRCFF} - \opt{IAUDIO_RC_PAD}{\ButtonRCRight} - &} - Raises the highlighted parameter. - \\ - % - \opt{IRIVER_H100_PAD,IRIVER_H300_PAD,IAUDIO_X5_PAD,GIGABEAT_PAD% - ,GIGABEAT_S_PAD,SANSA_C200_PAD,IAUDIO_M3_PAD,MROBE100_PAD% - ,SANSA_CLIP_PAD,SANSA_FUZEPLUS_PAD}{\ButtonLeft} - \opt{SANSA_E200_PAD,SANSA_FUZE_PAD,IPOD_4G_PAD,IPOD_3G_PAD}{\ButtonScrollBack} - \opt{IRIVER_H10_PAD}{\ButtonScrollDown} - \opt{PBELL_VIBE500_PAD}{\ButtonDown} - \opt{MPIO_HD200_PAD}{\ButtonVolDown} - \opt{MPIO_HD300_PAD}{\ButtonScrollDown} - \opt{touchscreen}{\TouchMidLeft} - & - \opt{HAVEREMOTEKEYMAP}{ - \opt{GIGABEAT_RC_PAD}{\ButtonRCRew} - \opt{IAUDIO_RC_PAD}{\ButtonRCLeft} - &} - Lowers the highlighted parameter. - \\ - % - \opt{IPOD_4G_PAD,IPOD_3G_PAD,PBELL_VIBE500_PAD}{\ButtonLeft} - \opt{IRIVER_H100_PAD,IRIVER_H300_PAD,IAUDIO_X5_PAD,SANSA_E200_PAD,SANSA_C200_PAD% - ,SANSA_FUZE_PAD,GIGABEAT_PAD,GIGABEAT_S_PAD,IAUDIO_M3_PAD,MROBE100_PAD% - ,SANSA_CLIP_PAD,SANSA_FUZEPLUS_PAD}{\ButtonUp} - \opt{IRIVER_H10_PAD,MPIO_HD200_PAD,MPIO_HD300_PAD}{\ButtonRew} - \opt{touchscreen}{\ActionStdPrev} - & - \opt{HAVEREMOTEKEYMAP}{ - \opt{IRIVER_RC_H100_PAD}{\ButtonRCRew} - \opt{GIGABEAT_RC_PAD}{\ButtonRCVolUp} - \opt{IAUDIO_RC_PAD}{\ButtonRCUp} - &} - Moves to the previous EQ band. - \\ - % - \opt{IPOD_4G_PAD,IPOD_3G_PAD,PBELL_VIBE500_PAD}{\ButtonRight} - \opt{IRIVER_H100_PAD,IRIVER_H300_PAD,IAUDIO_X5_PAD,SANSA_E200_PAD,SANSA_C200_PAD% - ,SANSA_FUZE_PAD,GIGABEAT_PAD,GIGABEAT_S_PAD,IAUDIO_M3_PAD,MROBE100_PAD% - ,SANSA_CLIP_PAD,SANSA_FUZEPLUS_PAD}{\ButtonDown} - \opt{IRIVER_H10_PAD,MPIO_HD200_PAD,MPIO_HD300_PAD}{\ButtonFF} - \opt{touchscreen}{\ActionStdNext} - & - \opt{HAVEREMOTEKEYMAP}{ - \opt{IRIVER_RC_H100_PAD}{\ButtonRCFF} - \opt{GIGABEAT_RC_PAD}{\ButtonRCVolDown} - \opt{IAUDIO_RC_PAD}{\ButtonRCDown} - &} - Moves to the next EQ band. - \\ - % - \opt{IRIVER_H100_PAD,IRIVER_H300_PAD,GIGABEAT_PAD,GIGABEAT_S_PAD,IAUDIO_X5_PAD% - ,SANSA_C200_PAD,IPOD_4G_PAD,IPOD_3G_PAD,IPOD_VIDEO_PAD,SANSA_E200_PAD% - ,SANSA_FUZE_PAD,MROBE100_PAD,SANSA_CLIP_PAD,SANSA_FUZEPLUS_PAD}{\ButtonSelect} - \opt{MPIO_HD200_PAD}{\ButtonFunc} - \opt{MPIO_HD300_PAD}{\ButtonEnter} - \opt{PBELL_VIBE500_PAD}{\ButtonOK} - \opt{IRIVER_H10_PAD}{\ButtonRight} - \opt{IAUDIO_M3_PAD}{\ButtonPlay} - \opt{touchscreen}{\TouchCenter - \opt{COWON_D2_PAD}{/ \ButtonMenu}} - & - \opt{HAVEREMOTEKEYMAP}{ - \opt{IRIVER_RC_H100_PAD}{\ButtonRCSelect} - \opt{GIGABEAT_RC_PAD,IAUDIO_RC_PAD}{\ButtonRCPlay} - &} - Toggles the cursor among the three parameters (gain, centre frequency, - Q) for the selected EQ band - \\ - % - \opt{IRIVER_H100_PAD,IRIVER_H300_PAD}{\ButtonMode} - \opt{IPOD_4G_PAD,IPOD_3G_PAD,MPIO_HD300_PAD}{\ButtonMenu} - \opt{IAUDIO_X5_PAD}{\ButtonPower/\ButtonRec} - \opt{IAUDIO_M3_PAD,MPIO_HD200_PAD}{\ButtonRec} - \opt{SANSA_E200_PAD,SANSA_FUZE_PAD,IRIVER_H10_PAD}{\ButtonLeft} - \opt{GIGABEAT_PAD,GIGABEAT_S_PAD,SANSA_C200_PAD,MROBE100_PAD,SANSA_CLIP_PAD}{\ButtonPower} - \opt{PBELL_VIBE500_PAD}{\ButtonCancel} - \opt{SANSA_FUZEPLUS_PAD}{\ButtonBack} - \opt{touchscreen}{\TouchTopLeft - \opt{COWON_D2_PAD}{/ \ButtonPower}} - & - \opt{HAVEREMOTEKEYMAP}{ - \opt{IRIVER_RC_H100_PAD}{\ButtonRCStop} - \opt{GIGABEAT_RC_PAD}{\ButtonRCDsp} - \opt{IAUDIO_RC_PAD}{\ButtonRCRec} - &} - Exits the graphic EQ screen. - \\ - \end{btnmap} - - \item[Pre-cut.] - If too much positive gain is added through the graphical EQ, your music may - distort. The \setting{Precut} setting allows you to apply a global negative - gain to decoded audio, cancelling out positive gain from the EQ. This will - prevent distortion when boosting certain frequency ranges, at the expense of - making audio quieter. - - Alternatively, precut can be used with a flat EQ curve to implement a volume - cap. For example, on a player that allows overdriving the headphone output - to +6dB, maximum volume can be capped to +0dB by applying 6dB of precut. Note - that precut is not applied if EQ is disabled. - -\item[Simple EQ.] -This option provides an easier alternative for those who are daunted by all of -the parameters that can be adjusted using the graphical EQ. With the -\setting{Simple EQ}, the only parameter that can be adjusted is the gain. - -\item[Advanced EQ.] -This sub menu provides options for adjusting the same parameters as the -\setting{Graphical EQ}. The only difference is that the parameters are -adjusted through textual menus rather than through a graphic interface. - -\item[Save EQ Preset.] -This option saves the current EQ configuration in a \fname{.cfg} file. - -\item[Browse EQ Presets.] -This menu displays a list of EQ presets, as well as any EQ configurations saved -using the \setting{Save EQ Preset} option. Users unfamiliar with the -operation of a parametric EQ may wish to use the presets instead of trying to -configure the EQ, or use the presets for designing their own custom EQ -settings. - -\end{description} -} - -\opt{swcodec}{ -\section{Dithering} -This setting controls the dithering and noise shaping functionality of Rockbox. - -Most of Rockbox' audio file decoders work at a higher bit depth than the 16 bits -used for output on the \daps{} audio connectors. The simplest way to -convert from one bit depth to another is simply discarding all the surplus bits. -This is the default behaviour, and adds distortion to the signal that will -vary in character along with the desired sound. - -Dithering adds low-level noise to the signal prior to throwing away the surplus -bits, which gives the resulting signal a uniform noise floor which is -independent of the signal. Most people find this noise preferable to the -time-varying noise heard when not performing dithering. - -After dithering, noise shaping is performed. This basically just pushes the -dithering noise to the parts of the frequency spectrum humans cannot hear so -easily. In Rockbox' case, some of the noise is pushed up to above 10~kHz. - -This setting will be put to its best use when listening to dynamic music with -frequently occuring quiet parts, classical music being a typical example. It is -worth noting that the effects of dithering and noise shaping are very subtle, -and not easily noticable. - -Rockbox uses highpass triangular distribution noise as the dithering noise -source, and a third order noise shaper. -} - -\opt{swcodec}{% -\opt{pitchscreen}{% -\section{Timestretch} -Enabling \setting{Timestretch} allows you to change the playback speed without -it affecting the pitch of the recording. After enabling this feature and -rebooting, you can access this via the \setting{Pitch Screen}. This function is -intended for speech playback and may significantly dilute your listening -experience with more complex audio. See \reference{sec:pitchscreen} for more -details about how to use the feature. -} -} - -\opt{swcodec}{ -\section{Compressor} -The \setting{Compressor} reduces, or compresses, the dynamic range of the audio -signal. This makes the quieter and louder sections closer to the same volume -level by progressively reducing the gain of louder signals. When subsequently -amplified, this has the effect of making the quieter sections louder while -keeping the louder sections from clipping. This allows listening to the quiet -sections of dynamic material in noisy environments while preventing sudden loud -sections from being overbearing. - -There are several settings associated with the compressor. The first, and most -important, is the \setting{Threshold}. The threshold is the audio input level -at which the compressor begins to act. Any level louder than the threshold -will be compressed to some extent. The maximum amount of compression, or the -quietest level at which the compressor will operate, is -24~dB. The default of -Off disables the compressor. - -The \setting{Makeup Gain} setting has two options: Off and Auto. Off means -that the compressed audio will not be amplified after compression. The default -of Auto will amplify the signal so that the loudest possible signal after -compression will be just under the clipping limit. This is desirable because -the compressed signal without makeup gain is quieter than the input signal. -Makeup Gain in Auto restores the signal to the maximum possible level and -brings the quieter audio up with it. This is what makes it possible to hear -the quieter audio in noisy environments. - -The \setting{Ratio} setting determines how aggressively the compressor reduces -gain above the threshold. For example, the 2:1 setting means that for each -two decibels of input signal above the threshold, the compressor will only -allow the output to appear as one decibel. The higher the ratio, the harder -the signal is compressed. The ratio setting of Limit means essentially a ratio -of infinity to one. In this case, the output signal is not allowed to exceed -the threshold at all. - -The \setting{Knee} setting determines how abrupt the transition is from a -non-compressed signal to a compressed signal. Hard Knee means that the -transition occurs precisely at the threshold. The Soft Knee setting smoothes -the transition from plus or minus three decibels around the threshold. - -The \setting{Attack Time} setting sets the delay in milliseconds between the -input signal exceeding the activation threshold and acting upon it. - -The \setting{Release Time} setting sets the recovery time after the signal is -compressed. Once the compressor determines that compression is necessary, -the input signal is reduced appropriately, but the gain isn't allowed to -immediately return to normal levels. This is necessary to reduce artifacts -such as ``pumping.'' Instead, the gain is allowed to return to normal at the -chosen rate. Release Time is the time for the gain to recover by 10~dB. -} |