Simple bass and treble sliders... Please?...

Posted by: fusto

Simple bass and treble sliders... Please?... - 28/02/2002 13:20

My kingdom for some basic bass and treble sliders!!

The EQ is great but I dont like having to apply these settings to my entire 4000+ song collection. Yeah, yeah I know there are multiple EQ settings. But I could spend weeks configuring each of them for a particular kind of music, and still not get it right.

I would like to be able to adjust bass and treble individually on the fly.
You know what I mean; turn up the bass for a particular song or album, and then turn the treble up for talk radio or something.
The key here is "on the fly" .
Monkeying around with the EQ while hurtling along at 80mph aint no fun.

Anybody else know what I'm talking about?

Unfortunately I'm totally unqualified to come up with something like this, so I give it to the group.
Could it be a pop up option in Hijack (Perfect!!), or a standalone app?

I know I'm probably totally missing the point of the high quality EQ, and exposing my ignorance.
But, oh well...

Could somebody please help me?
If youre in the Boston area, and you see a black VW Golf driving erraticaly at high speed, with the driver hunched over the radio, thats me modifying the EQ.
Stay away. I'm not safe.

Z~
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 28/02/2002 14:03

I agree that bass and treble sliders would be good.

However, in the meantime, while you wait, I suggest trying to use the Loudness slider in place of bass and see how you do with that. It ends up acting pretty much like a bass control, only better because it's dynamic as you bring the volume up and down.

As far as treble is concerned, I don't ever have a need to adjust those frequencies on the fly, I only ever adjust low frequencies as conditions change.
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 28/02/2002 14:16

Loudness, I guess does sort of work. But it doesnt always do what I want.
Especially at the higher end of the volume range, which I usually find myself in. (Unfortunately toaster shaped car induces massive wind nose).
I do use it when I switch from player to radio though.

Z~
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 28/02/2002 14:24

Yeah, you probably want the loudness to do the opposite of what I want it to do. I want it to completely disappear at max volume, whereas you probably want it to be more like a bass control and still have a significant punch near 0db. Currently, it sits somewhere between these two extremes.

Another reason for me to want a configurable upper cutoff point for the loudness control.

Hey, Mark, are you reading this? Is it possible that the loundess-adjustment commands to the DSP are done in the kernel? Can we alter that so the loudness curve's upper cutoff is user-configurable? Is it in there, is it easy to read?
Posted by: papinist

Re: Simple bass and treble sliders... Please?... - 28/02/2002 16:12

The treble/bass slider is a very good idea... me too see the lack of this simple controls. Maybe EQ is a lot better, but it requires some skill at audio hearing, and I'm not that kind
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 28/02/2002 16:21

Wait, hang on.... I'll bet Mark could implement an actual bass/treble slider in Hijack. I'll bet there's enough information visible in the kernel and in the DSP spec sheet for Mark to figure out how to directly manipulate the DSP's bass and treble controls.

And he's already hijacked the button press, so...

Calling Mark Lord, are you reading this thread?

And while you're playing with this, you can implement my configurable loudness cutoff.
Posted by: olfajarley

Re: Simple bass and treble sliders... Please?... - 28/02/2002 16:27

Well if your willing to buy an add on EQ or even a crossover that has output volume control that would be Ideal HOWEVER If you can not do that with your current vehicle set up then i dont know what to tell you
Posted by: hybrid8

Re: Simple bass and treble sliders... Please?... - 28/02/2002 16:43

Sounds to me like you have a hardware problem with your installation. If you need to fiddle then you've probably not selected adequate speakers for your listening patterns.

I get pounding bass when appropriate and live-sounding voice when that's called for. All without ever having to retune anything.

If you need to boost your bass at high volumes, then you're not running appropriate drivers. Or you're trying to lower the frequency of songs that were never meant to go low to begin with.

If you create a few EQ presets, you can just toggle between those much more easily than having to fiddle with bass and treble sliders. Have you tried this? You'll likely find that you have enough presets to be able to account for whatever changes you'd manually make to treble/bass anyway (most of those controls don't have many "clicks" anyway).

That's my 2cents...

Bruno
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 28/02/2002 17:07

I get pounding bass when appropriate and live-sounding voice when that's called for. All without ever having to retune anything.

Me, too, but I will say that it took months of careful tweaking of the EQ and the amp crossovers before it came to that level.

And I still once in a while fiddle with the loudess control. It tends to fluctuate between 3db and ~7db.

3db is when I'm listening alone at levels up close to 0db. 7db is when others are in the car and I have the volume turned way down and I want to hear the bass anyway.
Posted by: eternalsun

Re: Simple bass and treble sliders... Please?... - 28/02/2002 17:42

I'm with Tony here. The default "flat" sound output from the empeg sounded like ass compared to my alpine. I didn't need to tweak the alpine very much, but the empeg I had to muck with the EQ for months before even approaching acceptable quality.

Calvin
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 28/02/2002 17:51

Keep in mind that the difference between the Alpine and the Empeg is that, out of the box, the Alpine (like most other consumer CD players) has its ouput curve pre-tweaked "under the hood".
Posted by: eternalsun

Re: Simple bass and treble sliders... Please?... - 28/02/2002 18:00

Yep. When I first got the empeg it was sitting on my desk for over a month before ever getting to the car. The sound quality was wonderful going through the headphone amp and etymotics, and I got used to that. When I plugged it into the car finally, it just fell down on its face and I was pretty dissapointed. The soundstaging was loosy goosy, the bass was flat, the highs were punchy and irratating... etc. It tooks months of careful tweaking before I can actually sit down and listen for a while. There's probably a lot of people out there that would rather not spend months tweaking, and just twist the bass or treble knob and come to something sort of listenable quickly.

Calvin
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 28/02/2002 20:18

You spoke my mind exactly.

When I popped the empeg in the car for the first time I said "boy, that doesnt sound right".

I've been playing with the EQ, and loudness, and my amp gains for a couple weeks now, but unfortunately I'm not very good at it.
I usually just end up frustrated and going back to the flat setting.

In my house it sounded great, so I was really surprised at how it sounded in the car. I bought all new speakers (nice cerwin vega's) and a little better amp than I had originally (kenwood KAC748s) and replaced all the wiring.
Didnt help...

I just want to turn the bass up sometimes, and maybe turn the reble up or down a bit sometimes.
WIthout having to deal with the EQ, which to be perfectly honest kinda intimidates me at this point.

Z~
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 28/02/2002 20:49

Sounds to me like you have a hardware problem with your installation. If you need to fiddle then you've probably not selected adequate speakers for your listening patterns.

The setup I have now sounded great with the stock headunit. And I'm listening to the same music (granted in a different format). So I know the hardware is acceptable to my tastes. I just cant seem to get it to produce with the empeg.

I get pounding bass when appropriate and live-sounding voice when that's called for. All without ever having to retune anything.

I've been messing with this for weeks, and I'm still unsatisfied.
Just today I think I've almost got it doing what I want with the EQ. But even then on the way home a song came on that I felt could have used more bass. So I went into the EQ and fiddled it so it sounded right. Then a few songs later, I had to go in and set it back again. (all while driving. I'm getting really good at it! )

If you need to boost your bass at high volumes, then you're not running appropriate drivers. Or you're trying to lower the frequency of songs that were never meant to go low to begin with.

I'm not running the volume that high. I'm not trying to blow any windows out. You probably couldnt even hear the music outside the car. I just cant get it to sound right with the tools I have. I've set up the multiple EQ's and I toggle between them, but it still isnt right. And I just dont have the time to invest in sound engineering my car.
I'm not trying to win any car-sound contests. And living in Boston I have an extreme distate for the people who cruise through my neighborhood with their 150db sub-woofers that make their license plates rattle. I'm not trying to do that either.

Sigh...
My Beastie Boys are flat, and heaven forbid a song has a high-hat in it.
I'm discovering songs on a daily basis that use instruments that I had no idea were in there.

OK now I'm babbling. Off to bed!!

Z~
Posted by: hybrid8

Re: Simple bass and treble sliders... Please?... - 28/02/2002 21:21

Hmm.. I do have something some of you guys might not have. My empeg is always set at 0db and is being piped through my Clarion head unit. The output of the empeg sounds the same as that of teh Clarion CD with the exception of being slightly lower in volume. (and the voume might be closer now that I've adjusted the Clarion's AUX-IN sensitivity)

When using it at home with my integrated amp, it sounds pretty much like my CD player except not as loud (boosted voltage on the CD player most likely as Tony has also mentioned in another thread).

Right now the only thing I still want to check out is that sometimes I think I'm hearing an extra hiss ("s" sound) on some singer's words. I want to verify that it's the same when playing back from CD. It's mostly on songs that I haven't heard in a while so I can't remember if it was just that the singer had a bit of an extra lisp on those tracks

I also have to lower the gain on my rears - after playing with the L&R delay the rear seems too loud. The soundstage not only moved to the right, it's moved a bit back, so now it's like the singer's voice is coming from somewhere near the very back of my head (sometimes seems like it's around my nose. That's not too natural )

Bruno
Posted by: altman

Re: Simple bass and treble sliders... Please?... - 01/03/2002 05:16

The "lisping" sound may well be the mp3 encoding; what bitrate are you using? This is one of the well known artifacts of low bitrate mp3s.

Hugo
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 01/03/2002 06:08

Yeah, piping it through your head unit and leaving it at 0db is probably changing how the music sounds, as opposed to it coming straight out of the empeg.

Or at least I would assume so.

Z~
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 01/03/2002 10:01

Right, but note that it proves something.... the audio outputs of the empeg are not "tweaked", they are perfect. It is the head unit you're piping the audio through that tweaks the output.

The other head unit manufacturers pre-tweak their outputs so it sounds better when you first install it. I actually prefer the empeg's way of doing it, start with a flatter "starting point" and allow YOU to decide where the tweaks are.
Posted by: papinist

Re: Simple bass and treble sliders... Please?... - 01/03/2002 16:15

Right, but if you don't have the skill to find the correct settings...
I have to go to my car audio installer to tweak the amps: when am I expected to tweak the EQ, before or after?
Posted by: hybrid8

Re: Simple bass and treble sliders... Please?... - 01/03/2002 16:28

Hugo, all my own encoding was done with LAME 3.90 while it was still in Alpha, using the settings from r3mix, but without the normalization and with a minimum rate of 112kbit. I may also have increase the "Q"uality level by 1 (I'd have to go look at my pref to make sure (I'm at work right now)).

I've flagged a few songs but I seem to never have the time to go make a comparison.

Bruno
Posted by: JerryW

Re: Simple bass and treble sliders... Please?... - 01/03/2002 18:34

if you guys want to adjust your equalizer for the most accurate sound, then do what the fanatical home stereo/theatre guys do and go boy a sound pressure level meter (SPL) from Radioshack for $40 and then get a CD with test tones, rip them and play them in the car and measure the levels with the SPL meter. Those are the only tools you need to get it right. Using the parametric eq, you will probably want to flatten any peaks and maybe pull up any valleys. 5-bands of eq is not a lot to work with (I have 12 bands of parametric eq just for my sub at home), but it is better than none.

Now, accurate and "good" may be two different things depending on your perspective. But without the right tools, you will probably never get to find out what accurate means.
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 01/03/2002 18:58

Unfortunately I'm not a fanatical home stereo/theatre guy.
I'm a lazy schlump who wants to turn the bass up for some Public Enemy and then back down again for some Louis Prima.
And I would like to not have to buy anything extra.

Z~
Posted by: newguy1

Re: Simple bass and treble sliders... Please?... - 02/03/2002 20:55

Jerry(i assume) have you actually tried that?If you have ,do you adjust the levels so they all read the same db level(flat)Or do you boost the low end and hi end somewhat?Thanks
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 02/03/2002 21:36

Jerry(i assume) have you actually tried that?If you have ,do you adjust the levels so they all read the same db level(flat)Or do you boost the low end and hi end somewhat?


You try to make it as flat as possible. The idea is that with a completely flat eq you will hear the sound that the recording engineer wanted you to hear.

In practice, because everyone's ears are different and personal preferences come into play that doesn't always completely work.

The main object of equali[s|z]ation is to eliminate resonances and reinforce 'dead' frequencies to get the sound as flat as possible.

5 parametic eqs should be enough to do a reasonable job when you consider the variable Q, and the fact that wind-noise and road vibrations etc are never going to allow you a perfect AVIA-reference listening environment. Most of what makes good eq sound good is actually the removal of the biggest 3 or 4 problems (be it resonances or dead frequencies). After that, you're starting to split hairs...unless you have reference quality speakers in a perfect listening environment and perfect hearing you are going to be hard pushed to do much better.

So my suggestion is to use 4 of the 5 eqs to level as much of the sound as possible, and leave the 5th flat. Copy this to all of your eq modes, and then adjust the 5th eq in ewach mode with a very small Q factor to adjust bass or treble. (Try around 150Hz, Q=0.5 for bass and around 8kHz,Q=0.5 for treble as starting points, the small Q factor means that your boost/cut is spread over a relatively wide range of frequencies. If you feel that the adjustment is affecting too big a range, then increase Q and vice-versa.)

You need to make sure that you adjust any meter reading against the calibration chart provided with the unit. Lower frequencies read with a lower dB value.
Posted by: newguy1

Re: Simple bass and treble sliders... Please?... - 02/03/2002 22:05

You mention 5eqs but i use mine with 10 bands (only 2 front channels)I guess the same info still applies.Also,my meter does mention something about 2 different settings for A and C weighting.I know there was no chart though to adjust the levels against.Do you know if i should set it for A or C?The unit is a Radioshack digital readout SPL
Posted by: JerryW

Re: Simple bass and treble sliders... Please?... - 03/03/2002 00:04

I haven't done it in my car yet (still trying to figure out how to mount the amp) but I've done it at home. The method already described is correct, as for the setting you want, usually it is the C weighting. FWIW, the radioshack SPL meter tends to be fairly inaccurate below 80Hz, there is a spreadsheet floating around with corrections for the meter. At least there are for the analog meter and I have been told that they are the same exceot for the display.
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 03/03/2002 08:30


You mention 5eqs but i use mine with 10 bands (only 2 front channels)I guess the same info still applies.Also,my meter does mention something about 2 different settings for A and C weighting.I know there was no chart though to adjust the levels against.Do you know if i should set it for A or C?The unit is a Radioshack digital readout SPL


Maybe the digital version has onboard correction, although I doubt it. I've just checked my analog SPL meter manual. The chart is actually labelled 'response curve'. This shows what the meter will claim the levels are at for a 0dB actual level across the frequency range.

Use the C weighting. This is a flat response from 20Hz-2kHz, within 4dB from 2kHz-10kHz, and then drops off at higher frequencies.
The A weighting is designed for safety-related SPL readings.
Posted by: mlord

Re: Simple bass and treble sliders... Please?... - 03/03/2002 09:45

>My kingdom for some basic bass and treble sliders!!

I also believe this would be very handy for many owners, I don't need it here, cuz my head unit has all of that + tuner + cd-player.

But this can be implemented in Hijack, if anyone wants to try it and send me patches. The approach is to implement tone controls internally as equalizer adjustments, using tonal curves in software.

In other words, when cranking up the "Bass", the software would actually raise the EQ levels for the lower frequencies, in the shape of some nice smooth curvy thing (rather than just spiking up one or two EQ bands in isolation).

Hijack could supply the user-interface (a popup slider or two), and maintain the adjustment amounts as offsets from the settings used by the player software. I'd have to find a place to store them, maybe steal some more flash, or take over a disk sector or two, but that's easy enough if/when the time comes.

So, if somebody wants to write a couple of nice little C routines, one to adjust "bass" and another for "treble", the perhaps this will go somewhere.

These routines would just take a +/- integer as input (0 == flat, + == more, - == less), and calculate how much +/- adjustment should be made to each EQ band, using an array of integers (one for each band) to indicate the adjustments.

Once those two routines exist, we/I/somebody then just hacks into the kernel sound driver to apply the offsets to the current EQ settings, maintaining them as the player software makes it's own adjustments (from the EQ menu.. possible to use both EQ and bass/treble at once).

But don't wait for me to do this (I don't need it, my head unit already has bass/treble popups).

-ml
Posted by: tanstaafl.

Re: Simple bass and treble sliders... Please?... - 03/03/2002 12:41

In other words, when cranking up the "Bass", the software would actually raise the EQ levels for the lower frequencies,

Or perhaps better might be the software would actually lower the EQ levels for the higher frequencies in order to avoid clipping when the volume is set to 0dB.

Or perhaps not... this approach would cause the overall volume level to drop when "cranking up the Bass" so in addition to adjusting the bass/treble you'd also have to increase the volume putting you right back into clipping mode. Hmmmm...

tanstaafl.
Posted by: mlord

Re: Simple bass and treble sliders... Please?... - 03/03/2002 13:35

If we wanted, I think that the routine which actually applies the adjustments inside the audio driver could be made clever enough to center the results around 0db, regardless of player-EQ and bass/treble settings.
Posted by: bonzi

Re: Simple bass and treble sliders... Please?... - 03/03/2002 16:38

Hm, I am affraid that simple approach with correction table works only if people use EQ in simple graphics mode (i.e. if they don't change default frequencies and Q factors for each band, only attenuation/boost).
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 03/03/2002 19:48

Hm, I am affraid that simple approach with correction table works only if people use EQ in simple graphics mode (i.e. if they don't change default frequencies and Q factors for each band, only attenuation/boost).

Yeah, I've been turning my head inside out with this one all day. I think that you're probably right...the only way to do what Mark suggested would be to obtain all of the current eq settings, 'draw' the graph, add the adjustment and then factor the graph back into new eq settings that then get applied. I doubt that this is trivial to do, or desirable in k-space.

Assuming that everyone has default frequencies and Q factors in their eq settings would force users to make a choice of severely limiting their eqs or not being able to use this desired functionality.

IMO, the 'best' solution would be to overload bands 9 and 10 for bass and treble settings in 2x10 mode, or just band 5 for bass if the eq is being used in 4x5 mode.

Either have the user set up appropriate bass/treble frequencies and Q factors in these bands for all their eqs, or have config.ini/HiJack settable values that overload whatever the eq bands are set to.

Then make the dB adjustments easily accessible via the HiJack menu (lock all channels together!)

The only real issues are that you'd need to know whether the eq is in 4x5 or 2x10 mode, and to ensure that these new values stick if the user changes which of his 16 eq modes he is using. (Do you have visibility into this? Or is brute-forcing the bass/treble settings once per second an option?)

I've just played with some eq setting, and 200Hz,Q=0.15 and 8KHz,Q=0.15 seem to effect a reasonable bass and treble change.

As to clipping distortion caused by bass boost (definately an issue) I'd suggest reducing the volume as bass gets increased above 3dB boost. I don't know whether it'd be possible to change and limit the volume dynamically based upon what the current bass/treble settings are or not.
Posted by: mlord

Re: Simple bass and treble sliders... Please?... - 03/03/2002 20:52

I'm not too concerned about conflicts with Q settings and whatnot. Like probably 90% of empeg owners out there, my EQ is set completely flat, because fussing with those detailed controls is impossible when driving. Yes, I know I can park and play with it, but I don't. And probably neither do 90% of the owners.

This bass/treble is for those 90%.

Cheers
Posted by: wfaulk

Re: Simple bass and treble sliders... Please?... - 03/03/2002 20:57

If that's the case (and I agree that it is), wouldn't it be easier to just set a few EQ settings that would emulate bass/treble sliders? Some folks here could come up with some good ones. And then, maybe, have a hijack setting that would use those instead of trying to dynamically tweak them?
Posted by: mlord

Re: Simple bass and treble sliders... Please?... - 03/03/2002 20:59

For me, a simple tone control, or perhaps a pair (bass/treble), would be a heck of a lot simpler than having to also go into the ultra-complex EQ menus and create a bunch of presets. That's the idea.

Cheers
Posted by: wfaulk

Re: Simple bass and treble sliders... Please?... - 03/03/2002 21:17

I was suggesting that some nice folks might create some handy presets to distribute that would be easy to import. Then again, that's all stored binarily (it's a word now), isn't it? I was thinking that it was in config.ini, but I'm wrong, aren't I?
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 03/03/2002 22:35

HeHe, pseudocode time..



int BassdB = 0, TrebdB = 0;


if (current_eq=="Flat"){
AddHijackMenuItem(&BassAdjust,"Bass");
AddHijackMenuItem(&TrebAdjust,"Treble");

for (channel=1;channel<=EqChannels;channel++){
SetEqBand (1, BassFreq, BassQ, BassdB); /* Band, frequency, Q, dB */
SetEqBand (2, TrebFreq, TrebQ, TrebdB); /* frequency / Q from config.ini */
};
};

void BassAdjust() {
while (true) {
Key = GetKeyPress()
switch (Key) {
case "Up Button": return();
case "Knob Right": { if (++BassdB >12 ) then{BassdB=12;} }
case "Knob Left": { if (--BassdB <-12 ) then{BassdB=-12;} }
}

for (channel=1;channel<=EqChannels;channel++){
SetEqBand (1, BassFreq, BassQ, BassdB);
}
}
return(0); /* should never get here */


void TrebAdjust() {
/* Ditto. */
}




Would that principle work??
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 04/03/2002 02:14

It's too bad you'd have to go to all that trouble (offsetting the EQ) to get bass/treble.

Because I know that the DSP has bass/treble control registers built-in, and those registers are completely independent of the EQ.

Too bad there's no way to directly access them, sigh...
Posted by: dcosta

Re: Simple bass and treble sliders... Please?... - 04/03/2002 09:10

There must be a way to access them, why can't they be accessed ?
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 04/03/2002 09:57

There must be a way to access them, why can't they be accessed

Well, there probably is a way to access them. The problem is that only the Empeg guys have access to the required documentation to do so, and they had to sign an NDA to get that. Mark doesn't work for Empeg so does not have the information. Even if he did, it'd be difficult to write a Hijack modification to access the treble/bass without revealing that information (hence breaking the terms of the NDA).

So, we either wait for the Empeg guys to include simple bass/treble controls in the player software, which isn't likely to happen anytime soon given that the unit is EOL and it isn't a bug fix, or Mark kludges it somehow.
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 04/03/2002 10:05

I'm not too concerned about conflicts with Q settings and whatnot. Like probably 90% of empeg owners out there, my EQ is set
completely flat, because fussing with those detailed controls is impossible when driving. Yes, I know I can park and play with it,
but I don't. And probably neither do 90% of the owners.


That's why I suggested to use bands 9/10 and completely overload any existing settings on these bands. With a low Q factor, it shouldn't be necessary to use more than one band to effect a bass or treble slider. People who still wanted to set up eqs would still have the other bands to play with.

Anyway, I'm only suggesting solutions for fun - I also have Bass/Treble control on a separate HU..
Posted by: tms13

Re: Simple bass and treble sliders... Please?... - 04/03/2002 10:30

Bass/Treble controls could just reserve one of the presets for its purposes, overriding any user settings in it (or first checking it for flatness).
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 05/03/2002 12:02

Can I just tell you how excited I am that this is even being discussed?
I thought it was a long shot, but youse guys are real sharp.

Keeping my fingers crossed, hoping it comes to fruition.

Z~
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 06/03/2002 09:03

Ok, I'm working on it, and teaching myself C in the process.

I've got the Hijack stuff sorted to add Bass and Treble adjustments to the menu, and to control the gains.

Now I've just got to work out the format that the eqs are stored in, and figure out how to modify them. The hard stuff. If anyone has any clues, then feel free to share.
Posted by: mlord

Re: Simple bass and treble sliders... Please?... - 06/03/2002 09:41

Well, I assume you have found this starting point:

linux/arch/arm/special/empeg_mixer.c:

case EMPEG_MIXER_SET_EQ:
{
struct empeg_eq_section_t sections[20];
#if MIXER_DEBUG
printk(MIXER_NAME
": mixer_ioctl EMPEG_MIXER_SET_EQ %08lx\n",
arg);
#endif

copy_from_user_ret((void *) sections, (const void *) arg,
sizeof(sections), -EFAULT);

empeg_mixer_eq_set(sections);
empeg_mixer_eq_apply();
return 0;
}
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 06/03/2002 11:06

Yeah, found that. I'm trying to work out the format of each section. There is 2 words per section that somehow encode freq, Q, and gain. The preliminary spec wasn't any help here..
Posted by: mlord

Re: Simple bass and treble sliders... Please?... - 06/03/2002 11:17

I would guess that the frequency (band) is just the array index. But the others.. gotta dump em out as they change and see which bits are different (which you no doubt are doing already).

Cheers
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 07/03/2002 12:30

Partial success!!!!!!!

OK, I have bass and treble adjustments working...kinda. If I'm on AC power then everything is great, but when on DC trying to change the values sends the player beserk. I'm guessing I have to learn more about this ir_translation thing.

It's coming soon!
Posted by: mlord

Re: Simple bass and treble sliders... Please?... - 07/03/2002 12:43

I wonder if the EQ setup is different for DC mode (with fader and whatnot..)?
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 07/03/2002 13:05

There are two different personalities for each EQ setting, and the in-car mode has the 4-channel option....
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 07/03/2002 13:15

Sorry, I meant player as in the Empeg as a whole, as opposed to the player software..

What's happening is that the Empeg tries to toggle back and forth between aux in and mp3 when I turn the knob - turning the knob more than one click acts like pressing the 'source' button on the remote repeatedly.

Posted by: sancho

Re: Simple bass and treble sliders... Please?... - 07/03/2002 14:00

In reply to:

do what the fanatical home stereo/theatre guys do and go boy a sound pressure level meter




wouldn't a "fanatical" home stereo guy invest in an RTA instead?
--
sancho
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 07/03/2002 14:32

Problem solved.

I changed 2 things, not sure what fixed it.

Firstly, I defined FAKE_BASSADJ and FAKE_TREBLEADJ and added them to the buttons table to allow ir_translation.

Secondly, I removed the copious amount of serial debug output that I had wedged into my eq write function. (I seem to remember that serial port is slower in DC mode?)

Anyway, I have working bass and treble control. Who wants it?
Posted by: time

Re: Simple bass and treble sliders... Please?... - 07/03/2002 15:06

Sure! Where? Is it Hijack enabled?
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 07/03/2002 16:17

Buy that man a beer!
In fact... beer for everybody!!
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 07/03/2002 19:33

Ok!

hijack233-basstreb.zimage is up. (Rightclick and save!)

This is a preliminary beta - and isn't fully functional. By that I mean that you're going to have to use the player's eq to initially set some values which the Hijack-menued Bass and Treble Adjustment need. Eventually I hope to get these values in config.ini and ignore the player supplied values completely, but I need to crack the internal format for them first. It also only works in 2x10 eq mode at the moment. (4x5 mode will have a funny effect - you'll get bass adjustment at the front and treble at the rear or vice-versa, I'm not sure which.)

Note that there are 2 complete sets of eq settings, one for DC mode and one for AC mode - so you need to set these values whilst in the mode that you intend to use (or both if that's what you need).

Set the ninth band of each channel to have dB=0, f=100Hz, q=0.2 and the tenth band to have dB=0, f=10KHz, q=0.2. I think there may be a bug in the players eq channel lock code so I'd do this with left/right channels unlocked. (I'm still looking into that.)

Exit from the eq menu, go into Hijack and test away
You can tweak the f and q values if you think that the ones I've provided don't suit your needs. Keep q small (under 0.3) so that the adjustment is smooth and wide across the frequeny range.


Any bass/treble level adjustment gets lost when the player is rebooted. (only the level, not the f and q settings).
The bass/treble will only work when the selected eq has the f and q values set appropriately in bands 9 & 10.

You should be able to set ir_translations to call these menus. Pseudo buttons are named "BassAdj" and "TrebleAdj".
You should also be able to do the other wonderful Hijack stuff with these: Remove from menu, add to Popup menus etc. This is untested, and any feedback on these is welcome..(especially feedback like "ir_translation works for Bass and Treble menus" )

I'm going to keep working on this to try and get those values in config.ini so we can ignore the players eq settings completely, see if we can store the levels over a reboot (is this important enough to warrant the flash usage?), and generally work it a bit more. Then I'll send Mark a patchfile

...and that beer will hopefully be gratefully accepted at the Boston Owners meet - it'll help offset the cost of buying Mark's!
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 08/03/2002 13:29

I'm probably missing the obvious, but I cant figure out how to do this:
Set the ninth band of each channel to have dB=0, f=100Hz, q=0.2 and the tenth band to have dB=0, f=10KHz, q=0.2
I can see when I'm in the eq mode I can change the DB levels which in turn changes the q level, but how do I independently change them to the specific levels you mentioned? Is there some other method than just turning the knob, that I'm missing?

Z~
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 08/03/2002 13:33

Yes. You can independently set the Q and band frequency (hence the term "parametric" to refer to this equalizer). Please refer to the button guide at www.riocar.org to show you how to select those parameters.
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 08/03/2002 13:55

OK, I'm dumb. My co-worker showed me the error of my ways. Thanks to you Tony too.

This works great!!!

(cue the rays of sunshine, ethereal music and release the doves)
I'm gonna go play with it out in the car.

With this new functionality I will no longer be endangering the lives of my fellow motorists while playing with the EQ and driving.
You have saved hundeds of people from certain traffic related trauma.

I'll give more feedback as I play around.

Z~
Posted by: fusto

Re: Simple bass and treble sliders... Please?... - 08/03/2002 14:22

I have another question about the bass treble thing, but since my wish has been granted, should I move this thread on over to programming? That way those who read that thread who maybe dont read Wish list will be in the know.

Is that OK? I dont want to do anything inappropriate.

Z~
Posted by: tfabris

Re: Simple bass and treble sliders... Please?... - 08/03/2002 14:24

Yeah, God forbid anyone would do anything inappropriate on this BBS.
Posted by: Nosferatu

Re: Simple bass and treble sliders... Please?... - 08/03/2002 14:25

Is it me , I cannot save your file ....

????
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 08/03/2002 14:29

You have saved hundeds of people from certain traffic related trauma.

Anything I can do to improve Public Safety.
Posted by: genixia

Re: Simple bass and treble sliders... Please?... - 08/03/2002 14:34

Err. Dunno.

I know that it is there and has permissions set correctly.
What OS are you using? (Does it support long filenames?) Do you have enough free disk space? Do you have write access to the directory that you are trying to save it too?

I'm quite certain that the problem is at your end - Fusto managed to download it

Fusto,
I've been meaning to take this over to the Programming forum anyway..go ahead
Posted by: Nosferatu

Re: Simple bass and treble sliders... Please?... - 08/03/2002 14:37

I 'only' have your site unreachable ....