Ipod classic 6th generation output level too high

[heuboda]

Hello,

so far I am new here. I am glad that there are people developing this software and also helping each other. Last week my HD broke at my Ipod classic 6th generation.
I replaced it with an 256GB SD card and I had to find out that not the hole amount of memory is supported by Apple. Thanks to RockBox I am now able to have about 240GB of memory at my Ipod. Unfortunate my external DAC don't get any signal over the cable. But I have to live with that.
So I have to use the headphone jack, but even with -60db it is way to loud to listen. I have not done anything at the EQ mode. But I found out that in the EQ mode I am able to have an preamp setting of -24db. It is better now and I can listen music, but sometimes even this is too loud. The Ipod shows me the speaker signal with an cross.
May one of you have an idea what is wrong. Buy the way I am using the "ClassicRockBox" from this homepage:
http://www.tarkan.info/20140804/tutorials/howto-install-rockbox-on-the-ipod-classics
At the RockBox.org homepage I couldn't find my Ipod classic 6th generation model.
Thank you for your help ...

[saratoga]

What headphones are you using ?  -60dB is an extremely low signal level.  Its hard to believe you'd want to go lower than that?

[heuboda]

Hello,


thank you for your answer. I cant believe that the -60db are true. I am using the Audio-Technica ATH-CM700Ti. It is so loud that if I have both headphones on, that after a couple of minutes I have to put them off. So I believe that it cant be -60dB. I will try to organize original Apple headphones. I will let you know if I have tried them. But I guess there will be not much difference.

[[Saint]]

Something has to be very wrong here.

I can't exactly say what, but, something is very wrong.

You did state that you had modified the device internally, so it is possible that you have damaged the hardware in some fashion.

Not only should -60dB not be intolerably loud, it shouldn't be perceptible, at all. -60dB is functionally equivalent to "mute", inaudible.

The monitors you're using are of no consequence here, I have a range of monitors of varying degrees of precision and response (my usual "daily driver" monitors being UE18 Pro full costom in ear monitors, and not a one of them behaves in such a fashion. I too, for what it is worth, use a modified iPod 6G (several in fact), ranging from 128GB compact flash to 512GB mSATA, and I do not see such an issue.


[Saint]

[saratoga]

thank you for your answer. I cant believe that the -60db are true. I am using the Audio-Technica ATH-CM700Ti.

Those are about 118 dB/Vrms, and the iPod puts out almost 1 Vrms at 0dB, so you would be listening at a maximum volume of 58dBA, or roughly normal human speech volume.

Are you sure the volume is actually working?  If you change it, does the loudness change?

[heuboda]

Right, something is very wrong. It must be either it is a SW or HW problem. I am able to adjust the volume and I hear some different, but not that much, because it is already very loud. And if I am in the EQ settings, I am able to adjust another -24db in the preamp settings. With this setting I am able to hear like before the modification. But still I cant go to zero. So for listening in bed it is still a little bit too loud with the additional -24db.

I am from the HW side, so yes, it could be something wrong in the HW. I will double check and let you know. Thank you for your help so far.

[saratoga]

You are using the headphone jack and not line out correct?

[[Saint]]

You are using the headphone jack and not line out correct?

<snip> Unfortunate my external DAC don't get any signal over the cable. But I have to live with that.
So I have to use the headphone jack, but even with -60db it is way to loud to listen. </snip>

Right, something is very wrong. It must be either it is a SW or HW problem.

It isn't impossible that there's some hardware variant of the iPod Classic that we haven't yet seen, substitution of hardware in mass assembly lines isn't entirely unheard of, but I would think it to be unlikely.

Of course, the acid test, would be to restore the original firmware and see if the issue presents itself there as well.

If it does, since the original firmware is wiped out completely on the iPod Classic variants (since dual-boot isn't currently supported the freemyipod team wipes out the firmware partition on the disk to recovery ~200MB or so of space for the user), you will have your definitive answer.

Restoring the original firmware on an iPod Classic is a very trivial business. Simply force the device into DFU mode as you did for the initial install, and plug the device into your host system with iTunes running. iTunes should detect the "damaged" iPod firmware, and offer to restore the device.

If this does not happen, please let us know so we can help you to work around this.


[Saint]

[heuboda]

Hi folks, thank you for having the idea to install the original OS back again. With that everything works finde. The volume is like it should be. I would let the original OS on it, but instead of having 256GB (because of SD card) I have only 127GB. And because I cant live with that, I would like to have Rockbox on the Ipod. If you have any idea how I can control the volume, that would be very great...

[heuboda]

Unfortunate nobody seams to have an idea about my problem. I guess the only solution is to put back the original software and use a 128GB SD card. Thank you for your help so far ...

[Nine]

Hi there, I'm new on this forum, just have recently discovered Rockbox. I've never ever posted on a forum before so I don't know the procedure. You'll have to forgive me for hijacking the main poster. I too, have a 6th generation Ipod classic. My problem is that the sound difference from -60 to -59 dbs is too vast. I have very sensitive ears so I can only listen at about -59 dbs but I find this too loud and -60 is too low and it seems like there isn't a major difference between -59 and -58 dbs. I've tried various earphones, all feel too loud. Is there a way to tune this? Is this a bug. Can I get a frequency just meandering between -60 and -59. I know I must sound like Goldilocks (porridge is too hot, porridge is too cold) but please get me to the just right setting. After 30 - 60 minutes of listening to music at -59 dbs, my ears just hurt. The lowest sound setting on my old ipod firmware was just right for me. Not too low and not too loud. 

[13grife37]

(...)I have very sensitive ears so I can only listen at about -59 dbs but I find this too loud and -60 is too low and it seems like there isn't a major difference between -59 and -58 dbs. I've tried various earphones, all feel too loud.(...)The lowest sound setting on my old ipod firmware was just right for me. Not too low and not too loud.

Well it seems like you really have sensitive ears... because i know nobody who listened to music at the lowest volume of his IPod. So I think no, this is not a bug. It is really quiet down at -59 dbs, I could use my speakers as earpods then... So if at that low range you want more customizability the only thing I can think of are headphones that have their own volume modificator that doesn't send a digital signal to the device but instead just lowers the volume that is put into it. Then you could try maybe at -57 dbs and change the volume of the headphones.
Bad thing is: I don't know any really good headphones with that feature. The only ones I have are Computer headsets.
I have a headset from Logitech for gaming purposes:
http://www.amazon.com/Logitech-981-000537-G430-Gaming-Headset/dp/B00CJ5FPUE/ref=sr_1_36?s=pc&ie=UTF8&qid=1430473084&sr=1-36

[[Saint]]

It might be somewhat interesting to get hands on this device, or a device that fails in a similar way.

I have a feeling that this device is either:

A - Genuinely defective in a subtle way that affects us, but not the original firmware.
or
B - An as yet unseen internal hardware variant.

Of those two possible scenarios, I think we may be dealing with B.

I find it absolutely impossible that anyone could possibly perceive -59dB as too loud. With isolating in-ear monitors, that is going to be quieter than usual happenings and background noise events from usual everyday life.
Something else I just picked up on is that OP states that -60dB is too quiet, that's odd, because that should be the functional equivalent of mute. It should be completely inaudible.

It would be interesting to see the HW info in the OF debug screen, but that would require restoring the device to stock.


[Saint]

[Nine]

Thanks for the reply guys. I reverted back to my old ipod firmware. I don't know if it's psychosomatic but I find the volume adjustment better on my ears. I have another problem though. I know that this has nothing to do with topic or Rockbox for that matter..Well it kinda does. One of the reasons I reverted back to my old firmware was because my battery life was acting erratic. It would be full but after thirty minutes of listening, it would empty out, especially if I scrolled through my files. It would shut down..Usually I'd give it a break for a minute or so then start it up again. I read up on battery types and changed it under settings to the battery that seemed to match the hardware on my ipod. This seemed to have no effect whatsoever. I love Rockbox. It has so many pros but I felt that in this case the cons (sound and battery) seemed to outweigh them. So I'm back on my ipod classic 6g 2.0.4 firmware. I've had to restore my iPod at least 5 times since last week. My library is 90 gbs big and I like to sync everything, especially since I have 148 GB of space free on my iPod. I found that if I tried playing certain songs, they would skip and my iPod would crash, it would tell me to connect to a power source. I'd try that old trick...Reset or wait a while and switch it back on. I'd be very lucky if it worked. I tried adding less music, about 11000 songs. It was working fine till I tried using one of my auto playlists. To cut a long story short, I found that if a playlist uses shuffle, my ipod crashes and I have to restore. If I play all my songs, or shuffle through them, my ipod crashes. So I can only use a percentage of my space and I can't shuffle. I have terrible OCD and I'm a completionist. I find this very hard to accept. I've run diagnostic scans and my iPod harddrive seems fine. It could be my battery though. The problem is most probably hardware related. I'm nearly certain of that but I don't want to go through the process of replacing parts. I've wasted too much time on customizing my iPod, I'd be happy to get a new iPod with the same size specs but that's nearly impossible without employing a small fortune. Sony is releasing a new MP3 player. It looks awesome and has 128 gbs of space but is expensive as hell. Do you guys know of any 160 GB click wheel iPod alternatives?

Anyway, do you guys have any quick fixes or advice.

[[Saint]]

The reason why the setting you changed seemed to have no effect whatsoever on observable battery life, is because this setting has zero effect on observable battery life.

This setting adjusts a modifier for the estimated runtime remaining, which is something that is never usually displayed to the user anyway unless they specifically go looking for it. It pays to note that the calibration for estimated runtime is way off on this device anyway, meaning it wasn't ever accurate to begin with.

I am slightly confused, because you state at first that you acknowledge that the battery has nothing to do with Rockbox (because it doesn't), and then you go on to list battery under Rockbox as one of the flaws.

The symptoms you describe quite clearly describe failing battery chemistry, this is not something Rockbox has any control over.

If it seems to you as though this device ports has many problems, you are right. It does. But this is one of the reasons why installation of Rockbox on this device is not really officially supported at all*. That might make you think "Wait, what? But I installed Rockbox just fine!", to which I would say "But, where did your bootloader come from?".


[Saint]


*we only provide the binary, and a means to update an existing installation, but not any way of booting the binary provided