SSD in iPod and trick to make sound quality really outstanding

[WindowsX]

Finally, I managed to find iPod Video in desired condition (anything better than ragged ones) and replaced internal storage with 64GB SSD ones. I notice significance difference in sound quality but I could hardly say it's really that good for counting as improvements. I made some research and finally unlocked this.
 
1. Download iPod Wizard 1.3 from http://www.getipodwizard.com/download.php
2. Open iPod Wizard using "Run as administrator"
3. Set "Edit Mode" to "iPod" and click on "Load iPod Firmware" button
4. Click on "Tweaks" Inside there, select "Disable caching" and click on "Apply Tweaks"
5. Finally, click on "Write" and then "Eject" to see dramatic improvements of sound quality
 
The reason why disabling caching improves sound quality is because the reduce of hardware I/O latency by removing disk cache buffer from bit-stream chain reducing induced jitter effects improving performance in audio playback. However, the drawback is possibility of dropout during playback (which is rarely be found) and increased power consumptions.
 
Since SSD has no moving coil and consumes lower power so making SSD always active without buffer will consume only additional 0.5W or less per hour. You can try this tweak in normal iPod though but improvements of this tweak in SSD is far greater than ones without tweaking.
 
P.S. This tweak works on normal iPod firmware only. If you're Rockbox users, you don't need to apply this tweaks. However, the improvements of sound quality could even rival against Rockbox

 

[High_Q]

hmmm.  I wonder how my 5.5gen ipod is affected by its mechanical drive.  SSD does sound like it would reduce jitter compared to the mechanical drives since solid state would be quicker and reliable.  I need more info on jitter effects caused from HDD memory, but then again I'm sure the music is cached before hand, its not like its being streamed while playing. So jitter effects should not be effected by HDD.  Does that sound reasonable?

 

[WindowsX]

It's the opposite. Caching brings latency from buffer and that's even more jitter. If you ever heard of discman with buffering to prevent drop out from vibration, improving buffer length will degrade the sound making it less airy and less transparency.

 

[miku39]

That is odd, if I remember correctly there is a jitter reducing scheme using some kind of memory buffering.
And I thought the benefit of caching is reducing lag to the other side of the cache which will provide smooth streaming of data
Well then one can argue that the SSD interface (SATA?) is less jittery than the RAM interface, who knows.

 

[WindowsX]

RAM is better but ssd -> ram and ram again is less than ssd -> ram alone. Buffer is something needed when ones cannot work right without it. If you use normal hdd, it needs buffering to store music files so iPod don't need to spin harddisk all the time. It has pros and cons though. For SSD, the issue is resolved as SSD doesnt spin and doesn't consume that much power when operated.

 

[TekeRugburn]

I didnt get most of that, but i just installed a 32gb compact flash card in a ipod video 5th gen.  loads a lot quicker and i use rockbox....prefer it over stock firmware.

 

[tds101]

The SQ is not affected by installing an SSD/cf card. Only read time and battery life, and the reliability factor of no moving parts,...SQ has nothing to do with it. Saying it does shows a complete lack of understanding of the tech.

 

[Jonnip]

Quote:

The SQ is not affected by installing an SSD/cf card. Only read time and battery life, and the reliability factor of no moving parts,...SQ has nothing to do with it. Saying it does shows a complete lack of understanding of the tech.

Totally agree with you, was thinking this as i scrolled down the thread
 
 

 

[WindowsX]

Sighs. Did you actually try to compare between normal iPod Video and SSD with this tweaks side by side? If you use decent headphone or portableamp+good cable, you should be able to notice. There're also couple of computer audiophile replacing hdd to SSD and get dramatic changes in SQ.

 

[TekeRugburn]

i always thought a digital signal is digital....either its there and works or not there and doesnt

 

[WindowsX]

Then all CD transport should sound the same, powercord should make no difference yet they all do. I use Esoteric's transport and DAC and heard most hiend rigs in market so I can guarantee that digital signal isnt that accurate. Some even claim that putting iPod on tip-toe improves SQ.

 

[TekeRugburn]

isn't powerchord just to have a steady input of power? flux in power affect internal components....right?  

 

[WindowsX]

It does but not all. That's much I can say before the topic get carried away. Whether SSD on iPod improves SQ or not, it saves battery and become faster.

 

[High_Q]

You are right, but there is something called jittering.  It has to do with the timing of the binary information being transported.  Since, DSP is being done in descrete time, when each bit is being converted to analog, The frequency should be identical to the frequency of it how it was converted to digital. In the worse case scenario, the timing is not exactly cyclic by what ever T is in 1/T.  But, I have to look into that, I need to do some research on this.  So there maybe be too much variations in timing between the bits, opposed to how the music was compressed in which the bits were timed identically by T.  If they are not identially timed T for each bit, and converted to analog, it would not get the analog signal intended.  So a good DAC would prevent that, not a memory source.  DAC controls the timing.  So, OP, lets not confuse people here, unless I'm not understanding something here.  I agree SSD is fast and reliable, but to say it ups the SQ is far fetched.  Reliable DAC, linear AMP, headphone without distortion is what we need.
Quote:

i always thought a digital signal is digital....either its there and works or not there and doesnt

 

 

[WindowsX]

Well, I understand the logic behind that but reality isn't what we think it is. If you use low-end equipments, you have one idea, higher ends bring up more experiences and knowledge behind for making it closer to ideals. Fundamental knowledge tells us what it should work from design but doesn't describe how everything works. You don't need to believe it but just realize that no one knows everything.