The Apple diyMod: My Take on the Famous iMod [56k killer] Featuring 3G, 4G, 5G and nano 1G!
Feb 24, 2011 at 2:53 AM Post #2,371 of 3,220


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Look here. Alternatively, you can solder the wire to the one on the headphone jack. You really should pick up a DMM if you're going to be working on electronics though. They're only $10 at the local hardware store, $20 max for a sufficient model. It'd save you a lot of trouble in the future. I'm assuming you can afford it since you have at least two iPod 5Gs and a 240GB hard drive. A small investment like this will go a long way.


Thanks for the pics, they're really helpful!
 
I went out and picked up a multimeter pretty much as soon as I realized that I'd be an idiot to be soldering and playing with expensive electronics without one :)
 
Feb 24, 2011 at 3:15 AM Post #2,372 of 3,220
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AT0MAC:
 
I don't think Joneeboi was trying to insult you. If you're referencing "It seems you lack the understanding of the basic premise..." you shouldn't take that as an insult. He's been more than helpful to all who've asked questions in the thread.
 
For more pictures, check out the gallery: https://picasaweb.google.com/joneeboi/4GPhoto#
No words, but I think you can figure out what to do, if not, then ask~
 
Someone please correct me if I'm wrong, but I'll do my best.
a) If you're doing an iMod, that means that from the DAC, you'd be wiring to your capacitors, then to the headphone jack (DAC > caps > headphone jack). I've not seen any pics of this (probably one of the earlier pics in the thread where the bandwidth was exceeded).
b) If you're doing a version of a DIYmod where you want to keep the headphone jack stock, then you'd wire DAC > caps > inductors (check pics for exact ones). However, this would only give you the improved SQ from the dock port. The SQ from the headphone jack would still be stock.
 
As far as I know, the only purpose of this mod is to have a high quality line out that would have to be combined with an external amp. The whole point is to bypass the iPod's internal amp/volume attenuator which is lower quality.


I think that this is what you are correctly saying but to be clear:
 
None of the DIYMods, iMods, or Whipmods improve the direct headphone driving ability of the modded iPods. Some of the mods do convert the headphone out to a line out but the effect is always the same:  an improved line out for usage with an external amplifier, not an improved headphone out for directly plugging in headphones.
 
Feb 24, 2011 at 10:41 AM Post #2,373 of 3,220
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The whole point is to bypass the iPod's internal amp/volume attenuator which is lower quality.


Close, very close, but no cigar, junkers. There isn't a true, classical amplifier in the Wolfson in the manner that many people think. The source level is actually line level, like other external CD players or DACs. What the headphone jack source does is it digitally attenuates the signal inside the DAC, and then it passes it through the passive filter to the headphone jack. The same goes for the line out, except it doesn't attenuate the signal at all. Turn the volume up on your headphone jack and it should sound about the same as the line out. You could effectively use the headphone jack if you wanted by turning up the volume to the max.
 
AT0MAC:
 
If you read past that one sentence, you'll find your answer. I prefer helping people to understand what they're doing  instead of just helping them mindlessly modify their expensive equipment by just telling them what to do. Even if the iPod photo's guide page is really sparse, you can read the iPod click wheel's guide because they are both really similar. Here is my amended response:
 
You replace the series capacitors of the line level output of the Wolfson CODEC found in the more popular iPods. These types of DACs put DC on the electrical output signal, so you need to block the DC from getting to your headphones or speakers. If more than 20mV reaches your dynamic loudspeakers for enough time, they will be destroyed. One way of blocking that DC is by putting a capacitor in series with the signal, or putting it through a high pass filter. The high frequencies are passed through, but the low frequencies (DC is basically a 0 Hz signal) are attenuated. We want a high pass filter that only attenuates subsonic signals (so one can hear all the music), so we set a corner frequency, aka -3dB frequency, to somewhere below 20 Hz.

 

The iMod/diyMod converts that high pass filter into a higher quality, audiophile-grade filter by replacing the stock capacitors with higher quality ones. Since the signal passes through the capacitor entirely, it can't degrade the signal by much. The iMod turns your headphone jack into a line out, but that's undesirable because you can no longer use your headphone. People have put up with this before, but I think it's silly. The diyMod shows you how to make whatever set up you want, including replicating the iMod. Preferably, you'd convert your dock line out to a diyModded signal, with or without the capacitors already in series. You can put the capacitors into the iPod, such as in the 4G click wheel and 4G photo, or you can put them in a capped line out dock. Since you have the room, you can put the capacitors inside the diyMod. You can make the line out dock the diyModded source, or you can do what the iMod does and convert your headphone jack into the aforementioned source. Your described scenario converts the line out dock into the diyMod signal.

 
Feb 24, 2011 at 5:26 PM Post #2,374 of 3,220
Ok, thank you joneeboi.
Please help me clear out a few things im still wondering about:
 
What is the difference in removing the Z-caps at C86/C84 and solder onto those joins or use the C921 and the one next to it?
 
I understand why the C921 and the neighbor is marked in this picture, but what is the L20 and C924 marked for?
https://picasaweb.google.com/joneeboi/4GPhoto#5353577569161996210
 
So if I solder wires onto the right joint at C921 and the neighbor, into a pair of capacitors and back up to L2 L3 - have I then made the iMod with fixed headphone out or is it infact the DiyMod with variable headphone out?
 
Last, if it's the DiyMod, what would happen if I sat the iPod into a dock like maybe the Arcam irDock?
 
Feb 27, 2011 at 1:09 AM Post #2,375 of 3,220
Quote:
Ok, thank you joneeboi.
Please help me clear out a few things im still wondering about:
 
What is the difference in removing the Z-caps at C86/C84 and solder onto those joins or use the C921 and the one next to it?
 
I understand why the C921 and the neighbor is marked in this picture, but what is the L20 and C924 marked for?
https://picasaweb.google.com/joneeboi/4GPhoto#5353577569161996210

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C84/C86 relate to the iPod 4G click wheel, but you are working with the iPod 4G photo. The latter was released later with the colour screen, and their logic boards are very different with respect to the diyMod. Don't remove any components. Solder the wires from the north of the components to your diyMod capacitors, then to the dock pins L2/L3. C924 and L20 are marked by the user that submitted the pictures, not me. I forget why they did that.
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Quote:
So if I solder wires onto the right joint at C921 and the neighbor, into a pair of capacitors and back up to L2 L3 - have I then made the iMod with fixed headphone out or is it infact the DiyMod with variable headphone out?



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[size=medium]
That's the diyMod with variable headphone out. L2/L3 are the audio out dock pins. If you want to make the iMod, you're going to have to solder the wires to the headphone jack. And if you want to do that, you're going to have cut the original signal to the headphones, much like this one for the iPod 4G click wheel (it'll be different on the 4G photo):
 

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[size=medium]
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Last, if it's the DiyMod, what would happen if I sat the iPod into a dock like maybe the Arcam irDock?



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It would depend on the design of that particular dock and diyMod. If you mod it the way I describe earlier, then you won't have a problem with DC potentially destroying your equipment. Check the DC content of the electrical output signal if you can. If you choose to do a diyMod without internal capacitors, it would be more problematic. If you do it the way I recommend, then you'll have no problems with docks.
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Mar 4, 2011 at 10:09 AM Post #2,376 of 3,220
For those who did the mod, was the SQ change noticeable with regular male/male 3.5mm cables or using a generic LOD to connect to your amp? What was the quality of the wires/solder that you used? Will I hear any difference using regular copper wires, regular solder, using a FiiO LOD? I was just curious as to how steep the price/SQ improvement curve was here, and if it would be worth it to do even with sub-optimal materials.
 
Also, what are the pros/cons of a headphone jack line-out vs a LOD line-out (considering that the wiring was done correctly for each)? I figured everyone would want to use the headphone jack line-out so that they can charge while playing, but most people seem to like the LOD method (I'm talking specifically about the 4G here since the caps can fit inside the iPod itself). Is it because they already have a high quality LOD cable?
 
Mar 4, 2011 at 11:10 AM Post #2,377 of 3,220
Different capacitors sounding very different been discussed MANY times and is something everybody basically agrees on.
Different wires, and especially something like solder is always getting trashed back and forth, some say no difference, some say big differences, all say the others are crazy.  Make up your own mind.
 
I won't get into the last question, too many things to discuss.
 
Mar 5, 2011 at 11:07 PM Post #2,381 of 3,220
Hi guys just want to share my DIY imod on a 5th gen 60gig ipod video.
 
used @ 47uf non polar BG NX
 

 
used a teflon insulated silver wires fastened by high temp tapes. The hardest part is routing the wires through this small area.
 

 
 
the caps are inside the case so that i can use any LOD.
 

 
added some CF sticker to the faceplate since i got it used with minor scratches in front.
 

 
So far i'm very happy with the SQ 
L3000.gif

 
 
 
Mar 8, 2011 at 12:01 PM Post #2,383 of 3,220
Quote:
For those who did the mod, was the SQ change noticeable with regular male/male 3.5mm cables or using a generic LOD to connect to your amp? What was the quality of the wires/solder that you used? Will I hear any difference using regular copper wires, regular solder, using a FiiO LOD? I was just curious as to how steep the price/SQ improvement curve was here, and if it would be worth it to do even with sub-optimal materials.
 
Also, what are the pros/cons of a headphone jack line-out vs a LOD line-out (considering that the wiring was done correctly for each)? I figured everyone would want to use the headphone jack line-out so that they can charge while playing, but most people seem to like the LOD method (I'm talking specifically about the 4G here since the caps can fit inside the iPod itself). Is it because they already have a high quality LOD cable?


My big point with the diyMod is the value in certain parts of the audio chain. I know some people swear by certain aspects, some will pay hundreds of dollars to get it, but ultimately, you have to hear the difference. It might sound a little different, but the diyMod isn't quite the same as changing your headphone or your amp. I think wires and connectors are fairly insignificant on the audio pyramid. Honestly, if you want better sound quality, you should spend more money and attention on your headphones and amp, sometimes the source comes into play. I won't directly address any of your questions because my whole point is that they are irrelevant. I think it's a waste of your time to split hairs on such matters.
 
I will address the last question though. Go with the LOD. You want the option of listening to the music unamped or undiyModded. Charging while listening will introduce a very noticeable hiss when amped, diyMod or not.
 
Mar 9, 2011 at 4:37 AM Post #2,385 of 3,220
good work, big long aerials though, do you get any noise? 
 

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