The Apple diyMod: My Take on the Famous iMod [56k killer] Featuring 3G, 4G, 5G and nano 1G! - Page 173

Well done matey, sorry I missed your post, been partying hard.... :)

 

That's a tidy job, especially as it's your first, well done.

 

Difficult to tell but the cap leads may be sitting up on the top of adapter's foam pads....

 

Don't worry about the cap value too much, 4.7uf is more than enough, even if you take into account a low 10K  input impedance of the following amp.

Again, cap voltage is not going to factor, you can't buy 'audio grade' caps with a max voltage low enough that will fit in there....

 

 

Nope, ALL capacitors will bock DC up to their rating.

Thanks, my man...

If by this you mean why it wouldn't close?...

""Difficult to tell but the cap leads may be sitting up on the top of adapter's foam pads...""

 

Yeah, I moved things around a bit and then it closed up fine. However, the more I listen I am not liking something in the sound, there is a weirdness in the midrange and some affect on the lower end that isn't working for me so I am going to pull those film caps and try the Silmic electrolytics with a slightly higher rating. Maybe I am getting some bass roll-off and also maybe I just don't like the sound of the film caps...

 

It seems most that try those electrolytics are happy with the result so I'm going to give it a shot. I will report back after giving them a try.

 

Do you have any opinion on sound differences between electrolytics and film?

 

Thanks again! 

Edited by thegrobe - 1/2/13 at 10:16am

Hey buddy,

Yeah, I was referencing the closing problem.

Sound differences are way more subtle and hard to nail down but the film caps can be more bass heavy if anything.

If you are getting anything 'strange' I would put it down to dry solder joints or wire routing rather than cap type.... certainly isn't roll-off, maybe even cap placement?

Try opening the back and moving the caps onto the top of the adapter away from the transformers/inductors

But on a more subtle note...I have noticed over the years that film caps do seem to burn in though, I don't really follow the logic but they certainly do change over the first few hours.

 

EDIT: When you put the pins back in they didn't touch the PCB base pads?.. just checking...

Edited by no_eye_dear - 1/3/13 at 4:26am

Hey, thanks for the reply.

I did notice a very significant (to me) ..(and positive) change in the film caps after just a few hours.

 

I took it apart yesterday, actually, and changed the caps to Silmic II's and placed one in the space next to the CF card, and the other between the CF card and battery. Also moved the wires around a bit. I already find the sound more preferable - smoother...perhaps the location of the caps or wire routing was an issue?

 

I am pretty certain the joints aren't dry - but that would certainly cause problems. Anyhow, the new configuration is more preferable.

 

Pretty sure the joints are good, solid, and shiny, not dry. The pins are certainly isolated from the pcb and locked in place with some hot glue. I am going to do more messing around with this of course,  so I will again try the film caps moved away from where they were next time around and give it a go. Really, this is all fun for me just messing about with it. 

 

One other thing: just being curious, I measured the line out and noticed a little touch of DC leakage - Never tested this with the film caps. A stock 6 gen Ipod I have around I get a reading also of about .005 volt DC on the line out, the mod gets up to about .012 give or take. Is this a concern? I checked the headphone out on my amp and get nothing - so there is no DC getting through to headphones but ....thought it worth asking

Edited by thegrobe - 1/3/13 at 8:51am

Interesting one that... you obviously have the caps the right way around or you would be getting 1.5V 

Do you measure it when connected to your amp? Is there a chance of some bias current coming off the front end of the amp?

Then again, a millivolt or two is pretty damn insignificant anyway....

yeah, to be honest I don't even know if I'm measuring it properly. I'm just using cheap multimeter and measuring across the line out ground and either left or right signal when it's playing and not connected to an amp. The measurement rises and falls a tad as it plays.

a bit of googling came up with some caps can leak some DC. like I mentioned, I'm not too concerned, there is no reading by the time the signal passes through my amp, maybe it's absorbing that little trickle. Just curious.

I'm going to switch back to the film caps in a week or two and try placing them in a different part of the case (to see about my aforementioned "weirdness“)...I'll see if I get any reading off those.

Today I finally opened my ipod 5g and asked somebody to help me do the mod on it. We just rewired from L2-L3 to the empty dots below c84 and c85. We didn't remove anything. 

I have several capacitators I want to try, but my idea of fitting them inside a dock is a no-go, because they are too bulky. I don't know how people put the ELNAs inside a dock. 

 

Anyway, I have the ELNAs 47uf5v, NIchicon Muse 47uf50v, Nichicon Muse BP 47uf25v, ROE 47uf10v and a couple of Sprague VQ 0.1uf 100v. The only ones that might fit inside the dock are the ROE. 

 

While I try to figure out how to make a dock for the Nichicon and the VQs, can I use the LOD with my Fiio e17 as it is now, or I risk to damage something? 

I'm a bit confused..did you pick up the signal from the "Z" caps by the DAC? or just from L2/3? Could you post a picture of what you did? Best to bypass everything for a pure signal

 

I have recently been experimenting with a bunch of different caps and have found wima polyester caps good and wima polypropylene even a bit better (but they are way too bulky - sounds great though!) As far as the electrolytics you have, the 47 uf are way way  more than sufficient. Don't use the .1 uf. Not enough. Here's why:

 

There are two ways to look at the calculation to choose a capacitor. There is the -3db point (corner frequency) which as a bare minimum should be under 20 hz. Then there is an optimal frequency, which helps rule out any phase distortion, and this is around a 10 times higher frequency, which you also want to keep under 20 Hz but it isn't as important. So assuming you have 10k resistance in your amp, to get a -3db point under 20hz, you want a .8 or higher uf rating...For the optimal value, which keeps any phase irregularities under 20 hz, you want a 8uf capacitor this will give you a -3db of about 2Hz. 

 

Any higher input impedance on your amp (50k, etc) changes this capacitor value needed (to a lower uf rating)...so in any circumstances, 1 uf is minimally sufficient, 8 uf is preferred. Anything higher that 8uf, in any configuration is complete overkill. 

 

I wouldn't try using it with no caps.. you could damage your amp or headphones. .If you were dying to try you could run it through your amp and use a multimeter to make sure the amp is perhaps blocking any DC from going to the headphones, but I don't know if this may damage the amp. Better just to do it right.

Hi, I'm planning on doing a Diymod to a 5G iPod video that's served me well for years. I've been over the thread here, and have no fear about the soldering involved (my first job out of school involved soldering components under a microscope for use in classified military hardware) but I'm a total noob when it comes to actual iPod mods (never even cracked one for a battery swap)

 

I'd like to outline what I have in mind and see if any of the experienced Diymodders here can see any holes in the plan.

 

What I have planned is to convert the iPod to CF first. I have Tarkan's adapter enroute, along with the rest of the parts to do that. I've also got a couple varieties of quality caps on order, plan is to use the extra space freed by the CF mod to fit these internally.

 

Now, my understanding is with the caps installed internally, a regular dock connector should work. I frequently use the iPod in my car audio system, with the Kenwood dock/control cable for their front end units. Would like to maintain that compatibility. I did come across one thread (elsewhere, not on this board) swearing that doing the diymod would disable the ability to use external control from a head unit. I don't understand this, as no mods are done to that section of the dock connector, and unless the iPod is reloaded with non-stock firmware (Rockbox), I can't see why the control feature shouldn't function correctly.

 

Would greatly appreciate any comments/insight.

Edited by TorchVert - 1/31/13 at 7:12am

I don't see why the mod would affect the remote operation. Using rockbox, however, definitely would kill that functionality. Of course, I may be wrong but you are only affecting the flow of the audio path through different (better than stock) capacitors. Whatever pins/circuits operate the remote functions are untouched. 

That's my guess, at least

I haven't read through this thread but does anyone imod the 5.5 and put the black gates inside it?

Funny...I was always under the impression that the 5.5's didn't have enough space inside to fit in caps (unless the HDD is replaced with a CF or some other smaller storage.

You are correct.  Using a 1.8" hdd (like the original) doesn't allow for the caps inside the case (hence, the special LODs with caps in them to complete the mod).  Doing a CF or mSATA mod leaves plenty of room for internal caps, and the flexibility of using any dock or LOD with the unit.

Black Gates caps are probably large. But small capacitors can be put inside iPod 5.5 with 1,8" 8mm thick HDD.

http://forum.avmania.e15.cz/viewtopic.php?p=8858205#p8858205

They are probably this http://www.ebay.com/itm/251009455884 or this http://www.ebay.com/itm/251009455611 caps.

Edited by kuko61 - 2/11/13 at 3:17am

Hi,

 

this is my first post here and my english is not so good to understand all this thread replies.

So i'm asking for help and some questions regarding the DiY mod of my 5 gen iPod.

 

1) Do I need to remove capacitors and inductors? Is the final quality depends on this?

 

2) Is correct soldering my wires from the south ends of the “Z" caps to the bare circular metal pads south of the inductors/capacitors pair (the last 2 pads below L3 line)?

 

3) I've tarkan CF and I can put internal capacitors into the ipod case. Where do I solder these capacitors???

 

Thank you very much,

Michele