[Lil' Knight]

Is there any significant sonic difference between the 22uf and 47uf in gen5?
Which one do RWA and ALO use in their iMod?
And, has anyone tried bypass the 22uf with 0.1uf NX-hiQ?

 

[joneeboi]

Quote:

Originally Posted by dumbears /img/forum/go_quote.gif I was thinking of swapping out the 100uF decoupling caps in my iPod Photo 60G with 220uF. When I opened out the case, I think it may be possible to go for BG NX 220uF, though I heard sb commented it's already much improvement in using BG NX 100uF.

I tried placing my 47uF caps like RWA did up near the HP jack, but they ended up getting crushed. Maybe if you have a 60GB back panel, it might be easier than in my 20GB. If you do, let us know how it goes, and take some pics along the way.

Quote:

Originally Posted by Lil' Knight /img/forum/go_quote.gif Is there any significant sonic difference between the 22uf and 47uf in gen5? Which one do RWA and ALO use in their iMod? And, has anyone tried bypass the 22uf with 0.1uf NX-hiQ?

From the little I do understand about BGs, bypassing should only be with NXs that have 10% the capacitance of the original cap. Over in the Millett MAX thread, TomB reported that Sprague Vitamin Qs bypassed the BG NXs to good effect, and the Millett Hybrid MAX Boutique page (Can't Miss Build #1) will reflect that recommendation. I didn't hear much of a difference bypassing 22uF with my 1.0uF VitQs, but I did hear quite a bit of difference replacing the BGs with the Spragues. Nevertheless, the latter pair was far too large for practical use (for me anyway), as I prefer keeping the caps inside the iPod. This situation will have to change as I patiently wait for my iPod prying tools to come in so that I can diyMod my iPod touch. Then I will probably have to send the caps into the docking station. Maybe I didn't give the caps a good enough chance, but I don't foresee bypassing taking place in any of my diyMods soon.

Where are you planning on fitting those bypass caps? Seems like it'd be quite a tight fit in the LOD.

 

[wgr73]

Quote:

Originally Posted by joneeboi /img/forum/go_quote.gif ... so that I can diyMod my iPod touch.

I would not recommend this to anyone!! Lol, Jon is a master though, so it's ok

. This is risky business on such an expensive piece of hardware! I hope the best Jon!

 

[joneeboi]

Thanks for that vote of confidence, wgr. I won't let you down.

 

[wgr73]

cool!

 

[DrizzitT]

So I just did the DIYMod (caps are damn small...), and I haven't broken anything, but I do have a problem

Apparently there is a DC offset of ~ 50 mV between each channel. One channel is offset by ~1 mV (probably ok), but my other channel is offset ~70 mV. Any ideas what could be the problem? This was measured already running through the dock w/ capacitors...


Edit: Offset magically disappeared.... I can hear a slight imbalance in headphones, but DIMM is showing onle ~12 mV offset between channels... One channel is 10 mv above ground, other channel is 2 mv below..

 

[FallenAngel]

Quote:

Originally Posted by DrizzitT /img/forum/go_quote.gif So I just did the DIYMod (caps are damn small...), and I haven't broken anything, but I do have a problem Apparently there is a DC offset of ~ 50 mV between each channel. One channel is offset by ~1 mV (probably ok), but my other channel is offset ~70 mV. Any ideas what could be the problem? This was measured already running through the dock w/ capacitors... Edit: Offset magically disappeared.... I can hear a slight imbalance in headphones, but DIMM is showing onle ~12 mV offset between channels... One channel is 10 mv above ground, other channel is 2 mv below..

After a pair of caps, there should be absolutely no DC, that's the idea

If it reads anything other than 0V, you've got something amiss.

 

[Lil' Knight]

Just opened my Video and taken a look.
It's really tiny

I've looked back and wonder if I have to remove these 2 caps:

 

[FS2]

That black wire seems to have an exposed core that's awfully close to a cap. Hope that's held down real well.

Quote:

Originally Posted by ruZZ.il /img/forum/go_quote.gif I believe there is some space in the mini up around the headphone jack area to stuff 2x47uf 6.3v BG NX caps.. a little round about for the signal cable, but I doubt it'll effect anything. I should be getting some cf cards soon so I'll be able to play again.. when I get some time too.. hmpf. been a bit busy, but it should even out soon

I checked mine (while sticking in my 16 GB Adata card

) and that's a really small space. If the existing caps are indeed 100 uF and I do a replacement, that wouldn't be an improvement, would it? On the other hand, if I add caps, without removing the existing ones... but the lack of space is then even more of a problem. Of course, the other option is to pull the same caps of a dead mini board and stack them in.

On that note, I was listening to my 4th gen iPod and a 2nd gen mini (both stock audio path). I can't tell the difference between the two. Now either it's my choice in music, my PX100 headphones, or just me. But does anyone actually hear a difference between them?

BTW, joneeboi, I checked the chips in the mini's I've seen and I can confirm that the 1st gen uses a WM8731 while the 2nd gen uses a WM8711. (You might want to update your first post

) But I don't think there's much difference between the two.

 

[joneeboi]

Quote:

Originally Posted by Lil' Knight /img/forum/go_quote.gif Just opened my Video and taken a look. It's really tiny I've looked back and wonder if I have to remove these 2 caps:

You could and should. Just make sure you don't nick anything else on the way out.

Quote:

Originally Posted by FS2 /img/forum/go_quote.gif On that note, I was listening to my 4th gen iPod and a 2nd gen mini (both stock audio path). I can't tell the difference between the two. Now either it's my choice in music, my PX100 headphones, or just me. But does anyone actually hear a difference between them?

It could be your equipment. The headphone out for my 3G and 4G were pretty similar, but amping them makes a pretty big difference. I can definitely hear a difference between the touch 1G and diyMod 4G. I'm amping with either Mini^3, PIMETA, or MAX on my tricked out SR60s. I wouldn't expect to hear much of a difference between HP jacks, but maybe you need to try my method of sound comparison. Listen to one setup for a long time, say a week or two, so that your mind unconsciously picks up on the nuances that you can't consciously notice. Once your mind gets settled in, make the switch and see if your ears "perk up" to take notice. Eventually, it becomes just a natural occurrence as you pick whichever player you like better and stick with it for a while. Some day you'll pick up the other player and give it a go, and your eyes will widen and fingers sweaten. Happened the first time I listened to the touch coming from the 4G and when coming from my previously owned ZVM to my dad's 5G or my touch 1G to my brother's nano 3G. Give it a shot, then hesitantly make your conclusion.

Quote:

Originally Posted by FS2 /img/forum/go_quote.gif BTW, joneeboi, I checked the chips in the mini's I've seen and I can confirm that the 1st gen uses a WM8731 while the 2nd gen uses a WM8711. (You might want to update your first post ) But I don't think there's much difference between the two.

Updated.

 

[FS2]

Thanks for that suggestion. I'll give it a try.

 

[vikingboy]

found this which is interesting, review of 21 different types of capicitor.

http://www.vhaudio.com/21capacitorshootout.pdf

Linked from VHaudio who sells very high qulaity DIY cable stuff cheaply. No connection over than happy customer in the past.

 

[joneeboi]

Thanks for that link, vikingboy. I remember skimming through that page some time ago because it was posted in the Millett MAX thread. I also remember some people (couldn't tell you who) cautioning readers about the reviewer's report on Jupiter beeswax capacitors being unreasonably critical and biased. For this kind of review, I'd prefer pointing out dsavitsk's Notes on Output Coupling Capacitors, as he is an active member here and at Headwize, contributing such projects as the Less-pressivo, the HPDAC (1, 2, 3), the Grado-RA-1-turned-Alien-DAC-slash-PIMETA, and many, many more; IOW, he knows his stuff. He links the VHaudio review, but I just want to remind the reader to keep dsavitsk in mind when researching capacitors.

Thanks again, vikingboy. I'll add both links to the OP.

 

[vikingboy]

Nice to be able to contribute something back to the forum that has taught me so much. Even if that something is a link to someone elses work!

Ive got my 2nd gen mini modded with the 32GB Adata card, have a new shiny soldering oron and tips on order and will be doing the DIYmod and making some LOD cables next week. Ive got the obligatory BGs and will be experimenting with some bigger Vcap, Auricaps and Mundorfs. Really appreciate the dsavitski reference and look forward to drawing my own conclusions.

Ill be sure to post pics and reviews of the caps once run in too.



fingers crossed I dont screw the mini doing the DIYmod.

 

[joneeboi]

That's what this thread is for.

It seems that even though Apple got rid of the mini, it still remains a popular player. It was still flying off the shelves when Apple replaced it with the nano, so it's no surprise that people are still messing around with them. I have two non-head-fier friends with iPods in some of my Electrical classes and they both have their original minis.

It seems it also lends itself to diyModding quite easily with such a short signal path from the coupling cap to the dock. The caps are even placed such that they can be easily removed without toasting most nearby circuit elements. I'm taken aback by the mini's comeback into head-fidom since it was discovered quite a long time ago that they could take accept CF cards. (Enjoy the mini 2G, ruZZ.il.

)

Thanks for sharing, vikingboy. I eagerly await to add you to the "gallery."