joneeboi
Headphoneus Supremus
- Joined
- Jul 7, 2006
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It's in the datasheet for the 5G. I don't exactly remember what VMID is, and this computer isn't loading the datasheet so that I can tell you. Yeah, it's in the datasheet.
Originally Posted by Hayduke /img/forum/go_quote.gif I don't understand. What is VMID? So you are saying the line out on pins 3 and 4 of the dock connector are muted? |
Originally Posted by no_eye_dear /img/forum/go_quote.gif No, I'm talking about the DAC chip. OUT3 and OUT4 are alternative outputs that can use the same mixers as the HP out but they can run at higher voltage like the line out. They can even run higher @ over 2V if the 'boost' is enabled. Apple have muted these outputs so you can't use them in favour of allowing a DC coupled output on the HP. Look at my earlier post ref the application note, or on the spec sheet, for more information on DC coupled HP out. Basically it allows you to use the HP out without capacitors by raising the ground to the same voltage potential as the outputs. You connect the ground wire to the VMID pin instead of a common ground connection. *****Not recommended if you do not understand the grounding requirements of your amp***** TTFN |
Originally Posted by joneeboi /img/forum/go_quote.gif How flattering that you'd sign up just to post in this thread. Welcome to head-fi, sorry about your wallet. Headphone functionality If you do it the way specified on the front page, then you should retain the headphone jack signal. Capacitor SQ That ultimately comes down to the overall sound of your rig. What headphones (/amp/cables/other accessories) are you using? I love my diyMod 4G with Black Gate NX Hi-Q 47uF 6.3V to PIMETA with AD8620/AD8610 + TREAD through my rescreened Grado Labs SR60s with Canare Star Quad recable, Grado Labs Jumbo Pads with glue mod and sticky tack driver mod. I was told at a meet that my headphones sounded better than another member's GS1Ks, but again, it all completely comes down to your sound preference and rig. Short answer goes something like "Find the sound you like on your rig. I like the BG NX Hi-Q 47uF 6.3V in my system." Internal Capacitor It depends on what caps you want to use and what other mods you've done to your iPod. gueri_fr proved to us that internal caps was a possible option when you did the CF mod. So far as I know, others have not been able to reproduce the internal caps, but we never say 'die' in DIY, do we? Docking Speakers They won't work unless there is some method of keeping the DC from getting to the speaker. It boils down to each speaker docking station, so one can't really say for sure. Generally, I would say they wouldn't have that protection because there isn't a threat of DC being in the signal with the stock iPods, but again, you can never really say for sure. Why don't you open your speaker dock and find out? |
Originally Posted by joneeboi /img/forum/go_quote.gif You could certainly install a switch. If you want to keep the line out to pins 3 and 4, I imagine you would have to incorporate the switch into the iPod itself. Another way would be to put the switch into the cable or after the cable and wire the line out straight to an unused dock pin. You'd need at least a DPDT, or double-pole-double-throw, switch, so space may become a factor depending on which one you get. That might be nice for comparisons. |
Originally Posted by mbarry /img/forum/go_quote.gif So if I were to wire it in parallel to the original, both would work fine right? Then I would wire the parallel lines to an unused part of the dock, and make a 30 pin connector with line out that corresponds to the part of the dock that I used earlier, right? Thanks again. |
Originally Posted by joneeboi /img/forum/go_quote.gif ...Should I be thinking out loud like this? |