DIY: How to make an iPod Line Out Dock (with photos)
by, 05-17-2011 at 12:09 PM (18647 Views)
I'm pretty new to the audio DIY stuff, but it can be a lot of fun. You'll find differing views on what benefit an LOD will do for sound quality. Basically instead of using the headphone out you're using the line out on the iPod (or other mp3 players have this also). I like the sound quality better with my headphone amp using an LOD and I have the satisfaction of building all of it (except the iPod of course). People spend hundreds of dollars on this stuff, it's cool building it yourself even if you feel like smashing all of it when you make a mistake.
This is the third one I've attempted. The first one came out okay, the second was a disaster. If you're not too familiar with electronics and DIY audio this is a good post: http://jaben.net/forums/index.php?topic=10647.0
So enough foreplay, lets get to it.
First I'll list off what I used for the LOD. We'll start with tools, I won't get too specific but if you have questions let me know.
Small flat screwdriver
Small tip needle nose
Heat gun (if you decide to use heatshrink)
Helping Hands soldering station
Mogami Quad Cable
Dock Connector (black)
Pailiccs 3.5 Connector
68k ohm resistor (this is only needed if you're building it for an iPod touch/phone 3rd gen and above)
Techflex braided sheathing
Because I've had issues with the pins getting pulled out of the dock connector, I start with the mini jack. Unscrew the cover if it's not already off and fire up your soldering iron. First, strip the shielding off of the cable and strip each individual cable just enough to get some solder on it. I strip maybe 1/4 of an inch then strip the wires individually. We'll have to keep track of which cable is our ground, left and right. Since we have 4 cables, we can eliminate one of them. I chose to eliminate blue.
In my example:
Red = left channel
Clear = right channel
Black = ground
I do not recommend using the Pailiccs connector if you're starting out. It's a bitch to solder and a little confusing at first. Solder the connectors together and be sure none of the solder is touching and it's nice and neat. The Helping Hands station is a HUGE help doing this stuff, but if you attach your 3.5 jack to it, be sure to put some black tape to protect the connector. (Sorry for the picture quality, lighting near my desk is funky at night)
It sounds silly, but before we start on the other end of the cable, be sure to put the cover to your mini connector on the wire. Otherwise we'll have two sides soldered but the cover missing! I've done it and it's not fun. So check after each step to make sure you aren't missing anything. Missing something and going back could be a pain in the ass.
Alright now that we have this side done, we have to get the dock connector ready. It has 30 pins and we won't use all of them. We only need a few:
1, 2 = ground
3 = right
4 = left
11, 15 and 21 = our resistor will go here
As you look at the dock connector, it's easy to get confused.
So many pins, and they are really small. We have to be careful. We will be pulling all of the pins out except for the ones listed above. So how do you know which ones are the right ones? It's actually not bad. If you're looking at the connector with the "slit" side up (you can see the little slit in the picture) then the top row is odd numbers, the bottom is even. Something like this
Top (slit side up)
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
The good news is we only have to keep one even number. So on the bottom row, take your small needle nose and bend that pin back. Then count off the odd number pins and bend each one back. I've found it's easier to bend them back and pull out the straight pins because it's easy to miscount with the pins being so small. So unless you're a Kiebler Elf, I strongly suggest trying it this way. If you pull out the wrong pin, don't worry! Hold onto your pins and you can put them back into place if needed. It's not easy but it's doable.
Below is the connector with the pins we need and the ones that were pulled out.
Next we'll solder our resistor to the connector. If we don't have a resistor on a 3rd gen iPod touch/phone we'll get an error message when we plug in our LOD. If it's worth doing its worth doing right. Take pins 11 and 15 and bend them so they touch. Trim the resistor down so it's not so big, we want it to fit inside the connector. Now solder one end of the resistor to the combined 11/15 pins and the other end to 21.
Get your techflex and measure it off (or eyeball it) and cut it to the size of your cable. I like my cables to be a little longer just to have slack, but you can go as small as 4 inches or so. Slide it in before you start soldering the wire to the connector, again it's doable but it's easy doing it before. On there? Good, lets start soldering our cable to the remaining pins on the connector.
The pins on the connector will line up with our wires from the cable. If you haven't already, strip the other end of the cable. Now lets line it up, pay close attention it's easy to solder the wrong pin.
Combine 1 and 2 on the dock connector (ground) = soldered to black cable
Pin 3 (right channel) = soldered to clear cable
Pin 4 (left channel) = soldered to red cable
Now before we use any heatshrink, start closing our clamps ect. Lets test it. Plug the connector into your ipod/ipod touch/phone and you should not get any error messages. If you do, something is wrong. Go back and check your connections. The other end goes in your amp and of course you need headphones/speakers.
Check both channels, right and left. Check volume and make sure you aren't getting a hiss or any distortion. Sound good? Awesome, lets finish up.
I'll be honest, the iPod connector gave me the most trouble out of everything. Maybe my fingers are too big, or maybe I'm just a dumbass. Some people like to use hot glue on it, but I don't like gluing anything like this unless you have to.
Close up the connector and also slide your the connector for your plug up and screw it in. Now if you have heatshrink on the wire to secure it, you'll want to apply the heat before you do these steps. Too much heat can melt the connector if you're not careful. I was lucky and my techflex was just long enough I didn't need heatshrink. Some people don't like to use techflex, some do. You can also choose to use a single stranded wire and braid it yourself instead of buying insulated. See this example.
So lets check out our cable now that it's all secure and we verified it is functional.
And lets try it out!
You just built your very own DIY iPod LOD cable! Now you can be the envy of all the audio geeks in your neighborhood. I'm open to questions, suggestions and of course comments are always appreciated.
I'll post my next project soon, probably a mini to mini cable.