To connect your iPhone, iPad or iPod to your home stereo you just need a 3.5mm to RCA cable like this cable above. The two RCA connectors plug into the back of your stereo and the 3.5mm plugs into the headphone jack of your iPhone. Pretty much every stereo available has RCA inputs as the standard inputs on the back. If you want the best possible audio quality, then an Apple iPod dock will make it sound even better, but we’ll get to that in a moment.
Buying a cable
The first thing that you will need is a cable. One end of the cable has a 3.5 mm headphone jack. This looks exactly like the socket on the end of your Apple headphones. It’s also nicknamed an ‘aux’ cable. The other end of the cable has 2 RCA connectors. These will plug straight into your stereo. The cable looks like this:
These cables start as cheaply as 1c (e.g. here) but I’d steer away from one like that which uses cheap cable. Pretty much anyone can tell the difference in the sound on one of these cheap cables even if you don’t know much about music at all. The difference between a mid-range cable and a high end cable is less noticeable unless you have a good ear and a good stereo. I use one like this which costs about $25, but you can buy one somewhere in the middle range for around $10 like this or this and it should be fine. I find Belkin to be pretty reliable. Steer away from anything on ebay that looks like this:
I’ve written an article about finding the best cable here.
How to plug the cable in
You can plug the 3.5mm straight into your iPod headphone jack, and the other end will plug into your stereo. This is not the best solution (read on further down in this article) but it works.
For best results set your iPhone volume to about half. If it’s too quiet you may get some noise and hiss. If it’s too loud you may get some distortion.
When plugging into the back of the Stereo Amplifier, the normal input to use would be the AUX-IN, but you can use almost whatever input you want: CD-INPUT, TAPE-IN, TV-IN, DVD-IN or the AUX-IN.
Do not use the PHONO-IN as it is designed specifically for a record player and won’t sound as good.
Next Page: iPod Dock and wireless Airplay…
Buying an iPod Dock
When you plug your iPhone directly into your stereo as I’ve described above there will be a very slight loss of audio quality. This is because the headphone jack is designed to power headphones, not be plugged into a stereo. (You can read about the technical differences here.) For most people this will probably not be noticeable, so unless you have a really good stereo with a nice set of speakers the straight cable will work fine.
If however you are after the best possible audio quality into your stereo, equivalent to or better than a CD player, then can buy a “dock” for your iPhone.
Apple sell iPod and iPhone docks for the new lightning connecto here, but for older iPods that don’t have a lightning connector, Apple don’t sell this product any more. Even their own support article here (dated Feb ’15) now tells you to plug the iPod straight into your home stereo from the headphone jack. (This will work, but it is definitely an inferior sound quality to the dock.)
So, for the best sound quality, you need to track down a 2nd hand iPod or iPhone dock that will suit your iPhone or iPod.
In ebay you will need to search for something like this:
“Apple Universal Dock genuine”
“Apple Dock MA045”
“Apple Dock MC746LL”
“Apple Dock A1371”
Plugging in the iPod dock
This is an Apple iPod dock. It has a ‘line out’ output on the back. (The jack on the left in the above picture). Using a line level out will give you the best possible sound quality, better than just using the headphone socket. This is because the line out has been designed to put out a signal that is perfectly matched to a home stereo that has a ‘line in’.
The headphone output on the iPod is not a true ‘line out’, it is a headphone level. This is different. A headphone output is expecting a pair of headphones and while it will still work fine, you may lose some high-end or low end or clarity using it as a line out instead of a headphone out. The dock gives you a proper ‘line out’ which will be the exact voltage and impedance to match the ‘line in’ on your stereo. This is important for the best sound quality.
Use exactly the same cable that I talked about above. The headphone jack and plugs into the ‘line out’ from the dock, and the RCA connectors plug into the back of your stereo.
There are other advantages to the dock. The first one is obviously the better audio quality. But you can also leave the audio lead and charger cable plugged into the dock permanently, so that whenever your phone or iPod is plugged into the dock it will be charging at the same time that it is playing. The Apple iPod dock also has an infrared receiver on the front which will allow you to control your iPod via any Apple remote control! so you can play and pause your iPod using the Apple remote control.
Note that the newest iPhone docks (iPhone 6 and newer) do not have a ‘line out.’ The first generation of lightning dock did have a ‘line out’.
The first generation of lightning dock with a true ‘line out’.
The newer iPhone dock with output is marked as a headphones not ‘line out’.
There is a lot of confusion on the Apple support sites as to whether this socket marked headphones is actually a true high-quality ‘line out’ or whether it is just the same as what a headphone socket would output.
Here is one of the comments on the apple support site:
“Apple Documentation says that it has both Headphone & Line Level output BUT I am unable to achieve this. Apple support could not help find out how to accomplish this and simply stated that the documentation “must be incorrect.”
So if you wish to have true Line Level Output like the previous 5s dock, DO NOT BUY THIS PRODUCT until Apple confirms otherwise, or at least explains how to use this product.”
It sounds like if you have a new lighting iPhone you may be just as well off buying the Apple lightning to headphone connector rather than the dock. I have not been able to confirm whether the new iPhone dock is a true line out or not.
Wireless Airplay – no connector!
If you are buying a new stereo, Pioneer and others are now including AIRPLAY into some of their amplifiers. The amplifiers have a Wi-Fi receiver built in which means you can play from your iOS device over your Wi-Fi (Airport) network directly to your Stereo with no loss of quality. You don’t need to connect any cables. This article has more information about how to connect your iPod or phone wirelessly.