myth on soldering!

I solder all connections under the dash (security/remote start), as well as most fm modulation connections.  Depending on what gauge the factory wiring is and what kind of mood I'm in, sometimes when hardwiring a deck I'll use butt connectors, and other times I'll solder.

We use harnesses and crimp caps (using ONLY Klein-style crimpers) whenever possible for deck installs.  It's just so much faster than soldering.  Usually for speaker and amp wiring I'll use crimp-on spades and ring terminals.

Also another thing to remember is that inhaling solder fumes is not exactly the best thing for your health.  And really the only way to avoid inhalation when you're under a dash soldering wires is to stick a fan right next to your head to blow the solder smoke away from you, but we don't really have one of those just lying around (can you say OSHA violations????)  Most of our installers smoke so it's kinda pointless for me to argue this point, but still it's one reason why I sometimes just don't feel like soldering.

You will never get a better connection than you will with solder. I have always soldered my connections but just like Blazermedic says, it's very time consuming especially if you don't do it right the first time. I use shrink tubing as well to cover each wire so I have no possibility of shorting. I then wrap the wires with 3M electrical tape.

ScotchLocks, T-Taps and Butt connectors all have the possibility of failure. far more than any solder joint I've made...

Like pretty much all of you have said, soldering is time consuming. But, answer this... Why is there never enough time to do it right, but always enough time to do it over? Anyways, every good installer has their methods to make a secure conductive connection, and by now they have perfected their method. For example, whenever I use electrical tape, I throw cable ties over it so that varying temperatures can't promote unraveling. If I use crimp caps, I cable tie the wires together just below the crimp cap to keep the wires as one. If I use butt connectors, I use NON-insulated and shrink tubing. However you do it, keep in mind that you will most likely be the one fixing it if it breaks.

On the frequency loss note... sorry guys, but that is total BS in the audio world. First of all, if solder had that much degrading properties, it would not be used on every single connection inside of your computer, especially the processors. Second, the only frequency loss solder would ever encounter wouldn't actually be frequency loss, especially not in the audible range, it would just be that you've exceeded the conductive capabilities of wire. For example, microwaves and lightwaves not soundwaves.

oh, and third, on the frequency note.... aren't the leads on the actual speaker soldered to the voice coil? =)