http://www.pioneerelectronics.com/pn...etailComponent http://www.pioneerelectronics.com/pn...etailComponent I am debating between these 2 cd players for my car. The only difference between the DEH-P77DH and the DEH-P47DH I see, besides the alarm and remote, which I do not need, is that the DEH-P77DH has 3 pair (Front, Rear, Sub/Non-Fading) RCA preouts, while the DEH-P47DH has 1 pair (Rear) RCA preouts. The DEH-P77DH also has Hi-Volt (4V), 100 Ohm Preout Voltage & Impedance, while the DEH-P47DH has 2V, 100 Ohm Preout Voltage & Impedance. Could someone please explain just exactly what that means? What are RCA preouts and what is Preout Voltage & Impedance? What exactly do they do? Forgive my ignorance, but I've never really looked into audio equipment until now.

The pre-outs are the connections that go directly to the amp. So if you plan to run a multiple amp system, the DEH-P77DH is the way to go. An example could be 1 amp for the front components, 1 amp for the rear components, and 1 amp for the sub. Of course, you dont need to use that many amps, it would work with 1 or 2 amps. Good thing is that headunit will give you more flexibility down the road if you do decide to go all out on the sounds. The higher voltage pre-out basically means the sound quality will be better since the amps will be getting a stronger signal. I'd say go with the DEH-P77DH.

I don't plan on running any external amps, just a basic setup with the mentioned aftermarket deck and some replacement speakers. So basically the RCA Preouts just connect to seperate amps and the Preout Voltage & Impedance just controls how good of a signal the amps recieve? In other words, if I were to stick with just replacement stock components the 2 decks would perform identically?

the signal from the RCAs to an external amp will be much cleaner than the H/U's signal. itll be less likely to distort and the such

Maybe so, but I will not be running any type of external amp or subs in the car. Basically I'm just asking if the DEH-P77DH will provide any benefits over the DEH-P47DH for my setup, which will simply be replacement speakers and HU.

Yeah if you dont plan to run any amps, and you dont think you will in the future, they would both be the same in your situation. So the DEH-P47DH would probably be the cheaper better buy for you.

I noticed both units have a 2 way crossover. What exactly does that mean. Will a 3 way or more speaker function properly with a 2 way crossover? When a company refers to a speaker as 2 way, 3 way, etc, what does that mean?

To understand crossovers and 2way/3way or whatever, think about the different ranges of sound. The easiest ranges to identify are the extremes, so you have subwoofers that produce really low bass, and then you have tweeters that produce all the high's. Each of those two different types of sound (lows vs highs) are running different frequencies. Most people divide it up into 3 ranges, lows (subs), mids (components), and highs (tweeters).

When a speaker is advertised as 2 way or 3 way, that stands for the ranges of sound that the speaker can handle. If you visually compare the two, you'll see that 3 ways usually have 3 speakers, while 2 ways have 2 speakers. So a 3 way speaker will probably be able to produce lows, mids, and high's, whereas a 2 way will probably only do lows and mids, or mids and high's. Just remember that more is not always better. The "best" setup is determined by how everything in the system matches up. So the 6x9's with the best specs will not automatically be the best choice. It would depend on what other speakers you have in the car, and how well it matches.

A crossover is a device that will split the frequencies up. So if your speaker is only designed to play low bass, the crossover can be set to only deliver low bass frequencies to that speaker. And it works the same for mids and high's.

When you build a system that is high end quality, you really need to get into the frequencies of each speaker. Each speaker should be chosen for a specific sound, and matched up with the rest of the group. I'm building my new system for the best interior sound quality I can get, not for loudness or competitions or whatever. In total I'm gonna be running 10 speakers and 4 amps, everything matched up, and only playing the frequencies that they perform the best in.

So can you match a 3 or 4 way speaker with a 2 way crossover HU?

Yeah, no problem.