Lately if you frequent online car audio forums you will notice a few things get mentioned a lot more often than others. And for good reason! DSP - Digital Sound Processor, is one of them. What the heck is that, you ask? A digital sound processor is an electronic way to control the sound in your audio system. Usually a DSP capable device will have: - an Equalizer where you can adjust volume of specific frequencie bands - Crossovers grant ability to adjust the frequencies that each speaker is allowed to play
- Time Alignment a way to delay the sound from each speaker
- Channel Level helps to adjust the level of volume from each channel
Some nicer DSP will also have more features. Nicer units often come with automatic EQ capabilities which use a microphone to help you tune as well, Others have the ability to EQ more bands individually and some even come with way more output channels than others. The crossover menus on nicer units will also feature many more options including bandpass and variable slopes. I have even used a mosconi DSP that allowed me to add more than one crossover on a channel and had several different types of crossovers.
Now a lot of headunits that are on the higher end side of things also have simpler version of DSP built into them. Pioneer touchscreens, and Kenwood touchscreens. The nicer unit will often have crossovers that are super easy to adjust with the touch screen, an eq that is for all the channels together, channel level control, and time correction which is super easy to setup on the touchscreen. Honestly the only drawbacks to having DSP built into your headunit only is the EQ is not adjustable for every channel individually and the preouts are usually limited at only 6 channels.
If you are trying to add a 3 way separate front speakers and only have the DSP built into your headunit that is no problem because you can still find other ways to crossover the tweeters, like a capacitor for example (passive crossover vs active). Sometimes you can get creative, or old school with the design and install to make it sound good without a true DSP.
If you have the knowledge of how to tune these things, the patience, and the money to afford all the extra amps and channels then a DSP can be an amazing investment. I usually describe to my girlfriend tuning an amp is like learning how to drive a car. Tuning a DSP is like learning how to drive a race car. You better already know how a clutch works or you will have a very steep learning curve. I will be happy to help give my advice if you get into a spot with your DSP that you cannot figure out. I will warn you ahead of time just be patient setting it up and plan on doing a LOT of listening. several days worth of listening. Rome wasn't built in a day you know. Feel free to join Facebook.com/groups/caraudioinstall if you need any help with your DSP. I sponsor that group and will be happy to help you out.