DSP: The finale

Let's sum up many of our thoughts into this last post on DSP and move on to something else. I am a user I am an admitted user. Yes, it does not require an intervention for me to own up to my addiction to DSP. When we built my home theater we applied as much room treatment as we could tolerate from an aesthetic standpoint: three absorptive wall panels, carpet and furniture. Any further improvements would be handled with DSP through a microphone and setup within the Marantz receiver. And there were several reasons for this. In a home theater setup speakers are placed in specific areas for surround sound: left, right, center, sides, rears, ceiling. They are nearly always in-wall or at least on-wall, offering no chance to move them. Secondly, seating position is more a function of viewing distance, not where it sounds the best. Lastly, DSP is built into every decent surround processor on the market–nothing more is required, it's part and parcel of the chain–and all modern surround processors have no analog requirements–they are digital to begin with. With all these considerations, DSP in my home theater environment makes good sense and the audio sounds better with it rather than without it. I too use tone controls DSP isn't the only way we make gross adjustments to compensate for the room. In my main audio system I have adjustable subwoofers, tweeter and midrange volume controls that I tweak. Many of you know my feelings on subwoofers. They are a necessity for full reproduction of music. Whether built in or separate, a pair of woofers dedicated to the frequencies below 100Hz are a must. Period, end of story. If you don't have one, you don't have low bass. I know, I know, I am going to catch flack for that statement, but it's true. And most reasonable subwoofers have controls that help integrate them into the room. (hint: don't believe speaker manufacturer's claims of low frequency response. If a passive speakers looks like it couldn't have low bass, assume that it doesn't) I do not appreciate overkill Well, as a vegetarian I don't appreciate killing anything… but more to the point, adding a DSP to your signal chain to fix the way your system interacts with the room is a little like taking diet pills to lose weight when you are better off simply eating less. In other words, don't take a sledgehammer to fix a problem that is easily fixed otherwise. I have rarely seen a case where I could not affect the tonality, imaging and performance of a stereo system by getting the placement correct, adding a simple diffuser, or exchanging poor performing products with better ones. Get the basics of the system and the room right first, resort to a sledgehammer only when all else fails–and even then you're better off because you'll need less of the hammer's blow. DSP or ASP are great for active loudspeakers There's perhaps no better means of making a complete loudspeaker system than a well designed active one. Matching perfect amplification and crossovers to drivers and cabinets allows the greatest freedom to designers to get it right. Downside: people aren't overly interested in buying them, each channel must be plugged into the wall, they are not simple to feed from a source. Nothing is free There is no brass ring to grab. Nothing is free, everything has baggage associated with it. There are no miracle anythings and while we may be delighted and enchanted with gizmos and whiz bang technology (I am guilty as sin) it is instructive to remember there's a cost/benefit to be weighed. Occam's razor "Among competing hypotheses, the one with the fewest assumptions should be selected." If you look at most high end stereo systems you find that it is the choice of equipment, the placement of the speakers, and the skill of the installer that makes or breaks performance. In the hands of a skilled setup person few reasonably thought out collections of kit can't be manipulated to sound terrific. Start with the basic first, head to fancy signal processing and hammer-like solutions last.