EQ, DSP, & You: A Cautionary Tale

Written by Jim Smith

Some of this info was presented in the Copper Subwoofery series. But it was buried within lots of set-up details, and I have felt that it needs to be addressed on its own.

From my experience evaluating & voicing systems, I have three main concerns with EQ and DSP:

1 – It’s not a panacea.  Some people think that if they get the response relatively flat, or “fix” time arrival and such, that is all it takes.  If you wish to use these programs (as I have), don’t even think about it until you have first done all of the basic set-up.  I have referred to this as the organic process rather than the electronic.

2 – Sadly, I’ve heard all too many systems that sounded technically correct, but were utterly boring musically because the owner or system tuner felt that once the measurement goals were achieved, they were done.  Not so!

So here’s a story that is related to the concept, at least in the area of execution. Some of you may remember the San Francisco Stereophile Home Entertainment Show in 2003.  If so, you may recall the extraordinary and never-again-equaled response that happened in our (Avantgarde-USA, BAT, Running Springs, etc.) demo room.

At this show, we went on to receive a level of universal acclaim that – honestly speaking – I didn’t expect. Two well-known reviewers (Robert Harley of TAS and Srajan Ebaen of 6moons.com) commented in their publications about this acclaim. They were amazed to see the audience stand up and applaud (!) at the end of each demo session, something that they had never before seen. More about the audio press coverage later…

As always at the shows where we exhibited, I voiced that system.  After several hours of work voicing the system to the room, there remained a few less-than-pleasant peaks in the boundary-dependent-region (below 300 Hz).  Expecting some difficulties with the room, I had brought my Rives PARC (Parametric Adaptive Room Compensation), which is designed to solely address that region.

When I mentioned to Rives Audio owner-and-friend Richard Rives Bird that I was bringing it to the show, he offered to tweak it with his computer program. True to his word, when I let him know I wanted him to drop by, he was nice enough to come over and run the program.

Richard had a ton of work to do throughout the show. He didn’t cut short his time with us, but he based his adjustments on near-perfect measurements. Ten minutes later, satisfied with the results, he went on to other projects waiting at the show.

I should mention that we were only using the PARC in the line from the BAT preamp to the amps driving the BASSHORNS.  The amps driving the TRIOS were direct from the preamp.

There was no question that the bass response was very flat now.  Technically, it was superb.  However, listening for a while after Richard left, I began to feel that the system was missing musical involvement.  The emotional hook was just not there. My response to the music from this measurably flat system was similar to its measurements – flat!

So I spent several more hours building on what Richard had done (LOL – Richard might have had a different description). I didn’t change the frequency of the three cuts he introduced, but did slightly adjust their “q” (width) and the level of their amplitude.

When I was through, I was feeling good about the sound – the music was engaging at all levels and with all genres. I privately wondered if the subsequent measurements would have been as precise.  My guess was — probably not.

Here’s the cool thing – We got standing applause at the end of almost every demo for three days – an almost-unheard-of response to a show demo!  IMO – listeners weren’t responding to the technical aspects of the sound, they were releasing emotions stimulated by the musical experience.

FWIW – I have never before (or since) seen such response from show attendees. It was unique in my long experience in the industry.

Twelve years later (!), Robert Harley again wrote of this phenomenon, in a recent issue of TAS: “The same system at a San Francisco show elicited a standing ovation with wild applause at the conclusion of Pink Floyd’s The Wall—the only instance of such a reaction to a show demo in memory.” —


The fact is, that if I had simply settled for technically excellent sound, we would still have had a good show (as exhibitors commonly think of such). As it turned out, for the next three days, we had lines of expectant listeners down the hall and around the corner, waiting to hear our demo, because (IMO) it was the musical impact that brought the listeners to their feet with applause.

3 – Unfortunately, I think it is likely to be too easy for an installer of digital room correction systems to mainly rely on the measurements. A technician onsite MAY have the requisite blend of science and art skills to do it, but not if he thinks the measurements are the cure. And even if he doesn’t, can he make the system come alive in a musically compelling manner?

And indeed there are some systems today that offer remote tuning. Some even offer automated adjustments. But who determines how the system speaks to you, in your room? Does the person – far away in an office – who suggested the changes in the EQ/DSP come out to hear the results and suggest adjustments? Someone – installer or end-user – needs to do it!

Three final observations:

1 – EQ/room correction cannot replace getting the system/room basics right before running the program. In fact, it makes what I call “Playing the Room” even more important than ever.  If the room correction program is as good as many of us are being told, completing the system with room correction – after building on a solid voicing foundation – could yield incredible long-term benefits.

2 – Even though the outcome may measure text-book-precise, I’ve found that a computer read-out of the measurements may need a little on-site “interpretation” from the end user or voicing agent in order to fulfill the ultimate promise. This is even more noticeable in so-called “automated” EQ/DSP systems.

3 – If it was me, I would FIRST listen to the EQ/DSP system without any adjustments at all. That will probably be its most transparent operation. If it sounds grainy or less dynamic when used simply as a straight pass-through of the signal, not sure I would want to use it, as the adjustments will call for more computing power, likely veiling the sound even more.

Hmm… I said above – “not sure I would want to use it” However, as I think about it, I really am sure – if it affected the sound on a simple pass-through, there is NO WAY I would use it.

Bottom line – re DSP/EQ, go for it – after you have exhausted all efforts organically. Be sure to listen to the results from a musical standpoint. If the system is not immersing you in the music, if you are not moved emotionally, you’ve still got some work to do. In some cases, that may even include removing the DSP/EQ

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