Audiophile Review Editor Steven Stone once told me that $2000.00 worth of room treatments could possibly have as much sonic effect as an expensive DAC I was, at the time, considering buying. Given his pedigree in high performance audio I had no reason to doubt him. I carefully considered his advice, naturally ignored him and went ahead with the DAC I was all abuzz over. Just under a year later, I finally got around to room treatments and quickly realized that he was, of course, absolutely correct. Room treatments do make a profound difference when properly executed. And while I was technically both right and wrong in my decision to purchase the DAC, it was a very profound upgrade - the combination of the new component and the room treatments took the sonics to a place that one or the other on their own would not have reached. Despite the total cost, it was a best of both worlds exercise.
Room treatments are not the only way to improve sonics in a listening space. Yes, source components and amplification upgrades typically yield a better sound, and while each cable upgrade I've made was noticeably better than before, there is still another option. To a large extent, that option boils down to one key ingredient - math.
Digital Signal Processing, or DSP, is a widely used room correction methodology that examines the room and mathematically makes signal changes to correct deficiencies. One of the most helpful things about DSP is that the correction process is specific to the individual room and not a one size fits all - which would obviously not work very well. While DSP is widely accepted as a proven approach, does it completely and totally eliminate room treatments?
Possibly, one of the first consumer oriented attempts at DSP was the slider type graphic equalizer controls found on many 70's era equipment. One could digitally change the landscape of the music even if the actual result was mostly minimal.
While a number of companies were pioneers in DSP technology, two companies - SigTech and TacT are usually credited for introducing the software that birthed modern room correction. Many companies today use a licensed version of the software that is based on the creation of what those companies introduced.
While different systems vary, the basic use is mostly the same. Ideally, a flat frequency response is the goal. A microphone is placed in the room, pink noise is played, and the software will look for areas that do not meet a predetermined frequency response. Once detected, the software will digitally equalize the signal to achieve as close to a flat frequency response as the room and the software will allow. The microphone is typically placed in multiple, pre-planned spots in the room until the whole room has been evaluated. Again ideally, the end result is a vast improvement in the quality of musical reproduction.
Room treatments, on the other hand, seek to improve sonics on a more subjective, listening based methodology. There are room treatments that absorb - typically used for low frequency sounds like bass, reflectors that bounce the frequency along in the room and ones that do a combination of both. Knowing your room and understanding exactly what your problems are go a long way in creating a game plan for room correction. How well a listening room is treated with the various panels available is dependent upon the listener's knowledge on exactly how room treatments work and where the specific problems lie. Make no mistake, a well-executed system of room treatments will take the sonic quality to a much higher level than a room with no treatments. Remember the old, time worn adage - play the system, hear the room.
Obviously, using both is the ideal solution. There are attributes found in both that legitimize a joint solution to room correction. But very often, both systems cannot be utilized. There are any number of reasons that multiple acoustical panels glued or mechanically adhered to walls in a given listening space will not be wanted. Many married audiophiles will understand that. And perhaps the cost of DSP is beyond the reach of others. Of course, there will be a certain faction of audiophiles that basically find the whole concept of room treatments basically pointless - despite either an acceptance of physical panels or the ability to afford DSP. It really depends on one's level of interest and acceptable levels of musical quality.
Making a choice between the two has other issues to consider. Many audiophiles consider themselves as mostly "purists" and the use of digital correction is anathema to a pure signal. While it might be argued that, to a point, panels do the same thing, many will disagree, noting that the reproduced signal is not changed before it leaves the speaker. And again, some won't even care.
Ever heard the saying about opinions? Everyone has one right? So is an answer to this question even possible? There are more factors to consider than space in this article allows but suffice it to say that an easy answer is the same one typically found in every area of high performance audio. Which is best, a tube amp or solid state? Planar speakers or dynamic? Analog or digital? Answering all of these questions is really very simple. It is whatever the user prefers. And while room treatments will most likely be the most profound if a combination of both panels and DSP are utilized, using one or the other is certainly acceptable as well. In fact, for my room, I have taken more of a "purist" approach and am currently only using panels in the room. Am I wrong for not using DSP?