The Best Upgrades

If you’re going to upgrade something, try to upgrade at the ends of your signal chain.

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The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

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This business is so “magical gear” oriented that it hurts people. I don’t know how many bankruptcies, strained relationships, failed businesses, and heartburn prescriptions have resulted from gear acquisition, but my bet is that the number is somewhere between “a lot” and “a gazillion.” Audio humans spend a ton of money, and what’s worse, there’s a tendency to spend it on the wrong things. The search for better sound is a journey that’s often undertaken through a path that leads into the deep underbrush of mythology, and that’s a recipe for getting lost.

One perennial (and expensive) mistake is pursuing upgrades to the wrong parts of the signal path. Folks get incredibly wound up about the sound quality of things like consoles, poweramps, preamps, and even cables. They thrash around, trying to figure out why things don’t sound “just so,” and run huge bills as they do. In the process, they miss opportunities to upgrade the bits that would really matter.

If we’re talking about the part of the signal chain that involves electricity, the bits that matter are at the ends.

Transduction Is Hard

Let’s start with what I’m not saying: I’m not saying that the middle of the signal chain is trivial. It isn’t. A lot of work has been done to get us to where we are now in terms of distortion and SNR. Very smart people have worked for decades to design and miniaturize the components and subassemblies that make pro-audio go. What I am saying, though, is that signal routing, combining, and gain adjustment ARE trivial when compared to signal transduction.

For instance, let’s take the INA217, an instrumentation amplifier that can be used to build microphone preamps. At around 68 dB of gain, (the base 10 logarithm of 2500, multiplied by 20), the unit maintains a bandwidth beyond the audible range. Nifty, eh?

You can buy one for less than $7. Buy in quantity, and the per-unit cost is less than half that.

Or, take a mix bus from a console. The heart of a mix bus is either electrical or mathematical summing. Addition, I mean. The basic process is incredibly simple, and though the circuits do have some important particulars, they are not difficult for an electrical engineer to design. (And, that’s assuming that they actually get designed anymore. I strongly suspect that most folks are grabbing an existing design from a library and extending it to meet a certain specification.) Insofar as I can determine, there is no secret sauce to a summing bus. There are better components that you can specify, and due diligence is required to prevent external noise from corrupting the signals you actually want to use, but there’s no “magical addition process” that some folks have and some don’t.

“Doing stuff” to electricity that’s already electricity is pretty darn simple.

Life gets far more complicated when you’re trying to change sound into electricity or back again. The vagaries of directional microphone tuning, for instance, are strange enough that they don’t even make it into patent applications. They’re kept locked away as trade secrets. Microphone diaphragms aren’t really something you can build with ingredients found in your kitchen (good luck with working on materials that are only microns thick). Just about any decision you make will probably affect the whole-device transfer function in a way that’s easy to hear. On the output side, the tradeoffs associated with making a loudspeaker driver are both numerous and enormous. Everything matters, from the diaphragm material on up. The problem compounds when you start putting those drivers in boxes and attaching them to horns. Big drivers move lots of air, but don’t start or stop as fast as small units. The box might be resonating in a strange way. Just how bad do things get when the loudspeaker is run below the box tuning? Again, a small design change is likely to have audible results.

Manufacturers continue to iterate on transducer designs in ways that appear “fundamental” to the layman, whereas iteration on other products is more about incremental improvements and feature additions.

What this all amounts to is that a transduction improvement is far more likely to be of obvious and significant benefit than an upgrade in the “pure electricity” path.

Beyond The Chain

Upgrading the ends of the signal chain is a concept that works even beyond the electro-acoustical sense.

Let’s say I have the greatest microphone ever made. The entire thing is built from pure “unobtainium.” It is perfectly linear from 1 Hz to 30 kHz, and has infinitely fast transient response. It’s not even physically possible for this microphone to exist, it’s so good. I put that microphone in front of a singer with an annoying overtone in their voice. Does that singer sound good?

No. The microphone perfectly captures that ugly harmonic. If I had a choice, I would prefer an upgrade to the ultimate end of the signal chain: The signal source. I’ll take an amazing singer into an okay mic at any time, but a great mic in front of a bad singer doesn’t help very much.

Let’s also say that I have the greatest loudspeaker ever constructed. Its transfer function is perfectly flat, with flawless phase response. This mythical device is then placed in an aircraft hangar built of metal. The acoustical environment’s insane reflections and smeared transients result in a sound that’s almost completely unintelligible, and even a bit painful.

A “basically okay” loudspeaker in a great room would be much better.

If you’re going to undertake some sort of sonic improvement, you want to do all you can to upgrade things that are as close to the endpoints as possible. If you’re not getting the sound you want, look at source quality, room acoustics, mic capability, and loudspeaker fidelity first.