System Capacity and Gig Size
Will My System Fit the Gig?

What follows is all relative. The numbers are not absolute but as you become more experienced you will be able to to make them fit into your context as to what your system's capacities are.

I have been asked "What is a big sound gig?". The answer is variable depending upon where you are in your career and your reputation that precedes you. From a harpist's sound system capacity point of view it is a little easier to define. Just how big a system is a harpist willing to carry? (or her roadie?) That defines a big gig for that person in relative terms.

To be ergonomically acceptable (not too bloody big to haul around), small enough to fit in mini-van, cost effective, and give distortion free sound I believe a big gig is in about a 250 person capacity venue for a concert or 450 for background (ballroom size). Anything larger and you need a quantum leap in sound gear to have quality sound.

Why? I will introduce the concept of headroom. When the sound from your Celtic harp enters the microphone and is transduced into an electrical signal the result can be described as the program signal or material. The bulk of "program" uses about 1/8th of the system's electrical capacity. Periodically there are electrical spikes in the program signal that can use the remaining 7/8ths of the available system capacity. So electrically a well behaved and balanced system is "leveled" so that it for the most part it is coasting and there is enough reserve capacity for the momentary spikes in the live program material. That reserve capacity is called headroom. Sound engineers live and die by headroom.

If you have a small sound system and you push the signal levels up too high in order to get more volume you will start to get audible distortion of the sound because some part of the sound system is unable to transparently carry the signal at that level. The overall signal has to be reduced in the offending component part to what it is capable of handling without distortion. You need to ensure that there is sufficient headroom in each system component so that the variable 7/8th part of the program material does not overload and distort that component. A good sound system engineer will set his levels component by component to ensure a maximum signal path with a minimum of 18-20 db headroom throughout.

In harpist terms this means if a system is pushed beyond capacity you get audible distortion and almost immediately the distorted sound causes feedback. Your audience knows immediately when you push a system too hard. Ouch that hurts!

A very ruff guide - my best guess as there are huge variables:

A comment is necessary about component quality. Musical Instrument (MI) stores abound in shopping malls. They survive by selling to 18 year old boy guitarists with $200 in their pockets. MI sound gear is designed for that market with a $200 price point. What goes inside the box does not matter as long as it looks sexy. Harps are exceptionally hard to amplify as they are natural microphones and co-resonate with rooms and the attendant sound systems to cause feedback very easily. In the chart above I have graded systems in part by their ability to handle feedback issues. Buy componentry from specialist audio stores, the web, eBay(?) and use the web extensively for reviews (learn to read between the lines as to what the reviewer's intent is).

It goes without saying but I say it often as possible to reinforce the notion - you get more headroom with quality components. Buy quality. If you cannot afford quality now wait until you can. It is worth it!

I will add your knowledge and experience to the “mix” if it can add to the effectiveness of these articles. The rest of the Celtic Harp Amplification Series is available here.

Stephen Vardy
Harpsound Audio
[email protected]