Friday, July 2, 2010

Public Address

The "PA system" (public address) is damn near as old as me. Maybe older. When I was a kid, an auditorium PA system was often a 15W Bogen tube amp and one or two Shure Vocalmaster columns. Some folks used Shure's mixer/power amp, but anyone who did that produced awful noises that couldn't be identified as either human or musical. The PA system has grown up in the last 60 years. It hasn't become better but it's definitely louder.

When I worked for QSC Audio in the 80's and 90's, we grew from a small company that made extremely solid, dependable, and reasonably good sounding amps to a major competitor in the pro audio field. During that period, pro audio went through some changes that it is still suffering from; the smaller and lighter is better movement. To be honest, the company that started that trend in power amps was Carver; with the PM 1.5. This POS amp was hyped as being able to drive 750W per channel into a 4 ohm load and weighed 16 pounds. When it clipped, it made exploding noises that often took out drivers. When it didn't clip, it was harsh sounding. If you pushed the amp hard, it would thermal cycle or die. Regardless, because it weighed a fraction of amplifiers with similar specs (more evidence that "anyone can write a spec sheet") the sound companies loved it. At QSC, we almost went broke before a few of our old customers came back to us after their Carver experiment.

Twenty years later, the whole industry is driven by Carver-style components: amps, speakers, consoles, and most of the signal path. Amps are multi-stepped or digital and weigh less than a 1960's microphone. Speakers are arrayed and tiny and sound like rejects from the Bose consumer product line. Consoles are digital and so menu-layered that most FOH mixers set 'em and leave 'em, regardless of how godawful the show sounds.

This week, I subjected myself to another round of suffering modern sound systems to get to see an old musical hero: Steve Winwood. Winwood was the intro act for Santana and I haven't seen Steven since Traffic. Since I had comp tickets (no concert sells out in 2010), the cost of seeing Winwood was whatever I paid for parking. Supposedly, the St. Paul Xcel Center is a great sounding room. I hoped that would be so for this show. It wasn't. As usual, the arrayed cluster-fuck of tiny horn boxes was tasked with the impossible duty of providing reinforcement for this large hockey gym. While the designers of the Xcel Center put a lot of work into deadening the room for musical performances, nothing those designers could do could have compensated for modern array speaker systems.

As best I can tell, the contract for all R&R concerts specifies a minimum volume level for shows. Nobody apparently cares how awful it sounds, as long as it is loud. In my 50 years in audio, I have never heard anything coming from an arrayed speaker system that is anything but painful and tonally irritating. Honestly, the theory behind these systems leaves me doubting the mathematical capabilities of the designers, but the practical application proves the theories to be flawed.

For the Winwood portion of the show, the system's resonances were somewhere between painful and obscuring. There was a pile of 70-400 Hz crap that the under-capable arrays failed to produce, so the system "engineer" (using that term grossly loosely) tried to correct with his subwoofer system. If you've read my take on subwoofers, you know how I am going to feel about this tactic. Winwood's bass came from the B3 petals. A B3's bass is one of the most totally cool bottom-end instruments ever invented, but you can't reproduce it with a pile of resonant horns. The sound is too complicated, too powerful, and too characteristic for a reproduction system that turns every LF note into "whoomph." So, the bottom end of the system was a muddy mess.

Winwood's voice was pretty well matched to the rest of the system's midrange capabilities, but everything else was reduced to OEM-quality car stereo fidelity and the FOH goofball's attempt to create top end from his garbage horns was painful, at best. I suspect the FOH doofus was running the system from his laptop, because I didn't see (or hear) anyone working the mix. It could be that he was at the audiologist's office getting his hearing aid battery replaced. If so, he didn't miss much.

Santana's set was about the same, only louder. He had a light show and a video screen to compensate for the lack of a sound system, but it wasn't enough. When my hearing protection was clearly failing to provide adequate protection, we left.

As usual, the show was about 1/3 attended with a substantial number of comp tickets given way to fill some of the empty seats. A lot of people gave up late in Winwood's set and left to save their hearing. When we were left, probably mid-way through Santana's set, we weren't alone in the parking lot.

I think, if live music ever hopes to make a comeback, sound companies are going to have to give up on the fantasy that light and small and loud are more important than fidelity. I'm unconvinced that making customers suffer for musicians' "art" is a winning tactic. Most of the under-30 crowd that I know consider major concerts to be miserable experiences that they hope to avoid for the rest of their lives. I'm starting to think they are right.

Wirebender Audio Rants

Over the dozen years I taught audio engineering at Musictech College and McNally Smith College of Music, I accumulated a lot of material that might be useful to all sorts of budding audio techs and musicians. This site will include comments and questions about professional audio standards, practices, and equipment. I will add occasional product reviews with as many objective and irrational opinions as possible.