The Grateful Dead's PA system

#2
I have a framed 16" x 101/4" photo of that very shot in my music room. That particular system was only used from March 23 - September 20, 1974 (and the center vocal console over the drums was introduced mid-year, I believe). Late in '73 they had some prototype evolution going on, however. One of the primary features of the system was phase-cancelling microphones (actually two microphones on the same stand) that allowed for the PA speakers to be behind the band so the band "heard what the audience heard." The result was apparently startling. The vocals to take on something of a tinny character as a result; however, the GD were playing large, outdoor gigs fairly often in the summer of '74 and this system allowed them to fill those venues with sound.

If you can bear to do it, drag the slider below to 1:17:00, let it load, and give it a listen for about two minutes of your life (headphones encouraged). At 1:17:28, you can hear Keith click on his wah for the electric piano on the left. Shortly thereafter, Jerry goes off the rails a bit while the band slogs along with their elastic groove and it all comes crashing back nice and crisp at 1:18:13. The Feelin' Groovy jam at 1:19:01 is really nice, if you can make it that far. :wb:

 
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mjp

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#3
The vocals to take on something of a tinny character...
Yeah, as someone pointed out in that article, you can't really use two microphones to do reverse phasing in a live situation like that and have them sound good. You can't really do it anywhere and have it sound good. It's a good concept, that's about it.

Bob Heil built reverse phasing in to some of his microphones (and the Grateful Dead used his PA systems before they built the wall), but the idea with any microphone is to reject sound behind it or to the side of it, not in front of it. So when I read that the vocal mics were in front of the PA speakers I knew they had to be doing some kind of noise canceling. And noise canceling always has a negative impact on the sound.
 
#4
Missing from the article you linked to are some specs (although these might be in the attachments/clickable figures), thanks to Light into Ashes and his great website. A quote from: http://deadsources.blogspot.com/2012/12/1974-wall-of-sound-technical-specs.html

The whole system operates on 26,400 Watts of continuous (RMS) power, producing in the open air quite an acceptable sound at a quarter of a mile and a fine sound up to five or six hundred feet, where it begins to be distorted by wind. A sound system could get the same volume from half as much power, but it wouldn't have the quality.

I see what you're saying (and have always wished I could have seen and heard it), mjp, about wishing you could have heard it - a fine sound up to five or six hundred feet and an acceptable sound at a quarter of a mile? Great googly moogly.
 
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#6
I saw The Wall of Sound at The Cincinnati Gardens 12/04/1973...They started using it or a version of it, the fall of 1973. The official " grand opening " was 03/16/1974 which I believe was issued as a Dicks Picks. The Cincinnati Gardens was/is an old basketball area, that had the acoustics's of an empty airplane hanger. Part of the concert was released as a bonus disc with the Winterland 1973 Box Set , and sounds terrific. Hearing it live, not so much..
 
#10
Throw in Boston Garden, Winterland and a host of other steel and concrete venues and there was no shortage of craphole-sounding places they played, but all of the '74 shows I've heard have a warmth (vocals notwithstanding) to them that's pretty remarkable. I suppose coming from the board to reels helps greatly in that regard. I think the real benefit of the WoS was for large outdoor venues such as Iowa State Fairgrounds (6/16/74), Dillon Stadium (7/31/74), and Roosevelt Stadium (8/6/74), where someone 100 yards away had as clear a sound as someone in the front row. Maybe not quite as loud, but of equal clarity.
 

mjp

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#12
Eh, I dunno, man. A board tape is completely removed from what an audience hears, so using them as demonstrations of how awesome a PA system was doesn't make any sense. You'd need audience recordings made with microphones to prove that point. Unless they want us to believe those are audience tapes? I don't know. Maybe they are. But they sound like board tapes to me, in the video here. There is no ambiance.

I would also have to argue that someone 300 or 500 feet from the source is never hearing the same thing someone at the source of the sound is hearing. Speakers are speakers, however you arrange or stack them. In an arena or a theater, there's reverberation bouncing off all of the many hard surfaces, and there's nothing you can do to avoid or "mix around" that.

Outdoors might seem better, but it's actually worse. The sound dissipates very quickly, low frequencies travel further than high frequencies, the wind can change the sound, and there's also reverberation outdoors, though it's usually not as horrible as something like arena reverberation.

I've mixed shows in huge, ancient stone amphitheaters, smaller modern outdoor amphitheaters, a tiny (concrete) amphitheater at Santa Monica College, in city parks, on city streets, and even a velodrome (a bike racing track, this particular one was built for the 1980 Olympics in Los Angeles), and I can tell you from painful first-hand experience that getting good, consistent sound outdoors is like trying catch the smell of daisies in a jar and save it for a Christmas morning sniff.

It's a cool hippie thing they built there, it's actually kind of awe-inspiring, that mountain of speakers. But they're still just speakers. I get the feeling the thing they built has been mythologized a bit. But I guess you'd have to have been in their audience in 1974 to know for sure. Though in 1974 I'd imagine that most of the Dead audiences were too full of drugs and/or herb and/or warm wine drunk out of one of those vile pigskin things they carried over their shoulders to really notice.
 
#13
Those aren't audience tapes, they are board tapes used for a very recent boxed set (at least those in the video from '74 are). There are audience tapes from the period on the Internet Archive and Relisten that give a better sense of what the WoS sounded like (but not in similar fidelity). I agree that the board is not a fair representation of the stage sound.

A few guys over on SH forums attended shows back then and the general word is that the sound was quite impressive even at the far end of a stadium. I agree that there will always be some interferences, but the WoS did as well as any system in terms of creating a faithful sound at substantial distance from the stage. Without the need for these.
 

mjp

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#14
Yeah, in a festival-sized crowd you need those remote PA towers. I only worked with them once, at a festival in Switzerland that about 50 people ended up attending due to unseasonable cold and rain. Quite an evening. After the first song, one of our guitar players yelled into the mic, "GOOD EVENING EUROPE!" which was about the funniest thing I'd ever heard. Under the circumstances, anyway.

We sat in the back row of the Hollywood Bowl a year or two ago for the Brian Wilson Pet Sounds concert, and the sound was clear enough, but every time a much needed summer breeze blew, you could hear the sound blowing away with it. I just checked Google, and the back row of the Bowl is 450 feet from the PA.
 
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