Using Onstage Amps vs. Playing Through the PAMay 2, 2008 7:21 am Live Sound
For the last several years I have been running sound for a central Ohio two-guitars-and-keyboard oldies band known as Rusty Strings. We started out using a Kustom KPM8420 powered mixer and have recently upgraded to a setup with a separate mixer, effects unit, and power amp. One of the issues we have had to deal with is whether to run the guitars and keyboard through the PA along with the vocals, or leave them out of the PA and rely on onstage amps for the instrument sound.
The main guitars are acoustics with pickups. We decided to use the pickups rather than miking the guitars themselves in order to avoid problems with feedback and leakage. (The tradeoff is that the pickup sound can be somewhat different from the actual sound of the guitar, but unless you are Andrés Segovia this probably doesn’t matter.)
When we first started playing, typically in restaurants and at parties, we ran everything through the PA - the two guitars, the keyboard, and three vocals. On some songs, one of the guitarists switches to bass, so we ran that through the PA as well. The onstage amps (small “combo” type units) were putting out some sound, but the audience was basically hearing everything through the PA.
The connections themselves were straightforward. One of the guitar amps has a direct output in the back, so we ran that straight to the PA. For the other guitar, we put a DI (direct input) box between the effects unit and the amp and ran its output to the PA. The keyboard was sent to the PA through another DI box and also separately to an onstage amp, using the L and R keyboard outputs. (Make sure all the keyboard voices are mono if you do this!)
One of the main problems with this whole approach, it turns out, is that it uses up a lot of PA power. When everyone was playing and everyone was singing, the PA was really straining. When the bass was in there, the Kustom really just couldn’t handle it. I remember one gig where a guy who “knew about sound” came up to me during a set to report that one of our main speakers had a “tear” in it and was sounding really bad. Panicked, we checked it out at the next break, but it was fine. What our knowledgable friend was actually hearing was good old PA overload distortion, plain and simple.
We Gotta Do Something
At this low point, we realized two things: (1) the Kustom PA was somewhat underpowered for the venues we were playing; and (2) we should rely more on the onstage amps and less on the PA for the instruments, leaving most of the PA power for the vocals. Realization (1) led to the purchase of the new gear. Realization (2) led to a different approach to using the PA.
Our first thought was, “Well, let’s use the PA only for the vocals and turn up the amps onstage for the instruments.” The trouble with this is that the sound man (ahem) loses all control over the levels of the instruments relative to each other. In songs with lead solos or distinctive riffs or parts that must be emphasized, I had grown accustomed to “bumping up” the appropriate instrument during such a part, much as I might make a “fader move” while mixing a song in my home recording studio. With no instruments in the PA this would be left up to the players, who are in a poor position for hearing how much to “bump themselves up,” and are too busy trying to remember their parts to bother anyway!
Our solution was to adopt a hybrid approach. We still run all the connections from the instruments to the PA just like we always did, but we also turn up the amps onstage to performance level. During the soundcheck (also known as the first song of the first set) I start out with the PA instrument faders all the way down and quickly set up the vocals to match the level I am hearing from the instrument amps. Sometimes I need to bring up one of the guitars a bit (since I can’t turn the other one down!) to get them balanced with each other and then re-tweak the vocal levels. I also usually need a little bit of keyboard in the PA mix as well as it tends to get overwhelmed otherwise. In the end, once it’s all set up, my “basic mix” is at least 80% vocals.
From this point on, I operate pretty much as I did before. I have my set list with its notations of lead singer and lead solo player for each song (thank you Rusty Jack!) so I am always ready to “bump” the appropriate faders as needed to temporarily beef up the sound. During a solo, the audience is hearing the instrument through both an onstage amp and the PA; at all other times it’s basically just the amps.
One final point. With Rusty Strings, the two main PA speakers are always to the left and right of the playing area, so they are about the same distance as the onstage amps from any particular audience member. If your setup has remote PA speakers, say towards the back of a room or in a bar area, you will need to put a bit more of the instruments in the PA. Otherwise, listeners near the remote speakers will hear a mix that is heavier on the vocals than it should be.
In the end, the moral of this story is: if your PA is straining under the load, try using onstage amps for your instruments while also running them through the PA for fine balancing and occasional emphasis.Tags: live mixing, PA systems -->