You can download the PDF of this resource here.
Working with the sound engineer as a guitarist
As a guitarist, especially if playing electric guitar, a good relationship is needed with who ever is operating the sound desk. The congregation will only hear good tone if both the player and the engineer are working together! Often as electric guitarists we like to have our amplifiers turned up fairly loud, for several reasons (some amps sound better if loud, amp is able to be heard/used as a monitor), however for a sound engineer this can potentially cause problems. They have responsibility for mixing the whole band, and they need to be able to place your guitar in that mix - if your amp is too loud then it may end up being too prominent compared to the other instruments. Being told to turn our amps down can often be frustrating for us as guitarists, but we need to honour our sound engineers and respect the fact that they have been given responsibility for the mix due to their gifting, and we should always be willing to listen to what their preference would be for our sound. Sometimes this stretches beyond just volume adjustments, you may be asked to take some of the high end out of your amp, or similar EQ tweaks - again we need to respect the sound engineer and his/her role and responsibility.
Controlling the amp
If you are repeatedly having problems with the volume of your amp (as I said, some amps just sound better when they’re loud so you may want to keep it that way, OR you may have turned it down, but it's still too loud!) there are some things you can do to help besides just turning it down.
You might consider putting the amp in a different room, or underneath the stage if you have that sort of space. Or if those options aren’t possible, trying facing your amp away from the congregation - either against the back wall, or in front of you so the speakers face you. Another option would be to invest in some perspex screens (similar to the drum screens often used in churches, but smaller!) to place in front of the amplifier. All of these options should help to reduce to stage volume, and allow the sound engineer to achieve a better, more controllable mix.
Hearing yourself play
Of course, if you do move your amplifier away from you at all, you may not be able to hear it as well, if at all. This will mean you will need to rely on your sound engineer to feed you some of your guitar through your monitors (I would recommend in-ear-monitors!). Again, trust your engineer to do the job that they have been given to the best of their ability, and build a good relationship with them. Help them with understanding what you need from them, and be open to understanding what they need from you.
Getting your tone right
One final thing to add is that you may need to spend some time working with your sound engineer on EQ-ing your guitar on the desk. The electric guitar is very versatile and can change sounds several times even in one song, so work hard with your engineer to find an EQ setting that sounds as good as possible. I find it usually works best if you start at a flat EQ, and start to tweak the high end if necessary, maybe removing some of the low end too. This allows the guitar to sit nicely in the mix, whilst cutting through if needed during a higher lead line. EQ can take time, and may need a lot of tweaking, but do take the time to work on it together, it’s well worth it - If you have a really top engineer then they may even edit the EQ as the song goes along!