Postby Mr. Bill » Fri Jan 20, 2012 1:46 pm
It doesn't really matter if it's a Mosrite or not or even if it is a bass or a guitar, basic set-ups are pretty much the same. Learning a few simple things will not only save you money, but will make the playing easier, better and will improve tonality as well.
First to answer your question, yes having a zero fret eliminates nut adjustments. The zero fret and string spacer replaces the normal nut's functions. They also eliminate the need for nut slotting, which is or at least should be treated as a true art form.
Truss rods are very simple things, but they can cause all sorts of headaches. The basic purpose of the truss rod is to counteract the effect of string tension on the neck. Most basic truss rods work well enough, but if you don't approach the adjustment carefully, you can cause all sorts of problems. A neck can have structural issues that no amount of truss rod adjustment can fix. This often leads to broken rods or damaged necks. Never try and force a rod that won't turn! If you're lucky enough to know someone that knows how to adjust a rod correctly, as them to show you how to do it. If not, then just take your time and approach it with a little caution and you should be fine.
The idea is that the neck should have a slight curve to it when it is under normal playing tension. This curvature is called "relief". If you hold down the lowest string on the instrument at the first fret and at the highest fret you can compare the straight edge of the string to the straightness of the neck. There should be a little space between the string and the top of the frets along the middle of the neck, maybe around the 7th fret for example. Most guitars play well if there is as little as 1/16-1/32 of an inch. Basses tend to need a bit more, maybe 1/16-3/32. If the relief is too great, the action will be higher and the guitar will be harder to play. If the relief is too little the strings will buzz all up and down the neck.
If the neck has too much relief or bow, the truss rod needs to be tightened. On most guitars you tighten the rod by turning the nut clockwise. Never turn more that 1/4 turn at a time. If it takes a lot of torque to make the adjustment don't try and force it or you may break the rod. It may be best to have a repair person check it out. The last thing that you want is a broken truss rod. If you take it slow the neck will start to straighten out and the space between the string and the top of the frets will get smaller. Adjust it and then play the instrument. Look to see if there are any positions where the strings start to buzz or rattle. If there are, you may need to loosen the rod or raise the string height. Remember if the entire neck is not level and even, you will need to make adjustments based on the worse part of the neck.
If the strings are too close to the frets the rod will need to be loosened. Again adjust the tension slowly and never force the rod.
Once the neck is adjusted, the string height will need to be set. Some of this setting will be based upon player preference, so minimally set it so that the strings do not buzz when played. They may need to be raised if the player prefers them higher or if they squeeze the strings and the strings get choked due to the curve of the fretboard. If the saddles are individually adjustable for height, be sure to keep the strings arced to match the fingerboard radius.
The last string adjustment is for scale length or intonation. The bridge saddles need to be adjusted so that the string plays in tune both in open position and at the higher frets. The best way to do this is to use a strobe or some other form of electronic tuner. The strings need to be new and of the correct gauge when you set the intonation. It will need to be redone if you change brands or gauges of strings.
Use the tuner to tune the string to the correct pitch. Now fret the string at the 12th fret and see if the note is flat or sharp. Be careful not to stretch the string while fretting or it will cause the string to go sharp. If the note at the 12th fret is sharp the saddle needs to move away from the fretboard. If it is flat it needs to move towards the neck. Adjust each saddle until all strings play in tune at the octave. Some guitars will require minor adjustments to the string height if the saddles are moved a lot in either direction.
The final adjustment that I make is pickup height and balance. I like to set the bridge pickup high close to the strings, but not close enough to either interfere physically or magnetically with the strings. Then I set the neck pickup usually lower so that when both pickups are on there is a slight bit of tone/phase cancellation. This way when switching from neck to bridge there is a fairly even volume setting.
I hope that this helps.
