Tuning new mandolin

[NFLDMandolin]

I have a new Johnson mandolin and it is basically a starter. I tuned it with an electonic tuner and when I play a D and an A is sounds o.k. But when I try a G or C it is awful?? I assume that I need to take it to a music shop and get the bridge set correctly? Any suggestions?? Can I tune this instrument myself somehow??

Rick http://www.mandolincafe.net/iB_html/non-cgi/emoticons/sad.gif

[jiffyfeet]

It sounds like the bridge probably isn't in the right place, like you said. You can try to do it yourself if you think you can do it. You may as well give it a shot before you pay somebody to do it for you, if you ask me.

Since you have an electronic tuner, get the note perfect with an open string like you normally would, then try it at the 12th fret and see what it says. If it's flat, I think you need to move the bridge towards the fretboard, thereby decreasing the amount of string between the fretted note and the bridge, making it higher pitched. Likewise if it's sharp, you need to move the bridge towards the tailpiece in order to lengthen the string and lower the pitch.

I think that's right. I did mine myself, and it was frustrating but I eventually got it. It's a pain because you have to loosen the strings quite a bit before you can slide the bridge, especially if you have any regard for the instrument's finish, and you aren't likely to get it just right in one try. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/tounge.gif

[Dru Lee Parsec]

Without the tuner (just listen by ear) play the G string at the 12th fret. Now play the 12th fret harmonic. Are they the same note? If the fretted note is higher than the harmonic then the bridge needs to be moved towards the tail (away from the fretboard). If the fretted note is lower than the harmonic then the bridge needs to be moved closer to the fretboard. With a Johnson you could probably move the bridge with the string tension on, but I wouldn't do that with a nice instrument. You should probably loosen the middle strings to adjust the bridge.

You need to do that with the low G string and the high E string. The bridge placement will end up being at an angle.

[grsnovi]

A general rule of thumb is that on floating bridge instruments, the bridge will usually line up between the mid-points on the f-holes. In terms of measuring, the distance from nut to bridge should be 2x whatever the distance is from the nut to the 12th fret. Then, the bass side will likely need to be a little bit more (possibly 0.03125" or so) - then you need to do the fretted/harmonic hearing test as described above.

The "mnemonic" for setting intonation is: Fretted, Flat, Forward (ie: if your fretted note is flat compared to the harmonic note, you need to move the bridge forward towards the nut).

Get the bridge in the approximately right place as measured first.

[Dru Lee Parsec]

NFLDMandolin:

I should have mentioned that on my Johnson mandolin the bridge was stuck onto the body with some double sided foam tape. #That causes several problems:
1) It's difficult to move the bridge
2) There's a piece of foam between the bridge and the body. #That will cut down the transfer of vibrations to the body.
3) It makes up for having the bridge not fit the body well.

So now that I think of it, I'd suggest that you do what I did. #Take all the strings off, remove the foam and clean the feet of the bridge and the top of the body with some alcohol to get the residue off without damaging the finish. Get some new strings to replace the junk that comes with the instrument. #I like www.webstrings.com (http://www.webstrings.com) (no affiliation with them, they've just always given me good service and good quality strings)

While I had the strings off I went ahead and "painted" the tops of the frets with a black sharpie pen. #I then quickly ran a diamond stone over the frets to see if they were flat (they wern't). #Sure enough there were 2 very low frets right where I was getting some bad buzzes. #Now, I build instruments so I had fret crowning files, but if you get to this point and you see that the frets are seriously bad then you will probably want to take it to a repair man. #You may want to skip this step since it's an inexpensive instrument (mine was the $59 A-Style).

Now, put the bridge back on the body by hand and look at how the feet fit the body. #On mine only the very tips touched. #That was one of the things the foam tape was hiding. #You want a perfect fit between the bridge and the body and it's easy to do. #Just lay a piece of 100 grit sand paper (grit side UP) on the body and lay the bridge on top of the sand paper. #Take very short strokes in the direction of the strings and you will quickly sand the bottom of the feet to fit the mandolin top perfectly.

Taking off the foam tape will very slightly lower your action. #This may or may not be a problem. #The action on my Johnson A-Style was way too high to start with so it wasn't really an issue to have it lowered.

Put one high string and one low string on and set the bridge location using the harmonic method I described above. Get the bridge in the right position and then put the rest of the strings on. #Now guess what? As you tighten the strings the bridge will want to roll towards the fretboard. #So you may want to roll the bridge towards the tail piece a little bit before you put the rest of the strings on to compensate for this.

The last thing I had to do was to lower the action at the nut. #If you press down on the 3rd fret then the strings should just barely clear the first fret. #The nut on mine was WAY too high. #This, however, is probably a job for a repair man. #But at least you can check it to see if it needs the work done.

So I guess I'm saying that you can get the bridge position in the right position and change the strings yourself, but if you have low fret issues and an incorrectly set nut (which is quite common on these inexpensive Johnson mandolins) then you may want to take it to the repairman. The bad news is if you paid around $59 like I did then the repairs may cost you almost as much as your mandolin. The good news is if the frets are level and the nut and bridge are set up correctly then these little Johnson mandolins actually play pretty darn well. #I learned a lot of music on mine. #I eventually upgraded to a Breedlove, but once I cleaned up the action on the Johnson it wasn't a bad little mandolin at all. #And certainly if your instrument is set up correctly and it's not "fighting" you as you try to play it then you'll learn a lot faster.

I hope that helps. #You're welcome to private message me if you have any questions.

[NFLDMandolin]

Thanks guys. I will take your advice and give her a try. I think I'm a little too anxious to get at it. I will take my time and try to set it up as best as I can.

Thanks again.

Rick

[mpeknox]

Try this (http://www.frets.com/FRETSPages/Musician/Mandolin/MandoString/mandostring3.html) for instructions on setting your intonation...it's not too hard.