Setup issue - heavy fret buzz past fret 12

Hi folks

I recently picked up a used MiA P Bass and I’m having issues setting it up. I’ve been doing my own setups for a few years now and wouldn’t consider myself entirely incompetent.

My issue is that I’m having heavy fret buzz past the 12th fret when the action is set to a reasonable level. To get no fret buzz, I have to set the action to upwards of 4mm on all strings over the 12th fret. If I lower the strings to 2.5mm action, the bass is basically unplayable past the 14th fret.

The truss rod is set correctly and there is no buzz anywhere else.

The action is a few mm lower at the 19th/20th fret than at the 12th fret. Looking at the bass I can kinda visually see the frets getting closer at fret 14 through to the end of the fretboard.

I took the neck off and there is no shim.

Not really sure what to do here, I guess I need the frets leveled? Or is there a greater issue with the neck? I don’t have this issue with any other bass I’ve owned and didn’t think to check this when I bought it.

Appreciate any help.

2 Likes

It’s hard to say without having the bass physically in front of me, but, generally, you should try setting your string action higher at the bridge after you’ve got the neck relief where you like it.

2 Likes

The neck relief is set properly and I need to set the action very high to avoid any buzz, close to 4mm at the 12th fret.

1 Like

Yes, but have you set your string saddle heights after you adjusted the neck relief? Just asking because that’s not clear.

A setup should, in order, include: setting the neck relief; setting saddle string heights; and, if necessary, adjusting string heights at the saddle. Setting string intonation follows the above process.

1 Like

Could be a “ski jump”:

If there is no shim then the Haze guitars ski jump seems unlikely. So, if the neck is straight, the nut is low enough, the bridge is set for 2mm action at the 12th fret and it still buzzes I would go straight to fret levelling but just from the 12th onwards. I normally do this when setting up a bass:
tape between the frets (10th to the end of the fretboard),
mark the tops of the frets with a Sharpie,
put two layers of tape on the 11th fret,
level the frets (12th to the end of the fretboard) with 240 grit sandpaper on a levelling beam, until the Sharpie is gone,
polish up with 600 grit, then 0000 wire wool.

2 Likes

Seems like the bass would need a fretwire work to me. Don’t know the word in english but in french we call that a “planimétrie” ; the idea is to sand the fretwires to make them flat relative to each other.

Otherwise, to be honest, the other solution is to find a compromise with the setting. A lot of my instruments, including my #1 bass and #1 guitar, have a noticeable fret buzz (action is relatively low on both those instruments) and it doesn’t bother me too much, I can live with it. What I want to say is that I can sacrifice this buzz to a low action. A matter of choice somewhat, and a compromise to find.

But a good luthier can make it all work for both a low action and no fret buzz if that’s needed.

2 Likes

Try to check the frets level using the rocker or credit card. What string does this happen to?

Yeah, a fret rocker is the next step. However it’s weird if there’s buzz on all of them above 12; usually a high fret causes buzz in the strings below it.

If you do find a high fret, the best thing to do is get a fret crowning file and fix it in isolation. No need to sand down all the frets for one high one. I would consider levelling all the frets to be overkill for a single high fret (or even a few). I have done this and had great results with a crowning file.

I really like this tool from MusicNomad:

https://www.sweetwater.com/store/detail/MN822--musicnomad-mn822-precision-fret-rocker

Combination fret rocker plus all the rulers you need for setups, metric one side, SAE the other.

I agree, sorry if my previous post was not clear about that.

1 Like

Not at all, I think it’s a common misconception and wanted to head it off :slight_smile:

Minor fret work is actually pretty easy.

1 Like