Fret Buzz on the first two frets of each string?

Your truss rod is probably tightened too much.

 

First couple of frets only sounds more like the nut. Did they file the slots down when they were lowering the action? They may have gone a bit far, take it back and ask them to fix it.

 

If the nut was filed too low, it will only create a problem with the strings open, not when they're fretted. It's more likely that there is not enough neck relief.

 

Is the buzzing when ya do open string? If so, probably the nut is cut too deep.

 

Press each string at both first fret and last, checking distance between bottom of string and top of 8th fret...

... nothing? A little bit of daylight? You could drive a Mack truck through it?

To check the nut, I usually press each string at either the 2nd or 3rd fret, checking the distance between the bottom of the string and the top of the 1st fret.

Not sure if OP explained if the buzzing occurred with open strings or when fretted.

 

Well yeah, I was guessing that was what the OP was referring to. Neck relief isn't affected by the truss rod that much up at the headstock end.

 

Fret buzz in the 1st - 7th fret while fretting a note is too little neck relief.
If your fret buzz is only on the first couple of frets but fine after then likely the 2nd or 3rd fret is too high. Or a marginally high fret combined with too little neck relief. It could be another fret slight further along too.
As others have said open fret buzz is too low a cut nut or a marginal to low nut combined with too little relief.
Take it back to the person who lowered the action.

 

If you paid someone to do it, make them fix it. And this time test it before you take it home.

This is why everyone needs to know how to set up their own instruments.

 

Yes! Plus, how is somebody else going to set it up exactly the way YOU want?

 

Unless you are really experienced with neck/file adjustment, you should know who the exceptional Tech's in your area are. They will set it up right.

 

Well, I don’t really think anyone is looking for a buzz on the first two frets.

 

Check out truss rod, neck status.

 

Sounds like the truss rod is too tight and you have a back-bow. The first few frets will buzz because they are right before where the neck starts bowing upwards thus the buzz is actually interference from the subsequent frets. This is typical when there is a back-bow even though you have set the string height to your liking.

Take a look down the neck with the strings tightened and then take a look down the neck when the strings are completely loose. If there's a back-bow, the neck will look straight, or less back-bowed, when the strings are loosened. Relieving the tension on the rod should alleviate the problem. If so, then you may have to re-adjust your string height once the rod is set to the proper tension and the neck is straight.

 

While it might certainly be a neck relief issue, ^^this^^ should also be checked. Allowing for more relief will fix the buzz, but if you ever want to get the action quite low, you want to make sure you don't have a high 3rd fret. I like to check by fretting behind the 2nd and in front of the 4th frets and tap the string on the 3rd fret. If you get a little sharp tap/click, you have some relief over the fret. If it's totally dead/silent, that fret might be just a hair high. It can happen even on really nice instruments and is easy enough to fix if you know what to do. Be aware though that there is a threshold of how strong you can make your attack when relief and bridge action are low. You trade oomph for finesse and vice versa when dialing in a setup

George

 

I highly recommend one of these to find high frets. It’s called a fret rocking tool.

 

The nut height has zero effect on fretted notes: it only effects the open strings.

The OP’s issue is either a fret or two being a bit too high, relief being a bit too low, or a bit of both.

 

The OP didn't mention whether they were on open or fretted notes, that was my (probably incorrect) assumption.

 

I would loosen the truss rod 1/8 turn. Let your bass sit for a day. Check the next day and loosen another 1/8 turn if needed.
A tool to check the neck can be bought for less then $20 on eBay.

 

^^^^This! Like others have said, loosen the truss rod about 1/8 of a turn and see what that does. Next time, don't take it to Guitar Center!