Fret buzz between 2nd -4th frets

Yes. Generally, buzzing in the lower register only is an indication of insufficient relief.

Check string height first though to make sure your saddles haven't dropped.

You'll most likely only need to turn it a little bit counter-clockwise. Say, 1/8th?

 

I agree but check the bridhe heigth before adjusting truss rod

 

Does the string height of all strings follow the curvature (radius) of the neck, or are they all pretty much flat when viewed from the side?

If only the A and D strings are causing problems, it sounds like you need to move the saddles so they're the same distance from the neck as the E and the G are.

If you like more of a flat set up, you'll have to put up with pretty high action on the E and G strings to achieve it.

 

Almost always a too flat neck causes this.

 

The neck is too str8. You have to add some relief to the neck.

 

In general how's the action? Maybe you havn't added enough relief. Did you adjust the saddles to tweek the radius?

 

The Fender specs are just a suggestion. You have to get this puppy to a place that you like. Unless the action is feeling high "I" would give it another qtr turn . It certainly wont hurt to try it.

 

Here's a story for you: A guitar player (I'm pretty sure it was Chet Atkins) had two identical guitars, same year and everything, and one of them had a buzz which no one could get out on certain frets. So, eventually they took it to somebody's lab and used slow motion photography and found that on one of the guitars the path of the string's vibration caused a more downward arc. Even though they were made from the same type of wood, the best theory they could come up with was that it was actually some property of the wood in the buzzing guitar (maybe a little denser or something).

Hopefully, thats not your problem. Thicker gauge strings vibrate less, also flatwounds. New strings will, of course, make more noise then worn in, yet usable strings.

 

Here's a question: Do you have an early or late '76. Does it have the "TV" large letter logo or does it have a serial S6 on the headstock.

Oh yeah, and higher gauge strings can wear out your truss rod and frets quicker, but over a very long period of time.

 

Oh....didn't see that one coming. Its the early-mid 70's necks that are notorious for their problems at both extremities of the fretboard, not usually the serial numbered ones.

Since you've already raised the saddles and loosened the truss some and checked the strings, I'd suggest taking it to a luthier. Not one where you just drop it off, but someone who you can show the problem to and will tell you what their solution is and how much it costs. It seems to me that the truss being slacker should take it out, but I feel that its generally a bad idea to give truss suggestions to people I don't know, especially on vintage instruments. Check out fretnotguitar.com, great site, great luthier. She explains a lot about truss's and everything else.