This is one of my my favorite subjects.

95% (I like using random percentages to make a point) of the folks on the internet expressing a preference for “pure nitro” or “nitrocellulose lacquer” don’t have a clue what they’re talking about - they’re simply regurgitating the crap spewed by someone else, who got it from another “spewer”, etc. etc. etc.

FACT #1: Paint - or Coatings, or Lacquers, or whatever the term - does NOT “have” tone. It also does not affect tone unless it’s REALLY badly applied.

Offender #1: Polyester, aka “Poly”, aka (often mistakenly) Polyurethane, aka any thick, glossy coating on a guitar that’s perceived as NOT being the revered “nitro”.

This is described as “thick and gooey” and “the plasticky looking stuff Fender used in the 70’s”, along with ways of recognizing if you have it (Ed Roman’s site recommends removing a strap peg and looking for “filler” - he doesn’t clearly say WHAT filler looks like, only that you find it there and “thickness is the key”. Oh. OK. Typical of the information floating around the internet that does you absolutely NO good.)
  • Problem #1 - If you do any reading about vintage guitars, you’ll find that Fender used a primer/filler under their solid-color finishes in the 50’s. that material was “Fullerplast” - and it was a POLYESTER COATING. Ergo, using the logic of the Vintage Police, any guitar with Fullerplast on it must sound like crap, because polyester “has bad tone”.
  • Problem #2 - Roman is partially right here; thickness plays a key role in the tone enhancing or deadening of a wood body - but only in extremes. Yet most finishing sites recommend applying (in some cases) dozens of coats of nitrocellulose lacquer to get a good looking finish with some “depth”.
  • Well - just how thick are these things, anyway? Answer - not very. A container of lacquer actually consists of a very small amount of what actually remains on the surface. There are very specific tools used in the coatings industry to measure “wet film thickness”, and calculations that tell you what the final “dry” film thickness will be once the stuff has dried/cured and the solvents have evaporated. I’ll avoid getting too technical - but generally when lacquer, for example, is dry it’s less than a third as thick as when it was applied. I don’t know of any “garage finishers” who actually know how thick they are applying lacquer (or whatever). But with the amount of lacquer lost during application (overspray, bounce back etc) and the drying process 20 coats of lacquer is (in the paint world) a very thin total amount of coating. BUT - apply 20 coats of polyester or polyurethane and the rules can change, because the amount of coating left after curing is far more per coat than it is with lacquer. So how to you avoid thick, plasticky looking “poly”? Don’t apply very many coats. Why were many 70’s/80’s guitars coated with gobs of goo? Because of the fairly primitive application methods and because some engineers (not players) felt thick coatings would result in less checking and damage and fewer complaints. And they were right. The *average* player who doesn’t spend hours a day surfing the net (instead of playing) doesn’t know he’s getting lousy tone (because he’s probably not - maybe there’s some damping of vibration, but not to a huge degree.

There are still differences - lacquers continue to “cure” almost indefinitely, which is why you see nice, glossy lacquers on new guitars and lots of grain texture on old ones - the stuff shrinks down into the grain. Lacquer also “breathes” (to a point), letting small amounts of moisture into and out of the wood - which is good for the wood itself.

But boil this all down -

There’s no tone difference between lacquer, polyurethane, polyester, stain, house paint, car paint, fingerpaint…

The tone is affected to a noticeable extent only when coatings are applied in the extreme.

Side note - ever seen anyone complain about the tonal affect of oddball stuff like meters sunken into a guitar’s top, or graphics made of metal, or how detrimental binding is to a guitar’s tone, or the type of pick guard?

All those things add weight, change the rigidity of the body and must affect vibration as a whole. But no, we only flip out over “poly”…

Last point on coatings (of now) - much is said about “pure nitro” and that it’s the ONLY thing that should be used (and was what was used by companies like Fender in the 1950’s/60’s).

Guess what? Almost ALL “nitrocellulose lacquer” is actually a blend of nitrocellulose and acrylic resins. And has been since the 50’s. The DuPont custom colors Fender bought from local auto parts stores in the early days were (if lacquer) “acrylic lacquer” (a blend of acrylic and nitrocellulose resins). And in some cases, they used enamels - oil based paint! Yet we see posts on finishing forums by by inexperience “refinishers” worried about using auto acrylic lacquer from Pep Boys when they’ve had it drummed into their heads they need “nitro”. Reality Check - the stuff on the shelf in auto parts stores is VERY close to the original stuff Fender and others used in the 50’s!

My point - don’t worry about whether you are buying “pure nitro” or “acrylic lacquer”. Even if you DO find pure nitrocellulose lacquer it’s perfectly compatible with (as a top coat or as a coat under) acrylic lacquer.

Feel better?