There are many reasons for determining the precise age of your used guitar. The most important one is probably pricing the instrument appropriately when you’re looking to sell it. Prices for certain vintage models vary by thousands of dollars depending on whether it’s a 1963, for example, or a 1964. You’ll also need to know exactly what your guitar is worth for insurance purposes.

One of the most valuable and often overlooked resources to help you identify and appraise guitars is your local used instrument dealer. It’s so important to establish a working relationship with these folks. While it may be tempting to call every store in the area in order to save a few dollars when you’re shopping for something, developing a loyalty to one or two shops pays off when you need service that goes beyond a simple purchase. While most shops charge a fee for an official appraisal, it may take an experienced retailer only a second to realize that your old Epiphone is actually a Nova 390, produced from 1976 to 1980 in the company’s short-lived Japanese factory. The shop employee may be glad to look up the approximate value of your ax in a book and give you an opinion about what it’s worth. But if you randomly drop by a store that you’ve never been to before and ask for this kind of help, they might not take the time to look carefully at what you’ve got.

LEARNING THE HISTORY

If you want to educate yourself to identify guitars, the first step is to become familiar with the histories of some of the larger companies. In recent years, more and more books providing information on the major guitar manufacturers have become available, and they’re a great place to start. There are some basic questions to ask. When did the company start building guitars? Where were the guitars manufactured? Did the company move in the course of its existence, and did it move its production overseas? Did the model in question change drastically during the years of production? For example, Gibson’s J-200 started out with rosewood back and sides and fairly standard X-bracing in the late 1930s. It was changed to maple back and sides (except for a few rosewood examples) and a double-X bracing pattern in the ’50s. Yet another double-X bracing pattern was used during the ’70s, and then a more Martin-like scalloped X-bracing was adopted when the model was reintroduced in the late ’80s. These are all differences that would be difficult for the uneducated eye to notice, yet they drastically affect the guitar’s sound and value.

At the very least, these books will identify the time period during which the guitar in question was produced, basic information that will, for example, keep you from paying a premium for a "1960s Martin HD-28" (you’ll know that this model wasn’t introduced until 1976). Sometimes you can narrow down even further the time period in which your guitar was built because of a certain distinguishing feature. For example, a volute or scroll at the back of a Gibson headstock usually indicates that the instrument was built between 1974 and 1981 (although some appeared as early as 1969).

Another thing that the trained eye will immediately be able to pick up on is whether an instrument was built in the U.S. or imported from one of the many low-end Asian manufacturers. When I worked in retail, a customer once walked in with a Ventura archtop for sale. Convinced that he had a guitar that was built in the U.S. in the ’50s, he stormed out after I told him what I’d be able to offer him for it. Even if I hadn’t known that Venturas were made in Japan during the ’70s (which was confirmed by a quick look in the Vintage Guitar Price Guide), I knew as soon as he opened the case. It was mostly the guitar’s thick finish that gave it away, complete with lacquered neck-to-body joints and drips through the f-holes. The wimpy hardware was another dead giveaway that this guitar was neither domestically made, as he thought, nor a high-quality import. The best place to gain this kind of familiarity is at your local music store’s used-and-cheap section; the more guitars you inspect, the more experienced you’ll be.

One of the biggest roadblocks in identifying a guitar can often be the serial number. These numbers are frequently inconsistent or missing from reference books. In many cases, a serial number by itself is about as useful as a phone number with a missing digit. Few companies have consistently used the same system of numbering during their entire existence (Martin is among those that have). For example, Gibson began using an eight-digit number in 1977. The first and fifth digits indicated the year of production (8XXX2XXX meant it was built in 1982). If you tried to apply this formula to a serial number on an older Gibson, or even a newer vintage reissue (which sometimes use "vintage" serial numbers) you’d be making a big mistake.

REFERENCE BOOKS

So, how does one go about accurately identifying a used instrument? Probably the publication most often referred to is Gruhn’s Guide to Vintage Guitars. Written by George Gruhn (of Gruhn Guitars in Nashville) and Walter Carter, the guide is a must-have for identifying older American-made guitars. Organized into brands, general information, serial numbers, specific features, and model designations, the book identifies most major-brand guitars of the past and offers meticulous descriptions and a wealth of helpful photos. It offers little or no information on smaller makers, budget instrument makers, and recent entries into the guitar market.

Although designed to give approximate values for vintage instruments, the Vintage Guitar Price Guide is also quite useful in identifying instruments. While it doesn’t describe each model’s features in detail, it does provide a company history for most of the makers included. The book’s many photos can be very helpful, and the general listings, which include many off-brands, are among the most complete available. As with all price guides, the dollar amounts shown are to be taken with a grain of salt, but having even a vague idea of an instrument’s value will make you a more savvy buyer or seller.

Another excellent resource is the Blue Book of Guitars. This hefty book probably represents the most complete compilation of information on guitars that have not yet reached vintage status. It’s one of the few books that lists instruments made by companies such as Kay and J.B. Player and by individual luthiers such as Dave Maize and Steve Klein. Besides retail price information, the book includes brief descriptions of most companies and models listed, as well as a unique section on grading the condition of an instrument. In a color section, a variety of guitars are pictured front and back, showing a range of possible conditions--from 20 percent (poor) to 100 percent (new).

You can also join guitar-related newsgroups on the Internet, but beware of advice from uneducated participants posing as guitar experts. Of particular interest to acoustic guitarists are rec.music.makers.guitar.acoustic, rec.music.makers.guitar.jazz, and rec.music.classical.guitar. You might also check out rec.music.makers.guitar and alt.guitar.

These resources and the others in the Acoustic Guitar Owner's Manual should help you on your way to becoming a guitar expert. All you need is hours and hours of paging through every available book on the subject, countless weekends spent at guitar shops and vintage instrument shows, a careful examination of all of your picking buddies’ axes, and (let’s face it) the purchase of a lemon or two.

Excerpted from Acoustic Guitar magazine, October 1998, No. 70.