
Ask the Expert: What can Torrefaction Do for Your Guitar?
Properly torrefied, properly selected wood used in conjunction with a well-engineered design, can produce guitars that are both great-sounding and durable.

Properly torrefied, properly selected wood used in conjunction with a well-engineered design, can produce guitars that are both great-sounding and durable.

If restoration is executed by craftsmen as skilled as those charged with maintaining Stradivaris, the spirit of the original guitar will eventually return after a bit of breaking in.
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Over the years, a number of blindfold test have been conducted, including a pair of widely reported tests administered by a trio of researchers in 2010 and 2012. In the first experiment, 21 contestants from the International Violin Competition of Indianapolis were asked to rate six violins: two Stradivaris, a Guarneri del Gesu, and three violins made by highly regarded contemporary luthiers.

By Dana Bourgeois |This article originally appeared in the April 2014 issue of Acoustic Guitar magazine and was reprinted in the September/October 2020 issue. Q: My 1983 Martin HD-28 has a buzzing or rattling high E string. The rest of the strings sound great.…

In general, lighter tops respond more efficiently to lighter playing styles, and more aggressive playing styles are required to bring out the full sonic potential of heavier tops.
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Q: What do you feel are the “right” areas to try to improve upon the classic styles? What areas of design must remain true to vintage originals in order to preserve integrity, and what areas have wiggle room for experimentation?…

The short answer is that I usually work closely with a variety of trusted tonewood suppliers to acquire woods that are sawn, matched, and cured specifically for making acoustic guitars. Typically, I try to inventory a six-month supply of most woods.

Q: Why is hot hide glue preferred by some luthiers, while others use synthetic glues, and what are its advantages and disadvantages? —Doug MacKenzie, Cary, North Carolina A: Hide glue, animal glue, and protein colloid glue are names for adhesives made…
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Numerous and complex elements contribute to breaking in an acoustic guitar, and it requires a lot of playing. But long long does it take to break in a new guitar?

Mounting a magnetic pickup on a prewar D-28 seems like an obvious no-no, now that the pickup is long gone, and prewar D-28s cost more than my first house. But what about installing a modern pickup on a Brazilian Santa Cruz?

Scale length can have a significant effect on playability. But what’s the difference between long-scale and short-scale guitars, and what are the advantages and disadvantages of each?
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Differences between riftsawn, quartersawn, and flatsawn wood can be significant. Stiffness-to-weight ratio, highest when boards are perfectly riftsawn, drops noticeably when a top is cut even slightly different. Velocity of sound—the ability to vibrate efficiently—corresponds closely with stiffness-to-weight ratio.

Q: My understanding is that a type of finish known as “French polishing” gives not only a hand-built look to an instrument, but also a better quality of tone and a fuller sound. How does this process work, and is…

To work efficiently, a guitar top must be built lightly enough to vibrate in complex ways.

The short answer is: sometimes. And the short explanation is that different models and different woods can have confusingly overlapping sonic qualities.
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Q: What exactly is the difference between a “handmade” and a “handcrafted” guitar? Furthermore, in the high-end market, what qualities should a player (not a collector) look for when evaluating the differences between, for example, a $3,500 guitar and a…

Perhaps because of their lighter weight, cedar and redwood tops tend to “open up,” or break in, relatively quickly. However, unless the builder pays adequate attention to longitudinal stability, cedar and redwood tops sometimes open up beyond a point that many players consider optimal, losing low-end definition as the guitar continues to be played.

It can be vexingly difficult to diagnose string buzz. Here’s a list of ten possible causes of a buzzing guitar.
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Traditional finishes, such as varnishes and nitro-cellulose lacquer, take many years or even decades to fully cure, while catalyzed finishes, like urethane and polyester, can cure in a matter of days.

In my view, the sound of a guitar is primarily attributable to its design and to the individual woods that it’s made from. Voicing is a process of optimizing the interaction between these two variables.

The luthier’s dirty little secret (drum roll . . . ) is that demand for ultra-fancy wood is greater than demand for wood that only sounds spectacular.
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Guitars sound best when string load and top resistance are in relative balance. An underloaded top cannot drive enough air to achieve optimum volume, power, and presence; an overloaded top is unable to generate higher overtones and lacks sustain. One key to optimizing the mechanical efficiency of an individual top is knowing, with some precision, how it wants to be loaded.

The best vintage guitars sound pretty dang amazing. On closer inspection, though, the picture can be more complicated.

Q: “I noticed that some guitars have very stiff backs and there is no difference to the sound whether the back is held against your body or away from it. What are the advantages of stiff vs. active backs?”—Seth Brockman,…
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Q: Using an electronic tuner, I can verify that when my open strings are in tune, my fretted octaves are accurate or nearly accurate. Individual notes of certain chords, however, can be very out of tune, and capoing in some…