from guide: Guitar Wood Types and Tones

Alder

Guitar Body

Alder is light in weight with soft tight pores like Basswood. But there is a large swirling grain pattern to it with harder rings and sections. So imagine a Basswood type texture but with harder rings peppered throughout. That adds to the stiffness, and the complexity of the tones. It retains more of the highs that Basswood softens, but also gives some room to the lows. You have a broader spectrum of tones, which leads to the perception of a little less mids than Basswood.

Classic guitar bosy material. in some reasons less worthed by guitarists, than mahogany. Nowadays used by most brands, incl. Fender, BTW, Fender formerly used even as cheap wood as poplar, covered with ash or alder.

Used [as body material] in several American guitars like the Strat Plus, Clapton, and American Standard. Light weight (body weight about 4 lb.) with a full sound.

Moderate attack and smooth decay yielding an even balanced tone with well defined lows and clear highs. Good choice for guitarists that require the ability to cover a broad range of sounds with one guitar. (ie, Strats)
We get it from the Pacific Northwest. The prices are a little high and the quality is lower today.

Alder is used extensively for bodies because of its lighter weight (about four pounds for a Strat body) and its full sound. Its closed grain makes this wood easy to finish. Alder's natural color is a light tan, with little or no distinct grain lines. Alder has been the mainstay for Fender bodies for many years. It looks good with a sunburst and in solid colors. Because of its fine characteristics and lower price, Alder is our most popular wood. [As body material.]

Rich and full, strong in the lower midrange. This is probably one of the most widely used woods in the 60's for three single coil style guitars. It is medium to light in weight and takes well to sunbursts and some transparent colors. [As body material.]

Weight: 35
Grain: straight Figure: the wood ranges from a light cream to a pale reddish brown with no outstanding figure.
Texture: is smooth and fine
Properties: Alder is a flexible wood and easy to bend. It is stable and will hold its shape. A very good wood for carving and machining. It leaves a clean sharp edge and finishes to a smooth surface. It is an all around easy working wood.
Use: a prime use is for bent structural members and hull planking. Alder would make a nice deck. Well suited for framing and timbering. Nice for turning masts and spars. Suitable for quarter scale and larger carvings.
Production notes: Not much difference between factories, production.

Maple top on Alder body:

Takes Alder to a tone closer to solid Swamp Ash, but without the dynamics. The open resonance of the Alder comes through with the sharper attack and brightness of the Maple on the top end. The effect on the Alder is similar to the effect on Basswood. The upper mids of Maple come through, as Alder does not suppress upper mids.

Learn more about Woods, Body, Body Tops, Necks and Fretboards at guide: Guitar Wood Types and Tones