Buying guides · 6 min read

How to choose a double bass

Choosing a double bass means settling three things: body size, how the top and back are made, and who sets it up. A practical guide from a working player.

2026-05-19

Three quarter is the normal size

Double bass sizing is misleading, because the fractions do not describe a fraction of anything. A 3/4 bass is the standard adult instrument and what almost every orchestral and jazz player uses, with a string length around 104 to 106 centimetres. A 7/8 is noticeably larger, closer to 110, and a full 4/4 is rare outside specialist solo work and some older German instruments.

The reason 3/4 dominates is the left hand. On a bass you cover a whole tone with four fingers across a stretch already at the edge of what a hand can do comfortably. Add three centimetres of string length and that becomes a genuine strain, particularly in the lower positions where the intervals are widest. Players with large hands sometimes prefer 7/8 for the extra depth and volume, but that is a choice made from strength, not a default.

Smaller fractions exist for students: 1/2, 1/4, and 1/8 basses with proportionally shorter string lengths. A child should be on one. The test is simple: standing behind the instrument, can they reach first position without their shoulder rising and can they get the bow to the bridge without leaning? If not, the bass is too big.

Plywood, hybrid, carved

Basses are built three ways, and the difference is in how the top and back are made. A plywood bass has laminated top, back and ribs, pressed into shape. It is tough, tolerates humidity swings well, and survives airports and clubs. The tone is more focused and less complex than a carved instrument, which many jazz players regard as a feature rather than a flaw, because it amplifies cleanly and does not feed back as easily.

A hybrid has a carved solid spruce top with laminated back and ribs. The top does most of the acoustic work, so a hybrid gives much of the tonal gain of a carved instrument at a fraction of the cost while keeping the back and ribs stable. For students moving past a first instrument, and for jazz players wanting warmth without fragility, hybrids are often the sensible answer.

A fully carved bass has top, back and ribs all cut from solid wood, usually spruce over maple. It projects better, has more colour in the sound, and responds more sensitively to the bow. It is also more vulnerable: seams open, cracks happen, and it needs a stable environment. This is what orchestral players use, and it is what you buy when tone is the priority and you can look after the thing.

Setup matters more than the label

A double bass arrives from the factory unfinished in an important sense. The bridge is a blank, the nut may be cut roughly, the fingerboard has not been planed true, and the soundpost is wherever it landed. A bass with mediocre wood and an excellent setup will play better and often sound better than a superior instrument left as it came.

The work means cutting and fitting the bridge to the exact curve of the top, setting string heights so the strings press down without a fight but do not buzz, planing the fingerboard for a slight scoop and no dead spots, fitting the soundpost, and checking the nut slots.

Budget for this separately and assume it is not optional on anything cheap. Ask whoever is selling the instrument whether a luthier has set it up, and if the answer is vague, assume nobody has. Strings are part of the same conversation: a set costs real money, and the difference between gut, steel orchestral and steel jazz strings changes the instrument's character more than most buyers expect.

Budget tiers, honestly

At the entry level you are looking at plywood student instruments, often sold as an outfit with a bag and a bow. These are fine for a beginner and genuinely useful for school and community orchestras. Expect the included bow to be barely serviceable and plan to replace it early; a decent bow transforms how a modest bass responds.

The middle tier is hybrids and the better plywood instruments from established workshops, where the setup is competent out of the box and the fittings are ebony rather than stained hardwood. This is where a serious student or a working jazz player can settle for a long time.

Above that, carved instruments start at several times the cost of a hybrid and run upward without an obvious ceiling, into old European instruments where provenance and repair history set the price as much as sound does. Old basses are not automatically better. A well-made new carved bass often outplays a tired hundred-year-old one that has been patched repeatedly.

How to try one

Play open strings first, slowly, with the bow. Listen for whether each string speaks immediately and whether the volume is even across all four. Then play the same note in different positions on different strings and listen for wolf notes, that strangled stuttering that happens when a body resonance fights the string. Every bass has some. The question is how bad and how badly placed.

Sight along the neck for a twist. Tap gently around the seams and edges, listening for the hollow buzz of an open seam. Look inside with a torch for cracks and old repairs, and check the soundpost stands upright rather than leaning.

Finally, play something you know well, in the register you actually use. A bass that sounds glorious on low open E may be dull in thumb position, and if you spend your life up there that matters. If you are in Singapore and want another pair of ears on a candidate instrument, that is a normal thing to ask a teacher for.

Frequently asked

Is a plywood bass bad?

No. A plywood bass is the right choice for a lot of working situations: touring, teaching, outdoor gigs, and any room where humidity swings. It resists cracks and open seams far better than carved wood. You give up tonal complexity, but plenty of respected jazz players have used laminated instruments their whole careers.

What size double bass does an adult need?

Three quarter, in almost all cases, with a string length of roughly 104 to 106 centimetres. Seven eighths is an option for players with large hands and enough strength, and gives more depth and volume. Four quarter instruments are rare and mostly historical. Children need half, quarter or eighth size depending on height.

How much should I spend on setup?

Treat it as a real line item, not an afterthought. Bridge fitting, fingerboard planing, string height adjustment and soundpost setting are skilled work, and on an inexpensive instrument the setup can reasonably cost a noticeable fraction of the purchase price. It is the single change that makes the biggest difference to how a bass plays.


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A&G Academy teaches accordion, bayan and double bass, and sells the instruments we teach on. Ask us anything — we'd rather talk you out of the wrong instrument than sell you one.

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