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6-1/2" versus 6-3/4" car speakers

A case of car compatibility

Buck Pomerantz was born and raised in Philadelphia. His parents bought their first television set when he was born. He figured out how to run it by the time he was two. Besides athletics, his formative interests included electronics, amateur radio, music, and stage crew work. He got his BA in writing from Brown University. Then he joined a rock 'n roll band as their soundman and moved to Charlottesville, Virginia. After that venture failed, he spent time in Boston, New Orleans, and Berkeley. He worked in a music store in Austin manufacturing, installing, repairing, and operating sound systems for recording studios, clubs, and bands. He moved back to Charlottesville, ran a little recording studio and finally joined Crutchfield as a copywriter. He has 2 grown children and 3 grandchildren, but after a good nap he can still rock out.

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Many customers note that sometimes Crutchfield's classification of a car speaker's size is different from what the speaker manufacturer states. This is especially true in the case of 6-1/2" versus 6-3/4" round speakers. What's going on when a company says that their speaker is 6-1/2" and Crutchfield says it's 6-3/4"?

Patrick, a Crutchfield Product Research Specialist says: "As for the [speaker] manufacturers; they typically name the speaker based on some measurement of the speaker itself. We look at speakers from the vehicle side and classify them based on easily fitting into standard vehicle applications."

Crutchfield installer

In other words, when we say a speaker is a certain size we mean that without modifications, it fits the cutout hole and bolt pattern for that classification. We go by what size holes the car manufacturers stamp and drill in their frames and brackets to ensure our customers' purchases fit.

In order for us to call a speaker a 6-1/2", we have to see whether or not it fits into a cutout hole with a diameter between 4.8" and 5.2". Auto manufacturers call this a 6-1/2" speaker, and so does Crutchfield. Speakers classified as 6-3/4" have to fit in a 5.2" to 5.7" cutout. Many speakers come with adapter brackets that allow them to be installed into different-sized holes with various bolt patterns. That's how a 6-3/4" speaker can also fit into a 6-1/2" space, and vice versa. When we list a speaker as fitting both 6-1/2" and 6-3/4" locations, it usually fits one size exactly out of the box, and is packaged with an adapter bracket to fit the other.

We hope this clears away some of the confusion between what size speaker manufacturers say they've built and what Crutchfield says will fit. We constantly research the products we sell, so that the information we give our customers will be as accurate and up to date as possible.

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