Testing in-ceiling and in-wall speakers in open air without an enclosure will not allow them to produce their true sound quality. Most custom install speakers are open-backed and designed to utilise the installation cavity as an acoustic enclosure. Even the highest quality speakers will sound poor when tested in this way. Just like a traditional speaker with a cabinet, the air volume behind the drive unit is critical to its performance. A cavity that is very open (such as a ceiling void), or one which is very enclosed (perhaps full of foam insulation) will negatively impact performance, and most notably bass performance. Custom install speakers achieve their best performance in a specific air volume. This Goldilocks zone can be achieved by installing a fire/acoustic hood or back box behind the speaker. Generally fire hoods are the best solution in terms of cost and ease of installation, especially when retrofitting.