Touring the JL Audio Factory
throughout the enclosures. In addition to the strength improvement, these braces also help to break up resonances. We left the CNC-router area and headed over to the section where they assemble these enclosures. In an odd twist, they don’t even build these enclosures the “normal” way. Ordinarily you would cut the wood, assemble the enclosure and then cover it in carpet. Not JL Audio. Their engineers came up with a pretty unique way of assembling what they call “wrap sets.” A wrap set is a group of wood panels that are glued to a pre-cut piece of carpet with rigid backing. I watched as they built some of those MicroSubs. These enclosures are comprised of two wrap sets, braces and end pieces. In each of the channels cut by the CNC, they apply copious amounts of glue and place the other wood parts into those channels to wrap the enclosure. Each of the outer panels perfectly lines up inside the grooves and the glue holds together all of the interior panels and seals up any air gaps. It’s a great concept.
In-House Machine Shop On the way to the east end of the building (where the loudspeakers and home audio systems are assembled) we visited the JL Audio Machine Shop. As an engineering-based company, JL Audio has plenty of hands on-deck to try to solve any problems that may come up. This is not only evident in their products, but also in their assembly process. Steve said that in the early days, JL Audio relied upon external machine shops to build prototype parts for speakers and production lines. Sometimes the lead times for these items was weeks or months. As the company grew, they cut these lead times down by investing in their own in-house machine shop. Seems logical, but it comes at a pretty hefty cost—these machines are not cheap! I was able to sneak a peek and snapped a photo of the shop through the window on the door. I am not familiar with that level of machinery, but in layman’s terms, they had a bunch of big ones! I later saw racks and racks of parts that came from the machine shop being used in speaker production. These parts and many aspects
Many, many pieces are used to construct a microsub.
The wrap sets are glued together before heading to assembly.
of the production lines themselves were designed and built right there at JL Audio. The machine shop is a vital part of what they do.
Guillotines and Magnetizers Just outside of the home products assembly area and just before the loudspeaker production site, I visited an intriguing spot. Somewhat hidden by shelves full of speakers and subwoofers, I found a room with a contraption that resembled a medieval guillotine. Steve said it was where they brought people who shared secret photos. Okay, not really. It was actually a device they constructed to perform “drop tests” on various products. It looked like a combination of electrical and pneumatic contraptions that would raise and release a fixture that would hold a speaker. At the bottom was a “stop point” that would stop the fixture and exert enormous g-forces on the frame (and other parts) of the speaker. They would document the height and the
amount of g-force measured and track any failures they encountered. Sounds like the loudspeaker equivalent to a crash-test dummy. Once inside of the loudspeaker assembly area, Steve showed me where they work on motor assemblies (the magnet and its surrounding metal parts). A pallet of motors sat waiting next to a refrigerator-sized device with a strange chamber attached to it by a huge cable. The contraption turned out to be a magnetizer and the motors had not yet been charged. Steve showed me a tool called a “go/ no-go” gauge. It had a red band on one side and a green band on the other. On each end was a small rod. The rod on the green side was slightly smaller in diameter than the red side. This was used to make sure the gap (the area that the voice coil will hang inside the speaker) would be the proper size. If the green side fit in and could travel all the way around the gap, that meant it was good. They also check to make sure it isn’t too wide by attempting to put the red side in. It facebook.com/MobileElectronics 51
