Rare Facility Tour of a Chinese Speaker Build House

Filed under: Car Audio



Nick Lemons of Stereo Integrity recently took a trip to China to check on his newest subwoofer creations. While over there he snapped some pictures for us and a did a write-up on his experiences. This is a pretty rare look into an overseas build house and extremely interesting.


Written by Nick Lemons:
As many of you know, we (Stereo Integrity) are having our subwoofers built overseas. If you didn't know that before, now you do. Now, I know what you might be thinking - Oh crap! China?! Well there goes the quality! As true as that has been in the past, it's not always the case these days. Saying that everything from China is cheap and of poor quality is just like saying that everything built in the US is grossly overpriced. You can get extremely high quality parts and/or products from China... if you know who to use.

I took a trip over to China to make sure that everything was going as planned and to also do a little more product development while I was there. Not many people have seen the build houses over there, so this write-up was done to give you guys an insight into the Chinese build houses.

First off, we are going to explore just one of the multiple build houses that my company uses to build our new Mag and BM subwoofers. The build house I'm about to show you is gigantic! Think of the how big the Pentagon is, and then think bigger. I took as many pictures as I could, but unfortunately I couldn't take pictures of everything. I'll do my best to explain it all though.



When you step on campus the first thing you'll say is "Holy Shit" because of the sheer size of the buildings. The campus is literally a campus too - some of the workers live above the shops, they have a cafeteria, and everything else a small city would have.

You are first shown the sample room (no pictures are allowed). The sample room has every basket, cone, surround, and spider you can possibly imagine. It is so many parts it's overwhelming. We're talking hundreds and hundreds of baskets from 40mm (1.6 inch) diameter all the way up to 450mm (18 inch) baskets in every color and finish you can possibly imagine. There are cones everywhere dressed in black, red, yellow, blue, shiny, satin, tie die (yes, I'm serious), sand, chrome, plastic, poly, etc. Surrounds are the same way - foam, rubber, double roll foam, double roll rubber, inverted foam, inverted rubber, and any/all color variations you can possibly fathom. The sample room reminds you of a small library, except the bookcases are display cases for speaker parts. Walking through their sample room is a speaker-buff's wet dream. I've seen a lot of baskets, cones, spiders, surrounds, etc, before entering that room, but after I left that room I realized just how much I had not seen. If you can dream it up, you can piece it together in that sample room.



Moving on, the manufacturing facilities are HUGE! There are about 8 buildings that are the size of a football field and each building is six stories tall. It's truly amazing. What gets even more impressive is there are more buildings behind the big buildings - each about 3 stories tall. Inside each of these buildings are the facilities to make cones, baskets, surrounds, motors, and everything else. Seeing a cone being made would probably let a lot of people down because there's very little glamour in it. But behind the each cone made is a worker dipping a strainer (the number of dips determines the thickness of the cone) into the slurry mix and then putting the mix into the forming machine that heats, presses, and vacuums the mix. In other buildings T-yokes are being made by huge presses. The presses range from 500 tons to 1,500 tons. Small mushrooms of steel are placed into the presses where the steel is pressed into the final t-yoke shape. A single t-yoke is made every 2 seconds at the facility. Thirty machines can run for 20 hours a day producing a t-yoke every 2 seconds. That's the capability to produce over 1 million t-yokes in a single day.





Other buildings are sources for surround manufacturing, trim ring manufacturing, magnet boot manufacturing, basket manufacturing (both stamped and cast), and anything else you can think of related to speakers. My favorite building was the one where baskets are made. Not just to watch the molds being toted around by huge steel I-beam lifts, but to watch how baskets are cast. Raw molten aluminum is poured into castings where the metal cools and forms the basket shape. The mold is then opened to reveal a raw, un-molested, basket that is then placed into a big bin. The bins are later taken over to a different part of the building where 20-30 employees are working non-stop de-burring baskets all day long. The excess aluminum that is left over after the molds are done is swept up and re-used for other baskets where the purity of the aluminum isn't as critical as others. It's amazing to watch a facility like this in action because absolutely nothing gets wasted. Spare aluminum, rubber, paper, all of it is re-used and nothing goes to waste.



And then there's another facility that we use to assemble the speakers. That's right, just assembly. They assemble, test, and package every single speaker. The most important part of that last sentence was that they test every single speaker. Hundreds of thousands of speakers are put together and hand-tested to ensure they are in perfect working condition. If the speaker doesn't pass the test, it's scrapped.



The level of detail that can be accomplished in facilities like this is astounding. If you know what you're doing right down to the very last detail you can get anything accomplished. While visiting the build houses over in China, we covered everything from the color, thickness, and style of paint on the basket to the voice coil lead wires and how they were soldered, how much and how long the braiding was loose, how often the wire was stitched on top of the spider, size and number of rolls are on the spider, etc. Every last detail was covered.

And for those of you who still think that your subwoofer was made in the USA because it has a sticker on the box, you might not rest as easy knowing that more-than-likely all the parts (the motor, basket, and soft parts) came from Asia. All 12-spoke baskets come from China and almost all motors are made in China. Same with spiders, voice coils, voice coil leads, etc. Some subwoofers might be put together in the USA, but 99% of the time the parts come from China. But even then, being put together in the US doesn't mean they were put together well. And if your parts come from China, there are varying degrees of quality. Some are excellent and some are poor. Like I said in the beginning of this article, the same thing applies no matter where your parts are made. Quality, durability, and precision are things you always have to verify.



My company has gone through over 7 build houses world-wide and none of them even start to come close to the quality and attention to detail that can be achieved with the team of build houses we are using now. We've been looking for a build house that could do anything we wanted for over 8 years now. We didn't find just one - we found several, and when their talents are combined they can accomplish exactly what we desire.

China is a phenomenal place. It's not the communist, police-ridden, rude country that the US media makes it out to be. The people in China are extremely nice, they love American culture and it's more capitalist than anything else. I saw maybe 2 police cars the whole time while I was there and felt safe the entire time. If you ever get the chance to take a trip to China, don't hesitate to go.