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Selecting Subwoofers for Dubstep and Drum and Bass

As a concert producer, I’m frequently asked which subs I would recommend. Subwoofers, like mains, are selected by the type of music you will be playing though them, and how they are going to be used. For the purposes of this article, I’m going to restrict the conversation to just Dubstep, and Drum and Bass.

Dubstep and Drum and Bass have a huge amount of content in the 20hz – 50hz range, and if you do the math, you are going to need about 5000 watts dedicated to a that frequency range to produce enough of that sound to be heard along with the rest of the music.

My setup

My larger setup is (5) QSC HPR181s across the front of the stage, (6) Martin Blackline dual 18′s for the house, and 2 Bag End Dual 18′s running 8000watts through an ELF processor dedicated to the 8hz – 50hz range through a lab gruppen amp. When I play smaller shows, I just use my QSC HPR181, which are 700 watts each, but good for ultra high volume bass. The QSC’s are self powered and take all of 5 minutes to setup, which also helps. Now I’ve heard the common wisdom, don’t mix subwoofers, but in reality, I’ve yet to find one sound manufacturing company that does it all, short of a tour package that is produced for a given show, rather than a type of music (an important distinction). That said, crossover points and keeping each subwoofer and the overall system in phase is very important when mixing subs.

Setting the crossover

Conventional crossovers, like the very common dBx DriveRack PA have a good and fairly adjustable crossover that also includes the ability to change the slope of the roll off. When matching and tuning subwoofer frequencies, I’ve noticed that although the crossover claims to have rolled a frequency off, some of the content continues to be transmitted to the sub. Clearly, when two brands of subwoofers are generating the same tones, distortion is created. I, therefore, separate the frequencies by about 5hz. Visually on the crossover, it appears that I’m losing musical content, however, with the amplification gain, in fact I’m not, and a RTA mic will confirm that the setting are correct.

Sealed box enclosures and subharmonics

Bag End is really the go to here. There are other sub systems that do subharmonics, but Bag End was first, so I’m writing about them. The Infra processor, and before Ron Wickersham left, the Elf Processor are the two key components. Dubstep and Drum and Bass require a huge presence in the 20hz – 50hz range. Most people cannot hear music in this range, but you can feel it, and you can feel the difference between 20hz and 40 hz when the signal is clear and free of clipping. The Infra processor is available in two forms. The first one has a flat response down to 18hz, the second one to 8hz. 18hz is much more efficient for larger systems. If you have an extra 20k to burn, then go for the 8hz integrator and (4) dual 18′s. You will need a substantial amount of AC Power to run the amps as well, usually an additional 20amp 220 circuit for a Lab Gruppen or four 20amp 110 ciruits for four QSC amps bridged into each sub. My Bag Ends generally pull about 3000 watts per dual 18 when generating content STRICTLY LIMITED to the 18hz – 50hz range. I should note that making adjustments to your crossover at full volume can quickly destroy all of your equipment, so be careful, and know your equipment frequency response and power handling ratings.

Pricing

Subs vary tremendously in price. In the lower price range, I have heard the Peavey blackwidows, which are technically louder, but much less musical. When you are mashing up two tracks, or quickly transitioning from one to another, it is tough to hear much difference with the Peavey subs, they are just loud, not so much musical. JBL and Cerwin Vega subs are fart cans, and I think most people know this. They can rumble and shake, but they don’t have an articulated sound – a clarity in the low end that is absolutely necessary for Dubstep and more so for Drum and Bass.

Some other equipment that I’ve tried, If you are rich, the D&B (not db technologies) audioteknic Q2 subs are killer, EAW 218z subs are pretty good, McCauley does a pretty decent sub with good all around specs for Dubstep, and Bag End kills. All of these cabinets require extremely expensive amplification though. You can get 12,000 into amps alone before you can even turn on a mid-sized system of this caliber.

Home Construction

Another alternative, is to build your own box. This is not a beginner project, but if you love wood working, and have a spare 2500 bucks, you can build some pretty amazing cabinets. The best way to do this is to get on the forums and look at designs, then read the threads through. Often people post reviews over the course of years.

Look for a design that has a good frequency response down to 40hz, and a driver that has exceptional frequency response. OHM (brand) makes a pretty incredible driver, and there are a couple of high end RCF subs that are bad to the bone.

Listen to them before you buy them if at all possible though, using a parametric EQ and shut off all frequencies except for the 20hz to 50hz range – that is the sweet spot of Dubstep that makes it truly different from other similar music.

Why Is Food Packaging Important?

Food easily goes bad if it is not properly stored and preserved. Bad food may cause health problems or serious diseases. People have many practical simple methods of protecting food from being spoiled. High-end technologies are developed to prolong edibility of food and advanced equipment is designed for the purpose of long-distance transport. For instance, people cure food with salt or sugar, air dry it under indoor temperatures, or put it in refrigerators so as to keep its freshness and edibility. In spite of the diversity of preservation methods, techniques and equipment, the core idea behind is to preventing fungi, bacteria, or other microorganisms from growing in the food. Food packaging is one of the most cost effective preservation methods and serves as a basis for customers to protect food for an even longer time.

Food manufacturers pack their products in a pretty manner, with an aim to promote them in a broader region so that more people will buy the products. For the manufacturers, food packaging means more profits. They do their best to improve package design, adding additional value to manufactured food. To ship food abroad, manufacturers also need to pack food with caution, preventing physical damage to or chemical change of food in the process of long-distance transport.

Packed food in stores looks appetizing if the package design is pleasant to eye in color and picture. A good package design not only serves to maintain food shape and quality but also arouse customers’ desire to buy them. More often than not, prospective consumers are convinced of buying a product mainly because of the attractive design. Labels on packages contain information about the food inside, telling people what it is made from, how to cook or eat it, when and where it is produced, as well as some precautions. In the event of a food poisoning accident, label information helps people find the food supplier as soon as possible.

Food is packed all the way to be enjoyed by consumers. Thanks to food packaging, seasonality of food is no longer a problem for people who would like to taste summer fruits in winter. Also, people may enjoy fresh green vegetables even though they are not locally grown. Packages for liquid food are designed with straws or other assistant tools to facilitate people drinking. Power-typed and grain-like food is contained in bags, cans and boxes for transport requirements. A wine with a pretty package is a good option for people to give as a gift between friends. Such a gift makes you look decent and shows your cherishment of your friendship.

With the continuous development of modern society, food packaging is endowed with many additional purposes. It is not simply a preservation method any longer. It serves to create profits for food producers, attract more consumers, and even as a bridge of friendship.

The Different Types of Loading Dock Equipment

Loading dock equipment is used for the easy and safe loading, unloading, and movement of material at docks. There are different types of loading dock equipment. Here is the brief description of some of them.

Dock Levelers

Dock levelers are used to allow easy transfer of goods from the docks to the trailers. They create a bridge between the dock and the trailer thus ensuring easy and safe movement of material. Depending upon their drive mechanism, dock levelers are of three types – mechanical, hydraulic, and pneumatic. Mechanical levelers are the least expensive. In this type of leveler, the spring and chain action causes the deck to move up and down. The docks that handle large volume of material generally use hydraulic levelers. This type of leveler is automatic and gets activated with a push button. Pneumatic levelers use air bags to move the deck up. These are gaining popularity because of their simple and easy operation and low maintenance.

Another type of dock leveler which is extensively used in climate controlled ones is vertical dock levelers. These are hydraulic levelers that remain vertical when not in use. It helps them to maintain cleanliness and improve their energy efficiency.

While choosing one leveler, one should keep in mind the volume of material handles, the load that the leveler should be able to carry, and the height adjustment.

Vehicle Restraint

Another dock loading equipment is vehicle restraint. This equipment is used to enhance the safety at the dock. Since the accidental movement of truck during loading, unloading or parking at it can cause mishaps, vehicle restraints are used to keep them in place. One can use mechanical, Electro-mechanical or Electro-hydraulic vehicle restraint in their facility. While selecting this loading the equipment, one should ensure that it is user friendly.

Dock Seals

This loading equipment is used to fill the gaps between the trailer and the dock door. This helps to prevent the leakage of air, which is the major cause of loss of energy at them. Also, it improves the safety of material and helps prevent contamination of the stored material, which could occur due to air infiltration. There are different types of dock seals. Among them, inflatable seals are the most widely used. They seal both the sides and top of the trailer. Pad seal is another popular dock seal. It is popular because of its low cost.

Besides the above, there are several other types of loading equipment which includes lights, bumpers, doors, lifts and so on. There are several things that one should consider while buying loading dock equipment. Some of them are reputation of the manufacturer, cost of the equipment, specifications of the equipment, and its safety features. One should only trust a reputed dock loading equipment company for buying such equipment. The most important specifications that should be checked are the weight bearing capacity and size of the equipment. Also, one should pay attention to the material of construction of the equipment.