An Interview with the EMX Design Team

Built-in Compression Adds Live-sound Versatility to the new EMX-series Powered Mixers

New Features

What is the main difference compared to previous EMX-series mixers?

• The main difference is built-in compression. Compression is indispensable in almost all professional recording and live-sound applications, but we believe that this is the first time it has been built into an analog live mixer.
• Most "box type" mixers have no insert connectors, so there has really been no convenient way to use compression with them. As a result, many users of this type of powered mixer have never used compression, but we wanted them to have that option in the new EMX series.
• Although compression is used in most pro audio applications, it has been a bit too difficult for beginners to take full advantage of. That's why we've streamlined it down to the essentials and made it very easy to use.
• Another important new feature is FCL (Feedback Channel Location). This system detects feedback and shows you which channel is causing the problem. Some mixers from other manufacturers have indicators in the graphic equalizer section that show the feedback frequency, but indicating the problem channel allows the feedback to be more effectively controlled using channel EQ.
• If you try to control feedback using the EMX graphic equalizer, for example, you end up changing the sound of the entire program. For this reason it is far more effective to control it at the input, thus avoiding degradation of the overall sound.

The Battle Against Heat

Tell us about how you avoided heat problems in such compact enclosures.

• Heat and high power output unavoidably go handin- hand. In this case we were also determined to reduce weight, so the design, hardware, and mechanics teams joined forces to pursue this goal. Changing even a single component can alter the heat profile enough to require a change in heat sink design, and that change can cause a change in sound quality, so the design process involves a lot of trial and error.
• In this particular case, the fact that we were able to use internal heat-flow simulation and analysis was a huge advantage. We were able to define an enclosure shape on the computer, and then by analyzing the heat flow while refining the heat sink configuration we were able to come to within 80% or 90% of the ideal final design. The final stages using physical prototypes still relied on trial and error.
• In the box-type 212C, 312SC, and 512SC, it was easy to mount the fan away from the circuit board to minimize degradation of the audio signal. But in the console-type EMX5016CF finding the ideal fan location was extremely difficult. Since the fan must be located near the input circuitry, special measures have been taken to ensure that electronic and mechanical noise from the fan do not affect sound quality, while at the same time ensuring maximum heat extraction.
• The hardware team wanted to increase the size of the body by 30 millimeters, but our goals for a streamlined, compact design were important enough that we decided to find other ways to achieve the desired performance.

Reliability Without Compromising Performancet

The simplicity and aesthetic appeal of the designs are quite impressive. Tell us about the design concept.

• Simplicity was the main goal, particularly in the console-type 5016CF. We wanted to consolidate the mixer controls, so the utility control section has been clearly separated. We didn't even want any handles to be visible.
• An important idea implemented in the box-type models is that they can be set at an angle like monitor speakers. The integral handles are also an important design feature, and achieving the required strength was a constant problem.
• Achieving the ideal blend of size, weight, and durability is quite difficult. As usual, demands from the sales team continue to escalate while the hardware and mechanics teams try to turn them into reality . without ever reducing or compromising features or performance. Computer simulation was called into play once again, providing an accurate preview of the mold-flow characteristics of the resin used for the box-type housings.

• The final strength of the molded housings depends to a large degree on how the molten resin is introduced in the mold, and how it flows within the mold.

• The strength of the integral handles was also predicted using computer simulation, and as a result, we have achieved strength comparable to that of aluminum.

Achieving Pure Sound Quality

What measures have been taken to ensure optimum sound quality?

• Of course sound quality is first and foremost in the design of any model. Achieving the lowest possible noise and hum when changing components is always a challenge. There's influence from vibration, from the current flowing through the components themselves, and a simple op-amp IC change can precipitate a large change in sound. We often find ourselves using the best components we can find rather than compromise on sound quality. Even the FCL system has an effect on the sound, and we were able to achieve a dramatic improvement by simply eliminating a single component from the circuit. Once again, the final design depends on trial-and-error listening tests while changing components.
• With SPX effects in all models in this EMX series, plus compression and FCL, you can rely on a single EMX powered mixer to deliver outstanding live sound, especially in applications that use mostly microphones.

Most compressors have at least two controls, what is the idea behind having just one?

• Simplicity. Standard compression controls can be very difficult to set quickly and accurately, but we?ve managed to provide well-balanced threshold and ratio settings that can be controlled by a single knob. By focusing primarily on microphone applications in which compression is applied to vocals, acoustic guitar, or similar sources, greatsounding compression can be dialed in quickly and easily.
• There's a good description of compression and its uses in the owner's manual. We hope that our users will take advantage of this very useful feature.

P.T. Yamaha Music manufacturing Asia
-Manufacturing the electronic instruments and PA products

From the initial design to final manufacturing, all production processes for the Yamaha EMX series Powered Mixers are performed entirely inside the company. Moreover, every product that comes off our production line must pass strict quality controls using the sophisticated test instruments. Thus, all of this enables us to deliver the highest quality products to you.