Yamaha’s ISO:9001-compliant product design process leaves nothing to chance, with set procedures every step of the way. But, as Gez Kahan discovers, there’s also plenty of scope for innovation and flair
When you think of product design, what springs to mind? Is it a block diagram and a mass of wiring, or reams of software code and a handful of silicon chips? Is it a hard-wired prototype sitting on a test bench, or a computer screen glowing with the sleek contours of a virtual realization? Or perhaps it’s a research and development meeting discussing how best to fulfil a market need, or a marketing team planning the launch campaign. The fact is, modern product design is made up of all those and more, along with a bewildering number of other issues that have to be taken into account – regulations and safety standards, environmental concerns, ease of assembly, and, not least, affordability.
Getting the right balance of those elements when designing mixing consoles requires efficiency, discipline and a methodical approach, explains Seiichi Miyawaki, General Manager of Yamaha’s Commercial Audio Business Unit, and indeed Yamaha’s methodology is accredited by the International Standards Organization. But as any chef knows, following a recipe is only part of the story. You also have to have experience, flair… and the best – and purest – ingredients.
Individual components matter. Take capacitors, for instance. It’s not enough just to decide on a specification and look around for the cheapest deal, because supplies from different manufacturers might seem identical but can turn out to have minute differences in performance that will be amplified at the output stage and risk coloring the sound. “Even the thickness of the connecting pins can make a difference,” says Miyawaki. So, at an early stage in the development cycle, Yamaha’s hardware engineering team holds a beauty contest to choose the perfect components for each new product.
Experience counts when selecting materials too. With users craving ever-lighter products, inexperienced engineers might be tempted to experiment with super-lightweight alloys for the heat sink, for example. But Yamaha’s Hardware Group engineers point out that the shape of a heat sink is more important than the material – and anyway, lighter metals tend to be prone to vibration.
A lot of time is also spent on circuit design itself (a beautiful circuit pattern makes a beautiful sound, is how Miyawaki puts it) and particular attention is paid to the analog circuitry because though the desk may be digital, not everything that plugs into it will be – and the human ear, which is the ultimate judge of quality, remains stubbornly analog. But digital technology has a big part to play, not just in the internal workings but in the design of the product itself.
Innovation always involves trial and error and that can be a costly business. And though anyone in product development knows that money spent on R&D is money saved many times over at the production stage, it makes sense to minimize the potential for error before building expensive prototypes. To do that, Yamaha has invested in a Virtual Design Review simulation system, which models the behaviour not just of circuits but of individual components at the pre-prototyping stage. It’s not a cheap option – companies using this kind of software are more often found in the aeronautical and motor industries than in professional audio – but it pays dividends in the longer term. In fact, evaluation using Virtual Design Review software is a continual part of the design process, where it can predict likely areas of concern such as excessive heat generation from components or analyze the ability of carrying handles and the internal supporting structures to withstand strain.
Use of the technique has enabled the mechanical engineering team to propose a modification to an internal bracing plate so that it now acts as a heat shield as well suppressing vibration, for example. And reconfiguring the way the harness is connected to the power supply has vastly reduced the potential for interference while making for a more elegant design, with the spin-off benefit that it is also easier to assemble at the production stage. Such design improvements also become standard practice for future projects.
While software simulation isn’t a complete replacement for physical modeling, it’s accurate enough to mean Yamaha now needs just one traditional prototyping stage, instead of two. And that, quite apart from the Virtual Design Review’s value in anticipating potential snags, produces two benefits for the customer: it helps Yamaha keep costs down, and it reduces the length of the product development cycle.
Software emulation has come into its own not just for evaluation but as an essential for audio processing, with DSP software an accepted replacement for hardware units at all stages of the signal path. And its use is already evolving at a deeper level. Yamaha’s DSP guru, Toshi Kunimoto, and his Technical Development Group have taken their Virtual Circuit Modeling technology right to the heart of the process by using software not just to replicate hardware effects and the like but to provide software solutions at component level.
Even where software does not fully replace hardware, it can be used to improve performance. For instance, individual motorized faders will have minute differences in response. Software can monitor and analyze those differences and make the microscopic adjustments that will eliminate any inaccuracies, perfectly matching each fader’s responsiveness with that of its neighbouring channels.
And – just as with the hardware development process – there’s a constant review to fix any bugs, and ensure rock solid reliability at every stage from operating system to user interface. Software bugs are defined as major, minor, rare or ‘unusual usage’, and measured by incidence (detected bugs per hour) under a comprehensive software development management system.
But not every upgrade is a bug fix. User feedback both from top-flight sound engineers and from more than 6,000 “ordinary users” worldwide also supplies the teams (hardware as well as software-related) with a wish list of new features and improvements they’d like to see. A case in point is a software update for the DME64N that enabled its Event Scheduler to take account of clock changes due to daylight saving – daylight saving measures being routine in Europe and most of North America, but generally not being adopted by most Asian countries.
In the end what matters with any piece of audio equipment is how it sounds. “Transparency of sound is what engineers require,” says Miyawaki, but that is down, not to a machine, but to the highly trained ears of the development team. “When it comes to ‘Sound Character Design’, there is no useful tool – besides the human ear – to help with development,” he adds.
There are other areas where the computer is no match for human design flair and experience – such as interface design where the guiding principles rely less on hard and fast rules than an appeal to the senses and an intuitive appreciation of the user’s needs. And even when all the separate centres of expertise have combined to design the perfect prototype, the majority of the production processes and testing are undertaken not, as you might imagine, by robots but by real people. Which, after all, is who the products are designed for.