The three most important attributes of any professional audio product? Reliability, reliability and reliability. Toshihiro Inoue tells Gez Kahan about Yamaha’s Quality Management System
There are no second chances for the audio professional. You’re relied on to make the show happen, which means you have to have complete confidence in your equipment. And that puts reliability pretty much top of the wish list when it comes to designing a new product – because all the bells and whistles in the world won’t bail you out if it falls over in the middle of a gig.
Yamaha’s commitment to reliability is not simply a matter of the company setting rigorous production standards and keeping to them (although of course it does). Ensuring reliability starts right back at the R&D stage, and it goes way beyond shipping. Nor is it simply an internal process. Yamaha has implemented a strict, externally monitored, quality control programme tied to ISO9001:2000, an internationally recognized world standard for quality in manufacture.
“Our Quality Management System covers all our activities from product planning to development, production, and even to sales,” explains Toshihiro Inoue, Manager of the Customer Satisfaction Planning Group for the division which produces Yamaha’s Commercial Audio products. “ISO9001 sets out a framework, which we have customized to meet the special needs of professional audio products. In most areas the standards we set ourselves will exceed even the stringent ISO criteria. And everyone in the organization has to follow the same Quality Manual.”
To check that those standards are being upheld, independent supervisors from DNV (Det Norske Veritas), a Norwegian certification company, spend time each year on site to audit the entire process. “This doesn’t apply only to our Japanese factory,” says Inoue. “They also audit our facilities elsewhere in the world such as Indonesia and China to ensure they all operate the same quality policy and all meet the same high requirements.”
The procedure is strictly enforced. “We have six stages in the product development process,” he explains, “and what has to be done in each stage is strictly set and standardized. You cannot move on to the following stage, unless all requirements in each stage are fulfilled.” That means that even before a product moves into production it will have demonstrated that it meets both safety and reliability standards.
Safety standards – such as IEC, BS, CEE, EMC (EMI & EMS), and RoHS – are a matter of law, and products have to comply to be sold in the territories covered. That compliance requires specialist equipment and purpose-built facilities where the testing takes place – and it doesn’t come cheap. When Japan’s digital TV service kicked off and its radio output swamped the remote mountain area the company had been using for testing emissions, Yamaha had to kit out new studios at its Hamamatsu headquarters. The cost of screening the main studio to avoid any extraneous radio noise, and fitting it with absorbent materials (similar to an anechoic chamber) to guarantee a ‘clean’ reading, comfortably exceeded 200 million yen ($2m).
Safety is a given, but reliability is what customers really care about. They need to know that the 5,001st time they press a switch, turn a pot or ride a fader it’s going to work just as well as it did the previous 5,000 times. Before a component makes it on to the spec sheet the design team will have held a ‘beauty contest’ to select suitable candidates. Then, while still in the pre-production stage, they test them well beyond any expected usage – volume knobs, for instance, are put through 100,000 turns on an automatic machine, then examined to ensure they still work like new. Then, and only then, can an order be placed with a supplier.
The same rigour is applied at the production stage itself. A component measuring machine at goods inwards checks that samples from every incoming batch are accurate to 1/100th of a millimetre, while chassis parts are laid up against a template to ensure that all screw holes are in the right place. Where appropriate, suppliers also provide samples, prepared as part of the batch, for ‘destructive’ testing: a hard pencil is used to check that the paint finish is resistant to marking or chipping, for example; a sticky tape test checks that screen printing won’t lift.
Sadly, Inoue admits, however much care is lavished on the products in the factory, there is no guarantee that that movers and shippers will be so gentle. So at prototype stage the quality team packages them up, drops them, bumps them, and shakes them for hours at a time on a special vibration machine that mimics the effect of carriage by road, rail, sea and air – and then unwraps them and tests that they’re still working flawlessly. And, he adds, it’s not only machines that check them – the listening test is always done by real people.
Occasional problems will still crop up, of course – which is why Yamaha’s Quality Management System goes beyond planning, development and production to encompass sales and after-sales. “We have a system called the Overseas Product Quality Report, which the service manager of each subsidiary has to send in,” Inoue explains. “Through this we gather information on any quality problems from all over the world. There are two purposes: to solve any problem as quickly as possible, and to feed information back to the development or manufacturing teams to ensure it doesn’t happen again.”
Toshihiro Inoue and his team have to accept that they won’t always be popular with the development engineers. “Sometimes an engineer brings in a product and we have to say ‘No’. It’s hard, because we have set very high internal quality standards, much stricter than the normal internationally respected standards and those standards can be difficult for the engineers to meet. But if anything doesn’t meet the criteria we set, we do say ‘No’ – it’s not only our duty but our entire raison-d’être.”
And, as he says, if a development engineer has a bad day because he has to go back to the drawing board, that’s a pity. But it’s not a calamity, like an audio engineer having to tell his client that the show can’t go on.
