History of the first quiet ECHO leaf blower

In 1994, I was hired by ECHO Inc. to head up their Engineering Department, which at the time was a small group of capable technicians and engineers that made changes and improvements to existing products. The bulk of the design of new products was handled by our parent company, Kioritz Corporation, located in Ome, a suburb of Tokyo, Japan. Kioritz and by default Echo had a fine reputation for quality, making several different professional products that utilized their mainstay two stroke engine. Among these were leaf blowers.

One day while I was talking with our Vice President of Marketing and Sales about the current state of leaf blowers in the marketplace, I discovered that there was a movement, primarily in California, that was attempting to convince cities that leaf blowers were too noisy and should be banned. To be honest, at that time, they were quite difficult to listen to at close range. Even at some distance, one could tell if it was a leaf blower over a lawn mower, for example, because most of them had a telltale whistle or scream emanating from the primary blower fan. People claimed that blowers were too loud, but the real problem was that they were irritating due to the high pitched sound they generated.

We decided that we needed to develop a quiet version for those communities that objected to the traditional design. It was a good faith effort to show our concern over the complaints we were hearing. I told Joe that I had some experience at sound attenuating diesel powered generators at the Kohler Company in Wisconsin. So I went to work on the project with confidence that I could put an end to these field complaints.

I took our largest blower at the time and with my engineers, technicians and computer designers began a study to identify where exactly the different audible sounds and frequencies were coming from on the unit. The easiest to identify was the source of the high pitched whine, which was coming from the impeller blades within the main blower housing. Another source of noise was the exhaust muffler, which at that time was intended mainly to prevent sparks without introducing a power robbing back pressure on the two stroke engine. We also found that the combustion air intake was a contributor for there was always a bit of blowback coming from the air cleaner that sounded a lot like a muffled exhaust sound. Finally, there was the sound of the internal explosion itself that emanated through the wall of the air cooled engine to the cooling fins which tended to convert combustion vibration to an audible sound.

Each unique sound in turn, from the loudest to the least audible, was diminished to where it would blend in with the background noise of the engine. Without these visible peaks on the sound spectrum analyzer, the sound of the blower became indistinguishable from other lawn care products; however the overall sound level still was higher than we wanted. To accomplish our final goal, we developed a new exhaust muffler, an air cleaner with a patented sound attenuator and an engine housing that had sound attenuating materials (foam) bonded to the inside of the housing to absorb combustion noises. In addition, the hard plastic housing material was a special composite with sound deadening and vibration absorbing capabilities. As a result, at 65 dB(A), we achieved a 75% reduction in overall sound and we did it at no additional cost to the consumer and with no loss in performance. The design turned out to be an award winning concept that revolutionized the leaf blower industry. In subsequent years, Echo redesigned all their leaf blowers to a new sound reduced Standard.

It happened at that time that emissions became an issue at the government level and our entire line had to be modified and improved. In the process, special attention was given to the concept of sound attenuation. Every new blower was significantly quieter than the one it replaced, most achieving at least a 50% reduction in sound. Several paralleled the original design in that they were 75% quieter. The most significant improvement to all Echo leaf blowers was and is the elimination or attenuation of the impeller whine so prevalent in older designs.

The hope in all this was that those wanting to do something about leaf blower noise would now have an alternative to banning. As I write this article in late 2010, I find that we have made great strides in educating communities to the facts about leaf blowers, but still there are some that find these facts difficult to accept. What the anti-leaf blower activists have not accepted is that they have won. Because of their persistence, the industry has spent millions of dollars to improve the leaf blower and has gone the extra mile to provide educational materials that can be used to teach operators in the proper way to use a blower. Both Echo Inc. and the Outdoor Power Equipment Institute (OPEI) have created manuals that explain what the issues are and what must be done to make using a leaf blower acceptable to others.

It is my hope that one day soon; anti-leaf blower activists will abandon their effort to create an unenforceable leaf blower ban and begin to lobby instead for a worthwhile ordinance that eliminates old, noisy and exhaust polluting products. They should help communities set up training programs in local trade schools for professional operators and make training manuals available to private citizens and homeowners. In addition, their new ordinance should limit the hours of blower use to normal business hours and days of the week.

For detailed information suggesting how all these suggestions can be accomplished, including a recommended workable ordinance, see the following web site: http://www.leafblowernoise.com/.

Larry Will, Consultant

Echo Inc.

(479) 250-4110