Launched in June 2005, the Installation Series speaker range is Yamaha’s first loudspeaker range dedicated to the needs of commercial audio installations. It follows in the footsteps of many loudspeaker innovations Yamaha have made in other areas such as hi-fi, studio monitors and musician’s speakers.
Yamaha’s own Tim Harrison wanted to learn the background about the design and development of the series, so he interviewed the Installation Series Development team at Yamaha Corporation of Japan headquarters, in Hamamatsu-city, Shizuoka, Japan.
1. High-end installation loudspeakers are a new area for Yamaha commercial audio, and the market is already very established. What was the driving force behind taking the bold step of producing this new series?
Yamaha aims to be a system solution provider. In other words, we want to cater for everything from the moment you receive a signal to the moment that signal is output to the listener. Although we have established our position as a manufacturer of mixers, our other product lines are not yet at the level we want. In terms of speakers in particular, we had products aimed at the music production market, but nothing suitable for the commercial audio market. While there are many speakers on the market already, some of them have problems. We decided to enter the market because we believe that Yamaha is able to bring creative solutions and values not available from other manufacturers to the commercial audio sphere.
2. Can you outline the key people behind the development of the series and the skills they brought to it?
Product Planning: Shinjiro Takeda - Product planning, design philosophy planning
Product Development: Akira Nakamura / Tatsuo Saeki / Yuji Yamashita - Evaluation and refining of prototypes, sound quality decisions
Product Development Collaboration: Michael Adams (ACE) - Enclosure design, driver selection, network design
Application and marketing materials: Ken Iwayama, Shinya Sonoda, Motome Tanaka
3. With so many speakers available today, what makes these loudspeakers unique?
When we talked to customers, we identified two key problems of other speakers on the market, which we have addressed:
“Family Sound”
We have tried to keep the sound uniform across our range of models, eliminating any unnatural qualities when multiple different models are used together.
“Uniform Phase response”
By minimizing phase differences between models, we have also minimized the change in characteristics typically found in a speaker array, something other manufacturers have been unable to do.
Installation speakers require adjustments such as equalization to make them suitable to the configuration of their cluster, the acoustic conditions of their environment, and the way they are used.
We have publicly announced our “White Canvas” concept, which expressed our desire to provide an easily adjustable speaker for system designers and installers. To compare this to painting, a red paint must be “red” on the canvas. You need a “white canvas” if you are to really bring out any coloration. In terms of a speaker system, we believe that a “white canvas” system is one that not only has flat amplitude characteristics but also responds linearly to equalization.
We have come up with a way of standardizing phase characteristics to solve the problems of large changes in amplitude characteristics and non-linear responses to equalization that occur when multiple speakers are used in an array, which has also resulted in an easily adjustable system with a “family sound”.
We believe that it is impossible for system designers and installers to achieve these standardized phase characteristics and “family sound” using EQ or all-pass filters on speaker systems available from other manufacturers; the EQ processing used to obtain a “family sound” alters the phase characteristics of the speakers. In other words, it is very difficult to achieve a “family sound” while maintaining standardized phase characteristics.
As speaker designers, achieving both these goals was a difficult and satisfying challenge, but we are confident that in the Installation Series we have been successful, and would like to see our “white canvas” used to good effect in the real world.
See Technical Philosophy for more information.
4. What are the main areas you expect the Installation Series to be used?
The primary applications we designed the series for are:
5. Yamaha are known for budget portable speakers such as the Club Series. What makes these different?
The Club Series are sold in instrument shops, and are really aimed more at the amateur user.
The Installation Series, on the other hand, has to meet more professional expectations of the installation market where selection is done by a contractor or a consultant.
6. The current trend seems increasingly to be for the use of line arrays. What made you choose to produce large model conventional designs such as the IF3115 three way instead?
In sound reinforcement, line array is generally the rule. However, we are assuming that for installations users make the decision of whether to go with line array or conventional configurations based on factors such as the use, purpose, and installation environment in which they plan to use the speakers. Coverage area is a vital factor in designing for installations. As installation space for speakers is usually limited, in many cases line arrays cannot provide uniform sound pressure and quality at the sound receiving point, so conventional CD-horn equipped point source speakers are better suited to the job. The IF3115 is a point source speaker that provides directional control down to the mid-range.
7. How did the collaboration with Michael Adams of ACE (Audio Composite Engineering) come about?
We selected five or six manufacturers as potential partners for collaboration, and after visiting them and conducting some interviews we settled on ACE. We had a lot of respect for Michael's experience, and he really seemed to understand our design concept. ACE have a lot of experience with a number of well known brands already, so they had a proven track record too.
8. Why was the decision taken to produce the IS series as passive rather than self-powered?
Since Yamaha is a newcomer to the installation speaker market, we want to gain recognition for our passive products before moving on to self-powered speakers.
9. How did you go about deciding the different size models in the range?
The twelve- and fifteen-inch models are essential as the main speakers in our lineup.
After evaluating both small- and medium-size speakers, we ended up basing our line-up on the results of a concept evaluation carried out by selected customers.
10. How did you go about deciding the different horn dispersions and dimensions?
We did some market research to find out what was needed, which showed that people were using 60° x 40° and 90° x 50° for their main speakers. It's nice to have the 90° x90° and the AS asymmetrical horn models. Many people thought that 90° x 60° horns were easiest to use with eight- and five-inch models, and we decided to reflect this in our products.
11. How did you go about deciding the cabinet volume, size and materials?
For our cabinet volumes we looked at existing comparable products and made computer simulations to help us come to a decision. We tried out a range of different materials for our cabinets and chose one that gave the best sound.
12. How were the different drivers chosen? Hours of listening tests or…?
First we built the IF2115/64 reference model to settle on a direction for the sound quality of the series as a whole. We then tested a number of different drivers using that reference model before selecting one that gave the best mid-range reproduction. To make the “family sound” concept a reality, we carried out repeated listening tests for each of the other models and chose drivers that gave the closest sound to that of the IF2115/64.
13. How did you go about “voicing” the series?
We paid particular attention to mid-range reproduction (the range of the human voice), before moving on to adjust the enclosures and drivers to maximize bass reproduction without exceeding their limits. Lastly we used listening tests to fine-tune the degree of sustain and roll-off (the horn EQ) in the high end.
14. How did you go about designing and optimizing the crossover network?
We designed a cut-off frequency and slope to provide a smoothly connected frequency response of LF and HF drivers, and also for the phase response transition between drivers to be smooth; i.e. without a sudden change. We also configured all IS series models to have similar phase characteristics.
And, we designed to the sound and the phase response of the passive mode to be as close as possible to the bi-amp mode which we used as a reference.
15. How did you decide the power levels of the cabinets?
This was largely determined by the target SPL of the likely applications of the cabinet and the appropriate drivers. For the twelve- and fifteen-inch models, we decided to bring out both high and medium power models to cater for a wider variety of applications.
16. The importance of phase response is stressed heavily. What led you to place such a high emphasis on phase?
When you are dealing with stand-alone speakers, it is important that they have a constant group delay. Speakers don't reproduce the original sound if there are variations in group delay. Constant group delay results in linear phases characteristics, which is why we were so careful with phase linearity.
When you want to use speakers in combination, level cancellation due to phase differences becomes a problem, so we thought that a speaker system with minimal difference in phase between models was important.
Many of the major manufacturers haven’t been able to achieve this, despite their marketing claims, and we have heard from clients that this has actually caused problems in some installation sites. These problems can’t be “fixed” by an installer with EQ or delay, as they have to be right “in the box”.
17. You have a legendary reputation, as the designer behind the world famous NS-10M Studio monitor.
How does designing a high power controlled directivity loudspeaker for the installation market differ from designing studio monitors? Was there a lot of experience that could apply to the IS range, or was there a lot of new things to learn?
I develop all types of speaker systems, be they studio monitors, Hi-Fi audio, or high powered speakers for installations, in the same way.
Firstly, I place great emphasis on making speakers with excellent fundamental physical characteristics. In other words, I aim for a speaker with an even acoustic pressure frequency response, and good distortion characteristics.
I tailor the directional characteristics to fit the intended purposed of the speaker.
I give such high priority to good physical characteristics because they give a speaker the ability to reproduce a signal from almost any source. Speakers with bad physical characteristics (those with peaks in their acoustic pressure frequency response) will always result in some distortion of the original sound, which prevents you from getting faithful sound reproduction.
Once I get the physical characteristics right, I then make adjustments to get the best sound possible while maintaining those characteristics. I concentrate on achieving sufficient mid-range to achieve clarity, and then tune the high and low end so that they give a good balance. I also try to give them good sound separation, a sense of depth and three-dimensionality and focus. The ideal sound is the same for any speaker.
18. What design tools are there to aid customers?
We invested a lot of effort into developing tools to aid installers to use our speakers effortlessly. Aside from the usual documentation you might expect from Yamaha, we also produced…
19. Y-S3 software is an innovative and unique design tool. What motivated the decision to produce it?
EASE is the most commonly used design tool, but it is difficult to use and requires the user to spend a great deal of time entering information on the building. We developed Y-S3 with the idea of providing simpler, easy-to-use software to users of the Installation Series.
20. What about support? Installation customers expect a lot of design and electro-acoustic support. How are you going to tackle that?
Yamaha is one of the few manufacturers that supply products like power amplifiers and signal processors in addition to its line up of speakers. We developed the Y-S3 software to take advantage of that, which we supply to our users free of charge.
As a total system design package, this software aids users in the selection and configuration of speakers, amplifiers, and processors, and we also provide an “Application Guide” including a guide to choosing an amplifier and limiter settings. And of course Yamaha has many staff that customers can call.
21. The installation series supports passive and active drive modes.
For most applications how do you see the pros and cons of the two modes? How do you go about choosing between them?
The active mode uses electrical control, so it is able to provide better characteristics than the passive mode. Since limiter settings have been optimized for each driver, active mode is able to drive the speakers with greater safety. What's more, in active mode there is minimal electrical loss due to resistance in the internal network, so it is very energy efficient and giving high sound pressure levels.
On the other hand, passive mode is very cost effective. Contractors are often asked to provide “Value Engineering” in their work. In many cases, they design for active drivers, but then change to passive due to budget restrictions. We have provided the ability to switch between these modes easily to deal with just such cases.
22. The subwoofers feature both parallel and discrete drive modes. Why is this offered? How do you decide which is best for which applications?
Parallel mode places a large load on the amplifier. Discrete mode is therefore useful as it reduces amplifier loading while providing a large output. On the other hand, there is a lot of demand from the market to reduce the number of amplifiers needed in an installation by driving speakers in parallel, which is why we offer the capability to switch between parallel and discrete modes.
23. Can you briefly describe the design process from concept to production?
After much work gathering information from customers and on existing products, the design brief was developed and the required specifications were drawn up. Then the model line up was sketched out and finally a development plan made. We then collaborated with ACE on this plan, and they produced prototypes of the fifteen inch model as a reference. A period of back and forth development between Yamaha Japan and ACE followed in which refinements were made to drivers, horns and cabinet tuning, and then we finalized the design. We then developed the remainder of the range based on that, and then developed a manufacturing plan so that our factory in Thomaston Georgia, USA could commence production.
24. What quality assurance tests are carried out at the end of production?
We carry out the following tests on all speakers before shipping:
1. Sine wave (20Hz-20kHz) sweep testing
2. Sine wave (20Hz) rub and buzz testing
3. Measurement of sound pressure frequency response characteristics
4. Phase checking for all input connectors
5 Visual inspection
25. Yamaha has extensive experience in drop & vibration tests as used on the mixing consoles. Are these applied to the IS Series?
Yamaha has been making and developing commercial audio products for many years, and has put this experience to good use in the production of the Installation Series. Yamaha mixers owe a lot of their reputation for being strong and resilient to our drop and vibration testing. We carry out a thorough testing regimen built on experience and results, not just on mixers but also on a wide range of products. And of course, we also have a lot of experience in testing speakers.
Written by: Tim Harrison from Yamaha CA Support Centre Europe.
Tim is the “output side” product specialist, specializing in loudspeakers, amplification, signal processing, control and digital audio networking. He joined Yamaha in 2005 after working in installation sales, project management and distribution.
