Trial and error in millimeters

The natu-reverb was developed after about 10 years of planning and over 50 prototypes, but even after the basic configuration was finalized, numerous modifications were made to deliver even better reverb.

We objectively analyze our products from all angles and continually make improvements.

On this page, we will explain the attention to detail that goes into our main product, natu-reverb, down to the millimeter level .

▼Spring combination

To create reverb, it's not just a matter of installing a spring.
Even if you arrange springs without any ingenuity, each spring will cancel out the vibrations, and a good reverb will never be produced.

The spring used in natu-reverb is a special spring that was jointly developed with a long-established factory that has been in business for 66 years, and was created after numerous tests.

For example, in the case of the AC-1n for acoustic guitars, all six springs installed have different specifications. We have carefully adjusted and tested everything from the material, wire thickness, spring length, number of turns, and tip treatment to arrive at the optimal combination.

The CG-1n for classical guitars and the UK-1n for ukulele have four springs, but this is to suit the vibration characteristics that are significantly different from those of acoustic guitars.

▼Role of aluminum frame

natu-reverb's reverb is not just made up of springs. In fact, the aluminum frame also has a great deal to do with the quality and quantity of reverb.

Initial prototypes used hard woods such as rosewood, but they later experimented with other woods and metals, including brass and stainless steel, and found that aluminum produced the most natural reverb. I understand.

Of course, it's not just the materials.
The thickness, width, and length of the aluminum were repeatedly adjusted in 1mm increments to arrive at the current specifications.

For example, in the update implemented in May 2023, the width of the side aluminum frame was reduced by 2mm. This suppresses the hardness of the reverb, making it possible to obtain a milder and purer reverb than before.

▼Role of legs

The legs are also a very important part of reverb transmission .
We also tested every possible material, diameter, and length for this part.

For example, there was an opinion that it would be better to make the legs thinner, but when we actually tried it, the reverb became weaker. This is because the thinner legs have lost their rigidity and become unstable, and vibrations have been absorbed by the legs.

We continue product development by repeating this kind of detailed trial and error over and over again.

▼Meaning of caseless design

At the beginning of development, there were design concerns about the exposed spring.

For this reason, we tested prototypes housed in cases made of aluminum, wood, plastic, etc., but the quality of the reverb deteriorated significantly. This is because the vibrations that should be transmitted directly to the springs and instruments are absorbed by the case and dispersed.

Due to the nature of the product being housed inside the body, sound quality is an overwhelmingly higher priority than design, so we have adopted a caseless design with open springs.

▼Please try it out

In this way, natu-reverb was modified many times from all angles before it was introduced to the world.

In other words, natu-reverb is the ``crystal of countless setbacks and a spirit of challenge.''

Please pick it up and experience its reverb.

If you have any questions about the product, please feel free to contact us.