OUR TECHNOLOGY TO IMPROVE AND CONTROL ACOUSTIC SOUND

     The technology that we use to improve musical sound is simple and is easily understood.  First, consider how a stringed acoustic instrument creates sound.  Our opinion about this is summarized in the next paragraph. 

    The musical sounds that we hear from our musical instruments, as well as from our radios, occurs when they create air pressure waves which impact our ear drums.  Before the sound from our radios came from its speaker those air pressure waves existed as two different representations of “sound” which we don’t hear - waves of voltage and current inside the circuitry of the radio, and before that as electromagnetic waves in space.  These inaudible waves are (or can be today) accurate representations of the original music when they are changed into audible sound by the speaker.  Stringed musical instruments do something similar.  They create audible sound as a last step in a process of several steps which begins with mechanical waves on the strings which we don’t hear.  These waves on the strings are transferred by physical contact both through and over the bridge to the top and body of the instrument.  They move over all surfaces of the instrument as mechanical surface waves which are much like water waves on the surface of a lake.  (Waves of a different type also travel through the instrument’s materials to some extent.)   On the instrument’s surfaces the surface waves are reflected from the edges of their surfaces onto themselves and onto similar waves reflected from other edges.  Their meeting coming from different directions causes them grow (amplifies them) just as similar reflected waves get bigger when they meet on the surface of a lake.  When the distances between edges on the instrument’s surfaces are a good match to the frequencies (and wavelengths) of the surface waves, large “up” and “down” (or “in” and “out”) pumping motions (standing waves) result, most noticeably on the instrument’s top or soundboard.  This pumping motion moves enough air to create large air pressure waves from the instrument which we hear as musical sound.

    Thinking about the radio again, when you want to change its volume you simply turn the volume dial.  And when you want to change the timbre or “character” of the sound you move the bass and/or treble dials.  In doing so you are changing the electronics in the radio, not the air pressure waves. Because the manufacturer knows that it is easier and cheaper to change the electronic form of the “sound” than to change the air pressure waves by modifying the speaker. 

    Our technology uses this same approach.  We don’t change the musical instrument to create better sound from it but change the thing that creates the sound in the first place - the instrument’s sound surface waves.  Using the instrument’s surface waves we can easily and cheaply increase volume simply by collecting the surface waves (by contact) and amplify them by forcing them over shapes that reflect them onto themselves and similar surface waves which causes them to amplify.  This common type of mechanical amplification is known as amplification by “constructive interference”.   (You can “Google” it or read more about it on the “Glossary” page here.)  

    And just as in the example of the radio we can change the timbre or sound “character”.   We do this by routing some of the surface waves over different materials.  This causes the waves to pick up the timbre characteristic of the material.  We use small, thin pieces of steel to create a bright, crisp sound, brass to create a more resonant sound and maple wood to create a clear wooden sound.   These materials have shapes of squares or rectangles, some with a small hole to scatter and so amplify high frequencies.  These shapes are also surface wave amplifiers because they reflect the waves. 

    Another benefit of changing sound surface waves to improve musical sound is that sound quality can be improved easily and cheaply.  It is widely recognized that a strong presence of harmonics in musical notes often improves the quality of musical notes.  (Harmonics are waves with a frequency that is a multiple of the main or fundamental frequency).   Amplified harmonics can improve the sound quality of all notes played, including the lowest notes on the instrument.   So our approach to improve sound quality is to insure that our devices amplify the highest possible frequencies - not only in their surface wave form but also in their air pressure wave form - the music that you hear.

    This last step, converting greatly amplified, harmonic-rich and timbre-enhanced surface waves into high quality audible sound, has been our biggest challenge over the years.  We found that the best way to accomplish this final step is by routing the waves into pointed shapes of thin materials which causes the waves to grow as they approach the points.  This wave growth, which is due to decreasing space for the wave’s energy, is not unlike the way a tsunami wave grows as it approaches a beach and runs out of water for its energy.  (See, “tsunami effect” in the Glossary.)   The thin, tiny paper points are able to vibrate very fast and so move air at harmonic frequencies.  How do we know?  Because the instrument sounds richer and much better.

    At least it sounds much better on our test instruments to us.  What sounds great to one player, on one instrument, in one venue or playing situation, may not be ideal in other situations.  That is where our tone amplifiers, the small rectangles or squares of wood or metal, come into play.  For example the same tone wing that sounds so good in our Gibson Mastertone CGDA tenor banjo with no tone amplifiers (wood or metal squares or rectangles) doesn’t sound bright enough for our Gold Tone CC Irish tenor banjo tuned GDAE.  But simply adding a steel harmonic amplifier under the input tape gives the inexpensive Irish banjo a bright, crisp sound that seems perfect playing in a pub session.

     So that’s how our devices work.  - How our simple paper shapes temporarily stuck to the top surface next to the sound opening and  extending into the sound chamber, or attached to the inside surface of a banjo’s wood rim, sometimes with tone amplifiers of wood or metal amplifiers for tone control, can create beautiful, loud sound from many acoustic instruments in many different playing situations.  

    ”Why haven’t I heard of this new technology before?”  The answer to this expected question is probably because it is new.   We seem to be the first to exploit, if not discover, the amazing potential of sound surface waves to improve the sound of musical instruments.  (We also seem to be the only ones now working in this field.)  Having no competition over about eight years we were able to discover various methods to control, amplify, timbre-modify and finally convert sound surface waves into audible sound.  Then we invented inexpensive devices which used these discoveries to improve the sound of musical instruments.  (Most products on this website are either patented or have patents pending.)   Because our products are protected we are happy to share information about how we believe they work, and do so primarily on the three “theory” pages and blog pages here.  In doing so we hope to encourage others, and especially musical instrument manufacturers, to experiment with musical surface waves.

    Guarantee:  Satisfaction is unconditionally guaranteed on all products for 30 days or the purchase price will be refunded on return of the used but unmodified product by the purchaser.

   Services Offered:   In addition to selling our tone amps from this web site we offer informal educational seminars and consulting services to companies who wish to evaluate the potential of sound surface waves for their future products.   We do this because we believe that an understanding of sound surface waves by manufacturers will lead to improved instrument designs and better sounding acoustic musical instruments at lower prices.  

    More Details, Pricing and Ordering:  You can read product details on the “Products/Pricing” page, see more photos on the “Photos” page, and order them using a major credit card on the “Ordering Page”, (or order by mail with U.S. check or money order in U.S funds).  Parts orders are by mail only with check or money order.  Credit card payments are accepted through Pay Pal and should be made payable to our Pay Pal account which is geigeracoustic@mac.com.  

   

    Below is a summary of highlights of selected pages on this site:

1.  The three “Theory” pages contain “common sense”, easy-to-understand explanations, pictures and

drawings describing how our products work, including products obsoleted by current products for educational purposes.   Products are arranged in chronological order of development to illustrate the iterative nature of design and experimentation, also for educational purposes.

2.  The “Blog” page.  In addition to providing more technical explanations of how our products work, the Blog page describes recent ideas and devices that improve sound, music and musical performance.   Included in the archive are things that you can make such as tuned banjo bridges, variable volume banjo mutes, and “make-it-yourself” amplifying devices for guitars and banjos.  Be sure to notice the “Go To Archive” link at the bottom of the first page to see older entries not listed on the main page.  Be aware that some retained older entries are far less efficient than current products. 

 

3.  The “Glossary” page defines terms used on this website and common terms related to musical sound and surface waves.  Examples and explanations of theory are also included in some cases.

4.  The “Links” page includes a link for a free download (PDF) of our new 31-page book, “Build Any Chord, Anywhere”, a unique graphical approach to building chords anywhere on the fingerboard for all fretted instruments tuned in fifths. (Tenor banjos, tenor guitars, mandolins, etc.)  It also teaches basic chord theory applicable to all instruments.  Guitarists, 5-string banjoists and bass guitarists can see the color harmony patterns for their instruments in the Appendix on page 29.

  Thank you for visiting.  I hope that you enjoy the site and will try our products.   I offer them for sale only after being very pleased with them after playing and performing with my CGDA tenor banjo (modified Gibson Mastertone Tenor), GDAE Irish banjo (modified Goldtone CC Irish Tenor), GDAE mandolin (Kentucky Style A), Irish fiddle (formerly a rental) and “tenor guitar” (Baby Taylor with four strings tuned GDAE).

                    

                                                                                          Frank Geiger