Thanks for visiting.  I think you'll find this site very interesting.
                  Frank Geiger
This "Ideas & Downloads" Page Includes Thoughts, Suggestions and Recommended Downloads Related To Musical Sound Surface Waves, Our Products and Playing The Tenor Banjo and Similarly Tuned Instruments.  Please See The Blog Page For Additional Information on These Subjects.
    ​​​​Free 31-Page Tenor Banjo / Tenor Guitar Chord Building  Book

This book, which I wrote 10 years ago for tenor banjo and tenor guitar players, can be downloaded free here.  It quickly summarizes chord theory and then uses a unique color graphics method to help the player "build" any chord anywhere on the fingerboard.  The method is based on the fact that the fingeboard location relationships of harmony "levels" of any chord (the "root" or "1" note, the third or "3" note, the fifth or "5" note, etc.) on all fifths-tuned instruments are FIXED!  For example, the 3 is always to the immediate upper left of the 1, the 5 is always to the immediate right of the 1, the 3 and the flatted 7 (7b) always alternate along a diagonal from lower left to upper right.  These fixed relationships are easily seen and remembered by assigning colors to these levels, e.g., Roots (1's) are Blue, 3rd's (3's) are yellow, (5's) are red and flatted 7th's (7b) are Green.   So to build any chord first find any fingerboard location of any root note (the note named in the chord) and then you know the locations of all the other levels of the chord.   The levels you need are defined by the "formula" for the particular chord.  (All chords have formulas.)  For example, the formula for a major chord is, (1,3,5).   So to make a major chord finger any blue dot fingerboard location, yellow dot location and red dot location.  You know where they are now.  Because their locational relationships are always (and forever) FIXED!
The name of this PDF file is: BuildAnyChord,AnywherePDF copy.pdf
3-Page Document "Theory and Directions for Use, Geiger Movable Tone Amplifier For Banjos", (Included with Tone Amplifiers When Shipped) 
This 3-page document is an updated version of the article published in the May/June issue of "All Frets" Magazine except for the  brief and favorable product review at the end by the magazine's Editor, Johnny Baier (See BLOG page). The document describes in non-technical terms how the tone amplifier works and should be of interest to those considering purchasing a tone amp but find it hard to believe that any device made essentially of paper, tape and two staples can amplify a banjo.  It won't cost you anything to find out.  Just click the DOWNLOAD button below the picture to read it on your computer screen or to print it.

The document describes important  recent improvements to the tone amp.  These include: replacing the staple "angle stop" on the right (beneath the steel tone piece) with a small square of 1/16-inch thick foam tape, and how  bending of the tone amp along two new bend lines by the player "aims" audible sound outputs of the tone amp toward each other for unsurpassed volume and sound quality, resulting in truly beautiful sound.   This is the same reason that music is more beautiful when heard in a concert hall and when one sings in a shower.
The name of this file is: Theo&DirRev9PDFSep272017PDF
2-Page Document, "Theory and Directions
Geiger Banjo Bass & Enhancer Amp" (Included with the Product When Shipped)

     Downloading this document enables prospective customers to understand in detail how our new Bass and Enhancer Amp works and how it is installed in the banjo before ordering one.  The Bass and Enhancer Amp began as a simple bass note amplifier to supplement our Banjo Tone Amp, which did a better job amplifying and enhancing high and mid-range frequencies than it did with bass notes.  Our first test showed that the bass notes were amplified OK but didn't sound particularly beautiful and lacked "richness", so we added a high frequency amplifier to amplify the harmonics in the low notes to improve their sound quality.  When we did that, and to our surprise, the new "harmonic amp" not only improved the sound quality from the bass amp it improved all frequencies coming from BOTH amps!  So we changed its name to, "Bass and Enhancer Amp".  The sound from our banjo using both amps was better than the sound of either one used by itself so we highly recommend using both.  Remember that your complete satisfaction is always guaranteed, so existing customers espicially should defimitely order one.

The name of this file is:
EnhancerAmpTh&Inst copy 2PDF
     This 2-page "Theory and Instructions" document (PDF File) describes how our new "Butterfly Dream Sustaining Amplifier For Banjos, Guitars and Mandolins" works.   

     Important: If you primarily play fast bluegrass on a banjo this amplifier may ​not be for you  because the sustain of the amplifier may be too great for fast Bluegrass. (The first note may still sounding when the second note is played.)  

     But its sustain is like a "dream come true" for banjo players who always dreamed of owning a banjo with the sustain of a guitar and also has a great banjo sound.  Which is why we named it the "Butterfly Dream".   

     If you download this document, which is a narrative of how it works, be sure to also download the document below which is a detailed drawing of the amplifier and is frequently referred to in this narrative.  Both documents are included with each order so you can always wait and get them with your order.

     This annotated drawing (JPEG File) will give you a very good idea how our new "Butterfly  Dream" Amplifier works, especially when accompanied by the narrative in the "Theory and Instructions" document above.

     Looking at the drawing you will be able to imagine the sound surface waves flowing from a surface of the instrument down the adhesive layer of the Butterfly Amp's sound wave input tape, then onto its spring steel pin, then onto the brass foil on the Butterfly's bottom surface, and then onto the three staples,  (amplifying on the flat of each staple), from the flat of the first staple onto the walnut or maple wood veneer, and from the flat of the second and third staples onto the diverging paper octagonal planes. The planes create audible sound by "squeezing" the air in the two diverging air spaces between the diverging planes, (as shown in the edge view of Figure 2 with the arrows at the upper left of the drawing).  

     Devote time to this drawing and it will teach you a great deal about what we've learned from our experiments involving musical sound surface waves.
Name of File: DwgButterflyRev6JPEG

     If you are an existing Geiger Movable Tone Amp customer you can receive a free installation upgrade kit consisting of: a 5-inch length of waxed, braided cord, three 3-inch long input tape strips, three size #1 paper clips and instructions by sending a self-addressed, stamped envelope to: Geiger Acoustic Devices, 190 Berwick Drive, NE, Sandy Springs, Georgia, 30328-1205, USA. (The addition of more than one paper clip adds both volume and sustain.)

   New customers will receive these materials with their purchase of a Movable Tone Amp in lieu of the free Travel Caddy previously offered.

     This single page PDF document describes how our new "Supercharger" sound surface wave input structure works in considerable detail.  (Or, at least how we believe it works since we have no proof beyond what we hear in experiments.)

​     You are sure to find it interesting.  F.G.