Draw the major tuning slide out to make the tuba longer and thus lower the pitch. Push the major tuning slide in to make the pitch higher. Removing the mouthpiece by force could destroy the braces of the tuba. Thus, do not try to dismantle the mouthpiece yourself if it gets jammed while playing. There is a special tool designed to remove the mouthpiece safely. Before 1730, clavichords were created small with four octaves and a length of approximately four feet but nowadays, these are made with a length of up to seven feet. Nowadays, clavichords are manufactured all over the world and have many buyers in the market. A few modern manufacturers are the British Peter Bavington, Swiss Thomas Steiner, American Charles Wolff, and Belgian Joris Potvlieghe. Its strings could be made of steel or nylon while its top plate could be made of cedar or spruce. At the top is a circular hole with a diameter of 3.25 inches to 3.5 inches which strengthens and reinforces the produced sound. Sound production Generally, guitars produce sound through the strings vibration. Like a bassoon it is somewhat folded and has two parallel straight bores attached at the underside. This structure is fitted for a bassoon because it becomes very long when straightened out but it is actually very peculiar for an instrument that is soprano-sized. If you know what a bassoon looks like, then let us picture out the octavin like this. Blowpipes today usually have a non-return valve so that the player does not need to cover the edge of the blowpipe with his or her tongue when inhaling. The bag is a reservoir which holds air and regulates airflow while pumping or breathing take place. This helps the player to uphold constant sound for a moment. The reed is made of cane. This cane is folded and attached to a short tube called staple which is placed in the wooden pipe s top. Access to the high notes comes with enormous difficulty because of the lack of reed control of wind capped instruments. Its range only encompasses the fundamental sounds made by consecutive opening of the horizontal holes.