All extensions are custom built on a per customer basis and cannot be sold separately. It is highly recommended to have all extensions permanently attached for stability. Any one of the extensions will increase the depth of the the existing low notes of your clarinet, and so most players prefer leaving the extension attached.
Low E-flat Extension - $599
The Low E-flat Extension increases the range of your standard B-flat or A clarinet, allowing it to play down to a low E-flat (instead of low E). This is similar to Full-Boehm instruments of the past. The most obvious benefit is that you’ll be able to play a half-step lower on your clarinet. A nice side benefit, however, is that the low E will sound fuller and more robust.
The extension consists of one extra key, which is located to the right of the E/B right-hand pinky key (as on bass clarinets and Full-Boehm instruments). It is also necessary to add a short length of wood between the lower joint and bell to accommodate the extra tone hole.
It is preferable to have the clarinet extension permanently attached, as the low E-flat tone hole is located on top of the existing tenon. However, the extension could be made removable if necessary for an additional fee.
Low C Bass Clarinet Extension - $3150
Instead of buying a costly low C bass clarinet, you can now purchase a much cheaper low E-flat bass and add an extension. Depending on the price paid for the bass clarinet, the total cost will usually be less than $5500. Compare that to an $8500 minimum price tag for a decent low C bass clarinet, and you’ll see why many players are going this route.
The Low C Bass Clarinet Extension takes your standard bass clarinet with a range to low E-flat and allows it to play to low C. When finished, it will be very similar to a standard low C bass clarinet. The extension consists of a piece of aged Grenadilla wood, which is inserted between the bell and the lower joint. Three thumb keys operated by the right-hand thumb control the three lowest notes.
Many low C basses have a right and left-hand D key. This is not completely necessary, as once you are accustomed to the thumb keys, it becomes easy to play any combination of notes. However, these keys can be added for an additional fee.
It is preferable to have the Bass Clarinet Extension permanently attached for stability. However, it could be made semi-permanent or detachable for an additional fee.