An adjustable neck member is disclosed having a distal end and a mounting end configured to be coupled to a stringed instrument body. An enclosed channel extending within the neck member from a position near the mounting end and along a central axis of the neck member to the distal end is also provided. The channel may include at least one recess extending laterally from the channel at the distal end. Furthermore, a rigid bar disposed within the channel and having an adjustment end, an opposing distal end, a stabilizing pin, and a transverse pivot support that is configured to vertically displacement of the neck member is also included. In one embodiment the neck member may also include a pressure isolating means which is capable of indirectly applying sufficient pressure to the neck member to reduce any resonating spring vibrations.