Double Bass C-Extension Scroll hole. To drill or not to drill?

[robobass]

Probably no aspect of luthiery has advanced and evolved in the past 10 to 20 years as much as C-Extensions. I am constantly amazed at the quality and creativity behind some of the latest work. I wonder about one trend, however. That is the routing of the string back over the scroll into the pegbox, rather than through it. The appeal is obvious, but could there be disadvantages? The tension on the scroll and pegbox, and the bending force on the extension itself are radically altered by this innovation. Will this affect the dynamics of that part of the bass? I have played only one bass with this type of extension. I found that the pegbox/extension vibrated wildly when playing the lowest notes. I didn’t play the bass before the extension was installed (it played normally with the E-stop closed, though), and certainly wasn’t able to play the bass with a traditional extension, so this is no scientific evidence. Since direct comparisons are an unlikely option - finding two new basses from the same maker, with very similar extensions, one over and one through, this is a question that will be very difficult to answer with any certainty. Is anyone else thinking about this? Has anyone any relevant experience?
Robobass

 

[arnoldschnitzer]

I think the hole-in-the-scroll is better, because it helps the extension be more stable, and sends the string on a more direct path to the tuner (less tension). I rely on the string to hold the extension in place as I don't generally use screws. However, I did build one extension in which the string passed through the body of the extension and no hole was required. It worked fine, but changing strings was a drag.

 

[Bob Branstetter]

I think the hole-in-the-scroll is better, because it helps the extension be more stable, and sends the string on a more direct path to the tuner (less tension)

+1

 

[Schoolhouse]

Drilling a hole is the only option on many basses. There simply is not enough room to use three wheels to route the string.