-Aquila 'Thundergut' Bass Ukulele Strings

Aquila 'Thundergut' U-Bass Strings

Aftermarket Strings for the Kala U-Bass

Info at the Itailian Aquila website

The Kala U-Bass (read more here) has become an invaluable and beloved instrument to me!  It's essentially a baritone-size ukulele with specialized strings.  The resulting tone is more akin to a traditional acoustic double bass than a ukulele.  It's truly a tonal wonder! my Kala U-bass sporting a set of Aquila Thundergut strings Part of the instruments "magic" is the polyurethane strings that are used by Kala.  A company called Road Toad manufactures these black polyurethane strings and sells them under the name 'Pahoehoe'.  I honestly was very happy with these stock, original equipment strings despite a few peculiarities and maintenance issues.

I found out about the Aquila aftermarket 'Thundergut' U-Bass strings on the internet, specifically a bass-related forum called talkbass.com .  I watched a youtube clip

First off, a little about the original equipment Pahoehoe strings: I really do love the tone and extremely rubbery feel of the original Pahoehoe's. I still do!  They sound huge and the extremely loose tension and bouncy feel force you to play very differently than a traditional bass or bass guitar.  In fact, pretty significant adjustments need to be made to your approach to playing the instrument and even note selection adjustments in some cases.  The sustain is short, but the big tone complements this well. There are some notable drawbacks to the Pahoehoe strings, however - tuning stability is rather poor. I found myself needing to retune every 5 or 6 songs or so after the strings' "breaking-in period" which lasted almost 2 weeks!  The Pahoehoe's were also rather difficult to install, especially the 2 treble strings.  It took me (a competent guitar and bass tech) over half an hour to install and tune up a new set of Pahoehoe strings.  Still, despite these drawbacks, the stock Pahoehoe strings are well worth the effort.

On to the Aquila Thundergut's:  The first thing to notice is the white color.  At first, I was not enthusiastic about the aesthetic change, but I've come around to digging it!  The sound is very similar to the Pahoehoe strings, however the Thundergut has far more treble detail and more acoustic volume.  The volume from the instruments pickup is also a touch louder.  The real difference is the feel & stability!  The tension is much higher with the Aquila's.  You lose a bit of the rubber-band like quality, although the strings still feel very different than any steel or traditional gut string you may have played.  This higher tension facilitates higher speed playing and glissandos as well as helping to stay in tune when sliding to notes!  Players who had a hard time transitioning to the U-Bass would definitely find the Aquila's easier to get used to.  

For me, the added treble response is of little benefit as I tend to go for a deeper, less bright tone with the U-Bass. However, players looking for a more 'modern', full-range tone will love the Thundergut's!

Tuning stability is probably the greatest benefit of the Aquila string.  My set of Thundergut's took only minutes to install and reached tuning stability in only 2 days!  Tuning stability has remained at least 50% better than the stock strings.

 The Aquila's come as a raw string with no ball end or grommet like the Pahoehoes have.  In the 2 pictures below, you can see how I 'salvaged' the red retaining grommets from the stock black Pahoehoe strings and used them on the Thundergut after tying a knot at the bridge end.  The good news is that the Aquila is far easier to install as they stretch less to get to pitch and 'grab' the tuning posts better!  A little less elegant than the Pahoehoe's crimped and grommeted end, but still entirely serviceable!

a set of Pahoehoe strings - note the crimped end and red grommet/washers

Thundergut ready for installation with tied end and 'borrowed' red grommet

Sound

Overall, both strings sound remarkably similar.  The Aquila definitely exhibits more treble range (almost too much in my opinion), but it is easy to 'tone down' with eq.

First, two clips demonstrating the basic 'idea' of a U-Bass with Aquila Thundergut strings installed. The first clip is with no eq, the second clip with about -12db of cut at around 2khz (more like I like it!).  Neither clip has had compression or post-processing.

Secondly, a comparison of the Thundergut's and Pahoehoe's.  Each clip was recorded straight to ProTools with no equalisation, compression or gain compensation.  This is what you get plugged straight in.

Road Toad Pahoehoe:

Aquila Thundergut: