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Aquila 91U Thunder Reds Bass Ukulele Strings 4 String 18-21" Scale

Item# AQU_91U
$29.99List Price $38.00
In Stock & Ready to Ship!

Item Description


The Thunder Reds® sets: a unique look and a strong, consistent sound.

Until now, it was necessary to increase a string’s gauge to reach lower frequencies. But increasing the string’s diameter also increases internal dampening. That makes the string less bright, less responsive and more muffled:

the thicker the string, the duller the sound.

Our revolutionary new approach —never introduced before us— changes the specific weight of the material, increasing it progressively to leave the gauge unchanged.

Thunder-reds is a set made with three different types of synthetic elastomer. In the third and fourth strings, the density of the elastomeric material is also increased by adding micronized metal copper powder during the extrusion phase.

This technological solution allows for the same working tension to have smaller diameters, greater volume and sustain than any type of polyurethane and silicone rubber strings available on the market. The Thunder-reds ensure fast and stable intonation. Thanks to the metallic powder there is also a great slipperiness of the fingers on the strings.


91U Aquila Thunder Reds 4 String Set GDAE 18-21" Scale


Aquila 91U Thunder Reds Bass Ukulele Strings 4 String 18-21" Scale
Aquila 168U Thunder Reds Bass Ukulele Strings 4 String 23-26" Scale
Aquila 169U Thunder Reds Bass Ukulele Strings 5 String 23-26" Scale


4 Reviews
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75% Recommend this product (3 of 4 responses)
By J
Very easy to play; pleasant tone
May 3, 2021
Probably the best strings I came across for bass ukes. Baby powder suggested.
  • Tone
  • Easy on fingers
  • Might need some baby powder to lessen stickiness
By Leland w.
Intonation is great the sound is great to
January 10, 2019
Would buy them again price
  • Price very good
By Reg
Great sounding strings for professional Ubassists.
October 31, 2018
I gig with a jazz trio 3 times each week with my Kala solid body Californian 4 string Koa using Aquila thunder reds exclusively. We play festivals, corporate gigs and jazz clubs and I get consistently good comments on the sound of my Ubass and these strings. I change all 4 strings every 2 months and have never broken a string on a gig. A tiny trace of coconut oil on my fingers allows for very musical slides and precise playing. Aquila 91U strings are a great sounding and reliable string for all my professional playing.
  • Great sound for jazz
  • Hard to find at a good price
By Don
Sunset Beach, NC
Aguilar Thunder Reds
February 7, 2018
I play a Kala acoustic/electric U-Bass. It came with factory strings - black, low tension, Pahoehoes. I swapped those out with Pyramid Copper Round Wounds for a punchier sound. Great! Then I discovered Aguilar Thunder Reds! The sound of the Reds lies between the Pahoehoes and the Pyramids - warmer, with solid definition and better feel.
If you own a Bass Ukelele, try the Aguilar Thunder Reds.

Thanks for stocking these super strings.

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