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5 String 3+2 Bass Ratio Y-Style Button (PRB-5320, Select Finish)

5 String 3+2 Bass Ratio Y-Style Button (PRB-5320, Select Finish)



Regular price $149.44 USD
Regular price Sale price $149.44 USD
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RATIO® patented gear technology
RATIO® - Calibrated Machine Heads incorporate different string gauges into the tuning equation.

From Low B to G - 48:1, 36:1, 30:1, 20:1, 18:1.

We balanced the gear ratios to each string simplifying the tuning process.

With RATIO®, a half-turn is a semi-tone!

Every string reacts the same to any tuning adjustment. Predictable, precise tuning, on every string.

Bass Ratio animation video

The PRB-5320 is a right-handed set of RATIO® Calibrated Machine Heads for BASS that use a 3 x 2 configuration.


In order to achieve the higher gear ratio's, Ratio's are the world's first machine heads using a double envelope gear design with a hardened steel gear. Amazingly smooth and super strong.


3x2 tuners set  Ratio Tuned Machine Heads: The New Standard In Tuning Technology


Gear ratio: unique for each string position - one turn-one tone
Peg holes diameter required: 35/64" (14mm)
String post diameter: 0.547" (13.9mm)
String post length to string hole: 1.030” (26.1mm)
Weight per single machine head: 1.86oz (53g)
Weight per set of six: 9.3oz (265g)
String diameter up to 0.98 gauge (or larger if taper-wound)
Includes 5 machine heads, mounting screws, and bushings


Staggered Ratio Measurements.pdf Ratio Installation Guide.pdf Ratio Installation Guide Video


Our Bass Ratio rated 5 stars on Sweetwater.

Sweetwater Rating 5.0


Rated 5.0 stars
Based on 2 reviews
Total 5 star reviews: 2 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend this product
2 reviews
  • TH
    Terry Houck, J.
    Verified Buyer
    I recommend this product
    Rated 5 stars
    3 months ago
    Top Quality

    Exceptionally well-made and beautifully designed. Unfortunately, the G tuner I received is out of sync, but their customer service team was quick to respond and offer a replacement part. Great buying experience.

  • RS
    Reza S.
    Verified Buyer
    I recommend this product
    Rated 5 stars
    4 months ago
    High quality machines

    Really solid and well made. I'm extremely happy with these.

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