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4 String 2+2 F-style Bass Ratio - Chrome (PRB-4221-C0)

4 String 2+2 F-style Bass Ratio - Chrome (PRB-4221-C0)

PRB-4221-C0

702725244690

Regular price $195.44 USD
Regular price Sale price $195.44 USD
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RATIO® patented gear technology
RATIO® - Calibrated Machine Heads incorporate different string gauges into the tuning equation.

From Low E to G - 48:1, 36:1, 25:1, and 23:1.

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

The PRB-4221 is a right-handed set of RATIO® Calibrated Machine Heads for BASS that use a 2 x 2 configuration.

 

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

 

Headstock Configuration 2 x 2  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: 0.720" (18mm)
String post diameter: 0.547" (13.9mm)
String post length to string hole: 0.807” (20.5mm)
Weight per single machine head: 3.5oz (99.3g)
Weight per set of four: 14oz (397g)
String diameter up to 130 gauge
Includes 4 machine heads, mounting screws and bushings

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5.0
Rated 5.0 out of 5 stars
Based on 133 reviews
Total 5 star reviews: 128 Total 4 star reviews: 5 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend these products
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133 reviews
  • VV
    Villiam V.
    Verified Buyer
    7 STRINGS: 7-in-line Electric Locking Machine Heads (PRL-8721-C7, Select Finish)
    Reviewing
    7 STRINGS: 7-in-line Electric Locking Machine Heads (PRL-8721-C7, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    1 week ago
    7-in-line ratio machine heads

    Purchased to improve the tunability of a baritone guitar, especially the low strings. They solve the problem well, significantly improving the quality of the instrument.

  • JP
    John P.
    Verified Buyer
    6-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721, Select Finish and Button Style)
    Reviewing
    6-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    1 week ago
    Amazing as usual.

    These are my second set of Ratios. Both are on guitars with old school non-fine tuner Floyd Rose bridges. They are high quality, have smooth action, and keeps things locked in tune. Plus they look great.

  • SB
    stephen b.
    Verified Buyer
    3+3 Ratio Electric Guitar Machine Heads (PRN-2311, 2341, please select finish and button style)
    Reviewing
    3+3 Ratio Electric Guitar Machine Heads (PRN-2311, 2341, please select finish and button style)
    I recommend this product
    Rated 5 out of 5 stars
    2 weeks ago
    Solid tuners

    Feel great, solid, stay in tune. Replaced stock tuners on epiphone casino

  • JC
    jesse c.
    Verified Buyer
    4 String 2+2 Bass Ratio Y-Style Button (PRB-4220, Select Finish)
    Reviewing
    4 String 2+2 Bass Ratio Y-Style Button (PRB-4220, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    3 weeks ago
    Solid well thought out tuners

    Great stability and tuning precision. Great upgrade for any bass or guitar

  • GN
    Greg N.
    Verified Buyer
    3+3 Ratio Electric Locking Machine Heads (PRL-8311, 8322, 8331, 8341, 8351)
    Reviewing
    3+3 Ratio Electric Locking Machine Heads (PRL-8311, 8322, 8331, 8341, 8351)
    I recommend this product
    Rated 5 out of 5 stars
    3 weeks ago
    Graphtech is the best

    Not much else to say here. They are the best in what they do. Pretty simple,…

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