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3+3 Ratio Acoustic Guitar Machine Heads (PRN-2411, 2421, Select Finish and Button Style)

3+3 Ratio Acoustic Guitar Machine Heads (PRN-2411, 2421, Select Finish and Button Style)

PRN-2411-C0

702725245994

Regular price $114.99 USD
Regular price Sale price $114.99 USD
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Select Finish
Select Button Style

RATIO® patented gear technology
RATIO® - Calibrated Machine Heads incorporate different string gauges into the tuning equation.

From Low E to High E 39:1, 24:1, 20:1, 14:1, 20:1, 12:1.

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.

RATIO Machine Heads explanation video

 

The PRN-2411 and PRN-2421 are the right-handed sets of RATIO® Calibrated Machine Heads for acoustic guitar that use 3 per side tuners.

It has a two-pin casing that can be used as is, or with our Patented InvisoMatch Mounting Plates [opens in new tab].

4 different sets of InvisoMatch mounting plates in brushed aluminum are included to make installation on most guitars fast and accurate by using your existing screw mounting holes.

 

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: 13/32" (10mm)
String post diameter: 0.236" (6mm)
String post length to string hole: 0.910” (23mm)
Weight per single machine head: 0.066lbs (30g)
Weight per set of six: 0.393lbs (179g)
String diameter up to 72 gauge
Includes 6 machine heads, mounting screws and bushings
Includes complimentary 4 sets of aluminum mounting plates

UPGRADE TO PREMIUM PLATED INVISOMATCH View full details
4.9
Rated 4.9 out of 5 stars
Based on 236 reviews
Total 5 star reviews: 225 Total 4 star reviews: 10 Total 3 star reviews: 1 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend these products
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236 reviews
  • RD
    Ryan D.
    Verified Buyer
    Ratio Tune-a-Lele Ukulele Tuners 6:1 with Large Buttons (4 pcs)
    Reviewing
    Ratio Tune-a-Lele Ukulele Tuners 6:1 with Large Buttons (4 pcs)
    Rated 3 out of 5 stars
    1 week ago
    Almost perfect

    Love the lightness and the lack of backlash. They seem really well made and didn't take much work to mount these from my originals.

    The originals are 16:1 single screw with a nut that holds the tuner in without needing the screw for structural support.(I like this because it doesn't put undue pressure on the hardware or the ukulele)

    The design for installing this new hardware gives me pause. All of the stress of the sting is put on the screws and the post has just a touch of flex in it which forces the grommet in the front to gap and attempt a walk out maneuver. I have only replaced one so far, for a repair, and am waiting to see if the tuner holds. The cosmics are small enough to be ok but I don't like the flex the head gets. The longevity is questionable.

    I really want this product with a better mounting system. It's such a nice product. The finish and gearing are great.

  • GT
    GUOMING T.
    Verified Buyer
    Ratio Tune-a-Lele Ukulele Tuners (4 pcs)
    Reviewing
    Ratio Tune-a-Lele Ukulele Tuners (4 pcs)
    I recommend this product
    Rated 5 out of 5 stars
    1 week ago
    Setup

    Good and easy setup

  • RA
    Richard A.
    Verified Buyer
    6 String 3+3 Bass Ratio Y-Style Button (PRB-6330, Select Finish)
    Reviewing
    6 String 3+3 Bass Ratio Y-Style Button (PRB-6330, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    2 weeks ago
    They rule

    They stay in tune better and I had good tuning machines on my bass. They're worth it 100%. Fast tuning too.

  • D(
    Donat (Woody) L.
    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
    3 weeks ago
    Best Tuners

    This is my 3rd guitar that I have replaced tuners and I am very happy with these. Makes tuning easier and faster and fine tuning a breeze.

  • GY
    Georgy Y.
    Verified Buyer
    6-In-Line Retro Fender Style Ratio Machine Heads (PRN-4624-N0, Nickel Finish)
    Reviewing
    6-In-Line Retro Fender Style Ratio Machine Heads (PRN-4624-N0, Nickel Finish)
    I recommend this product
    Rated 5 out of 5 stars
    3 weeks ago
    Those things handle Bass VI strings with ease

    I have Fender Vintera II Bass VI, it came with retro tuning machines and I broke 1 by stripping brass gear.

    Installation is very easy, and no hole reaming was required.

    Included screws were too small so I reused original ones.

    This set handles bass string properly.

    Instead of suggested order I just installed tuning machines in ratio order, as all strings are wound and there are no treble strings.

    The string set is .024 .034 .044 .065 .080 .100, 30” scale

    Finally I don’t have to do a 1/360th turn to tune E.

    While not specifically designed for bass strings I still get major benefits of more accurate tuning across all strings.

    It was a complete shock honestly to discover that guitars still use same gear ratio across different gauges.

    Only downside is that screws holding tuning buttons came loose during first 30 minutes of playing, I added a drop of blue threadlocker and now it’s all good. Obviously it’s not enough to take a star off.

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