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6-In-Line Ratio Electric Guitar Machine Heads (PRN-2721, 2731, Select Finish and Button Style)

6-In-Line Ratio Electric Guitar Machine Heads (PRN-2721, 2731, Select Finish and Button Style)

PRN-2721-C0

702725246076

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, 35:1, 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-2721 and PRN-2731 are right-handed sets of RATIO® Calibrated Machine Heads for electric guitars that use 6-in-line 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.

 

6-in-line 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: 13/32" (10mm)
String post diameter: 0.236" (6mm)
String post length to string hole: 0.890” (22.6mm)
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
5.0
Rated 5.0 out of 5 stars
Based on 247 reviews
Total 5 star reviews: 236 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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247 reviews
  • JA
    JAMES A.
    Verified Buyer
    3+3 Ratio Lefty Electric Locking Machine Heads Contemporary Button (PRL-8311-L, Select Finish)
    Reviewing
    3+3 Ratio Lefty Electric Locking Machine Heads Contemporary Button (PRL-8311-L, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    1 month ago
    The Best Product Ever!

    I love the quality and craftsmanship of these tunners.

  • SS
    Stephen S.
    Verified Buyer
    3+3 Ratio Acoustic Locking Guitar Machine Heads (PRL-8411, PRL-8441, Select Finish and Button Style)
    Reviewing
    3+3 Ratio Acoustic Locking Guitar Machine Heads (PRL-8411, PRL-8441, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    2 months ago
    Love these tuners!

    I just installed GraphTech locking ratio tuners on my fifth guitar and they are, as usual, fantastic. The truth is, once you've tried these tuners, there is just no going back.

  • PT
    Peter 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
    2 months ago
    Great friction peg replacements for old ukes!

    They’re great - very light! I’ve used them before to replace friction peg tuners on old ukes with positive outcomes. Recommended!

  • TM
    Ty M.
    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
    2 months ago
    Tuners

    These work well, I did not need the additional gold plates

  • GY
    Georgy Y.
    Verified Buyer
    7 Strings: 7-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721-x7, PRL-9731-x7, Select Finish and Button)
    Reviewing
    7 Strings: 7-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721-x7, PRL-9731-x7, Select Finish and Button)
    I recommend this product
    Rated 5 out of 5 stars
    2 months ago
    Perfect pitch black (see what I did here?)

    Best tuners on the market, no contest, competition is not even close.

    Quality on par with the best of the best, functionality is better.

    Used 7 string set for B standard tuned (13-64 strings) Jim Root Jazzmaster and skipped number 4 tuner (d string)

    So I installed 7-6-5-3-2-1. I could use #4 tuner for 13 gauge string, but because it’s staggered it’ll be taller than #2 tuner post.

    I find most benefit of ratio tuners are on wound strings so you don’t have to do 1/360th turns on thick gauge anymore.

    Installation took like 3 minutes on top of restring, black fender plates = no drilling and great angle behind nut due to ever so slightly reduced post height.

    2 main downsides of ratio tuners:

    1. Price bites.

    2. You want them on ALL YOUR GUITARS after trying once. Both downsides combined get pricey real fast.

    Only guitar I wouldn’t install ratio tuners is one with evertune bridge. Regular lockers are enough there.

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