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7 Strings: 3+4 Ratio Electric Locking Machine Heads (PRL-8621, Select Finish and Button Style)

7 Strings: 3+4 Ratio Electric Locking Machine Heads (PRL-8621, Select Finish and Button Style)

PRL-8621-C7

702725244522

Regular price $187.77 USD
Regular price Sale price $187.77 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 B to High E 48:1, 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 PRL-8621 is a right-handed set of Locking RATIO® Calibrated Machine Heads for electric guitars that use a 3 x 4 tuner configuration.

Fits many Jackson, Schecter, and Ibanez (selected) style guitars and a lot of acoustic guitars if you want to upgrade to a locking set of machine heads.

 

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.

 

3x4 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: 0.910” (23mm)
Weight per single machine head: 0.083lbs (38g)
Weight per set: 0.581lbs (266g)
String diameter up to 72 gauge
Includes 7 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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