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4 String 4-In-Line Bass Ratio Open Back Classic Clover Leaf Button (PRB-4401)

4 String 4-In-Line Bass Ratio Open Back Classic Clover Leaf Button (PRB-4401)

PRB-4401-C0

702725245239

Regular price $195.44 USD
Regular price Sale price $195.44 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 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-4401 is a right-handed set of RATIO® Calibrated Machine Heads for BASS that use a 4-in-line 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 4-in-line  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 158 reviews
Total 5 star reviews: 152 Total 4 star reviews: 6 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend these products
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158 reviews
  • NF
    Nardo F.
    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
    16 hours ago
    Amazing keys

    If you have pot metal tuners, toss them out , these are very high quality, and the function off the chart .

  • PP
    Pasi P.
    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
    22 hours ago
    Well worth the price.

    Replaced my puke green machine heads on my ES 135 with these and I am very happy. Fits like a glove...

  • JR
    Joseph R.
    Verified Buyer
    3+3 Ratio Acoustic Guitar Machine Heads (PRN-2411, 2421, Select Finish and Button Style)
    Reviewing
    3+3 Ratio Acoustic Guitar Machine Heads (PRN-2411, 2421, Select Finish and Button Style)
    I recommend this product
    Rated 4 out of 5 stars
    Yesterday
    Time for a change.

    I liked the ease to install. The quality appears top shelf. Forty years of heavy use destroyed my original machine heads. This was a necessary change to maintain tune. I am pleased with the decision to purchase from graphtech. I'll report back if they fail to function as intended.

  • MT
    Matthew T.
    Verified Buyer
    7 Strings: 3+4 Ratio Electric Locking Machine Heads (PRL-8621, Select Finish and Button Style)
    Reviewing
    7 Strings: 3+4 Ratio Electric Locking Machine Heads (PRL-8621, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    2 days ago
    They are very nice tuners

    Hello! I put these tuners on my Jackson JS22-7 string. The post height is subtly lower, but they fit very thick gauge strings and lock. The post height is probably more optimal. I wish I knew that it was possible, and desirable, to buy the black colored adapters and that I would have to use adapter plates. I'm not bagging on the adapter plates - they are an advance, and made installation super easy. I just wish I had the black ones. It stays in tune well. Good stuff!

  • MW
    Mark W.
    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
    3 days ago
    Fantastic machine heads

    Fantastic tuners which were a straight swap on my FMT Telecaster. Took all of ten minutes to install and restring. The stock tuners were OK but these are so much better. The ratios of the gearing makes a huge difference. I'm planning to get some for my other guitars. Utterly fabulous!

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