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
Couldn't load pickup availability
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.
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.
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
Invisomatch Mounting Plates
InvisoMatch Mounting Plates for RATIO Tuned Machine Heads are the easiest approach to installing Ratio Tuned Machine Heads on your guitar.
Simply select the installation plate design that matches the screw/pin hole location of your factory installed machine heads.
You’ll be up and running within minutes, perfectly installed and aligned. Stay classy you axe master.
For stunning accuracy and response... upgrade to Ratio Machine Heads with it's patented Multi-Geared Tuning Technology.
The new standard in tuning.
NO DRILLING, PERFECT ALIGNMENT, FAST INSTALLATION
With InvisoMatch mounting plates you will reduce the time to install RATIO machine heads to well under 15 minutes.
The alignment of the machine heads is perfect, no holes to drill or fill, ideal for vintage instruments.
Four sets of brushed aluminum InvisoMatch mounting plates come free with every set of Ratio Tuners.
Premium finishes including chrome, nickel, black and gold are available for order.
“After reading some reviews and seeing the ads, I decided to try a set of Graph Tech’s ratio tuners on my American standard Strat. The tuners arrived and I was very pleased with the quality and finish. Installing the tuners was a breeze using the included InvisoMatch plates — no need to drill any holes in my beloved Strat and the performance of these tuners is outstanding!"
"Tuning becomes incredibly easy and holds tune even when using the tremolo bar. I would highly recommend these as a great upgrade to any guitar and will be telling my customers what a great addition they would be for very stable and easy tuning.
Thanks, Graph Tech for a great product.!
Jay Langan / Magdon Music / guitar sales/ guitar tech
Click a picture to open a PDF file with the dimensions.
- RDRyan D.Verified BuyerReviewingRatio Tune-a-Lele Ukulele Tuners 6:1 with Large Buttons (4 pcs)Rated 3 out of 5 stars1 week agoAlmost 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.
- GTGUOMING T.Verified BuyerReviewingRatio Tune-a-Lele Ukulele Tuners (4 pcs)I recommend this productRated 5 out of 5 stars1 week agoSetup
Good and easy setup
- RARichard A.Verified BuyerReviewing6 String 3+3 Bass Ratio Y-Style Button (PRB-6330, Select Finish)I recommend this productRated 5 out of 5 stars2 weeks agoThey 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 BuyerReviewing3+3 Ratio Electric Guitar Machine Heads (PRN-2311, 2341, please select finish and button style)I recommend this productRated 5 out of 5 stars3 weeks agoBest 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.
- GYGeorgy Y.Verified BuyerReviewing6-In-Line Retro Fender Style Ratio Machine Heads (PRN-4624-N0, Nickel Finish)I recommend this productRated 5 out of 5 stars3 weeks agoThose 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.