Unlocking tonal gold from the Valco String Thru pickup

    Guest blog by Jeff Senn of Jeff Senn Guitars

    How to set up and adjust the Valco String Thru pickup for maximum tone

    The original Valco “String Thru” pickups designed in the first half of the 20th century have certainly forged a legacy due to their unique construction, tone, and dynamics. By placing the magnets (or one magnet on student models) on each side of the strings and unifying the magnetic field with a connected metal cover and pole pieces under the strings the pickup has a sound and “feel” like no other pickup.

    Lap steel players have been savvy to the incredible sustain and “singing” tone of these pickups for many years but when Ry Cooder attached one to his Fender Stratocaster guitar players all over the world took notice, catapulting the pickup into legendary status.

    In the past the only way to get these pickups was to find and dismantle an old Valco/National/Oahu/Supro guitar but now Valco is proud to make the pickup available on the Airline Lap Steel PRO guitar, the Warren Ellis CDR a version of the iconic “Coodercaster”, and also as a part to install on the guitar of your choice.                                                                                                  

    Photo: Vintage Valco/Supro Pickup 

    Set up and adjustment of the String Thru pickup is crucial to getting the most in tone and volume out of this unit. When the pickup is adjusted poorly or the wrong strings are used the overall sound can be thin and anemic with no punch. There is also limited space to work with since the strings do indeed travel through the pickup and under the top plate.

    The first step in getting your String Thru pickup adjusted properly is to select a string gauge that fits your playing style. It’s no secret to slide players that slightly heavier strings tend to work better for both tone and ease of playing Slide guitar. I’d suggest starting with a set of .011” gauge strings, .012” gauge is even better but here’s one of the big secrets of the string through pickup: They do not respond well to an un-wound third or G string. The difference in sound and overall balance on these pickups using a wound G string as opposed to an un-wound version is a proverbial “night and day” experience. Trust me on this one, install a wound G string! It doesn’t have to be thick in gauge, .020” or .022” will do if you want to still keep the fretting aspect of the action comfortable. You can also experiment with flat wound strings as they also sound great with these pickups and can reduce some of the noise from the slide hitting the strings.

    After you get your playing action and string height set where you want it make sure the strings do not hit the underside of the pickup cover. If you like your action high for slide then you may find you end up shimming the pickup higher with a few thin pieces of wood or plastic.

    The Warren Ellis CDR and Airline Lap Steel PRO should be able to be set up without having to take this extra step.


    This third step is another absolutely crucial step: Adjusting the pickup pole pieces. A Valco String Thru pickup with un-adjusted or flat pole pieces can sound weak, thin, and just plain uninspiring. Since the pickup is so sensitive to right hand attack and picking an un-adjusted version of this pickup can make your playing sound harsh and most of us do not need that when first attempting to play slide.

    If you look at the top of the string through pickup you’ll notice six holes. If you peer through these holes you’ll see a flat head screw or pole piece under each string. By inserting a small, flathead screw driver you can raise (counter clockwise) or lower (clockwise) these screws to adjust how they “pickup” or sense the string.

    To generalize, you’ll want to get these pole pieces adjusted as close to the strings as possible but also make sure that the strings do not hit or come in contact with them when you play. The closer the pole piece is to the string, the louder and more full sounding the string will be. This pickup in particular really responds well to having the pole pieces close to the strings. Some strings, due to their diameter and construction (plain or wound) react differently to the poles or screws so, after getting the pole pieces close and to where the strings do not actually hit them while playing, you’ll want to play the guitar or pick each string slowly and listen…do any of them sound louder than the others? If so, try lowering just the individual pole piece for that string a tiny bit.

    Your end goal is to have all strings sounding out loud and clear but also even or equal in volume.