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Thomastik-Infeld Electric Bass Nickel Flat Wound Roundcore 4 String, .043 - .100, JF344

Thomastik-Infeld Electric Bass Nickel Flat Wound Roundcore 4 String, .043 - .100, JF344
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61 Reviews
90% (55)
7% (4)
2% (1)
2% (1)
0% (0)
11% Recommend this product (7 of 61 responses)
By Shawn A.
Westerly Rhode Island
Great strings!
February 9, 2022
Love these strings, first time trying them out on a recommendation. Playability is incredible super easy on the fingers. Thank you just strings
By Beau
Tampa, Florida
Thomastik-Infeld JF344
May 14, 2021
I've been using these strings for 16 years on my Fender Jazz and Precision basses. The feel, sound and flexibility is the closest to what I remember from the instruments I started on in the 1960s. Highly recommended!
Feel- Sound- Flexibility (not too stiff with medium high action)- Durability (I've never broken a string). Some may find them pricey but I'm of the "get what you pay for" school of thought.
By Jeff M.
Flourtown PA
Fantastic product, fantastic vendor
March 7, 2021
Normally I’m a LaBella 1954 Original Vintage guy, but my two Fender ‘57 AVRI Precisions just don’t have the necks for those things. JF344s are the proverbial equal and opposite strings. The tension and corresponding feel are light and soft. Switching has been like going from a steel string acoustic guitar to a classical, which I mean in a good way. But here’s the ‘equal’ part: like the bridge-cable LaBellas, the TIs sound terrific, and they only get better with age. If you’re thinking about them...go for it. You’ll be glad you did.

And of course, juststrings.com has been my go-to string supplier for a long long time. They’re the best.
Great sounding Low tension is easy on instrument, hands Aging only improves strings Price is admittedly daunting
By Willy F.
Pittsburgh, PA
These things are expensive, but worth every penny!
February 27, 2021
I did a demo of these strings on YouTube. They’re dark, tubby, and PERFECT for old school growl at a medium/light tension. They feel great, sound great, and last forever.
Play great, Sound great, last forever.. Expensive, but it?s one purchase you may never have to make again.
By Zorro
Nice round bottom end sound
December 31, 2020
I used to play the stand up bass. I have been using these strings for years, after trying many others, as these strings are the closest I've found to the sound of a stand up bass with gut strings on a late sixties Precision. They produce that nice round, full bottom. They do not require high string tension witch is easier on the instrument and the player. I think that because of the lower string tension, it allows the string to vibrate more widely witch allows more overtones to be created producing that nice round, warm, full bottom end.
By John
Okay, but
December 22, 2020
Tried these strings on the recommendation of friends, and while I like them, for $80+ dollars I don’t think they’re really any better than the D’Addario Chromes I usually use. In fact, I think the E string is just too light. I’ll leave them on for a while longer, but I doubt I’ll buy another set.
Marginally better comfort than my usual strings E string is too light and I can?t get ?the beef? compared to my usual strings
By Chris
Great, low-tension flats
April 1, 2020
These are my personal preference when stringing one of my basses...low tension and provide a nice thump while still ringing out with a few electronic adjustments
None smoother feeling Expensive
Thomastik flat wound exelence.
May 13, 2019
hi y'all. I have searched and tried quite few brands including Fender, GHS, Ernie ball and settled on D'ddario chromes flat wounds which provided the best consistence tonnage yet the e string always produced that deep harsh & not clean "growl" so after reading reviews about the Thomastik nickel flats I decided to give them a shot in spite their cost and was egger to receive and try them. well, after put them on my vintage Fender p bass I discovered the bridge settle had to be adjusted so these strings don't rattle against the frats. to my surprise, the overall tone and consistency is by far superior to any flat wound strings I've tried plus the G string is now heard regardless where you press it...overall, Thomastik flats have a great worm and bright yet without that harsh growl and the tonnage yielded is somewhere in the middle so with the tone knob on a bass guitar will accommodate your style. last the Thomastik JF 344 strings A -D strings diameter is smaller then normal which feels weird indeed but, the required pressure exerted on the frets is substantially reduced resulting a much cleaner tone and that makes playing with these strings easier and improves playability yet will require some adaptation and getting use too and considering the warm clean tonnage I think its well worth it. I shell maintain vigilance with these strings to ascertain how long they maintain their awesome tone. to you guys I say, try a set and you'll find out that which I have. Avi
superior tonnage. less pressure required to press on the frets. G string brightness is superior & can be heard throughout the fret board. E string "growl" is reduced to minimum while producing a much better warm cleaner tone. playability is superior and without fret noise or other strings chatter. A - D strings are smaller in diameter which at first feels weird compared to normal gauge strings sets. the cost of Thomastk jazz flats is the reason bassists do not buy it according to many reviews.
By Dan
January 11, 2018
I've played these for years and they continue to be the perfect bass string for me. The light tension makes them easy to play and the sound is perfection. They are a bit bright when new, but once broken in they stay consistent, seemingly forever. You'll likely need to do a setup on your bass if you're coming from a higher tension string, i.e. back off on the truss rod adjustment.
By Adam
Great, but...
March 6, 2017
People rave about these strings! And don't get me wrong, I see why. The tone is incredible. My only complaint is that they are SO THIN! How do you people handle it? The low tension is something that one can get used to... but a .43-.100 gauge string is essentially useless for me as soon as the drummer comes in. (It's not like I'm playing heavy metal or anything... mostly Jazz, Funk, Latin styles) If TI made a heavier gauge of these (.50 .70 .85 .105), they'd be the perfect string, IMHO.
By Doug Y.
J344 Strings
February 11, 2017
I have a Fender Custom Shop NOS 64 Jazz Bass. I have not been happy with any strings. No bottom and punch. I tried my first set of J344 strings last night at a gig and my bass finally came to life! We had to play for 2.5 hours without a break and my hands feel great! What a fantastic surprise. Even the other guys noticed the improved sound of the bass! I'm sold!!
By Kenneth G.
Thomastik-Infeld nickel flat wound bass strings
May 12, 2015
Being on a tight budget I had a hard time justifying spending this much on strings. Got an email with a discount code for these and ordered them. They still were expensive but they are worth the money. The first song I played with them in the band, the guitar player commented on how good they sound. I love the sustain, tone, ease of playing, and they even seem to be louder than other strings. Had to loosen up the truss rod as the strings I had on had more tension. Also had to adjust the intonation. It was all worth it, these strings are my favorite so far. I'm using a Carvin LB70.
By Al F.
Excellent strings!
May 2, 2015
I had these on my Squire VM Jazz bass, and though they sounded nice, due to fret issues they buzzed too much. I took them off but saved them. A couple of months later, I put them on an SX Ursa 1 bass, and they are AWESOME! That bass has better frets if you can believe that .... no buzzes unless I dig in too much (I like low action). The D string sounds a bit dead, maybe because I took them off the other bass, but it's not too bad. I'll be ordering a single .056 very soon, and these strings are staying on this bass! Be sure to bend before you cut, though, to avoid killing your strings! And don't keep moving them from one bass to another :)
By Calvin N.
Good on Breedlove Acoustic Bass
March 19, 2015
I have a Breedlove acoustic bass that has a pinless bridge that every string won't fit. It came with D'Addario acoustic bass phospher bronze strings and I hated them all the fret noise etc.... I just happened to have Thomastik JF344 I put them on so much nicer because I was looking for a upright bass sound. But I kept hearing about how great tapewound strings sound on the acoustic bass so it kept bugging me to try some out so I ordered the GHS tapes and they would not fit the bridge where the string meets the ball. So I was told that the LaBella tapes would fit so I got those and they did fit. I was disappointed some how I lost the upright sound and too bright for my liking so I put back on the Thomastik Jazz JF 344 and I'm so glad I did. I got back the rich warm sound to be honest in my opinion there was no comparison. The only downside is you do lose unplugged volume using the flats but I'll live with that cause I love these strings on my Breedlove bass and they fit through the bridge perfectly. I also had to put quite a bit of relieve in the neck do to the low tension these strings have but now it plays beautiful and sounds good. What I hear unplugged I hear plugged in and these strings are expensive but it should be along time before I need to change them. Thanks!
By Cg
Killer strings
December 23, 2014
Have had these on a war moth all maple jazz for over six years. They are the most versatile string I've ever used. From blues to metal to punk to fuzzed out with envelope filters. They do it all well.

Killer fundamental if you play close to the fret board. You can get a great teaser type tone.

Oh and you can bend them like crazy.

Great vibrato as well.
By raqcoon r.
smooth feel & tone
June 2, 2014
Previously not a huge flatwound player, but owning both a slap & fretless bass spawned marked separation of tone & style. Of course, these are strung on the fretless resulting in good clean aural enhancement. The only other experience with flats were black nylon which sounded rubbery. These steel flats are not rubber, obviously, and being that Thomastik is pricey, presumably because of quality (although commerce has its influences), this could be as good as it gets.
By Jonathan S.
You must try these strings!!!!
February 7, 2014
I've never been a fan of flat wound bass strings...especially on fretted instruments. I gave these a try on my fretless Zon and loved them. On a whim I tried them on my fretted Zon Mosaic J bass and BOOM! All the crunch and character of a vintage instrument, but with exceptional clarity and response. I will use these for the rest of my life. I've tried countless different brands of strings over the years, and while there are noticeable differences between them, none provided a fundamental transformation in the way a bass sounds and feels like these do. You owe it to yourself to give them a try.
344 jazz TI
July 13, 2013
Fender deluxe jaguar bass - if u like to quiet the feedback monster and made it into a masterpiece. Invest a bit more. SWEET.
By Mark L.
TI Nickel Flats 043 - .100, JF344
June 17, 2013
These strings sing beautifully on a J. Makes the tone knob about 20 times more useful: I'm able to dial in pure dub thumb to punchy rock growl. Highly recommended.
By Brandon M.
I have to gush...
June 5, 2013
After 20 years of playing bass, I've found my absolute dream strings. I slapped a set on a MIA Jazz about a 2 years ago, after some really tight tension rounds and didn't bother to set my bass up correctly. I thought they were meh and ended up selling the bass with the TI's on it.

I recently put together a Warmoth Jazz with an alder body and ebony fingerboard and thought I'd give them another try (along with a good setup) and am so glad I did: I got the action nice and low across the neck with zero buzzing (and I'm an aggressive player) and the smooth, supple feel exudes the most buttery tone with a minimal amount of exertion.

Point being: Make sure you really dial in your setup when transitioning to these strings before kicking them to the curb (I ended up having to relieve the neck way more than I thought I'd ever have to). They can be a bit finicky at first, but are well, well worth the effort.
By Craig K.
TI Jazz Flats
April 14, 2013
Best flat wound strings I've ever used.
I put them on all my basses. Nice bright tone for a flat wound and they last forever.
Love em!
By Jazz B.
Thomastik-Infeld Electric Bass Nickel Flat Wound Roundcore 4 String, .043 - .100, JF344
February 13, 2013
Just awesome! Love 'em.
By Bob C.
Thomastic Infield Flat Would Strings
December 16, 2012
The only flatwound with a great singing sustain and an incredible fundamental.
Worth the price.
By Mike
Excellent strings
December 11, 2012
I've yet to find a better set of flats. Great voice, not too stiff, natural-feeling.
By Marcel
TI Flats
October 16, 2012
Wow these strings are fantastic! Very bright and they cut through any mix easily! Highly Recommended
By Marcel
TI Flats
August 28, 2012
Fantastic strings! These strings are so bright and clear! It can easily cut through any mix, and it's easy on the hands! Highly recommend.
By Bruce
Best sounding flatwounds I've ever used!
June 24, 2012
Can't understand how these strings could have been rated poorly by anyone. Lively, smooth, well balanced. These strings have absolutely transformed by old Ric 4001!
By Shawn
May 25, 2012
These overly expensive strings were a tremendous disappointment. The feel is rough and they buzz horribly. I wish I hadn't taken a chance on these and bought the Pyramids instead.
By John D.
April 6, 2012
I have two ratings for this:


- I've been using the JF344 set for about 3 years now. The tone and feel are wonderful. Very smooth to the touch. They seem to last a very long time. I still have the original set and they are still going strong. You can get real close to the Jamerson/Babbit tones of the Motown days.


- For me the only down side is that they feel floppy. It would be great if TI would release a set with .105-108 for the E-String. I would even buy a 5 or 6-String set if they had a larger string available. It seems they only offer .100's for all sets except for short scale.

Outside of this, I would still highly recommend them!
By Justin B.
T-I Flats
March 27, 2012
Everyone's review are so complimentary regarding the sound quality and performance that I had to try 'em. Stunning! I've tried the majority of string brands available over the past several decades. These DO Not Disappoint. Yeah, the price is high, but you'll know where that extra $$ went when you string 'em up and plug yerself in. On a Gibson Thunderbird, these are Killer!! If you've ever played or do play with a pick occasionally like I do, these will impress. The sound cuts through to the crowd. You don't get "muffled" by the rest of the band. These are not some "old-fogy" strings, they are precise tools to create the demanding criteria you'd dream of in a performance. Do it!






1st G

Nickel Flat Wound Roundcore



2nd D

Nickel Flat Wound Roundcore



3rd A

Nickel Flat Wound Roundcore



4th E

Nickel Flat Wound Roundcore




Jazz Electric Bass

characteristics: smooth, warm balanced

"E-Bass Jazz Series are strings with extended durability and high output. A highly flexible steel core gives the string a balanced feeling and a special character. The overall sound characteristics can be described as very close to the double bass.



Founded in 1919, one of the world's largest manufacturers of strings for musical instruments has applied 76 years of experience to develop a new generation of strings.


Vienna, music capital of the world


Our strings are handmade by highly qualified specialists. With our extensive quality control via computer and signal processing equipment, we have successfully combined Old World craftsmanship with state of the art technology.


The results of our research and our scientific approach to string manufacturing -- based on cooperation with musicians and scientists -- have led to the creation of a new line of guitar strings that is exactly what professionals are calling for.


Guitar strings for creative musicians.

THOMASTIC-INFELD is the best kept secret in the music industry. Did you know that for decades most of the great jazz and classical guitar players have chosen THOMASTIK-INFELD strings? Old World quality and experience, combined with the most advanced modern technology available, give you creative tools to meet the highest standards of performance. Perhaps the time has come for you to discover what a chosen few have know for years? THOMASTIK-INFELD cares about the needs of professionals and amateurs. Worldwide."



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