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Thomastik-Infeld Electric Bass Nickel Flat Wound Roundcore 5 String, .043 - .136, JF345

Thomastik-Infeld Electric Bass Nickel Flat Wound Roundcore 5 String, .043 - .136, JF345
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15 Reviews
93% (14)
7% (1)
0% (0)
0% (0)
0% (0)
13% Recommend this product (2 of 15 responses)
By Ron
August 5, 2021
Sound I’ve looked for a long time! Well worth the money!
Great customer service NONE
By David
Sacramento, California, USA
T-I bass strings highly recommended!
February 17, 2021
These strings are simply exquisite in tone, evenness of gain, and playing feel. The low B string is especially lovely. They are worth the price, and I will buy them repeatedly for my Fender American Elite Jazz Bass V.
Tone, gain, playing feel. None.
By John C.
Thomastik-Infeld Flat Wound Strings
December 6, 2017
I have a set of these on my Schecter Stiletto Studio 5 Fretless Bass. First off, the bass is grand, and having a set of these on the bass drew the attention of sound guys in a hurry. the low ends rumble deep and are throaty, the high ends are where you want them to be as well. Since I have 5 strings, I can stay at lower registers where the rest of the band and sound people would like me anyway, rather than getting lost in the mid-ranges as happens with bass players at times. But even if I do venture "up there a ways", these strings have a richness in tone that wonderfully resembles a string bass, which is why I got these. I leave the tone texture to the sound people and ask for a simple playback in my monitors as the strings sound that good to me just plain. I have seen comments about longevity and I will confirm that these strings last a good long time. I have been playing mine for almost (yes count them) 5 years without a loss in tone! Worth the money! Strings are not good for slapping, no flat wound is, but I can get almost any other tone out of these strings I need. They boom! Oh! And that low B string! It is almost out of this world. Sometimes I will start on the low B at the 5th fret and play music from there as my E, the rest of the notes just richly boom! Superb set of all around strings, whole heartedly recommend them to anyone interested. I have bought two sets of these, one for me and one for a friend. The both of us will continue to use these. :)
By Thomastikuser
Extreme quality
May 18, 2012
The first thing I noticed when I put these on my Squier Vintage Modified 5, was that they are pretty bright. Full of piano harmonics. The B is great! It is surprisingly responsive. These buzz less that any other strings I have tried. They even eliminate buzzing from most high spots. The tonal balance is unbelieveable, but the tension balance is not too good. Due to its small gauge, the 70 A string will feel looser than the other string if you have a heavy touch. The only thing that bothers me is that the are coarser than most flats.
By Greg
April 28, 2011
Great strings! They live up to the hype. There are lots of reviews of these strings. I like the B string. They ARE a lighter tension than most flatwounds, since I bend notes sometimes in phrases it doesn't bother me at all, coming from roundwounds the TJIF's feel the same tension-wise, coming from standup bass they are way loose. Don't be afraid. These strings are in a class by themselves.
By Woody
Thomastik-Infeld Electric Bass JF345 strings
April 16, 2011
I have now replaced my original string preference with the Thomastik-Infeld Electric Bass Nickel Flat Wound Roundcore 5 String, .043 - .136, JF345 strings.
- At this point, I expect these to remain my preference on the Fender American Deluxe 5-string Jazz base going forward.
By RandyT
Thomastik-Infeld bass strings
January 26, 2011
I purchased the strings after playing a friends bass. they sounded and felt great on his guitar. i have a Stingray5 and i hated the way they made my guitar sound and feel. I went back to Elixir's after 1 night of playing the T-I's. nothing ventured nothing gained. just my opinion.
By Randyt
TI flats
January 14, 2011
A very well built flat wound, good sound...allows for lower action, faster runs, decent tone, not a whole lot of character...great B string.,
By Fretless T.
Thomastik-Infeld JF345
December 26, 2010
These are not your typical flatwound string. They are very flexible and feel like they are lower tension than they are (through they are relatively low tension). They have more movement, and consequently a very different sound (and somewhat different feel). They resemble an acoustic upright bass gut or nylon string in feel and tone. The result is a unique warm sound that brings out the best in top of the line instruments (I use them on both my fretless Pedullas) and in production instruments (I used them on my fretted Fender too). And don't worry about the low B! It's great!
By Harold M.
November 9, 2010
The reasons that I purchase Thomastik-Infeld bass strings are many. Here are the first three. 1 they play in tune with less tension. In essence it's a "soft string".

2 they last a very long time. 3 they make them so that I can use them on my fretted basses and my fretless basses. If you want to hear more it will cost you a set of strings.

H. Moore
By Irene F.
September 27, 2010

I'm a long time user of both DR, and Thomastik strings. Thomastik JF-flats are the only flatwounds I use. They are simply the best strings I've ever played.
I would rate all these products five-stars.
By Joey D.
Thomastik-Infeld Flats
May 26, 2010
These strings are easily the best I have ever used. It's been 4 years since I used flats, and these strings make me wonder why I changed to roundwounds. These give my bass an incredibly warm tone. It's not too thumpy either. These strings are great for Motown, Jazz, Blues, etc. I have found my sound with these strings. I'm not using any other strings. They are definitely worth the price.
By Steve A.
T-I Jazz Flats
March 22, 2010
I have these strings on two of my bass guitars and am quite happy with them. They sound great and are very well made.
By Joe L.
Thomastik-Infeld Flat Wound Bass Strings
December 3, 2009
The strings give a mellow sound to my bass, much appreciated as a Blues player. I've been using them for about 5 years and have them on all my electric basses.

Long lasting too, worth the money.
By kevin
ti jazz flats
November 29, 2009
Amazing strings. Provides the solid fundamental of flats, very warm and woody. Also provides the growl of rounds when you dig in. Very loud, high output strings. Perfect for rock and r and b and for pick work. Not great for slap, but then again, no flats are. You owe it to yourself to try these strings, you haven't heard a b string until you have heard this one!






1st G

Nickel Flat Wound Roundcore



2nd D

Nickel Flat Wound Roundcore



3rd A

Nickel Flat Wound Roundcore



4th E

Nickel Flat Wound Roundcore



5th B

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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