EB Cobalt Flats Tension Question

[Elmstreet]

The lead guitar player that just joined my band gets a discount on EB strings. I’ve never tried flats before and I’ve heard good things about the Cobalt flats so I thought I would give them a try, but I’m trying to decide on the string gauge.

I pretty much exclusively play D'Addario Balanced Tension rounds which are 45 - 107.

What gauge of EB cobalt flats should I try that will get the closest to my balanced tension rounds?

I couldn’t find a tension chart for the EB strings, but here is one from D’Addario of my 45-107 rounds that I like.

 

[jeff62]

I play the Cobalt .100’s and find them fairly balanced.

 

[Elmstreet]

I play the Cobalt .100’s and find them fairly balanced.

I appreciate the feedback. Have you ever tried the 45-105 set or have you always played the .100s?

 

[jeff62]

I appreciate the feedback. Have you ever tried the 45-105 set or have you always played the .100s?

Yep… Used to play the .105s exclusively. I found that I like the playability of the .100s even better and lost nothing sound-wise.

 

[jeff62]

And just fyi that Ernie Ball doesn’t publish tension charts, AFAIK. However, if you ask ChatGPT it makes its’ best guess based on what it can find on the interwebs….

For the .100 set, it’s
41 - 43- 48 - 42lbs (E A D G)

 

[michael_t]

I can get you the actual tension figures for the Cobalt Flats when I get home later tonight. (as in 3 hrs)

 

[HaphAsSard]

The lead guitar player that just joined my band gets a discount on EB strings. I’ve never tried flats before and I’ve heard good things about the Cobalt flats so I thought I would give them a try, but I’m trying to decide on the string gauge.

I pretty much exclusively play D'Addario Balanced Tension rounds which are 45 - 107.

What gauge of EB cobalt flats should I try that will get the closest to my balanced tension rounds?

I couldn’t find a tension chart for the EB strings, but here is one from D’Addario of my 45-107 rounds that I like.

View attachment 7286013

Tensions for a bunch of Ernie Ball Slinky Flatwound ("cobalt flat") sets were obtained by @michael_t through emails to the EB customer service, and posted here:
Light Gauge Cobalt Flats for 5 String?
Suffering from dead spots (especially with flats)? Try lower tension strings
The least-unbalanced custom set you could assemble would be 45-60-80-105, but 40-60-80-105 would only be a smidgen more so, and put total tension closer to that of the BT D'Addario set of rounds.

However, I'm not sure if and where single cobalt flats can be found. What to do then?

You could
- get three sets, the lightest (2815), the 5-string (2816) and the second-heaviest (2812; not included in Michael's posts);
- set aside the ones you want for the balanced, standard-tuned set (40-60-80-105);
- never use the 085
- use the rest as a lifelong supply for a 4-string tuned B-E-A-D or C-F-Bb-Eb, as follows
130 for the lowest, then
100 or (/and, when it goes dead) 095
070 (you'd have two) or/and 065
050 or/and (better if tuned to Eb than D) 045
for the occasional downtuning need.

 

[michael_t]

I can get you the actual tension figures for the Cobalt Flats when I get home later tonight. (as in 3 hrs)

Here you go...

Cobalt Flats 2813:

G 045 - 47.58 (lbs.)
D 065 - 52.51
A 085 - 49.12
E 105 - 41.78 (Total 191.00 lbs.)

Cobalt Flats 2815:

G 040 - 39.42 (lbs.)
D 060 - 43.80
A 070 - 32.58
E 095 - 32.50 (Total 148.30 lbs.)

Cobalt Flats 2816: (2814)

G 045 - 47.58 (lbs.)
D 065 - 52.51
A 080 - 44.49
E 100 - 37.72 (182.30)
B 130 - 35.35 (Total 217.65 lbs.)

Cobalt Custom Balanced Tension Set:

G 045 - 47.58 (lbs.)
D 060 - 43.80
A 080 - 44.49
E 105 - 41.78 (Total 177.65 lbs.)

 

[J-Bass RMR]

The lead guitar player that just joined my band gets a discount on EB strings.

I'll take for sets Cobalt Flats please...

 

[Yahboy]

I play the Cobalt .100’s and find them fairly balanced.

Me too..... Compare to other modern vibe Flatwound E string, like 9050L , ECB81 , even Group Flat III , Cobalt flat E string has best clarity , focus and fairly lasting tone.

 

[SonnyBassPlayer]

I have been playing EB's cobalts 45-100s for about 3 years now in D standard tuning, I chose them because they feel comfortable and light in that tuning; I could compare them to Rotosound swing rounds 40-100s in standard. I wanted strings that felt light but in a fully dropped tuning so I gained the missing tension of going down one step on all strings by moving to flats.
I could imagine them in standard being not overly hard but surely not too soft either

 

[Prodigus Filius]

Based on the tension specs provided by michael_t, here is a tension comparison of the EBCF’s with the same gauges of D’addario Chromes.

Ernie Ball Cobalt Flats

(G)

G2/.040/39.42lbf
G2/.045/47.58lbf

(D)

D2/.060/43.80lbf
D2/.065/52.51lbf

(A)

A1/.070/32.58lbf
A1/.080/44.49lbf
A1/.085/49.12lbf

(E)

E1/.095/32.50lbf
E1/.100/37.72lbf
E1/.105/41.78lbf

(B)

B0/.130/35.35lbf




D’addario CHROMES

(G)

G2/.040/37.80lbf
G2/.045/47.00lbf

(D)

D2/.060/48.10lbf
D2/.065/53.90lbf

(A)

A1/.070/35.46lbf
A1/.080/45.70lbf
A1/.085/51.70lbf

Note* .070 tension is extrapolated from CB070 D2 tension.

(E)

E1/.095/36.20lbf
E1/.100/40.30lbf
E1/.105/43.10lbf

(B)

B0/.132/38.70lbf