Frequency Chart

Following is a frequency chart in Hertz. It will help you understand how to control EQ on amps and pinpoint problem notes and feedback frequencies. The bold  numbers correspond with the open strings of the bass. Each vertical row to the right is an octave higher. For example, 41.2 Hz is the low E string on your bass. 82.4 Hz is the first E on the D string. 164.8Hz is the first E on the G string, etc. A440 is the note that most tuners and pitchforks use as a standard tuning note

A
27.5
55.0
110.0
220.0
440.0
880.0
1760.0
3520.0
7040.0
Bb
29.1
58.3
116.5
233.1
466.2
932.3
1864.6
3729.3
7458.6
B
30.9
61.7
123.5
246.9
493.9
987.8
1975.5
3951.0
7902.1
C
32.7
65.4
130.8
261.6
523.3
1046.5
2093.0
4186.0
8372.0
C#
34.6
69.3
138.6
277.2
554.4
1108.7
2217.5
4435.0
8869.9
D
36.7
73.4
146.8
293.7
587.3
1174.7
2349.3
4698.6
9397.3
Eb
38.9
77.8
155.6
311.1
622.3
1244.5
2489.0
4978.0
9956.0
E
41.2
82.4
164.8
329.6
659.3
1318.5
2637.0
5274.1
10548.2
F
43.7
87.3
174.6
349.2
698.5
1396.9
2793.8
5587.7
11175.4
F#
46.2
92.5
185.0
370.0
740.0
1480.0
2960.0
5919.9
11839.8
G
49.0
98.0
196.0
392.0
784.0
1568.0
3136.0
6271.9
12543.8
Ab
51.9
103.8
207.7
415.3
830.6
1661.2
3322.4
6644.9
13289.8