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sw

Brian May Treble Booster

Here’s a simple treble booster based on the Brian May model. A single

medium-gain transistor with low-value caps on the input boost the treble

part of the signal. The original used a BC182L transistor but the 2N5087

works just the same. This circuit is very close to the original Dallas

Rangemaster.

beavis board project

A100K

Volume

in

out

Mods!Try different NPN transistors to see how more or less gain affects the sound. Be

sure to check the pinouts!

Increase C1 and C3 to 100nF for a full range boost.

Q1

2N5088

E

C

B

R2

100KΩ

R3

120KΩ

C3

47nF

VR1

A100KΩ

(Vol)

C1

4.7nF

9 volts +

Input

Output

4.7

nF

47n

f

R4

1KΩ

R1

100Ω

R6

6.8KΩ

R5

22KΩ

C2

1nF

R7

2.4KΩC4

47uF1KΩ

100Ω

100KΩ

1n

f 2N5088

E

B

C

47uf+

120KΩ

6.8

KΩ

22KΩ2.4

KΩ

revision: 1.0 ● 28 may 2008 ● © 2008 beavis audio research