Audio Distribution Circuit

P.O.Box 3073

Pinegowrie 2123

Gauteng South Africa

Tel: +27 11 838 0620

Fax: +27 11 838 0625 e-mail: [email protected]

www.soundfusion.co.za

Soundfusion (Pty) Ltd. Co. R eg . No . 19 94 00 95 87 0

TECHNICAL MANUAL

STEREO

AUDIO DISTRIBUTION AMPLIFIER

MODULE E-234

mailto:[email protected]

Stereo Distribution Amplifier Module E-234 GENERAL DESCRIPTION The E234 audio distribution card has been developed to complement the Soundfusion range of audio distribution amplifiers. The card evolved from the local industry standard, the Sound fusion E230. The card is essentially a one stereo input and 6-output distribution amplifier, but can be configured by means of jumpers to provide the following options: a) One stereo input, six stereo outputs. b) One stereo input, five stereo outputs, 2 mono outputs. c) One stereo input, twelve mono outputs. d) One mono input, twelve mono outputs. The two inputs are balanced, high impedance and feed through to the twelve output stages, which are each driven by a dual operational amplifier capable of driving 600 Ω loads. There is a level adjustment for left and right channels at the front of the card. Individual outputs are not adjustable. The circuit is fully balanced throughout and is powered by on board DC regulation as indicated by two LED’s at the front of the card.

Stereo Audio Distribution Amplifier – Module E-234 CIRCUIT DESCRIPTION Input: The two input stages consist of U1, U2 that provide a symmetrically balanced input. The low frequency roll-off point of 4Hz is determined by Cl, C2, R2, and R3. The high frequency roll-off is set by C3, R4 and C4, R5 at 80KHz. This point can be altered by increasing or decreasing C3 and C4. Output level is adjusted by P1 and P2. The output of this stage appears at J1 where it can be routed to the distribution buses, left or right. The left and right signals also feed U3 that acts as a virtual earth-mixing amplifier. This creates a mono signal that can be linked via J2 and J3 to outputs 6, or all outputs. Output: Each output stage consists of a dual op amp which is capable of driving reactive loads, as occur in long cable runs, to greater than +l2dBu. The input stages are directly coupled to the output stages, thus eliminating blocking capacitors, which are detrimental to the sound quality of the signal. This is possible due to the low offset of the devices used. There is no individual adjustment of the output stages but R29 (CH1L) may be changed to obtain a different output level if necessary. The output impedance is set at 20 Ω by R32, R33. Power: The card is supplied with unregulated ± 22 VDC at pins 2 and 3, which is fed to the adjustable voltage regulators Ql Q2. There is pre-regukition decoupling with C55, C56. The regulated voltage ± 16 VDC is determined by R123, R124, R125, and R126 and smoothed by C59 - C62. The LEDs LDI, L2 give on board indication of the DC condition.

Stereo Audio Distribution Amplifier – Module E-234

STEREO AUDIO DISTRIBUTION AMPLIFIER

MODULE E-234

COMPONENT LAYOUT

Stereo Audio Distribution Amplifier Module E-234Stereo Audio Distribution Amplifier Module E-234 Component Layout

+ +

+

+

C16

R39

R41R42

R36R35

R40

R37

R38

C15

C20

R55

R57

R58

R52

R51

R56

R53

R54

C19

C24

R71

R73

R74

R68

R67

R72

R69

R70

C23

C28

R87

R89R90

R84

R83

R88

R85

R86

C27

C32

R103

R105

R106

R100

R99

R104

R101

R102

C31

C36

R119

R121

R122

R116

R115

R120

R117

R118

C35

J3

C34

R111

R113

R114

R108

R107

R112

R109

R110

C33

C30

R95

R97R98

R92R91

R96

R93

R94

C29

C26

R79

R81R82

R76R75

R80

R77

R78

C25

C22

R63

R65R66

R60R59

R64

R61

R62

C21

C18

R47

R49R50

R44R43

R48

R45

R46

C17

C46 C48 C50 C52 C54

U15U13U11U9U7

C14

R31

R33R34

R28R27

R32

R29

R30

C13

C44

U5

C43

U4 U6 U8 U10 U12 U14C53C51C49C47C45C42

C62 C61 C60C59

C1 C2 C6 C7

J2

C12

R26R23

R24

R1R4

R2R3

R13R12

R11R14

C57

C58C3

C5

R7

R9

R6R5

R8

R10

C4

C8

C10

R17

R19

R16

R15

R18

R20

C9R21

R22R25

C11

C41U3U2U1

C40C39C38C37

P2J1P1LD2LD1

R128R127

R126R124

C55D1D2Q1Q2C56

R125

R123

ADA234

SOUNDFUSION

0V -V +V 1L 1R 2L 2R 3L 3R 4L 4R 5L 5R 6L 6R IN-L IN-R

Stereo Audio Distribution Amplifier Module E-234Stereo Audio Distribution Amplifier Module E-234


MODULE E-234

PARTS LIST

PARTS LIST

Audio Distribution Amplifier Module E-234

Reference Value Description

R 1 20k 1/4 W 1 % metal film

R 2-7 l0k 1/4 W 1 % metal film

R 8-9 lk 1/4 W 1 % metal film

R 10 120R 1/4 W 1 % metal film

R 11 20K 1/4 W 1 % metal film


R 18-19 lk 1/4 W 1 % metal film

R 20 120R 1/4 W 1 % metal film


R 25-26 5k1 1/4 W 1 % metal film

R 27-28 100R 1/4 W 1 % metal film

R 29 lk2 1/4 W 1 % metal film

R 30-31 2k2 1/4 W 1 % metal film

R 32-33 10R 1/4 W 1 % metal film


R 35-36 100R 1/4 W 1 % metal film

R 37 lk2 1/4 W 1 % metal film

R 38-39 2k2 1/4 W 1 % metal film

R 40-41 10R 1/4 W 1 % metal film

R 42 l0k 1/4 W 1 % metal film

R 43-44 100R 1/4 W 1 % metal film

R 45 1k2 1/4 W 1 % metal film

R 46-47 2k2 1/4 W 1 % metal film

R 48-49 10R 1/4 W 1 % metal film


R 51-52 100R 1/4 W 1 % metal film

R 53 1k2 1/4 W 1 % metal film

R 54-55 2k2 1/4 W 1 % metal film

R 56-57 10R 1/4 W 1 % metal film


R 59-60 100R 1/4 W 1 % metal film

PARTS LIST

Audio Distribution Amplifier Module E-234Reference Value Description

R 61 1k2 1 /4W 1% meta l f i lm

R 62-63 2k2 1 /4W 1% meta l f i lm

R 64-65 10R 1 /4W 1% meta l f i lm

R 66 10k 1 /4W 1% meta l f i lm

R 67-68 100R 1 /4W 1% meta l f i lm

R 69 1k2 1 /4W 1% meta l f i lm

R 70-71 2k2 1 /4W 1% meta l f i lm

R 72-73 10R 1 /4W 1% meta l f i lm

R 74 10k 1 /4W 1% meta l f i lm

R 75-76 100R 1 /4W 1% meta l f i lm

R 77 1k2 1 /4W 1% meta l f i lm

R 78-79 2k2 1 /4W 1% meta l f i lm

R 81-81 10R 1 /4W 1% meta l f i lm

R 82 10K 1 /4W 1% meta l f i lm

R 83-84 100R 1 /4W 1% meta l f i lm

R 85 1k2 1 /4W 1% meta l f i lm

R 86-87 2k2 1 /4W 1% meta l f i lm

R 88-89 I 0R 1 /4W 1% meta l f i lm

R 90 10K 1 /4W 1% meta l f i lm

R 91-92 100R 1 /4W 1% meta l f i lm

R 93 1k2 1 /4W 1% meta l f i lm

R 94-95 2k2 1 /4W 1% meta l f i lm

R 96-97 10R 1 /4W 1% meta l f i lm

R 98 10K 1 /4W 1% meta l f i lm

R 99-100 100R 1 /4W 1% meta l f i lm

R 101 1k2 1 /4W 1% meta l f i lm

R 102-103 2k2 1 /4W 1% meta l f i lm

R 104-105 10R 1 /4W 1% meta l f i lm

R 106 10K 1 /4W 1% meta l f i lm

R 107-108 100R 1 /4W 1% meta l f i lm

R 109 1k2 1 /4W 1% meta l f i lm

PARTS LIST

Audio Distribution Amplifier Module E-234Reference Value Description

R 110-111 2k2 1/4W 1% metal film

R 112-113 10R 1/4W 1% metal film

R 114 10K 1/4W 1% metal film

R 115-116 100R 1/4W 1% metal film

R 117 1k2 1/4W 1% metal film

R 118-119 2k2 1/4W 1% metal film

R 120-121 10R 1/4W 1% metal film

R 122 10K 1/4W 1% metal film

R 123-124 120R 1/4W 1% metal film

R 125-126 1k5 1/4W 1% metal film

R 127-128 2k2 1/4W 1% metal film

C 1-2 10µF 25V Electrolytic NP 2.5mm spacing

C 3-4 220pF 1 % Polystyrene axial 160V

C 5 6.8pF 63V Ceramic 5mm spacing

C 6-7 10µF 25V Electrolytic NP 2.5mm spacing


C 10 6.8pF 63V Ceramic 5mm spacing

C 11-12 10pF 63V Ceramic 5mm spacing


C 37-56 0.1µF 63V Ceramic 5mm spacing

C 57-58 10µF 25V Electrolytic 2.5mm spacing

C 59-60 0.1µF 63V Ceramic 5mm spacing

C 61-62 220µF 25V Electrolytic 5mm spacing

D 1-2 1N4007 Silicon diode

P 1-2 10k Bourns 3296P Trimpot

Q 1 LM317 Positive Adjustable Voltage Regulator

Q 2 LM337 Negative Adjustable Voltage Regulator

PARTS LIST

Audio Distribution Amplifier Module E-234 Reference Value Description

U 1-15 NE5532 Dual Low Noise Operational Amplifier

J 1-3 Jumper 2.54mm Molex

CON 1 64 way Edge Conn. DIN41612 90° male (AB row)



MODULE E-234

JUMPER CONFIGURATIONS

Stereo Audio Distribution Amplifier – Type E234


TYPE E234

CIRCUIT DIAGRAM



MODULE E-234

CIRCUIT DIAGRAM

Stereo Audio Distribution Amplifier – Module E-234Stereo Audio Distribution Amplifier – Module E-234

P.O.Box 3073Pinegowrie

2123 Gauteng

South Africa

Tel: +27 11 838 0620 Fax: +27 11 838 0625

e-mail: [email protected] www.soundfusion.co.za

Stereo Audio Distribution Amplifier – Module E-234 SPECIFICATIONS

Input impedance > 10k

Output impedance > 20 Ohms

Gain range (pot) -12dB to +12dB

C.M.R.R. (ref + 6 dBu input) 100 Hz > 60dB

1 kHz > 62dB

10kHz > 62dB

20kHz > 62dB

Signal to Noise (ref + 6 dBu input) Unweighted < -90dB

(30 kHz BW)

“A” weighted < -100dB

Frequency Response 10 Hz to 20 kHz < -0.05dB Maximum Output (unity gain/ <0.1%THD) Amplifier driving 500 meters screened cable terminated in 10kOhms. 20 Hz - 20 KHz > +22dBu Amplifier driving 500 metres screened cable terminated in 600 Ohms 20 Hz -20 kHz > +18 dBu Total Harmonic Distortion 10 k Ohms and 600 Ohm load at +6 dBu (Unity gain) 20 Hz - 50 KHz < 0.004 % Total Harmonic Distortion. Amplifier driving 500 meters screened cable terminated in 10 kOhms and 600 Ohm load at+l8dBu (Unity gain) 20 Hz -20 kHz < 0.006 % Intermodulation Distortion 600 Hz and 7 kHz 20 Hz - 50 kl-fz < 0.003 % Cross talk 10Hz > - 130dBu 50 kHz > -75 dBu

Documents

Audio Distribution Circuit