background image

 
  1 = Power connection (+) plus only over fuse. 
  2 = Power connection (–) minus, autobody and/or central ground. 
  3 = Remote connection for remote signal from CD-radio. 
  4 = Remote output for amplifier 
  5 = Remote output for remote 
  6 = Input „INPUT FRONT“ for signal input from CD-radio  
  7 = Input „INPUT REAR“ for signal input from CD-radio  
  8 = Singal output „OUTPUT“ for amplifer to be driven. 
  9 = Switch for „INPUT“ HIGH = balanced or LOW = unbalanced 
10 = Switch for input sensitivity 
11 = Switch for high-pass operation FRONT 
12 = Switch for high-pass operation REAR 
13 = Switch for low-pass operation REAR 
14 = Switch for mono operation REAR 
15 = „GAIN“ control for adjustment of input sensitivity for „INPUT FRONT“. 
16 = Control for cut off frequency

 

high-pass FRONT 

17 = Control for cut off frequency high-pass REAR 
18 = Control for cut off frequency low-pass REAR 
19 = Control for phase shifter REAR 
20 = „GAIN“ control for adjustment of input sensitivity „INPUT REAR“ 
21 = Control function: LED red = preamplifier in operation 
22 = LED-display for clipping FRONT / REAR channels 
23 = Signal output „LINE OUT“ for subsequent amplifiers 
 
 

Installation

 

KW 4V8

 
Fasten amplifier to a suitable, well-ventilated location in the vehicle, if possible to the auto body,

 

with included 

sheet metal screws and insulated washers. 
 

Caution:

  Clamp the negative pole of the battery before working on connections.  This work requires expertise 

and should be performed with careful consideration to the relevant safety regulations. 

 
Attach red cable with minimal diameter of 1 to 1.5 mm2  directly to the positive terminal (+) of the battery or the 
central positive point of the HiFi unit and run to the amplifier. Make absolutely certain that the main electrical 
cable is secured with a safety cable (see below). 
 
Connect the free end of this power cable to the red “12V” cable (

1

) of the preamplifier by means of a luster 

terminal. 
 
Connect black cable with small diameter of 1 to 1.5 mm2 directly to the autobody or to the central ground of the 
HiFi unit and connect to the black cable “GND” (

2

) of the preamplifier by means of a luster terminal. 

 
The total electrical consumption of the complete audio system must be calculated to determine the appropriate fuse 
to be employed. Therefore, the total electrical requirements

 

of each audio device must be considered. Review 

manufacturers data for each individual unit and add together to determine total consumption (include fuses with 
Amp data)

.

 The resulting sum is the total electrical consumption in ampere and corresponds to the fuse 

requirements.  The fuse must always be inserted into the main power cable directly behind the battery (+). 
 

Summary of Contents for KW 4V8

Page 1: ...aftwerk Amplifier KW 4V8 4 Channel Preamplifier Part No 271029 Please read installation manual carefully before beginning installation RAC GmbH Co KG P O Box 12 25 74899 Bad Rappenau Germany Telephone...

Page 2: ...of its products Work to Vehicle Do not begin operation of vehicle before all components of the loudspeaker system and the amplifier are firmly and securely in place Many parts when unsecured can beco...

Page 3: ...Mode REAR Frequency Response 14 Figure 5 Bandpass REAR Mode 15 Bandpass REAR Mode Frequency Response 15 Figure 6 Power Provision Indications 16 Determining the Central Ground 16 Principal Connection D...

Page 4: ...he amplifier only in the car interior or trunk Do not install the amplifier in the engine compartment The amplifier should not be placed under pressure or covered Make certain that no foreign particle...

Page 5: ...sible use the included fuse Always follow the accompanying instructions when connecting an external condenser We do not accept responsibility for damage caused by the inappropriate use of an external...

Page 6: ...electrical circuits High tech semi SMD built structure with low coupling wiring Interference proof certified in accordance with E Norm Technical Specifications Total Harmonic Distortion THD N 0 05 Sig...

Page 7: ...7 Front View and Controls KW 4V8 Figure 1 Controls...

Page 8: ...ith included sheet metal screws and insulated washers Caution Clamp the negative pole of the battery before working on connections This work requires expertise and should be performed with careful con...

Page 9: ...tentiometer GAIN 20 for REAR and the SENSITIVITY 10 switch from 400 mVolt MAX to 4 Volt or 8 Volt MIN The LEVEL INPUT switch 9 should remain on position LOW For subwoofer operation the preamplifier ca...

Page 10: ...for subsequent amplifiers OUTPUT Amplifier Output The amplifier over which the KW 4V8 preamplifier is to be fed is connected by means of a RCA cable over the outputs OUTPUT 8 F RCH front right F LCH f...

Page 11: ...ve loudspeaker systems This mode of operation is therefore suitable for all kinds of loudspeakers and loudspeaker systems in which frequency separation occurs via passive crossovers Set HPF 11 switch...

Page 12: ...mechanical capabilities are strengthened Switch HPF 11 should be adjusted to setting x1 1 time or x10 10 times and the cut off frequency should be set by means of the potentiometer HPF 16 to between 1...

Page 13: ...Hz 5 kHz for the REAR channels Adjust level of subwoofer with controller GAIN 20 The phase position of the subwoofers should be checked against the basis system after start up of the complete system T...

Page 14: ...enting unnecessary load In choosing a subwoofer the load of the amplifiers must be suitable for the load limits of the subwoofer This precaution prevents a premature distortion in the bass range and t...

Page 15: ...es and cut off frequency of the highpass frequency from which the loudspeaker should play HPF 17 to between 15 Hz 500 Hz and or 150 Hz 5 kHz for the REAR channels by means of a potentiometer Set switc...

Page 16: ...stort when long cable lengths cause a premature voltage drop This can be prevented by using a cable with a large diameter and minimizing the transition resistance at the connection points Appropriate...

Page 17: ...ange Output is already heated in the no load operation or in the smallest capacity range by high frequency distortion The preliminary input stage of the amplifier cannot differentiate between music an...

Page 18: ...18 Figure 7 Principal Cable Diagram...

Page 19: ...l as to the warranty repair A warranty claim does not exist if defects resulted from inappropriate assembly transport damage mechanical damage or foreign interference Accidents forces of nature or oth...

Reviews: