Knoll Stereo Amplifier 4K User Manual

Warranty  
Knoll Systems warrants MA1250 amplifiers sold in the USA and Canada by  
authorized Knoll dealers to be free of defects in materials and workmanship. This  
warranty extends for three full years from the date of purchase by the original  
consumer. Any products returned to Knoll Systems and found to be defective by  
Knoll Systems within the warranty period will be repaired or replaced at Knoll  
Systems decision, at no charge. Knoll Systems will not be responsible for the  
actual cost of installation or removal of the product, nor for any incidental or  
consequential damages. Some states do not allow the exclusion or limitation of  
incidental or consequential damages, so the above limitation may not apply to  
you. This warranty gives you specific legal rights. You may have additional legal  
rights that vary from state to state.  
4K and 6K Amplifier  
8 and 12 Channel Amplifier  
Installation Instructions v1.3  
Warning: To be installed and/or used in accordance with appropriate  
electrical codes and regulations.  
Description: The 4K and 6K are members of the long line of Knoll  
multi-channel amplifiers. Designed primarily for the custom install  
industry, they are used to power speakers with different or similar  
sources in multiple rooms. With 8 or 12 channels rated at 50 watts per  
channels at 8 ohms, these amplifiers pack some serious punch. Each  
channel has a gain control. The amplifier can be turned on and off via  
the front panel power switch or via the 12 VDC trigger. 4K channels 3-8  
can be linked to channel 1-2 individually using the link switches. 6K  
channels 3-12 can be linked to channel 1-2 individually using the link  
switches. 4K and 6K amplifiers designed to meet the amplifier needs of  
custom installed systems where high-quality sound is a specific  
requirement.  
Specifications: 4K (eight channel)/6K (twelve channel)  
Inputs  
8/12 Gold RCA jacks with adjustable gain  
50k ohms  
Input impedance  
Outputs  
Gold 5 way binding posts  
Output power  
Peak output power  
Ideal impedance  
Frequency response  
S/N ratio  
50 watts RMS per channel (8 ohms)  
100 watts per channel (8 ohms)  
4 - 8 ohms  
10 Hz - 40 kHz +/- 1dB (1w)  
over 105 dB A weighted (50 watts)  
less than 0.1% 20 Hz to 20 kHz  
less than 0.01% 60 Hz 7 kHz 4:1 (SMPTE)  
12 VDC 35mA on 3.5mm mono jack  
17" x 3.5" x 11.5" (432 x 89 x 292mm)  
quiet 26 dBA  
Key Features:  
1. Size efficiency. The 4K has eight power amplifiers and the  
6K has twelve power amplifiers each in one 3-1/2” high  
enclosure. Each power amplifier channel can deliver 50 watts  
RMS into an 8-ohm load.  
2. Automatic protection circuitry. Each amplifier channel is  
individually and fully protected against low impedance,  
overheating, overloading, overvoltage and undervoltage. The  
protection circuitry automatically restores the amplifier channel  
as soon as its parameter returns to the safe operating area.  
3. Individual input gain adjustment. Each channel features  
an rear chassis input gain adjustment pot to adjust each channel  
for gain and speaker sensitivity variations.  
THD distortion  
IMD distortion  
Trigger control  
Dimensions  
Fan Noise  
Power  
550/750 watts at 117 VAC or 230 VAC  
21 lbs (9.5 kg)  
Weight  
Note: Specifications subject to change without notice.  
4. External power on/off. The 4K and 6K can be turned off  
and on by external controllers using the 12 VDC trigger jack.  
5. Stackable 17" chassis with 19” EIA rack version option.  
6. Link Feature. Certain installations require that some or all of  
the stereo channels play the same content. Instead of using Y  
cords, "link" cascades any or all of channels 2-6 to channel 1  
(l/r) on model 6K. With 4K link channels 2-4 to channel 1 (l/r).  
Knoll Systems  
145 Tyee Drive Point Roberts, WA 98281  
12140 Horseshoe Way, Richmond, BC V7A 4V5  
Tel: (604) 272 4555, fax (604) 272 5595  
Made in Canada  
 
Knoll Systems service information  
The 4K and 6K amplifiers do not contain any user serviceable parts  
inside. If you suspect a problem that may require servicing, contact us  
Installation  
Installing the 4K or 6K should be relatively easy. With a bit of  
planning, the 4K or 6K will give trouble free service for years.  
1. The most important consideration when installing the  
4K or 6K is cooling. The 4K or 6K has a lot of power packed  
into a small chassis size. When installing it in an equipment  
stack, it should be the top component. It needs at least 3"-5" of  
space above the amplifier to allow for adequate convection  
cooling.  
Troubleshooting: If a problem is encountered with the 4K or  
6K, the most expedient procedure is to locate the problem and if  
possible repair it before requesting service. Be sure to carefully  
check other system components such as controllers, CD players,  
volume controls, wiring, speakers, etc. that may be at fault.  
Problem  
Power LED does  
Action  
2. Amplifiers should always be the top components in system.  
1. Check that the amp is plugged in.  
not light - no sound 2. Test the AC outlet with a lamp.  
3. If remote on/off is used, check that  
3. If 4K or 6K channels frequently shutdown due to overheating,  
install a fan directed up from the amplifier bottom center.  
the trigger voltage is at 12 VDC.  
4. Check 4K or 6K power button is on (in).  
4. Never operate the amplifier on its side, as the cooling  
potential drops significantly when operated on the side.  
Sound cuts out  
1. Verify speaker impedance is 4-16 ohms.  
Changing speakers may be required.  
2. Check if the amp feels hot. If it's  
hot increase cooling - see Installation.  
5. Connect the 4K or 6K inputs to the source component outputs  
with good quality, short as possible RCA jack cables. Connect  
each channel individually.  
Sound is distorted  
1. Turn the volume down.  
6. Connect the 4K or 6K speaker outputs to speakers using good  
quality speaker wire. Minimum 16 gauge copper wire is  
recommended with 14 gauge minimum for runs over 30' (10m).  
2. Check speakers for damage.  
3. Check inputs for proper levels.  
4K or 6K gain and source output level  
may have to be adjusted.  
Note: Ideally the 4K or 6K likes 6-8 ohm loads. Connecting  
to 4 ohm loads won't hurt the 4K or 6K but those channels  
connected to 4 ohm loads may occasionally shutdown due  
to overloading. Never connect the 4K or 6K to less than 4  
ohms.  
4. Speakers may be less than 4 ohms.  
MA1250 does  
not turn off  
1. Push 4K or 6K power switch off (out)  
2. If trigger is being used, power switch  
needs to be set to off (out) position  
or amp is on all the time.  
7. Individually adjust the channel gains as required. Ideally, all  
gains are fully on (fully clockwise).  
3. Try disconnecting trigger jack.  
Trigger does not  
work  
1. Measure trigger voltage with a volt  
meter. It needs to be 11-15 volts DC  
to work (current is about 35mA total  
per amp). See page 5 for details.  
8. Make sure the speakers in each room are connected in phase  
with the amplifier + going to the speaker + . Out of phase  
speakers give unstable imaging and poor bass response.  
9. Connect trigger if being used to a 12 VDC source (about  
35mA) using a 3.5mm mono jack. 5 VDC triggers will not work.  
Speaker pops when 1. Speaker may need resistor placed  
amp turned on or off  
across terminal. Suggest 2k0 1/4 w.  
Discharges speaker internal cap.  
 
10. Connect the AC power into an outlet that supplies at least  
six amps (750 watts) dedicated to each 6k (four amps to 4K).  
Caution: Never listen to sound that is distorted. If distorted  
sound is heard, turn the volume down immediately or speaker  
and/or amplifier damage could occur that is not covered by the  
warranty. If this problem persists, contact your dealer.  
The trigger is 12 VDC (35mA per 4K or 6K) via 3.5mm  
mono jack. 5 VDC trigger outputs will not work. To  
connect the trigger to a receiver use a 12 VDC power  
supply (we suggest Knoll PS1202 power supply with an  
adaptor). Plug the power supply into the switched outlet  
on the rear of the receiver. Connect the 12 volt wire to a  
3.5mm mono jack. Plug the jack into the rear of the 4K or  
6K. 12 VDC polarity is not important. Make sure the  
amplifier power switch is off (out). When the receiver is  
switched on, the 4K or 6K amplifier is switched on.  
User adjustments and service: Other than a gain or volume  
adjustment, there are no user adjustments on the 4K or 6K.  
Your installer may make certain gain level adjustments on the  
rear panel.  
Caution: The 4K or 6K contain no user serviceable parts, so do  
not attempt to open or repair the 4K or 6K. Refer servicing to a  
qualified technician only or contact the factory for information.  
12 VDC  
Trigger  
Output  
Output  
Output  
L+  
L-  
L-  
L+  
L+  
L-  
L-  
L+  
L+  
L-  
L-  
L+  
Input  
1
Input  
3
Input  
5
2
4
6
L
L
L
2
1
5
6
3
4
R
R
R
120 VAC  
8 Amps  
R+  
R-  
R-  
R+  
R+  
R-  
R-  
R+  
R+  
R-  
R-  
R+  
1L 1R 2L 2R  
3L 3R 4L 4R  
5L 5R 6L 6R  
Gain  
Gain  
Gain  
6K Amplifier  
Caution: NEVER connect the 4K or  
6K to impedances less than 4  
ohms or amplifier damage not  
covered by the warranty may  
occur.  
The Link button is normally set to the in  
position to give all six stereo inputs individual  
sources. When the Link button is set to the  
out position, that input Left/Right is linked or  
cascaded to input #1 (without the use of Y cords). Any or  
all combination of linked inputs 2 to inputs 6 are possible.  
When all inputs are linked to input 1 the input impedance  
is about 4000 ohms.  
 

Indesit Washer Dryer WG1033TG User Manual
Ingersoll Rand Water Pump NM2202B X User Manual
Jacuzzi Hot Tub BE60 User Manual
JL Audio Car Speaker TR600 CXi User Manual
John Lewis Ventilation Hood JLBIHD105 User Manual
JVC Camcorder GR DV 3 User Manual
JVC Home Theater System SP PWA55 User Manual
JVC VCR HR DD840U User Manual
Kensington Computer Keyboard K62064A MSRP User Manual
Keys Fitness Treadmill 502t User Manual