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Adequate  ventilation is a primary consideration when

installing any high power amplifier, because of its appreciable

heat output. Cool air is drawn in through the foam filters on the

sides, and the warm exhaust is to the rear. Make sure this flow is

not impeded, and do not allow the system to work in a closed

box. The 

filters

 must be kept clean  - just slip them out, wash

them,  and squeeze dry. Replacements are available from the

Hafler Company, but if you choose to obtain them locally, make

sure  you use ‘open cell’

foam  for air conditioner filters.

Amplifiers supplied for overseas use with line voltages above

200 VAC use a different fan than those intended for 100   - 120

VAC. If conversion to the other line voltage range is indicated.

be sure the correct fan is obtained from the factory. See “AC

Line Connections for Overseas Use.”

The front panel is designed for mounting in a standard EIA

19”  wide rack, using four  #l10-32 screws and countersink

washers. It is sufficiently rigid to support the P505 safely. The

panel is slightly under the 7” height to allow clearance between

adjacent units. The feet may be unscrewed from the bottom to

facilitate such installation.

A power transformer of this size will radiate a noticeable hum

field, even though Hafler transformers are specially engineered

to  reduce this effect. If the amplifier is likely to be installed

close to equipment which may be sensitive to such a field, such

as microphone amplifiers or other high gain audio stages, be

sure you have adequate separation.

CONNECTIONS

AC Line

A 3-wire grounded power cord is provided on the  P50.5.  It

must  be connected to a properly grounded (earthed) AC

receptacle for your safety. Never break off the ground pin on the

plug  to avoid obtaining the proper adapter for 2-wire

receptacles. Do not use cords which are frayed, or whose plug is

damaged. Do not disconnect by pulling on the cord. Grasp the

plug itself.

High power output puts heavy demands on the supply wiring.

Each  P505  requires 15 amperes (at 120 VAC) for proper

operation.  A separate 20 ampere line is recommended. If

extension cables must be used, keep them short, and use  #14

gauge or heavier 3-wire cord.

Input

The amplifier is supplied with standard 2-circuit (tip-sleeve

or T-S) ‘phone’ jacks for normal unbalanced input connections.

These use single conductor shielded cable (shield connected to

the sleeve), or you may choose two wire shielded cable. With

two wire cables, and an unbalanced input, the signal, or ‘hot’

(black) lead connects to the plug tip and the ground (white or

red) lead connects to the sleeve. Hum is usually minimized in

two wire cable by connecting the shield to the ground wire at

one  end only.

¼’  PHONE PLUG

INSULATING        PLUG BODY

SLEEVE

SHIELDED

 

CABLE

SHIELD

 

MAY  BE CONNECTED

G R O U N D   LUG

 

(see

 

TEXT)

TO

If very long input signal cables are required, a balanced input

is usually advisable, using two wire shielded cable, and adding

the  Hafler BL500 option,   which  eliminates the need for

hum-sensitive  external input transformers. Then the 2-circuit

(T-S) phone jacks may be replaced by 3-circuit (tip-ring-sleeve

or T-R-S) jacks, wired with the ‘low’ (white or red) lead to the

ring,  and the shield to the sleeve. Or, 3-pin ‘Cannon XLR’

connectors may be installed via the chassis knockout provided.

The XLR connectors are often preferred for either balanced  or

unbalanced lines because of a locking provision. Because there

are  two wiring standards, you want to make sure all your

equipment  is consistent. The  IEC International standard

connects the shield to pin # 1 and the signal (‘high’ - black wire)

to pin #2.  On a balanced line, the return (‘low’  - white or red

wire)  would go to pin  #3.   The defacto American standard,

which is not as widely used, interchanges the connections to the

#2 and #3 pins.

Some  applications may require the use of an input

transformer,  to convert balanced lines to unbalanced

connections ahead of the power amplifier. Such transformers

are very sensitive to magnetic fields, such as those generated by

the  power transformer. You may have to install them a fair

distance from the  P505 to avoid hum pickup.

Output

The red and black binding posts were chosen for heavy duty

construction to handle the high currents which may be involved.

They are spaced for dual banana plugs, or you can connect bare

wire ends through the vertical holes in the shafts, which are

visible when the cap is unscrewed. To be certain that no wire

strands are unsecured, a tinned end, or a spade lug soldered to

the wire is recommended.

4

filters

Содержание P505

Страница 1: ...PERATION CAUTION IF THE SPEAKER FUSES BLOW SOME DISTORTED SOUND CAN BE HEARD THEREFORE IF AMPLIFIER MALFUNCTIONS ALWAYS CHECK FOR BLOWN FUSES FIRST LM135 THE DAVID HAFLER COMPANY 5910 Crescent Boulevard Pennsauken New Jersey 08109 Hafler P505 Professional Power Amp ...

Страница 2: ...ferred to 1 watt into 8 ohms A weighting Input Impedance 47 000 ohms in parallel with 50K ohms input level control Input Sensitivity 2 35 volts for 255 watts into 8 ohms 0 14 volt for 1 watt 2 volts for 400 watts into 4 ohms 0 08 volt for 1 watt Damping Factor 200 to 1 kHz into 8 ohms 60 to 10 kHz into 8 ohms Rise Time 10 kHz 80 volts p p square wave 10 to 90 2 5µs Slew Rate 1 kHz 120 volts p p sq...

Страница 3: ... and equipment service and provides a high level of protection to associated equipment and operating personnel P505 POWER AS A FUNCTION OF IMPEDANCE POWER PER CHANNEL BOTH CHANNELS DRIVEN The P505 incorporates a number of protective devices Separate power supply fuses for B and B on each channel individual thermal sensors on each heat sink a relay to disengage the output if excessive DC offset is ...

Страница 4: ...avier 3 wire cord Input The amplifier is supplied with standard 2 circuit tip sleeve or T S phone jacks for normal unbalanced input connections These use single conductor shielded cable shield connected to the sleeve or you may choose two wire shielded cable With two wire cables and an unbalanced input the signal or hot black lead connects to the plug tip and the ground white or red lead connects ...

Страница 5: ...r the rubber clad cables with woven shielding outperform vinyl coverings The vinyl insulation is usually supplied with a foil shield which can be easily tom so plugs must be wired with great care If permanent wiring involves fishing cables through conduits the vinyl cable is easier to use because it has less surface resistance but the foil shield is susceptible to splitting with undue stress Some ...

Страница 6: ...al having a specific porosity so exact replacement is best They may be ordered from the Hafler Company as part AF002 6 Back Panel Controls An input level control adjusts the sensitivity of each channel They are usually left at full clockwise rotation for maximum sensitivity and best signal to noise ratio Then 2 volts will drive each channel to full output 4 ohm load These controls have a B taper w...

Страница 7: ...50 or 60 Hz power lines The Export version includes an additional terminal strip to terminate the extra transformer leads In units supplied for 200 volt and higher AC lines the line fuse is a 7 ampere slo blo type and a different fan is installed along with different fan controlling power resistors which are mounted on the underside of the audio module The diagrams below show schematically and pic...

Страница 8: ...low impedance load where the fuse sizes may need to be increased If the amplifier requires factory service and the power transformer output appears normal when its secondary leads are disconnected from the diode bridge the transformer can be removed and the rest of the amplifier returned for service This greatly reduces the cost of shipping and the risk of damage in transit If you have isolated th...

Страница 9: ...iven in the event of excessive signal levels The output current is limited by the B and B fuses and the speaker fuses A protective relay circuit has a j section low pass filter which prevents signals above 10 H z from triggering the relay This circuit allows direct current to pass to IC101 which senses any offset above 3 5 volts and then opens the relay to protect the load RI06 and R107 form the r...

Страница 10: ......

Страница 11: ......

Страница 12: ...ch QBI I5 TAI I2 RPOI I RPOI I RF036 TAI I6 TAI I7 SZI 13 SLIII s402 S403 TR40 I TR402 TR40 I TS40 I TS402 DPDT slide switch DPDT slide switch Thermal breaker Thermal breaker Inrush limiter Thermal sensor Thermal sensor Fan I20 volt Fan 200 240 volt alternate SCHEMATIC DIAGRAM P505 PowerAmplifier r Copyright 1985 All rights reserved SZl22 SZl22 S F 0 2 4 S F 0 2 4 RZOl6 S F 0 2 5 S F 0 2 5 AAI I4 ...

Страница 13: ...anty 4 A description of the malfunction under occurred and whether it is intermittent what conditions it You are responsible for proper packing Insure it for the retail value United Parcel Service is suggested for domestic shipments and is the usual carrier for its return Units which required service under the warranty will normally be returned by UPS prepaid within continental USA Other return sh...

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