Haflee H O M E A U D I O C O M P O N E N T S Series 915 Preamp Series 0915 P R E A M P L I F I E R
NOTICE - IMPORTANT SAFETY INFORMATION RISK OF ELECTRIC SHOCK 00 NOT OPEN WARNING: TO PREVENT FIRE OR SHOCK HAZARD, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE. 1. A I 0 A The lightning flash with arrowhead symbol within an equilateral triangle is intended to alert the user to the presence of uninsulated “dangerous voltage” within the product’s enclosure, that may be of sufficient magnitude to constitute a risk of electric shock to persons.
11. NON-USE PERIODS During periods of extended non-use, the power cord should be unplugged from the power source. 12. CLEANING The equipment should be cleaned only as detailed in the operating instructions. 13. OBJECT AND LIQUID ENTRY Care should be taken so that objects and/or liquids, such as cleaning fluids or beverages, are not spilled into the enclosure of the equipment. 14. DAMAGE REQUIRING SERVICE Hafler equipment should be serviced by qualified service personnel when: A.
TABLE OF CONTENTS PERFORMANCE SPECIFICATIONS ............................................................................................ General Information ............................................................................................................... 4 5 INSTALLATION Rackmounting ........................................................................................................................ Ventilation/Placement ................................................................
PERFORMANCE SPECIFICATIONS All specifications are for 20 Hz - 20 kHz unless specified otherwise. PHONO SECTION (Measured At REC OUT) FREQUENCY RESPONSE: +/-0.1 dB MAXIMUM OUTPUT: 5 volts RMS TOTAL HARMONIC DISTORTION AND NOISE: Moving Magnet: .002% Moving Coil: .009% SENSITIVITY (For 0.5 volts RMS at REC OUT, @ 1 kHz): Moving Magnet: 6.0 mV RMS Moving Coil: 600 uV RMS SIGNAL TO NOISE RATIO (A-weighted, relative to 0.
GENERAL INFORMATION j INPUTS: Tuner, Video, CD, Phono/Aux 1, Aux 2, Tape Monitor OUTPUTS: Out 1, Out 2, Record Out, Headphone CONTROLS: input Selector, Volume, Tape Monitor , Tone Control In, Balance, Bass, Treble, Output Off, Power, Phono MM/MC INDICATORS: Mute/Standby, Power CONVENIENCE OUTLETS: 1 Unswitched, 4 Switched (Polarized) (Convenience Outlets are not included on 200-240 VAC units) PHYSICAL DIMENSIONS: 17” (W) x 7-5/8” (D) x l-3/4” (H) (excluding feet); Faceplate 17” or 19” (W). 43.
For units wired for 100-120 VAC, the Power Switch controls the Switched Convenience Outlets only. As soon as the 915 is plugged into the AC line, power is applied to the circuitry (regardless of the position of the front panel Power Switch). Therefore, all connections should be performed with the unit unplugged. For all units, when power is applied, the Ready Light will glow red for several seconds, indicating that the Audio and Headphone Outputs are muted.
INPUT SELECTOR BALANCE VOLUME CONTROL I -l I CONTROL TREBLE CONTROL BASS CONTROL HEADPHONE JACK POWER SWITCH UP TO TURN ON SWITCHED OUTLETS* 0 0 w . RACKMOUNT HOLES (19” VERSION ONLY) TAPE MONITOR SWITCH UP TO MONITOR TAPE INPUT TONE IN SWITCH UP TO ACTIVATE BASS & TREBLE OUTPUT OFF SWITCH UP TO TURN OFF OUT1 &OUT2 915 PREAMPLIFIER FRONT PANEL VIEW *lOO-120 VAC UNITS ONLY. 200-240 VAC UNITS ARE WITHOUT CONVENIENCE OUTLETS: POWER SWITCH CONTROLS PREAMPLIFIER POWER.
UNSWITCHED LINE VOLTAGE RATING LINE CORD CONNECTOR AC SWITCHED OUTLETS OUT 1 TAPE AUX 2 TUNER INPUTS VIDEO TOP ROW - RIGHT CHANNEL BOTTOM ROW - LEFT CHANNEL OUTPUTS REC OUT OUT 2 CD 200-240 VAC UNITS ARE WITHOUT CONVENIENCE OUTLETS. *100-l 20 VAC UNITS ONLY.
TAPE INPUT/ RECORD OUTPUT The 915 incorporates one monitoring loop for use with tape decks, or other input/output signal processors. The Ret Out jack feeds a signal to a tape recorder’s input. The signal present at this output is the same as indicated by the Selector Switch. This output may alternately be used to feed the input of a signal processing device, such as an equalizer.
OUT 1, OUT 2 AND OUTPUT OFF SWITCH Activating this switch (UP position) turns off both Out 1 and Out 2. It does not affect the headphone output. This control is useful for turning off the signal to the power amplifier(s) during headphone listening, or for general system muting purposes. When activated, the output switch disconnects the line amplifier from the output jacks, and grounds the jacks to prevent possible system noise due to open amplifier inputs.
JFET BUFFER AND RECORD OUTPUT DRIVER The output of the Selector System is followed by a very high input-impedance JFET buffer pair to establish negligible CMOS switch loading (for low distortion) and to provide a low-impedance source for the Record Output and the Volume and Balance controls. TAPE MONITOR SWITCHING The Tape Monitor Switch drives a relay to break the line input path to insert tape input signals.
Internal signal grounding has been carefully routed to follow the signal path from the input jacks, through the Selector System, through the Volume and Balance Controls, and finally to the line amplifier. All power supply ground paths are returned to a single “star” ground point at the power supply to minimize ground modulations. Extensive use of ground planes and interchannel shields maximize inter-channel separation.
MAIN PC BOARD PHONO PC BOARD -T INSTALLATION OF OPTIONAL PHONO PRINTED CIRCUIT BOARD PLASTIC STANDOFFS 4 PIN CONNECTORS PLASTIC BUTTON
INSTALLING CARTRIDGE LOADS Optional cartridge loading is a “fine tuning” matter. Many cartridges are not sensitive to loading and work well without it. Only a cartridge’s manufacturer can provide recommended loading, as every cartridge is different. And only the user can say for sure whether or not it produces meaningful sonic improvement. Components suitable for cartridge loads may be obtained from electronic parts or specialty audio Capacitors component suppliers.
1 3181' MAX.
Place the preamplifier on a soft, protective surface. Remove the eight allen head screws (four on each side), and six phillips head screws (three each on top and bottom), securing the top and bottom covers. Remove covers. 2) Referring to the diagram “Main Printed Circuit Board Component Layout”, locate the three wire jumper locations labelled “A”, “B”, and "C", in front of the power transformer. These jumpers control the series/parallel connections of the power transformer’s primary.
GROUND LOOPS Ground loops are characterized by a low level hum or buzz in the system. Loops are caused by a voltage potential difference between two points in a ground circuit, and aggravated when multiple paths for a given circuit exist. Noise-free audio performance is dependent upon all grounds being at the same potential, with a single path for each ground connection. Ground loops can exist in two forms: 1) loops created in audio interconnects, and 2) loops created between earth grounded chassis.
I t I ONE CHANNEL SHOWN, PHONO OPTION INSTALLED 915 PREAMPLIFIER FUNCTIONAL BLOCK DIAGRAM
PARTS LIST - MAIN CIRCUIT BOARD DESIGNATORS l-99: FOR COMMON AND RIGHT CHANNEL PARTS 100-199: FOR LEFT CHANNEL DESIGNATOR PART NUMBER VALUE ALL RESISTORS 1/4 WATT, 1% METAL FILM R1, R101 2.15K R2, R102 20K R3 100K R4 100K R5 100K R6, R106 20K R7, R107 1K R8, R106 1K R9, R109 33.2 R10, R110 33.2 R11, R111 20K R12 221 R13, R113 20K 100K R14 R15, R115 182K 100K R16, R116 R17, R117 150 274K R16, R116 R19 10K 162K R20 100K R21 100K R22 4.75K R23 47.5K R24 1.5K R25 2.
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A&B=100-12OVW: c - 2 0 0 - 2 4 0 VAE: rJoba’----- -1 i +--A-----L’ D7 1 N5226B Bci D6 lN4145 PWNOOPllONJUMPERS PHONOPWER K 1 4 hL RlQ 1OK 1 .
Rlb 274K JlO R17 MUTE RUAY BOARD CIRCUIT SCHEMATIC ENANCE UNLESS SPECIFIED OTHERWISE 1. RIGHT CHANNEL ONLY SHOWN 2. COMPONENT DESIGNATORS RIGHT CHANNEL 1-99 FOR COMMON AND PARTS. 100-199 FUR LEFT CHANNEL 5. ML RESISTORS IN OHMS, CAPACITORS IN M C I ROFARADS 4.TCNE5WllCHSHWNINBYPASSPO5RlCN 5. TAPE MONITOR SWITCH SHOWN IN WE POSITION 6.MUERW.
PARTS PARTS LIST LIST - PHONO BOARD DESIGNATORS 1- 99: FOR RIGHT CHANNEL PARTS 100-l 99: FOR LEFT CHANNEL DESIGNATOR VALUE PART NUMBER All Resistors 1/4 Watt, 1% Metal Film R1, R101 R2, R102 R3, R103 R4, R104 R5, R105 R6, R106 R7, R107 R8, R108 R9, R109 R10, R110 R11, R111 R12, R112 R13, R113 R14. R114 R15, R115 R16, R116 R17, R117 R18, R118 R19, R119 R20, R120 681 33.2 L o w Noise 33.2 L o w Noise 681 26.7K 332K 47.5K 316 100 33.2 L o w Noise 3.32M 1 .OK 22.1M 10M 316 3.32M 1 .OK 22.
l-l I I I 1 R3n RlO 4-k R 2 -c=l- a "R1B05 4 -fxb R 1 0 3 0 RllO < 3 R102 > D En 0104 c5 R;' %13 jRSo f;oRll Rl9 1 R6 R l 1 8 "OS ii:: R l 1 3 Rfli Rl150 Rll9 Rl4 J3 R108 BfWOd' Rl14 52 4 [I 4 PHONO BOARD COMPONENT LAYOUT DIAGRAM -23-
PHONO INPUT R15 316 L CH I IMC/MM SWrrCH a2 f D,‘) I.,#. Rl RR1 -. 1Mp + = 1 .OK I 05 2sJ74 J2 RlO PHONO OUTPUT II I, B R18 , 22.1M 06 2SK163 -%+ Q R20 316 PHONO POWER 1. RIGHT CHANNEL ONLY SHOWN. 2. COMPONENT DESIGNATORS 1-99 FOR RIGHT CHANNEL PARTS. 1 W-199 FOR LEFT CHANNEL. 3. ALL RESISTORS IN OHMS, CAPACITORS IN MICROFARADS. 4. MC/MM SWITCH SHOWN IN MOVING MAGNET POSITION.
SERVICE POLICY AND LIMITED WARRANTY If you encounter any difficulty or have any question concerning your 915 Preamplifier, please call our Customer Service Department weekdays, 8 am to 3:30 pm, Mountain Standard Time, at 602967-3565. Should you have any doubts as to whether the preamplifier is malfunctioning and requires service, please call us before sending in for repair. All units being returned (regardless of warranty status) must receive a Return Authorization (RA) number.
