Do you have a question about the HR824 and is the answer not in the manual?
Questions and answers
Helmi
April 18, 2025
Hi there
Basically I am very happy with my HR 824s, I have 5 of them.
but after 15 years in Service one after the other starts hissing with white noise which eventually goes away after the speaker is on for at least an hour. Sometimes though it will not go away.
Any suggestions?
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C AU TIO N A V IS R IS K O F E L E C T R IC S H O C K D O N O T O P E N R IS Q U E D E C H O C E L E C T R IQ U E N E P A S O U V R IR C A U T IO N : T O R E D U C E T H E R IS K O F A T T E N T IO N : P O U R E V IT E R L E S...
INTRODUCTION This manual contains service information for the HR824 Powered Studio Monitor. It is recommended that you also have a copy of the owner’s manual as this contains the complete operating instructions. WARNING Service on the HR824 must only be undertaken by experienced service technicians.
The amplifiers’ gain and frequency THE PASSIVE RADIATOR responses are individually hand-trimmed by • The HR824 is a bass reflex 6th-order system, a host of infernal adjustment pots to rotating in geo-synchronous orbit. Rather compensate for typical manufacturing than use ports, the vent takes the form of tolerances.
(8 watts). INPUT SENSITIVITY CONTROL • In the ON position, the power amplifiers • The HR824 expects a line-level signal at its are live and operate normally. (The front input connectors. panel ON/OFF switch must also be ON.) •...
ON/OFF SWITCH necessary, to reduce the bass response. This • Use this switch to turn on or off the HR824 may allow the HR824s to play louder and from the front. It works with the POWER eliminate most amplifier clipping.
(310mm) –3 dB @ 47Hz –3 dB @ 80Hz High Freq Equalization: ± 2 dB @ 10kHz, shelving Mackie Designs is always striving to improve our products by incorporating new and improved materials, components and manufacturing Transducers Low-frequency driver: methods. Therefore, we reserve the right to change these specifications at any time without 8.75-inch (222mm) die-cast magnesium frame,...
PACKAGING CORNERS X 8 MANUAL 810-058-00 Note: Use only the exact packaging shown here. CARDBOARD COLLAR #1 Do not substitute any part 810-059-00 CARDBOARD or the speaker will be COLLAR #2 810-060-00 damaged. 1. Place speaker inside PACKING FOAM 790-019-00 the packing foam (VERY IMPORTANT) bag.
• Manually (and gently) check the woofer for any sticking or rubbing in its travel. NOTE: The four adjustment pots VR2, VR3, VR5 and VR6 are set and glued at the Mackie Factory for optimum performance and should not be touched. The factory settings are made when the speaker is all assembled and its output measured in an anechoic chamber with a calibrated microphone.
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TEST POINTS NOTE: INSTEAD OF USING J1, YOU CAN MEASURE THE BIAS ACROSS THE EMITTER ENDS OF R22 AND R24 AS SHOWN. +15V EMITTER EMITTER +49V -49V GROUND -56V +56V R166 -15V R170 EMITTER EMITTER NOTE: INSTEAD OF J6, YOU CAN MEASURE THE BIAS ACROSS THE EMITTER ENDS OF R166 AND R170 AS SHOWN.
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CONNECTING THE LOADS TWEETER LOAD RESISTOR J5 is your time portal vortex to another 8 ohm, 200 Watt realm of audio excitement. If you have a suitable connector, then wire the test loads as shown on the right. If you are not blessed with a spare View from the connector of this type, you can top, looking...
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LOW FREQUENCY AMPLIFIER TESTS ACOUSTIC SPACE SWITCH Disable the compressor circuit by shorting together pins 1 and 2 of J12. Turn off the amplifier and connect the two resistor loads as shown on the previous page. Set all switches to the NORMAL position and turn on the amplifier. Set your audio signal generator for an output of 300mVrms(-10.46dBV).
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LOW FREQUENCY AMP TESTS continued LOW FREQ SWITCH TEST Set your audio signal generator for an output of 300mVrms (-10.46dBV) Set the Acoustic Space switch to position A (Quarter Space). Measure the output into the 4 ohm load for the three positions of the LOW FREQ switch. Do these measurements fairly quickly because the amplifier will be warming up.
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HIGH FREQUENCY AMPLIFIER TESTS. NORMAL RESPONSE TEST Disable the compressor circuit by shorting together pins 1 and 2 of J12. Set your audio signal generator for an output of 300mVrms (-10.46dBV) Set the ACOUSTIC SPACE, LOW FREQ and HIGH FREQ switches to NORMAL. Do these measurements fairly quickly because the amplifier will be warming up.
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Carefully and gently check by hand that the woofer moves in and out without any rubbing or scraping of the voice coil. • Connect the woofer and tweeter to the HR824 amplifier. • Conduct a listening test and play some low frequency (30 to1kHz) test tones to verify the performance of the woofer driver.
• Always use the inner box, the outer box and the thin white foam when shipping the HR824 and use all other means of safe-shipping protection. This will protect the finish from getting scuffed up or the woofers from being damaged.
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PART NO. DESCRIPTION REFERENCE DESIGNATORS 224-004-00 CAP FILM SMT .0022 2.0% 224-006-00 CAP FILM SMT .0047 2.0% C11 C34 C38 C40 224-007-00 CAP FILM SMT .0068 2.0% C35 C53 224-009-00 CAP FILM SMT 2.0% C20-21 C25 C27 C29 C36 C51 224-010-00 CAP FILM SMT 2.0%...
Need help?
Do you have a question about the HR824 and is the answer not in the manual?
Questions and answers
Hi there Basically I am very happy with my HR 824s, I have 5 of them. but after 15 years in Service one after the other starts hissing with white noise which eventually goes away after the speaker is on for at least an hour. Sometimes though it will not go away. Any suggestions?