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M2600
FR Series Power Amplifier
SERVICE MANUAL
1998, 1999 MACKIE DESIGNS, INC.
820-180-00
Page 3 is interactive
SERVICE ON THIS EQUIPMENT IS TO BE PERFORMED BY
EXPERIENCED REPAIR TECHNICIANS ONLY
2
Click on any item to open that page
CONTENTS
INTRODUCTION ................................................................................. 3
Technical Support ........................................................................ 3
Disclaimer ....................................................................................... 3
BLOCK DIAGRAM ............................................................................. 4
SPECIFICATIONS ................................................................................ 5
TROUBLESHOOTING TIPS ............................................................... 6-7
RELIABILITY VERIFICATION ........................................................... 8-9
CIRCUIT THEORY ........................................................................ 10-13
ASSEMBLY DRAWINGS .............................................................. 14-19
PARTS LIST ................................................................................... 20-30
FOLD-OUT SECTIONS: schematics and pcb layouts
Channel 1 .............................................................................. 129-1
Channel 2 .............................................................................. 130-1
Input board........................................................................... 131-1
Display board ........................................................................ 132-1
Power Distribution and in-rush limit ..................................... 133-1
Voltage Amp and protection ............................................ 170-1
Power Supply ........................................................................ 171-1
Output board ....................................................................... 172-1
15 V supply/Fan drive board ............................................. 186-1
INTRODUCTION
ALL BOARDS
SERVICE ON THIS EQUIPMENT IS TO BE PERFORMED BY
EXPERIENCED REPAIR TECHNICIANS ONLY
This manual contains basic service information. It is essential that you have a
copy of the user’s manual as this contains the complete operating instructions.
SERVICE TECHNICAL ASSISTANCE
Mackie Designs, Service Technical Assistance, is available 8AM - 5PM PST, Monday through
Friday for Authorized Mackie Service Centers, at 1-800-258-6883. Feel free to call with any
questions and speak with a carefully-calibrated technician. If one is not available, leave
a detailed message and a qualified Mackoid will return your call asap.
DISCLAIMER
The information contained in this manual is proprietary to Mackie Designs, Inc. The entire
manual is protected under copyright and may not be reproduced by any means without
express written permission from Mackie Designs, Inc.
3
4
MACKIE DESIGNS
M•2600
BLOCK DIAGRAM
9/21/1998
THRU OUTPUT
(XLR-MALE)
LINE INPUT
(XLR-FEMALE)
LINE INPUT
(1/4" TRS)
THRU OUTPUT
(XLR-MALE)
LINE INPUT
(XLR-FEMALE)
LINE INPUT
(1/4" TRS)
FUSE
LOW CUT
FILTER
FREQ
LOW CUT
FILTER
FREQ
LAMP
POWER
SWITCH
TRANSFORMER
THERMAL
IN-RUSH
LIMIT
HIGH
LOW
60-90-120Hz
CROSSOVER
THRU–LOW–HIGH
CH 2
SIG
HIGH
LOW
60-90-120Hz
CROSSOVER
THRU–LOW–HIGH
CH 1
SIG
CH–2
TOROIDAL POWER
TRANSFORMER
IN-RUSH CONTROL
LIMIT–OFF-LOW OUT
Σ
STEREO-MONO-BRIDGED
22 VAC
-15 VDC
+15 VDC
+
30 VDC
–
+
CH.1 100 VDC
–
+
CH.2 100 VDC
–
STEREO-MONO-BRIDGED
STEREO-MONO-BRIDGED
(THE CHANNELS ARE
SUMMED IN MONO
OR BRIDGED MODE)
LIMITER
CONTROL
CH–1
LIMIT–OFF-LOW OUT
LIMIT–OFF-LOW OUT
CH 2
TEMP
SENSOR
CH 1
TEMP
SENSOR
+
CH.1 115 VDC
–
CH.1 DISSIPATION
CH.2 DISSIPATION
+115VDC
–115VDC
–100VDC
+15VDC
+15VDC
+100VDC
MUTE
DC OFFSET
PROTECT
SHORT
MUTE
CHANNEL 1
POWER
AMPLIFIER
PROTECTION CIRCUITRY
FUSE
FUSE
MUTE
DC OFFSET
PROTECT
SHORT
MUTE
CHANNEL 2
POWER
AMPLIFIER
CH 2
SIG
CH 1
SIG
SHORT 2
0
FAN IDLE/VARIABLE CH.1 POWER DETECTOR
FAN IDLE/VARIABLE CH.2 POWER DETECTOR
0
45 C – 65 C SPEED CONTROL CH.1
0
0
45 C – 65 C SPEED CONTROL CH.2
OL
–3
–6
–9
–20
SIG
COLD LED
HOT LED
CH.2 DISSIPATION
PROTECT
SHORT
OL
–3
–6
–9
–20
SIG
CH.1 DISSIPATION
METER
DRIVE
SHORT 1
PROTECT
SHORT
METER
DRIVE
VARIABLE SPEED FAN CONTROLLER
OVER TEMPERATURE
DETECTOR
IN-RUSH CONTROL
LOW VOLTAGE DETECT
TRANSIENT SOA FLT
STEADY STATE SOA FLT
OUTPUT DISSIPATION
OUTPUT STAGE CURRENT
OUTPUT STAGE VOLTAGE
PROTECTION CIRCUITRY
FUSE
FUSE
IN-RUSH CONTROL
LOW VOLTAGE DETECT
TRANSIENT SOA FLT
STEADY STATE SOA FLT
OUTPUT DISSIPATION
OUTPUT STAGE CURRENT
OUTPUT STAGE VOLTAGE
+30VDC
-30VDC
22VAC
LIMITER
+
CH.2 115 VDC
–
–115VDC
–100VDC
+15VDC
+15VDC
22VAC
LIMITER
TRANSFORMER
THERMAL SWITCH
SHORT 1
SHORT 2
(THE SHORT LEDS ARE
JOINED IN BRIDGED MODE)
CH.2 GAIN
INVERTER
(FOR BRIDGED MONO
OPERATION)
CH.1 GAIN
+115VDC
+100VDC
0
1-
1+
1-
1+
1-
1+
+
-
+
-
FAN
CH.2 MUTE 800C MUTE
0
52 C UN-MUTE
800 C MUTE
CH.1 MUTE 52 C UN-MUTE
OUTPUT
RELAY
OUTPUT
RELAY
CH. 2
SPEAKER
OUT
CH. 2
SPEAKON
BRIDGED
MONO
SPEAKON
CH. 1
SPEAKON
CH. 1
SPEAKER
OUT
Block diagram
Specifications
Maximum Power at 1% THD, midband:
500 watts per channel into 8Ω
850watts per channel into 4Ω
1300 watts per channel into 2Ω
1700 watts into 8Ω bridged
2600 watts into 4Ω bridged
Continuous Sine Wave Average Output Power,
both channels driven:
425 watts per channel into 8Ω from 20Hz to 20kHz,
with no more than 0.025% THD
700 watts per channel into 4Ω from 20Hz to 20kHz,
with no more than 0.05% THD
1000 watts per channel into 2Ω from 20Hz to 20kHz,
with no more than 0.1% THD
1,400 watts into 8Ω from 20Hz to 20kHz, with no more
than 0.05% THD
2000 watts into 4Ω from 20Hz to 20kHz, with no more
than 0.1% THD
Note: Power ratings are specified at 120VAC line voltages.
The M2600 power amplifier draws large amounts of
current from the AC line with continuous sine wave testing. Accurate measurement of power requires a steady
and stable AC supply. This means the line impedance
must be very low to insure that the peak AC line voltage
does not sag to less than 97% of its value.
If driving highly reactive loads, we recommend that the
limiter circuit be engaged.
Power Bandwidth:
20Hz to 70kHz (+0, -3 dB) @ 700W into 4 Ω
Frequency Response:
20Hz to 40kHz (+0, -1 dB)
10Hz to 70kHz (+0, -3 dB)
Slew Rate:
Voltage Slew Rate > 60V/µs
Current Slew Rate> 30A/µs at 2Ω
CMRR:
> 40 dB, 20Hz to 20kHz
Load Angle:
8(±jx) time independent at 8Ω
4(±jx) time dependent, T > 6 min. at 4Ω
2(1±jx) time dependent, T > 2 min. at 2Ω
Transient Recovery:
High Frequency Overload and Latching:
No latch up at any frequency or level.
High Frequency Stability:
Unconditionally stable, driving any reactive or
capacitive load.
Turn On Delay:
3-5 seconds
Variable Low-Cut Filter:
10Hz (Off) to 170Hz, 2nd-Order Bessel
Internal Crossover:
Switched: 60Hz/90Hz/120Hz, 4th-Order Linkwitz-Riley
Lowpass outputs switchable to internal Subwoofer
mode.
Lowpass and Highpass outputs switchable to Thru
output jacks.
Limiter Section:
Complementary Positive and Negative Peak Detecting
Distortion:
< 0.025% @ 8Ω
< 0.050% @ 4Ω
< 0.150% @ 2Ω
Signal-to-Noise Ratio:
> 107 dB below rated power into 4Ω
Channel Separation:
> 80 dB @ 1kHz
Damping Factor:
> 350 @ 400Hz
Input Impedance:
24kΩ balanced
Input Sensitivity:
1.23 volts (+4 dBu) for rated power into 4 ohms
Gain:
< 5µs
< 1µs for 20 dB overdrive @ 1kHz
Bridged mono operation:
SMPTE IMD, TIM
Rise Time:
Indicators:
6 meter LEDs per channel
SIG (Signal Present), -20, -9, -6, -3, OL (Overload)
CH 1 & 2
PROTECT LEDs
SHORT LEDs
TEMP STATUS
COLD/HOT LEDs
Physical:
(three rack spaces high, standard rack width)
Height
5.20 inches
(132mm)
Front panel Width 19.00 inches
(483mm)
Chassis Width
17.24 inches
(438mm)
Depth
15.65 inches
(398mm)
Overall Depth
16.67 inches
(423mm)
Handle Depth
1.64 inches
(42mm)
Weight
55 pounds
(25 kg)
32.7 dB (43V/V)
Maximum Input Level:
9.75 volts (+22 dBu)
5
Troubleshooting Tips-output failures
After a catastrophic failure, it is likely that some of the supply fuses will be blown. Check and
replace any fuses on the 129, 130, 133, and 171 boards. Short across the Left most lead of R1 to
the right most lead of R2 on the 133 board to short out the two 15W inrush resistors (see the
diagram on the next page). Very slowly bring up the Variac while monitoring line consumption.
It is likely that substantial line current will be pulled due to shorted output parts. If excessive
current is not pulled, but a channel still stays in “protect” mode, the unit will still need repair.
Remove the main heatsink sub-assembly from the unit and check for shorted output
transistors. Once it has been determined which channel failed, remove it’s respective V-amp/
Protection board (055-170-00) to make access to the channel board easier. If one bad output is
found, replace all 16 in the channel. When an output device shorts it can place high current
stresses on the other output parts. These output parts can fail over time. Since long term
reliability is paramount, please replace all the outputs.
All 16 of the 3W 0.33Ω emitter resistors must be verified for proper value. Any off-tolerance, or
open parts, need to be replaced. An off tolerance (higher resistance) emitter resistor will prevent
it’s related output transistor from “doing it’s share” and will place more stress on it’s mates in the
output section. Also verify the 16 base drive resistors (2.2Ω, 1/4W, fusible) are all OK. Verify that all
eight drivers and that the pre-drivers are not shorted. If one driver is shorted replace it’s mates.
Do the same with the pre-drivers. Also check all the resistors surrounding the drivers and predrivers. Measure the resistance between the “+I-sense” and “-I-sense” lines. The resistance should
be 82.5Ω +/-5%. If this resistance is higher, check for open 33Ω fusible resistors on these lines. Take
your time here looking to find all damaged parts: If one part is missed it still takes the same huge
amount of time to disassemble the main heatsink assembly. After replacing the outputs, drivers,
and pre-driver verify that the silicon transistor insulator wasn’t damaged (No shorts between
collector legs and the heatsink).
On the 170 board, check the VI limiters and detectors. It is not uncommon to damage these
parts when the amplifier fails in a spectacular way! Look for shorts on Q24, Q25 or open R151 or
R146. It is critical that these sections are working correctly. Shorted transistors can cause some
odd asymmetrical clipping problems. Open parts will not allow the current limiting to operate
effectively. If problems exist in these sections the amplifier might fail into a short, or might clip
prematurely when loaded to 2 Ω.
All of the above trouble shooting (not including part replacement) takes perhaps 30 to 45
minutes to do. If you take the time, and do all that is indicated above, it will allow 99% of the
amplifiers to come up the first time! Trying to hurry, and skipping what is suggested, can lead to
a frustrating and time consuming repair.
Reassemble the main heatsink sub-assembly and plug the two power supply cables back
into the 171 board (This can be done without installing the assembly back into the unit). Slowly
bring up the supply and verify that line consumption isn’t excessive and that the output is
centered (no DC offset). This can be measured on the “AMP-OUT” testpoint on the 170 board. It
might be desirable to defeat the amplifier muting temporarily (Short “MUTE-VA” to “-15V-AMP”
testpoints on the 170 board) so the channel is active even when the supplies are still very low. If
the amp stays centered, power down the assembly and discharge the two main +/-100V
supplies on both channels. Remove any temporary jumpers and reinstall the assembly into the
chassis. Power the unit and verify that the repaired channel will pass a nice clean rail to rail sine
wave. Next proceed to the “Reliability Verification” section on page 8.
WARNING: FUSIBLE RESISTORS MUST ONLY BE REPLACED BY THE EXACT REPLACEMENT PARTS.
ALWAYS CHECK THE PARTS LISTS TO VERIFY WHICH RESISTORS ARE THE FUSIBLE TYPE
BEFORE REPLACING ANY RESISTORS IN THIS AMPLIFIER.
6
Various test points
170 board (Bias and check points)
R146 Q24
Q25
R151
MUTE-VA
J18
SOA
POWER
J19
-15V-AMP
SOA
TRANSIENT
AMP
BIAS OUT
TEST
BIAS
ADJUST
ADD A TEMPORARY SHORT
(SEE TROUBLEHOOTING TIPS)
133 board (inrush bypassing)
186 board (fan speed adjustment)
J1
J3
J2
R1
129 channel board
BR= BASE RESISTOR (2.2 OHM, 1/4W FUSIBLE)
ER= EMITTER RESISTOR (0.33 OHM, 3W)
ER
BR
ER
BR
ER
BR
ER
BR
ER
BR
+I SENSE
ER
BR
ER ER
BR
ER
BR
ER
BR
ER
BR
ER
BR
ER
BR
ER
BR
ER
BR
ER
BR
-I SENSE
J6
+I SENSE
7
Reliability Verification Procedure
After the unit has been repaired, the following should be done to assure long term reliable
operation. If a distortion analyzer is present, distortion specifications should be verified. See the
previous page for the 170 and 186 boards with some test points noted.
1. Adjust the bias control (R163 on 170 Board) in both channels for 12mV +/- 1mV measured
at the bias test points (J23 along 170 board back edge) after unit has idled for a few
minutes. This is with no signal and no load. The Pot and test points are clearly marked on
both the top and bottom sides of the 170 board.
With Full AC line voltage applied to unit, it will pull around 130W from the line (1.6A at
120V). Measure for DC offset on both output connectors, it should be less than +/- 50mV.
2. Verify and adjust the fan speed if needed. On the 186 board, short pin 1 to pin 2 on J3.
Adjust R1 for 28V (+0V -1V) across J1 and J2. Remove the shorting jumper on J3. All the
test points and pots are clearly labeled on the back side of the PCB and are easily
accessed with the main heatsink sub-assembly installed.
3. Apply a 1KHz sine wave to the inputs and verify that the unloaded outputs have a
waveform that is symmetrical and undistorted. Drive the outputs into clipping and
carefully verify symmetrical “flat-topping” on the waveform.
4. Reduce the output levels, install a 0.1µF capacitor jumper from the output to ground
connections, and verify that clipping behavior is proper. Verify that no high frequency
oscillation occurs near and at clipping (parasitic oscillation).
5. Remove capacitive loading and minimize sine output. Verify and re-adjust the bias if
required. Note that the bias will not drift appreciably in a unit that is functioning properly.
6. Connect the amplifier directly to the AC line and connect an 8Ω dummy load to both
channels. Each 8Ω dummy load should have a minimum power rating of 500W. Bring the
sine wave level up on both channels and verify symmetrical clipping. The output will clip
somewhere between 150V - 180V pk/pk depending on how stiff the line is. Clipping
should be as described above. Add the 0.1µF capacitive loading and verify clipping is still
well behaved.
7. Individually load Channel 1 and Channel 2 with 2Ω . Each 2Ω dummy load should have
minimum power rating of 1500W. Clipping should be symmetrical, well behaved , and
occur somewhere around 120V - 140V pk/pk. Verify that clipping is well behaved after
adding the 0.1µF capacitive loading. Reduce the output level to zero and remove the
loading.
8. Next verify the two different short detectors. Perform these tests first on channel-1 and
then repeat for channel-2. On the 170 board, short J18 pins 1 and 2 (this defeats the
average power SOA detector and allows the transient SOA detector to be tested).
Adjust the output level to 60V pk/pk and short the channel-1 output line. Channel-1’s
front panel “short” and “protect” LEDs should turn on and the respective channel will
mute for about 5 seconds. On the 170 board, remove the short on J18 and install a short
on J19 pins 1 and 2 (this defeats the transient SOA detector and allows the average
power SOA detector to be tested). Adjust the output level to 60V pk/pk and short the
channel output line. Channel-1’s front panel “short” and “protect” LEDs should turn on
and the respective channel will mute for about 5 seconds. Remove the shorting jumpers
on channel-1 and repeat above testing on channel-2.
8
9. Place the amplifier in bridge mode and connect 4Ω loading to the bridge outputs
(across both “+” output binding posts). The 4Ω dummy load should have a minimum
power rating of 2000W. Slip some card stock between the heatsink-outlets and chassis
sides to temporarily restrict the airflow. Monitor one of the outputs and adjust for a 60V
pk/pk signal. Short across both outputs and verify that all four ‘Short” and “Protect” LEDs
light and the amplifier mutes for 5 seconds.
10. Remove the short, monitor one of the outputs, and adjust for a 90V pk/pk sine output
(1000W of output power bridged). After a few minutes the fan will begin running faster
and faster (heatsink between 45°C and 65°C) and a short time later the amplifier will
mute (heatsink at 80°C). The “Hot” and “protect” LEDs will come on. Remove the card
stock and after a few minutes the amplifier will come out of mute mode and the “cold”
LED will return.
11. Disconnect the loading and remove the input signals. Reconnect the amplifier to a
Variac and confirm that the idle consumption is roughly 130W or 1.6A, as before.
Connect the amplifier to speakers and verify that it sounds OK with music.
12. Perform the following leakage test before returning the amplifier to your customer:
1. Connect the amplifier under test to an AC power source using a ground-lift
adaptor, leaving the amplifier’s safety ground floating. Turn the amplifier on.
2. Make a small loading RC circuit as shown in the diagram below, and connect
the AC volt meter between the AC power source ground and any exposed metal
on the unit under test.
3. The meter reading should be less than 750mV AC (note: this is equivalent to
0.5mA of leakage current).
4. Flip the plug over in the receptical so the hot and neutral are swapped.
Verify that the reading is still less then 750 mV AC.
9
Circuit Theory
Much of the circuitry in the M•2600 we hope is self explanatory from the schematics. This
section will explain the unique circuits and architecture. Examples in this section will refer to
Channel 1 for circuitry that is identical on both channels.
INPUT CIRCUITRY
The signal path begins with the INPUT BOARD (055-131-00). Following Channel 1’s input, signal
is fed to a unity gain differential op-amp, U1A. The signal is next sent to U1B which serves as a
12dB/Oct. highpass filter. If not in SUBWOOFER mode, and if running in STEREO mode, the
summing amp (U3B) and 24dB/Oct. Likwitz-Riley Crossover (U3A, U2, U4) are bypassed. The signal
is sent via J11 to the gain control on the DISPLAY BOARD (055-132-00). After the gain control, the
signal is buffered by U1A, returned to the INPUT BOARD and routed to the Channel-1 amplifier
board via J6.
Channel 2’s input signal path is electrically identical to Channel 1’s in STEREO mode.
In PARALLEL MONO mode, Channel-1’s and Channel 2’s input signal is summed via U3B and is
sent to both channel’s front panel level controls via SW3A and SW3B.
For BRIDGE MONO operation, these summed inputs are sent to the channel-1 front panel
level control which in turn feeds the channel-1 amplifier and also the inverter U10A. The output of
U10A is routed to the channel-2 amplifier via SW3C. Also in BRIDGE mode, SW3D connects both
channel-1’s and channel-2’s protection circuits together. The result being that when one
amplifier detects a short circuit condition it will mute and immediately tell channel-2 to mute.
Muting lasts around 5 seconds and the amplifier un-mutes until the next shorted condition is
detected.
The limiters (U6, U5, U7 and their associated components) are always in the signal path. When
the limiter is switched off (via SW4) the LDR (Light Dependant Resistor) is in parallel with the
source resistor (R39) and will not reduce signal amplitude. When the limiter is switched on, the
LDR (U5B) is switched as a shunting element to ground. The Baker clamp in the power amplifier
detects clipping and the LDR shunts away driving voltage until clipping almost disappears. This
type of limiter is know as a feedback style (As opposed to feedforward style) of limiter.
U6 is also used for the amplifier input slew clamps, comprised of local +/-5V supplies (D7, D8
and associated) and clamping diodes (D13 and D14). These diodes clamp the voltage feeding
the power amp to around 10V pk/pk or about 6dB above the amplifier’s clipping point. This
ultimately limits the risetime of the signal presented to the power amplifier, controlling commonmode conduction in the power amplifier output stage.
Output from each crossover can be routed to the rear panel THRU jacks via SW2 and SW6. In
the THRU position the THRU jack is hardwired to the input jacks. In LOW and HIGH output modes,
the lowpass and highpass outputs of the crossover respectively are fed to the THRU jack. In these
modes the output is impedance balanced via R28, R29 and R23.
POWER AMPLIFIER CIRCUITRY
The M•2600 use a class AB triple darlington output stage with complementary output
devices. The output stage and the bias trackers are on the channel boards (129 and 130 boards)
while the voltage amplifier and amplifier protection circuits are housed on two identical v-amp
/ protection (055-170-00) boards. Each channel has local main +/- 100V power supplies, and a +/
- 115V stacked supply for the front end circuitry. Each amplifier also has floating +/-16V supplies
10
that float along with the amplifier output line (D3 & D4 and associated parts on the 129 board).
Common +/-15V supplies are shared throughout the product.
Referring now to the 170 schematic: The amplifier is muted for 3 seconds on power up as C29
charges via R56. When this voltage has charged above 11.6V, U3C goes low turning on Q7,
providing current for the differential pairs. The output of U3C, labeled “MUTE-VA”, when low turns
on the Voltage Amplifier. Two seconds after MUTE-VA goes low, mute “MUTE-OP” goes low (Q27)
closing the OutPut relay passing signal along to the output terminals. (Wait a minute! Differential
Pairs? Read on…)
An immediately obvious departure from standard designs is the Differentials and Symmetrical
Voltage Amps. The reasoning behind this front end architecture is actually quite simple.
Transistor transfer characteristics are not entirely linear, so even the best conventional front end
design will introduce some distortion. Most amplifiers use negative feedback to reduce this
problem (creating a few more in the process). Mackie FR Series amplifiers take a different
approach. By using two complementary “mirror image” front end circuits, any distortion caused
by non-linear transistor curves is effectively canceled out in the bias string, without feedback!
Another design feature unique to Mackie FR Series Amplifiers is the Baker Clamp. The Baker
Clamp has two functions; 1) Prevent output transistors saturating, 2) Drive the LIMITER LDR.
Referring to the again to the 170 schematic: Q20 is a common base amplifier, it will turn on if
Q2’s collector rises more than three diode drops above the +100V supply, preventing Q2’s
collector from rising further. There are three diode drops between Q2’s collector and the base of
pre-driver transistor (Q26 on 129 board). Once the output from the collector of Q2 makes it to
the emitter of the output devices, there will be a total of six diode drops in series. Three “drops”
up and six down: As a result, the output transistor emitters will never see a voltage greater than
three diode drop below the +100V supply (even if the +100V supply fluctuates) and will never
saturate. This will consequently remove saturation of the output stage, as a source common
mode conduction. When the amplifier clips, Q20 and Q15 also send out “clipping pulses” at
their collectors that is coincident with baker clamp conduction. These clipping pulses are crosscoupled to Q21 and Q22 and are stored in C47 and C51. These stored pulses allow for quick
attack and slow release required by a peak limiter. Output from Q21 and Q22 is coupled to the
LDR LED section via R110 and R152.
PROTECTION CIRCUITS
The M•2600 has several protection circuits in addition to main rail fuses on each channel.
Circuits mute the amp if the output devices are loaded beyond their safe operating area (SOA).
If there is DC on the output line, output relays open, disconnecting the load. The amplifier will
also mute if the power transformer or main heatsink get too hot, if the input AC line voltage is
low, or if either of the +/-15V supplies fails.
Turn-On Inrush Current Limiter
For the first second of operation there are two 15W power resistors (located on the 133
board) in series with the power transformer which eliminates what would otherwise be an
extremely high turn-on current. After 1 second these resistors are shunted with a relay. This relay is
turned on when the collector of Q26 (170 board) goes high. Note that either or both Q26’s on
the two 170 boards can turn on this relay.
11
SOA protection
There are two SOA detectors in the M-2600: One that monitors steady state output stage
dissipation and one that monitors transient high current events. Both detectors need to monitor
the output stage current.
A voltage, representing output stage current, is derived by first sampling the voltage drop
across the output transistor emitter resistors. These voltages are rectified via U9A R87, R88, R59
and R89. The rectified voltage is converted to a current via U9B, Q23, and associated. This current
is referenced to the output line and must first be re-referenced to the +115V supply via Q14, D47
and associated. The current available at the connector of Q14 is converted to a voltage that is
ground referenced via R138 and R162. This is buffered via U8A and adjusted via R162 such that
1 amp of output stage current is equal to 100mV of detected output.
This current is compared to what represents a safe operating current at U4A (part of the
transient SOA-Fault detector). If the current is greater than allowed for more than 10mS (Timing
determined by R77 and C36), U4B sends out a fault indication which mutes the amplifier via U3C
and associated, and fires the short led for 5.5 seconds (U3B and associated).
While the output stage is quite tolerant of very high current demands for a very short time, it
would destroy itself if it had to provide these currents on a long-term basis. The second detector
actually looks at long-term dissipation in the output stage, and if excessive, will mute the
amplifier. We already have a signal that is proportional to output stage current as described
above. This signal is fed to one input of analog multiplier U7 via R80 and R84.
U6A and U6B and their associated components look at the -100V supply and the amplifier
output line. These voltages are converted to currents via R101, R129 and R130 and are rectified
and summed such that for every volt between the output line and the supply rail, 100mV is
presented as output. This second signal is presented to the other input of multiplier U7 via R133
and R82. Output from U7 is in the form of a current and is converted to a voltage via R136 and
U8B. The gain of this multiplier is such that for 200 watts of output stage dissipation, 1 volt of
output is obtained. The output of U8B is instantaneous power and is long-term averaged via
R135 and C40. The cutoff of the filter is quite low in frequency, such that even a 20Hz signal on
the amplifier output results in very little ripple voltage at C40. If the voltage on C40 is greater
than 5V (equivalent to 1000W of output stage dissipation), U4C will toggle, muting the amplifier
and firing the SHORT LED as above. Approximately 200mS of dissipation above 1000W is required
to cause a fault.
DC Fault Detection
The amplifier output drives the subsonic lowpass filter of the DC fault detector (R154, C65
and C64). If the amplifier were to fail and short to the +100V rail, C64/C65 will charge to more
that 5V in a few hundred milliseconds. Local +/-5.1V references on U2C and U2D set the threshold
where: when the amplifier output voltage is “stuck” to greater than +/-5.1V, either comparator
output will go low. This will open Q27, and in turn open the speaker relay on the respective
channel board. When the amplifier is initialized, “MUTE-VA” is high and this biases C64/C65
above 5.1V via D14 and R36. This offset results in a delay of about 2 seconds from when the
amplifier turns on (“MUTE-VA” low) and when the speaker relay closes.
Low Voltage Detector
D15, D2, and R7 supply a local 5V reference and are supplied current from the unregulated
+30V supply via R32. 22VAC from the +/-30V windings is half-wave rectified via D26 and stored
by C18. R53 limits the absolute peak current to protect D26. The voltage on C18 is divided down
12
via R33 and R8 and compared against the 5V reference at U3A. If the AC line voltage falls to
around 60% of nominal (around 70VAC), the output of U3A goes low, resetting the mute and
short monostables via D5 and D12. If the +15V supply fails, D3 and D4 bias the U3A inputs such
that the amplifier is also muted. In the event of the -15V supply failing, R7 is no longer able to
pull the anode of D15 low, and this also causes U3A to go low and mute the amplifier.
THERMAL MANAGEMENT
The T-Design Heatsink/Fan cools the output devices evenly and does not collect dust on the
circuitry. The fan operates at variable speeds, controlled by output stage dissipation and
temperature data supplied from both LM35DZ’s mounted on the heatsink.
Fan Control Circuit
Referring to the 186 board: The fan voltage comes from a feedback regulator circuit formed
by U3B, Q2, Q1 and associated components. The fan supply is actually referenced to the -30V
supply, so U3A and Q3 act to shift the ground-referenced control voltage “FAST-FAN” to a -30V
supply reference. The output voltage of this regulator is adjusted via R1. D7 and C9 give the fan
an initial full fan voltage “kick” (28V) to insure the fan starts spinning. The “FAST-FAN” control line
varies from -1.6V (Slow) to -15V (Fast). Short J3 temporarily and adjust R1 for a voltage across the
fan equal to 28V.
Referring to the 170 board: The fan is never allowed to go faster than idle speed (Slow) unless
the output stage dissipation is greater than 136 watts and the heatsink temperature is above
45°C. When the output stage dissipation is greater than 136W, U4D goes low. This eliminates D1
from supplying current to U2A. This decreases the reference voltage on U2A pin7, allowing it to
work as a linear amplifier. With D1 conducting, U2A is effectively biased such that it’s output is
high and the resulting fan speed is low.
With 136W of output stage dissipation, U2A is allowed to linearly amplify the temperature
sensor voltage on U1 via R2 and R5. C5, C15, C16, and C17 provide high frequency stability to
this stage. The amplifier will linearly decrease the “FAST-FAN” voltage (increasing fan speed)
between 45°C and 65°C. Above 65°C, U2A is saturated with the fan speed maximized. D11
isolates the Channel-1 and Channel-2 U2A circuits from each other. The connection of the U2A
controllers is such that whichever channel is being used the hardest will determine the ultimate
fan speed.
Thermal Shutdown
Heatsink temperature is sensed by U1 mounted to the main heatsink (one for each channel).
The output of the sensor (10mV / °C) is compared to a 800mV reference at U2B. When the sensor
is over 800mV (80°C) the output of U2B goes low, muting the amplifier via D27 and associated,
and running the fan fast via D24. Hysteresis is built into the comparator via R3, such that the
sensor voltage must reduce to 520mV (52°C) before the comparator goes back high and the
amplifier un-mutes.
A thermostat is built into the power transformer. If the power transformer temperature
exceeds 130°C the thermostat closes and brings the “THERM” line to ground via Q1 and it’s
associated parts on the 171 board. This shorts out the 800mV reference, and the U2B output goes
low, muting the amplifier. Note that overheating of the power transformer is very unlikely but if it
does occur, the amplifier will stay muted for over an hour before the transformer cools and the
amplifier un-mutes itself.
13
The circled item numbers are shown in the parts list on page 20
Final Assembly
14
15
The circled item numbers are shown in the parts list on page 20
16
The circled item numbers are shown in the parts list on page 20
Final Assembly
17
The circled item numbers are shown in the parts list on page 21
Amplifier/Heatsink Assembly
18
The circled item numbers are shown in the parts list on page 21
Amplifier/Heatsink Assembly
19
The circled item numbers are shown in the parts list on page 21
Amplifier/Heatsink Assembly
Master Parts List 090-078-00 M2600 Assembly, 120v
Item# Part #
1
2
3
5
6
7
8
9
10
11
12
13
23
15
16
17
18
19
20
21
46
22
49
31
24
25
26
27
30
32
34
35
33
29
36
37
38
39
40
41
47
48
49
42
53
43
44
45
20
040-257-00
040-272-00
040-273-00
040-301-00
055-131-00-01
055-132-00-01
055-133-00-01
055-171-00-01
055-172-00-01
080-076-00
080-087-10
080-087-20
080-115-00
080-117-00
400-331-00
400-332-00
500-022-00
510-044-00
550-245-00
550-246-00
550-370-00
550-371-00
550-376-00
550-378-00
550-419-00
551-029-40
640-009-00
700-005-00
700-011-00
700-027-00
700-028-00
700-041-04
700-085-03
700-091-00
700-094-04
700-096-00
700-097-00
701-016-00
705-001-00
705-003-00
705-008-00
705-019-00
710-002-00
710-024-00
710-034-00
730-001-00
740-003-00
710-032-00
720-007-00
730-016-00
750-001-00
760-048-01
760-061-00
780-111-00
790-002-00
Description
Rev
Qty
CBL ASSY 24GA 3P .098 6IN
DIS 14G 1010 BRN 7.5 QDX2
DIS 14G 1010 BLU 6.5 QDX2
CBL ASSY SW PWR 23IN
PCB ASSY INPUT - 2600
PCB ASSY DISPLAY M2600
PCB ASSY PWR DIST 120V
PCB ASSY PWR SPLY M2600
PCB ASSY SPKR OUTPUT 2600
SA AMP M2600
SA HANDLE RIGHT M2600
SA HANDLE LEFT M2600
ASSY WIRE RCPT GND
SA XFMR M2600 120V
INSERT JACK BAN M-MAN RED
INSERT JACK BAN M-MAN BLK
SW RCKR ILLUMINATED
FUSE SB 30A 3AB
SCRN CHASSIS M2600
PNT SIDE RAIL RT- M2600
BRKT BRIDGE RECT HEATSINK
BRKT XFMR MOUNT M2600
PNT COVER TOP M2600
PNT SIDE RAIL LT - M2600
FAB BRKT CBLE SHLD M2600
EXTR SCRN DSPLY BZL-M2600
LC IEC SJT 20A/125V 12AWG
SEMS 8-32X1/2 PHP BLKZC
MCH 4-40X1/4 BTNSKT BLKOX
SEMS 8-32X3/8 PHP BLKZC
SEMS 6-32X1/4 PHP BLKZC
MCH 6-32X3/8 FL 100DG BLK
SCR PHP M3X6 STL BLK ZC
SEMS 8-32X3/4 PHP BLKZC
MCH 4-40X3/8 82DEG FL BLK
BOLT HEX 5/16X3-3/4 GR5 Z
MCH 8-32X1/4 FL 82DG UCUT
5-20X5/16 PHPII TYP B BLK
KEPNUT 6-32
NUT HEX-SPLD W/400-214-00
NUT LOCK 8-32
NUT STOVER LOCK 5/16X18
WASHER-SPLD W/400-214-00
WASH FLAT 5/16 HARD (USS)
WASH STL .063X.344X.688
THERMAL JOINT COMPOUND
TYRAP 8IN BLK
WASH SHLD FIBRE .317X.750
TAPE DS 30MIL X 1.0W URTH
LOCTITE 242
BUMPON ROUND BLK .63X.31
KNOB 9MM LT GRY
KNOB VOLUME AMPS
WASH RUB (W/TRANSFORMER)
BAG POLY 12 X 18 2MIL
B
B
A
A
A
A2
A1
A
A
A6
A
A
A
A
A
A
A
A
B
A
A
A
A
A
A
C
A
A
A
A
B
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
B
A
A
A
1
1
1
1
1
1
1
1
1
1
1
1
1
1
AR
AR
1
1
1
1
1
1
1
1
1
1
1
2
8
24
13
7
4
6
2
1
4
14
4
AR
2
1
AR
1
1
AR
4
1
AR
AR
4
2
2
2
1
NOTE:The Item numbers in
the first column of this page
refer to the Final Assemby
Drawings on pages 14-16
(transformer bracket)
(transformer bolt)
(transformer nut)
(transformer bottom washer)
(transformer top washer)
(transformer shoulder washer)
(transformer insulator washers)
Item# Part #
790-022-00
800-087-00
800-107-00
810-076-00
810-082-00
820-078-00
Description
Rev
POLY-SHEET 52CF X 26 4MIL
A
BOX - M2600
A
BOX SLEEVE M2600
A
INSERT - M2600
A
FOAM CORNER M2600
A
OWN MANUAL M2600 ENG/DOM
Qty
1
1
1
2
4
A 1
080-076-00 Amplifier/Heatsink subassembly
Item Part#
1
2
3
5
34
33
7
8
9
10
11
12
13
14
15
16
17
18
19
20
22
23
24
25
33
26
27
29
30
080-076-00
040-263-00
055-129-00-01
055-130-00-01
055-170-00-02
055-186-00-01
080-116-00
410-013-00
410-014-00
550-368-00
550-372-00
550-373-00
550-377-00
550-393-00
550-403-00
550-420-00
550-421-00
551-045-00
700-005-00
700-010-04
700-028-00
700-034-00
700-087-00
700-088-00
700-110-00
705-008-00
710-020-00
710-036-00
710-044-00
730-001-00
730-025-00
740-003-00
740-011-00
780-123-00
780-133-00
Description
Rev
Qty
SA AMP M2600
DIS 16GA 10C .165X2 19.5
PCB ASSY CHANNEL 1 - 2600
PCB ASSY CHANNEL 2 - 2600
PCB ASSY V-AMP PROT M2600
PCB ASSY PREDRV/FAN M2600
FAN ASSY M2600
SILPAD CUT M2600 NEW
SILPAD CUT M2600 NEW
COWLING HEATSINK M2600
BRKT FAN SHROUD M2600
BRKT SUPPORT PCB 28DEG
BRKT TO-92 MOUNTING
BRKT WIRE HARNESS M2600
FAB SEC HEATSINK M2600
FAB BRKT WIRE SHLD M2600
FAB BRKT VAMP SHLD M2600
FAB HEATSINK M2600
SEMS 8-32X1/2 PHP BLKZC
TF 6-32X3/8 PHP BLKZC
SEMS 6-32X1/4 PHP BLKZC
SEMS 4-40X1/4 PHP BLKZC
TF 4-40X5/8 TORX 1/4 WASH
TF 4-40X5/8 TORX 3/8 WASH
MCH 3-48X1/2 SKTCP SS
NUT LOCK 8-32
WASH NO.4 COMPRESSION
WASH FLT STL NO.4 .030THK
WASH SHLDR TO-220 DELRIN
THERMAL JOINT COMPOUND
LOCTITE 222
TYRAP 8IN BLK
HEATSHRINK TUBE 2:1 .50ID
INSULATOR PCB M2600
INSULATOR VAMP SHLD M2600
A6
A
A3
A2
A3
A2
A1
A
A
A
A
A
A
A
A
A
A
B
A
A
B
A
A
A
A
A
A
A
A
A
A
A
B
A
A
1
2
1
1
2
1
1
1
1
1
1
2
2
1
2
1
1
1
4
14
5
5
23
33
22
4
44
22
22
AR
AR
3
AR
1
1
NOTE: The Item numbers in
the first column refer to the
Amplfier/Heatsink Assemby
Drawings on pages 17-19
21
055-129-00 Rev A Channel 1 board
Part #
Description
Value
Reference Designator
040-261-00
040-262-00
040-265-00
040-266-00
040-267-00
040-268-00
121-077-00
123-013-00
123-045-00
123-056-00
123-125-00
150-009-00
RIB 28GA TRAN 10C .1 3IN
RIB 28GA TRAN 40C 3IN
DIS 14GA BLK/ WHT 4.5IN QD
DIS 14GA BLK/ WHT 6IN QDX2
DIS 14GA WHT 6IN QDX2
DIS 14GA BLKWHT 6IN QDX2
RESISTOR MOF
RESISTOR MOF
RESISTOR MOF
RESISTOR MOF
RES MO 3W 5% 15K OHM
RES FUS .25W 5% 2.2 OHM
150
0.33
6.8
20
15K
2.2
5%
5%
5%
5%
5%
5%
150-037-00
RES FUS .25W 5% 33 OHM
33
5%
150-045-00
150-066-00
200-036-02
200-041-00
205-003-02
211-003-00
211-009-00
220-011-02
220-025-00
220-027-02
220-047-00
301-009-00
301-010-00
302-003-00
310-033-00
310-034-00
310-042-00
310-043-00
310-049-00
310-050-00
310-055-00
310-056-00
400-077-00
400-129-00
400-231-00
400-242-00
400-243-00
450-129-00
490-021-00
501-003-00
510-041-00
601-006-00
601-008-00
RES FUS .25W 5% 68 OHM
68
5%
RESISTOR, FUSABLE, 1/4W
510
5%
CAP, METALIZED POLY, T/R
.1uF
10%
CAPACITOR POLY HI-CURRENT
0.01
10%
MICA 330PF 5% 500V
330pF 5%
CER .001UF 10% 50V AX
0.001 10%
CAPACITOR CERAMIC AXIAL
0.1
10%
CAPACITOR LYTIC RADIAL T&R
100UF 10%
CAPACITOR LYTIC RADIAL
1,000UF 10%
CAPACITOR LYTIC RADIAL T&R
10UF
10%
LYT 47UF 20% 160V RAD
47UF
20%
DIODE POWER
1N4004
DIODE POWER
1N5404
DIODE ZENER
1N4745
TRANSISTOR PNP
MJL21193
TRANSISTOR NPN
MJL21194
TRANSISTOR NPN
MJE15032
TRANSISTOR PNP
MJE15033
XSTR PNP 2SA794A
2SA794A
XSTR NPN 2SC1567A
2SC1567A
XSTR NPN 2SA1480
2SA1480
XSTR PNP 2SC3790
2SC3790
HEADER STR LCK SHRD 20P .100 X 2
FUSE CLIP 0.25 DIA PC MNT
HEADER, 2X5, MATE-N-LOCK
CONNECTOR,STR,3P,.098 X 1,SHRD
CONNECTOR,STR,2P,.098 X 1,SHRD
PCB, M2600 CH-1 AMP
MAGNET, .2THK .5DIA
RELAY, SPDT
T9AS5D12-24
FUSE 25A FB 3AG
25A
INDUCTOR, AIR CORE
1uH
10%
INDUCTOR
10uH
J1
J6
J4
J12
J8
J9
R58
R40-55
R60-68
R59
R70-73
R3 R5-6 R8 R11 R13 R16 R18 R21 R23 R25
R29 R31 R33 R36 R38
R1 R4 R7 R9 R12 R14 R17 R19 R22 R24
R26-28 R30 R32 R34 R37 R39 R57 R69
R2 R10 R15 R20 R35 R56
R75
C22 C27
C24
C30-31
C1
C2 C4 C6 C8 C15 C17
C14 C16 C18 C20
C21
C25-26
C19 C23
D5
D1-2
D3-4
Q13-14 Q16-17 Q19-20 Q23-24
Q2-5 Q7-8 Q10-11
Q1 Q6 Q9 Q12
Q15 Q18 Q21 Q25
Q29
Q22 Q28
Q27
Q26
J5
Z1-4
J2
J3
J7
Z5
Z6
K1
F1-2
L1
L2-3
Components noted with this symbol shall be replaced only by the component
specified.This is required to maintain product safety.
22
055-130-00 Rev A Channel 2 board
Part #
Description
040-262-00
040-269-00
040-270-00
121-077-00
123-013-00
123-045-00
123-056-00
123-125-00
150-009-00
RIB 28GA TRAN 40C 3IN
DIS 14GA RED 6 IN QDX2
DIS 14GA BLKRED 6IN QDX2
RESISTOR MOF
RESISTOR MOF
RESISTOR MOF
RESISTOR MOF
RES MO 3W 5% 15K OHM
RESISTOR, FUSABLE, 1/4W
150
0.33
6.8
20
15K
2.2
5%
5%
5%
5%
5%
5%
150-037-00
RES FUS .25W 5% 33 OHM
33
5%
150-045-00
150-066-00
200-036-02
200-041-00
205-003-02
211-003-00
211-009-00
220-011-02
220-027-02
220-047-00
301-009-00
301-010-00
302-003-00
310-033-00
310-034-00
310-042-00
310-043-00
310-049-00
310-050-00
310-055-00
310-056-00
400-077-00
400-129-00
400-173-00
RES FUS .25W 5% 68 OHM
RESISTOR, FUSABLE, 1/4W
CAP, METALIZED POLY, T/R
CAPACITOR POLY HI-CURRENT
MICA 330PF 5% 500V
CER .001UF 10% 50V AX
CAPACITOR CERAMIC AXIAL
CAPACITOR LYTIC RADIAL T&R
CAPACITOR LYTIC RADIAL T&R
LYT 47UF 20% 160V RAD
DIODE POWER
DIODE POWER
DIODE ZENER
TRANSISTOR PNP
TRANSISTOR NPN
TRANSISTOR NPN
TRANSISTOR PNP
XSTR PNP 2SA794A
XSTR NPN 2SC1567A
XSTR NPN 2SA1480
XSTR PNP 2SC3790
HEADER STR LCK SHRD 20P .100 X
FUSE CLIP 0.25 DIA PC MNT
CONN QUICK DISC .250
W/STABLE-LOK TABS
HEADER, 2X5, MATE-N-LOCK
PCB M2600 CH-2 AMP
MAGNET .200 THK X .50 DIA
RELAY, SPDT
FUSE 25A FB 3AG
INDUCTOR, AIR CORE
INDUCTOR
STANDOFF, SWAGE, 4-40 X .312L
68
5%
510
5%
.1uF
10%
0.01
10%
330pF 5%
0.001 10%
0.1
10%
100UF 10%
10UF
10%
47UF
20%
1N4004
1N5404
1N4745
MJL21193
MJL21194
MJE15032
MJE15033
2SA794A
2SC1567A
2SA1480
2SC3790
2
400-231-00
450-130-00
490-021-00
501-003-00
510-041-00
601-006-00
601-008-00
706-033-05
Value
Reference Designator
T9AS5D12-24
25A
1uH
10%
10uH
J3
J5
J6
R60
R40-55
R61-69
R70
R58-59 R73-74
R2 R4 R7 R9 R11 R15 R17 R19 R22 R24 R27
R29 R32 R34-35 R37
R1 R3 R5 R8 R10 R12-14 R16 R18 R20 R23
R25 R28 R30 R33 R36 R38 R56-57
R6 R21 R26 R31 R39 R71
R75
C21 C26
C25
C29-30
C1
C7 C9 C11 C13 C15 C17
C14 C16 C18 C20
C23-24
C19 C22
D4
D1-2
D3 D5
Q15-16 Q18-19 Q21-24
Q2-3 Q6-7 Q9-10 Q12-13
Q1 Q5 Q8 Q11
Q14 Q17 Q20 Q25
Q29
Q4 Q28
Q27
Q26
J2
Z1-3 Z5
J4
J1
Z4
Z6
K1
F1-2
L1
L2-3
H1-4 H6
Components noted with this symbol shall be replaced only by the component
specified.This is required to maintain product safety.
23
055-131-00-01 Rev A Input board
Part #
Description
040-258-00
040-259-00
040-260-00
100-027-00
130-062-02
140-078-00
140-082-00
140-089-00
140-090-00
140-095-00
140-123-00
145-318-00
145-331-00
145-346-00
145-389-00
145-397-00
DO NOT STUFF
RIB 28GA TRAN 20C .1 5IN
RIB 28GA TRAN 20C .1 6IN
RIB 28GA TRAN 20C .1 20IN
RESISTOR CF
RES POT 12MM HORIZ DUAL
RESISTOR TF SMT
RES TF SM .1W 5% 2K4 OHM
RESISTOR CF
RES TF SM .1W 5% 5K1 OHM
RES TF SM .1W 5% 8K2 OHM
RES TF SM .1W 5% 100K OHM
RESISTOR MF SMT
RESISTOR MF SMT
RESISTOR MF SMT
RESISTOR MF
RESISTOR MF
145-406-00
145-426-00
200-025-02
200-029-02
212-001-00
212-004-00
212-009-00
220-001-02
300-003-00
302-002-03
320-006-00
320-012-00
329-012-00
400-041-00
400-214-00
400-223-00
400-269-00
450-131-00
500-023-00
706-013-00
24
Value
120
50KC
1K6
2K4
4K7
5K1
8K2
100K
2K00
2K49
3K57
10K0
12K1
Reference Designator
5%
5%
5%
5%
5%
5%
5%
1%
1%
1%
1%
1%
RESISTOR MF SMT
15K0
1%
RESISTOR MF SMT
24K3
1%
CAPACITOR MYLAR T&R
0.56
CAPACITOR MYLAR T&R
0.22
CAPACITOR CERAMIC SMT
0.01
10%
CAPACITOR CERAMIC SMT
220PF 5%
CAPACITOR CERAMIC SMT
47PF
5%
CAPACITOR LYTIC RADIAL T&R
22UF
10%
DIODE SIGNAL SMD
DL4148
4.7V
DL5230B
OPAMP 2068E
NJM 2068
OPAMP NJM4560M
NJM4560M
OPTO-ISOLATOR,LED/CDS
VTL5C10
CONNECTOR XLR PC MTG VERT MALE
CONNECTOR JACK 1/4” VERT PC
MOUNT W/1MM LW
CONNECTOR XLR PC MTG VERT FML
TERM QDISC RTA .250 PCMT
PCB, M-2600 INPUT
SWITCH
4P3T
STDF NO.4 X .978L M/F
C22 C24
J6
J5
J11
R23 R28-29 R50-51 R65
R11 R66
R7 R67
R9 R69
R24-27 R52-53
R80-81
R8 R68
R77-79
R4 R6 R38-41 R72 R74
R35 R59
R14 R17 R44 R47
R3 R5 R21-22 R32 R56 R63-64 R71 R73
R1-2 R12-13 R16 R18 R30-31 R36-37
R42-43 R46 R48 R54-55 R60-61 R75-76
R20 R62
R15 R19 R33-34 R45 R49 R57-58
C10-11 C38-39
C12-13 C20-21 C28-29 C36-37
C4-5 C14-19 C23 C25 C30-35 C41-42
C3 C6-7 C40 C43-44
C1-2 C45-46
C8-9 C26-27 C47-48
D1-6 D9-16
D7-8
U1 U11
U2-4 U6 U8-10
U5 U7
J7 J10
J3 J12
J4 J13
J1
Z1
SW1-6
H1-2
055-132-00-01 Rev A Display board
Part #
Description
Value
130-070-00
140-057-00
140-065-00
140-068-00
140-076-00
140-081-00
140-083-00
140-087-00
140-092-00
140-094-00
140-106-00
145-389-00
145-454-00
145-472-00
145-480-00
145-527-00
145-547-00
212-001-00
212-025-00
220-002-02
220-014-00
300-003-00
304-070-02
304-071-02
311-002-00
320-012-00
323-002-00
400-077-00
450-132-00
706-033-08
RESISTOR POT 9MM HORIZ
5KB
20%
RESISTOR CF
220
5%
RESISTOR CF
470
5%
RESISTOR TF SMT
620
5%
RESISTOR CF
1K3
5%
RESISTOR CF
2K2
5%
RESISTOR TF SMT
2K7
5%
RESISTOR CF
3K9
5%
RESISTOR CF
6K2
5%
RESISTOR CF
7K5
5%
RESISTOR TF SMT
24K
5%
RESISTOR MF SMT
10K0
1%
RESISTOR MF SMT
47K5
1%
RESISTOR MF SMT
73K2
1%
RES MF SM .1W 1% 88K7 OHM
88K7
1%
RESISTOR MF SMT
274K
1%
RESISTOR MF SMT
442K
1%
CAPACITOR CERAMIC SMT
0.01
10%
CAP CER .1UF 25V 10% X7R
.1UF
10%
CAPACITOR LYTIC RADIAL T&R
47UF
20%
CAPACITOR LYTIC RADIAL KS
2.2UF 10%
DIODE SIGNAL SMD
DL4148
LED RED T1 W/.550 SPCR T/R
RED
LED GRN T1 W/.550 SPCR T/R
GRN
X-SISTOR PNP SMD
IMBT4403
OPAMP NJM4560M
NJM4560M
I.C. QUAD COMPARATOR SMD LM339
HEADER STR LCK SHRD 20P .100 X 2
PCB, M2600 DISPLAY
STANDOFF, SWAGE, 4-40 X .665L
Reference Designator
R2 R34
R17
R35 R41
R11 R24
R25 R43-49 R51
R1 R33
R12-13 R19-21 R50 R52
R16
R15
R18
R5 R10 R29 R31
R4 R7 R23 R27-28
R37 R39-40 R42
R8 R26
R3 R22
R14
R6 R9 R30 R32 R36 R38
C1 C3 C6 C10-11 C14 C19-20 C22-23
C7-9 C12-13 C15-16
C2 C4-5 C17
C18 C21
D13-20 D27
D1 D7 D21-22 D24-26
D2-6 D8-12 D23
Q1-2
U1 U6
U2-5 U7
J1
Z8
H1-3 H5-7
25
055-133-00-01 Rev A Power distribution 120V
Part #
Description
040-137-00
121-077-00
125-020-00
200-023-00
200-024-00
301-009-00
400-129-00
400-173-00
400-173-00
DIS 18GA GN/YL 96IN QD LUG
RESISTOR MOF
150
5%
RESISTOR WIRE WOUND
82
5%
CAPACITOR, POLY BOX
.001uF 20%
CAPACITOR, POLY BOX
.01uF 20%
DIODE POWER
1N4004
FUSE CLIP 0.25 DIA PC MNT
CONN QUICK DISC .250
CONN QUICK DISC .250
-00 AND -02 ASSY ONLY
CONN QUICK DISC .250
-01 ASSY ONLY
CONNECTOR,STR,3P,.098 X 1,SHRD
PCB, M2600 PWR DISTRO & AC-INRUSH
RELAY, SPDT
T9AS5D12-24
FUSE 20A SLO-BLO -02 ASSY ONLY
F1
FUSE 15A SLO-BLO -01 ASSY ONLY
F1
FUSE 25A SLO-BLO -00 ASSY ONLY
F1
400-173-00
400-242-00
450-133-00
501-003-00
510-017-00
510-018-00
510-033-00
Value
Reference Designator
J11
R3
R1-2
C1-2
C3-4
D1
Z1-2
J1-10 J12-15
J16-17
J18
J23
Z3
RL1
Z4
Z6
Z5
(100 VOLT MODELS ONLY)
(240 VOLT MODELS ONLY)
(120 VOLT MODELS ONLY)
Components noted with this symbol shall be replaced only by the component
specified.This is required to maintain product safety.
26
055-170-00 Rev A, Voltage amplifier and protection
Part #
Description
Value
Reference Designator
100-025-00
105-369-00
130-021-00
130-053-00
140-053-00
140-057-00
140-061-00
140-073-00
140-076-00
140-077-00
140-082-00
140-084-00
140-090-00
140-092-00
140-093-00
140-095-00
140-099-00
140-111-00
140-113-00
140-116-00
140-117-00
140-120-00
140-123-00
140-126-00
140-130-00
140-140-00
140-143-00
140-147-00
140-152-00
145-000-00
145-182-00
145-266-00
145-308-00
145-318-00
145-331-00
145-389-00
TEST POINT, PART OF PCB
RESISTOR CF
RES MF .125W 1% 6K19 OHM
RESISTOR POT TRIM HORIZ
RESISTOR POT TRIM HORIZ
RESISTOR TF SMT
RESISTOR TF SMT
RES TF SM .1W 5% 330 OHM
RES TF SM .1W 5% 1K0 OHM
RES TF SM .1W 5% 1K3 OHM
RESISTOR TF SMT
RESISTOR TF SMT
RESISTOR TF SMT
RESISTOR TF SMT
RES TF SM .1W 5% 6K2 OHM
RES TF SM .1W 5% 6K8 OHM
RESISTOR CF
RESISTOR TF
RESISTOR TF SMT
RES TF SM .1W 5% 43K OHM
RESISTOR TF SMT
RESISTOR TF SMT
RES TF SM .1W 5% 82K OHM
RESISTOR TF SMT
RESISTOR TF SMT
RESISTOR TF SMT
RESISTOR TF SMT
RESISTOR TF SMT
RESISTOR TF SMT
RESISTOR TF SMT
RES TF SM .1W 0 OHM
RESISTOR MF SMT
RESISTOR MF SMT
RES MF SM .1W 1% 1K58 OHM
RESISTOR MF SMT
RESISTOR MF SMT
RESISTOR MF SMT
100
6K19
10KB
200
150
220
330
1K0
1K3
1K5
2K4
3K0
5K1
6K2
6K8
8K2
12K
36K
43K
56K
62K
82K
100K
150K
200K
510K
680K
1M
1M6
0
76.8
576
1K58
2K00
2K49
10K0
5%
1%
145-414-00
145-418-00
RESISTOR MF SMT
RESISTOR MF SMT
18K2
20K0
1%
1%
145-422-00
145-426-00
RES MF SM .1W 1% 22K1 OHM
RESISTOR MF SMT
22K1
24K3
1%
1%
145-427-00
145-435-00
145-439-00
145-469-00
145-531-00
RESISTOR MF SMT
RES MF SM .1W 1% 30K1 OHM
RESISTOR MF SMT
RESISTOR MF SMT
RESISTOR MF SMT
24K9
30K1
33K2
68K1
301K
1%
1%
1%
1%
1%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
1%
1%
1%
1%
1%
1%
J1-9 J11-16 J24-26
R11 R30 R37-38
R141-144
R162
R163
R12-13 R22-23
R6
R159
R16 R19
R160
R105
R104 R140 R156
R103 R139
R48-49 R53 R77 R86 R102
R110 R152
R121
R7 R47 R51
R41-42 R67-68 R97-98
R10 R26 R57 R76
R122
R120 R158
R59 R88 R155
R147 R150
R45 R60 R123 R148-149
R3 R31 R36 R54 R107 R116
R1 R101 R106 R126 R129-130
R8 R55-56 R108 R115
R28
R9 R33 R92
R5
R15 R20 R40 R43
R93-94 R99-100 R145
R112 R114
R46
R14 R21 R39 R44 R63 R72 R146 R151 R157
R52 R64 R71 R111
R50 R58 R61-62 R73-74 R124 R128 R136
R138
R83 R132
R25 R29 R32 R34-35 R75 R78-80 R82 R84
R127 R133 R137
R119 R125
R2 R4 R65-66 R69-70 R90-91 R95-96 R109
R117
R113
R118
R17-18 R24 R27
R87 R89 R135 R161
R81 R85 R131 R134 R153-154
27
055-170-00 Rev A, continued
Part #
Description
Value
200-011-02
200-036-02
205-006-02
210-017-02
212-001-00
212-006-00
212-007-00
CAPACITOR MYLAR T&R
CAP, METALIZED POLY, T/R
MICA 30PF 5% 500V T/A
CAPACITOR, CERAMIC, T/R
CER .01UF 10% 50V X7R SM
CAPACITOR CERAMIC SMT
CAPACITOR CERAMIC SMT
0.0022
.1uF
30pF
470pF
0.01
470PF
0.047
5%
10%
5%
5%/Y5E
10%
5%
5%
212-008-00
212-016-00
212-018-00
212-019-00
212-025-00
212-029-00
220-001-02
220-004-02
220-014-00
300-003-00
CER .22UF +80/-20% 25V SM
CAPACITOR CERAMIC SMT
CAPACITOR CERAMIC SMT
CER 150PF 5% 50V SM
CAP CER .1UF 25V 10% X7R
CAPACITOR CERAMIC SMT
CAPACITOR LYTIC RADIAL T&R
CAPACITOR LYTIC RADIAL T&R
CAPACITOR LYTIC RADIAL KS
DIODE SIGNAL SMD
0.22
1000PF
10PF
150PF
.1UF
270PF
22UF
470UF
2.2UF
DL4148
5%
5%
5%
5%
10%
5%
10%
10%
10%
300-010-00
302-009-00
302-010-03
310-042-00
310-043-00
311-001-00
311-002-00
311-007-00
311-008-00
311-009-00
311-010-00
311-011-00
311-012-00
311-019-00
311-020-00
320-012-00
323-002-00
329-014-00
329-036-03
400-143-00
400-171-00
400-186-00
450-170-00
550-369-00
601-008-00
712-021-01
DIODE SIGNAL SMD
RLS245
DIODE ZENER SMD
DL5260B
DIODE ZENER SMD
DL5232
XSTR NPN MJE15032
MJE15032
XSTR PNP MJE15033
MJE15033
X-SISTOR NPN SMD
IMBT4401
X-SISTOR PNP SMD
IMBT4403
TRANSISTOR PNP SMD
2SA1415
TRANSISTOR NPN SMD
2SC3645
TRANSISTOR PNP SMD
2SA1552
TRANSISTOR NPN SMD
2SC4027
TRANSISTOR PNP SMD
2SA1740
TRANSISTOR NPN SMD
2SC4548
TRANSISTOR PNP SMD
2SB792
TRANSISTOR NPN SMD
2SD814
OPAMP NJM4560M
NJM4560M
I.C. QUAD COMPARATOR SMD LM339
IC, DEG C TEMP SENSOR
LM35DZ
NJM4200M ANLG MULTR SM
NJM4200
CONN, HDR, 3-PIN, UN-SHROUDED 0 .100
CONN, HDR, 2-PIN, UN-SHROUDED, 0 .100
CONN HDR 40P .100 X 2 STR SHRD
PCB, M2600 V-AMP & PROTECTION
BRACKET, L
INDUCTOR
10uH
RIVET
28
Reference Designator
C59
C31-32
C60
C45
C20 C25
C46
C4 C6 C8-10 C12-13 C22-23 C27 C30 C33
C35 C37-39 C41-42 C52-58 C61-62
C1 C3 C47 C51 C63
C5 C21 C24
C43-44
C11 C14
C15-18 C66
C34
C7 C48-49 C64-65
C50
C2 C19 C26 C28-29 C36 C40
D1-6 D11-14 D16-25 D27-36 D38-39
D41-42 D44-45 D47-52 D56-57
D26 D37 D40 D43 D46 D53-55 D58-60
D7 D10
D8-9 D15
Q1
Q2
Q13 Q22 Q25
Q7-8 Q21 Q24 Q28
Q4 Q9-10 Q20
Q3 Q11-12 Q15
Q6 Q26
Q5 Q27
Q14
Q23
Q16-17
Q18-19
U5-6 U8-9
U2-4
U1
U7
J21-22
J17-20 J23
J10
Z1
H1-2
L1-2
Z4-7
055-171-00-01 Rev A Power supply board
Part #
Description
Value
Reference Designator
100-077-00
123-109-00
150-037-00
200-036-02
211-009-00
220-006-00
220-029-00
220-041-00
300-001-00
301-009-00
301-010-00
301-015-00
310-007-00
400-060-00
400-133-00
400-173-00
RES CF .125W 5% 15K OHM
RESISTOR MOF
RESISTOR, FUSABLE, 1/4W
CAP, METALIZED POLY, T/R
CAPACITOR CERAMIC AXIAL
CAPACITOR LYTIC RADIAL
CAPACITOR LYTIC RADIAL
CAPACITOR LYTIC RADIAL
DIO SIG 1N4148 100V 500MW
DIODE POWER
DIODE POWER
DIODE BRIDGE
XSTR NPN 2N4401
FUSE CLIP PCMT 5MM DIA
HEADER, 2X3, MATE-N-LOCK
CONN QUICK DISC .250
W/STABLE-LOK TABS
HEADER, 2X5, MATE-N-LOCK
PCB, M2600, POWER SUPPLY
FUSE 5X20
15K
5%
3.3K
5%
33
5%
.1uF
10%
0.1
10%
2200UF 10%
2200UF 20%
15,000uF20%
1N4148
1N4004
1N5404
25A
2N4401
R10-12
R1-8
R9
C15-22
C23-24
C9-12
C13-14
C1-8
D19-20
D1-5 D10-16
D6-9
D17-18
Q1
Z1-3 Z5
J6
J3-5
400-231-00
450-171-00
510-026-00
T-3.15A
J1-2
Z4
F1-2
055-172-00-01 Rev A Speaker output board
Part #
Description
Value
400-138-01
400-173-00
400-237-00
450-172-00
SPEAKONS HORIZ 4 CKT
CONN QUICK DISC .250 W/STABLE-LOK TABS
CONNECTOR, QUAD BANANA
PCB, M2600, OUTPUT
Reference Designator
J2-4
J5-8
J1
Z1
Components noted with this symbol shall be replaced only by the component
specified.This is required to maintain product safety.
29
055-186-00 Rev A 15 Volt supply/fan drive board
Part #
100-031-00
100-049-00
100-056-00
100-061-00
100-066-00
100-068-00
100-069-00
100-073-00
100-078-00
100-080-00
100-090-00
100-097-00
121-081-00
130-021-00
211-009-00
220-001-02
220-027-02
300-001-00
301-009-00
310-002-00
310-024-00
310-050-00
320-011-00
321-001-00
321-002-00
400-078-00
400-171-00
450-186-00
550-369-00
601-013-00
712-021-01
30
Description
Value
TEST POINT, PART OF PCB
RESISTOR CF
180
5%
RESISTOR CF
1K
5%
RESISTOR CF
2K
5%
RESISTOR CF
3K3
5%
RESISTOR CF
5K1
5%
RES CF .125W 5% 6K2 OHM
6K2
5%
RESISTOR CF
6K8
5%
RESISTOR CF
10K
5%
RESISTOR CF
16K
5%
RESISTOR CF
20K
5%
RES CF .125W 5% 51K OHM
51K
5%
RESISTOR CF
100K
5%
RESISTOR MF
2K2
5%
RESISTOR POT TRIM HORIZ
10KB
CAPACITOR CERAMIC AXIAL
0.1
10%
CAPACITOR LYTIC RADIAL T&R
22UF
10%
CAPACITOR LYTIC RADIAL T&R
10UF
10%
DIODE SIGNAL
1N4148
DIODE POWER
1N4004
TRANSISTOR PNP
2N4403
TRANSISTOR PNP
2SB817
TRANSISTOR NPN
2SC1567A
I.C. LINEAR
NJM 4560
I.C. LINEAR NEG 3 TERM VOLTAGE LM 7915
REGULATOR
I.C. LINEAR POS 3 TERM VOLTAGE LM 7815
REGULATOR
CONNECTOR STR LCK SHRD 10P .100 X 2
CONN, HDR, 2-PIN, UN-SHROUDED, 0 .100
PCB, M2600, +/-15V SUPPLY & FAN DRIVE
BRACKET, L
CHOKE, POWER AXIAL
470uH
RIVET
Reference Designator
J1-2
R8
R7
R10
R6
R2
R5
R4
R9
R3
R13
R12
R11
R14
R1
C3 C5 C7-8
C2 C4 C9
C1 C6
D5-7
D1-4
Q3
Q1
Q2
U3
U1
U2
J4
J3
Z1
H1-2
L1-2
Z4-7
M•2600 amplifier modification instructions
Models affected: All M•2600 amplifiers with serial numbers “AU” or those less than DX10017.
Add this mod as part of your normal repair procedures.
Symptom: No signal, dead channel or distorted output.
Possible Cause:
1:
2:
Transistor Q5 on the V-amp protection boards may be shorted to an adjacent trace.
Transistors Q3 and Q4 on the V-amp protection boards may oscillate under certain conditions,
causing V-amp board failure, and/or failure of R57 on Ch.1 amp board and R56 on CH.2 amp
board (33Ω fuse).
Solution: Rework both V-amp circuit boards (055-170-00) as follows:
1:
2:
Replace Q5 with a new transistor and make sure it is postioned further down, away from the trace,
or : cut two traces and add a jumper wire (to bypass any possiblity of a short).
Replace R14, R15, R20 and R21 with new value resistors (to improve the reliability of the final class A
stage, comprising of transistors Q1 to Q6 and associated resistors, diodes and caps).
Safety Warning:
Caution! These instructions are for use by qualified personnel only. To avoid electric shock, do not
perform any servicing unless you are qualified to do so. Refer all service to qualified personnel.
Tools Required:
Sharp pointed X-acto knife, Phillips screwdriver, Torx and Allen drivers, needle nose pliers, safety glasses,
soldering iron suitable for surface mount work.
Parts Required:
Insulated jumper wire
311-010-00 2SC4027 Transistor, NPN, SMD
Q5
140-057-00 220Ω
Resistor, 0.1W, 5%, Thick film, SMT 0805 R15 and R20
140-084-00 3KΩ
Resistor, 0.1W, 5%, Thick film, SMT 0805 R14 and R21
Procedure: (The following modifications must be performed on both V-amp boards)
1/
2/
3/
4/
5/
6/
7/
8/
9/
Remove all cords (including the power cable and speaker outputs) from the amplifier.
Remove the amplifier subassembly from the chassis.
Remove the two V-amp boards (055-170-00) from the amplifier subassembly.
Replace R15 and R20 (from 0Ω to 220Ω).
Replace R14 and R21 (from 2kΩ to 3kΩ).
Follow step A, or follow step B, whichever you find easiest.
A/ If you have a new transistor in stock, replace Q5 and make sure it is positioned further
down, so the left leg is fully on its pad and not over the trace. Note: a new transistor is
required because unsoldering and repositioning the original transistor will thermal-stress
and weaken the part.
B/ Carefully cut the trace in two places on each board. See the diagram on the second
page. The trace should be cut exactly in the locations shown. It is not easy to get to, and
you may have to scrape off some of the white silkscreen lines in order to see the trace.
Solder a jumper wire in the position shown, on each board.
Reassemble the V-amp boards onto the amplifier subassembly.
Reassemble the amplifier subassembly into the chassis.
Perform a complete specification and safety test. Refer to the service manual for details.
M•2600 modification SSE July 2000
M2600mod.pdf, page 1 of 2
THE MACKIE FIXER • MACKIE DESIGNS SERVICE NEWS
Amplifier
Subassembly
055-170-00 V-AMP board
Solder
here
Change R14
and R15
Cut trace here
Cut trace here
Change R20 and R21
Solder an insulated wire here
M•2600 modification SSE July 2000
M2600mod.pdf, page 2 of 2
Download PDF