Input Impedance Standby Power, less than 0.5 watts High Level, 22K ohms unbalanced, 44k ohms balanced Note: Refer to the rear panel of the C2500 for the correct voltage. Phono MM, 47K ohms; 50 to 750pF, in 50pF steps Overall Dimensions Phono MC, 25, 50, 100, 200, 400 or 1,000 ohms;...
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SECTION LOCATIONS TOP VIEW WITH COVER REMOVED AUDIO EXPANSION AUDIO BALANCED I/O TUBE DISPLAY METER LIGHT BOTTOM VIEW WITH COVER REMOVED DIGITAL AUDIO CONTROL BACKUP PS POWER...
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3 CONTROL 751457 SCH 1 of 5 DATA-IN RING R146 SLEEVE IR-IN RING 3.3V BU IR SENSOR SLEEVE IR_REAR Vout Active Low Output Address=0 LVC-AND 10uF 3.3V BU R156 22.1 .1UF I2C_SDA 3.3V BU R157 22.1 I2C_SCL 058174 RA HOLDER Disabled TUNER-ENABLE Data Port Enabled...
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C2500 TUBE PREAMPLIFIER 3 CONTROL 751457 SCH 2 of 5 J4 :1 USB+ J4 :2 USB- J4 :3 .1UF 3.3V BU J4 :4 J4 :5 Converted 3.3V BU IR_DATA_OUT Data Out No Data VDD-CORE-R J4 :6 ALL_DATA 256kbit MEMORY 3.3V BU 3.3V BU...
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3 CONTROL 751457 SCH 3 of 5 MAIN 12V_PC MAIN RING MAIN_LIGHT_PC POWER CONTROL MAIN_PC SLEEVE DGND MAIN_LIGHT_PC LIGHTS OFF LIGHTS OFF R179 MAIN_PC-EN LIGHT_CTL 2.21K 4.75K 22.1K LIGHTS OFF LIGHT_CTL_IN MAIN_PC (Micro provides pullup) R198 LIGHTS OFF LIGHT CTL IN BUFFER 100K PASS-THRU...
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C2500 TUBE PREAMPLIFIER 3 CONTROL 751457 SCH 4 of 5 133717, 1.25A Audio Sw itching J7:7 Audio Outputs 22.1 ON/OFF Power_On ? mA Max USB Audio J7:6 50k internal pulldown Low = Enable J7:5 High = Disable J7:4 18.2K J7:3...
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3 CONTROL 751457 SCH 5 of 5 TO AUDIO PCB TO AUDIO PCB TO AUDIO PCB J11:1 J11:12 J11:2 J11:11 -15V J11:3 J11:10 J11:4 J11:9 3.3V J11:5 J11:8 J11:6 J11:7 J11:7 J11:6 J11:8 J11:5 3.3V BU VCC(A) VCC(B) 3.3V BU 3.3V BU VCC(A) VCC(B)
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C2500 TUBE PREAMPLIFIER 3 CONTROL 751457 PCB...
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C2500 TUBE PREAMPLIFIER 4 AUDIO 751458 SCH 2 of 5 FROM CONTROL FROM CONTROL J12:8 J12:7 J12:6 J12:5 J12:4 J12:3 J12:2 J12:1 J13:8 J13:7 J13:6 J13:5 J13:4 J13:3 J13:2 J13:1 J3:6 3.3VBU1 OUTPUT J3:8 3.3VBU1 5.0v 5.0v 3.3VBU2 C132 DECODER 3.3VBU1...
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4 AUDIO 751458 SCH 3 of 5 1.5k 5VMC 1000µF 22pF 5VMC 1000pF MC OUT LEFT MC Jx:1 J22:3 MC LEFT -5VMC 100pF 1000pF R402 1.5k IN OUT 5VMC OPEN -5VMC J1:1 C210 100µF R404 MC LEFT 1000µF Jx:2 R403 J22:2 OPEN IN OUT...
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C2500 TUBE PREAMPLIFIER 4 AUDIO 751458 SCH 4 of 5 R109 J10:1 L MM IN J23:1 J1:1 J23:2 R107 J1:2 47.5k C224 L MM OUT J26:12 J4:1 MM-L MM PH R405 J26:6 221K J4:2 J26:10 J4:4 AGND C225 AGND R MM OUT...
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4 AUDIO 751458 SCH 5 of 5 FROM CONTROL Add Pwr On Attn, for tube DC mute?? Remove resistors C186 J16:12 J16:11 J16:10 J16:9 J16:8 J16:7 J16:6 J16:5 J16:4 J16:3 J16:2 J16:1 22pF C148 C190 22pF -15v Lef t Lef t .1µF C206 J19:1...
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6 DIGITAL AUDIO 751120 SCH 1 of 3 J11:12 J11:1 Not Used USBUSERID Not Used SPIO_MISO J11:11 J11:2 -15V Not Used SPIO_SCK Not Used SPIO_MOSI J11:10 J11:3 Not Used SPIO_CS3 Reset J11:9 J11:4 3.3V R177 OPEN J11:8 J11:5 .1uF RESET_N .01uF VDDCORE J11:7...
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C2500 TUBE PREAMPLIFIER 6 DIGITAL AUDIO 751120 SCH 2 of 3 3.3uH 3.3V .1uF J5:2 2.5V DIGITAL 4 3.3V .01uF J5-2 C153 .1uF IC CONVERTER SAMPLE RATE SMD .01uF U100 47.5 LRCLK .1uF DIG 4:COAXIAL J6:2 USB I2S Unlocked RXP3...
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8 POWER 751459 SCH POWER TRANSFORMER 23.5V J1:1 IN OUT 1.85A C104 C108 4700µF .1uF 220µF POSITIVE 18 VOLT REGULATOR J7:7 6.49k .5% J1:2 J7:6 SEC 1 J7:5 4700µF R195 J7:4 J1:3 J7:3 -23.5V -18V 1.85A -18V IN OUT -18V J7:2 C103 C107...
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C2500 TUBE PREAMPLIFIER 8 POWER 751459 PCB...
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9 TUBE 751461 SCH 1 of 3 Rename high voltage nets to closely match measurements 157V 47.5k 157V 145V 47.5k LEFT PHONO AMP 33.2k 157V 10µF 145V 10pF 1µF L MM OUT J2:12 105V J4:1 267k 475k .047µF #132352 V1:2 L MM IN V1:1 J3:1...
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C2500 TUBE PREAMPLIFIER 9 TUBE 751461 SCH 2 of 3 157V 33.2k LEFT 10pF PHONO AMP 145V 157V 1µF L MC OUT J4:12 J2:8 105V 475k 267k .047µF #132352 LEFT MC J7:1 J8:3 V3:2 V3:1 12AX7A 12AX7A 2.21M 47pF 100µF 4.75k...
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9 TUBE 751461 SCH 3 of 3 157V 146V 47.5k 157V 47.5k 146V 10µF 10µF 157V .47µF 475k L MAIN 2 .022µF .022µF J6:9 105V J6:4 267k J6:10 J6:3 #132352 130V KEC BF421-AT/P 100V L MAIN 1 V5:1 V5:2 J16:1 12AX7A 12AX7A J6:12...
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11 METER LIGHT 751135 SCH and PCB J14:12 L +5.6V J1:12 J15:12 R +5.6V J1:11 J14:11 L J15:11 R +5.6V J1:10 J14:10 L J15:10 R J1:9 J14:9 L J15:9 R J1:8 J14:8 L J15:8 R J1:7 J14:7 L J15:7 R J1:6 J14:6 L J15:6 R...
C2500 PARTS LIST INTERCONNECT Ref No. Description Part No. Ref No. Description Part No. DIODE ESD SUPPRESSOR SMD 070198 DIODE SMALL SIGNAL 4148 SMD 070199 DIODE SMALL SIGNAL 4148 SMD 070199 DIODE SMALL SIGNAL 4148 SMD 070199 DIODE SMALL SIGNAL 4148 SMD...
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PARTS LIST cont’d. DISPLAY PCB 751456 (Cont’d.) Ref No. Description Part No. Ref No. Description Part No. GROMMET 078031 R103 RES SMD0805 150K 1/8W 1% 145037 R105 RES SMD0805 150K 1/8W 1% 145037 SENSOR IR 38KHZ 3V-5V RA 121066 R106 “POT 1/4””...
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C2500 PARTS LIST cont’d. CONTROL PCB 751457 Ref No. Description Part No. Ref No. Description Part No. CAP MONO .1UF 50V 20% SMD0805 061365 DIODE ESD SUPPRESSOR SMD 070198 CAP ELECT 220UF 25V SMD 066606 DIODE ESD SUPPRESSOR SMD 070198...
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PARTS LIST cont’d. CONTROL PCB 751457 (Cont’d.) Ref No. Description Part No. Ref No. Description Part No. JACK HEADPHONE DUAL BLACK 1/8 117825 TRANSISTOR NPN A05 SMD 132333 JACK HEADPHONE DUAL BLACK 1/8 117825 TRANSISTOR NPN A05 SMD 132333 JACK HEADPHONE DUAL BLACK 1/8 117825 TRANSISTOR NPN A05 SMD 132333...
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C2500 PARTS LIST cont’d. CONTROL PCB 751457 (Cont’d.) Ref No. Description Part No. Ref No. Description Part No. R133 RES SMD0805 22.1 1/8W 1% 145003 RES SMD0805 150K 1/8W 1% 145037 R134 RES SMD0805 10 1/8W 1% 145017 RES SMD0805 47.5K 1/8W 1%...
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CRYSTAL 18.432000MHZ 20PF SMD 180065 R224 RES SMD0805 22.1K 1/8W 1% 145012 R225 RES SMD0805 150 1/8W 1% 145019 FIRMWARE V1.00 C2500 230039 R226 RES SMD0805 22.1K 1/8W 1% 145012 ASSY SMD CONTROL 710173 R231 RES SMD0805 22.1 1/8W 1%...
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C2500 PARTS LIST cont’d. AUDIO PCB 751458 (Cont’d.) Ref No. Description Part No. Ref No. Description Part No. CAP 100PF 50V SMD0805 061316 C130 CAP 100PF 50V SMD0805 061316 CAP 100PF 50V SMD0805 061316 C131 CAP 100PF 50V SMD0805 061316...
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PARTS LIST cont’d. AUDIO PCB 751458 (Cont’d.) Ref No. Description Part No. Ref No. Description Part No. C200 CAP ELECT 470UF 16V 066508 DIODE SMALL SIGNAL 4148 SMD 070199 DIODE SMALL SIGNAL 4148 SMD 070199 C201 CAP ELECT 470UF 16V 066508 C202 CAP MONO .1UF 50V 20% X7R SMD0805 061365...
If a shipping carton or 404080 #10-7/16” Flat washer any of the interior part(s) are needed, please call or write Cus- tomer Service Department of McIntosh Laboratory. Refer to page 3. Please see the Part List for the correct part numbers.
The continuous improvement of its products is the policy of McIntosh Laboratory Incorporated, who reserve the right to improve design without notice. Because of the constant upgrading of McIntosh products’ circuitry and components, the Company cannot insure, and does not warrant, the accuracy of the within schematic material, which is intended for information only.
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