Package: Yes
Channels: 1
Maximum Power Per Channel: Above 200W
Brand Name: QXMY
Model Number: ma9s2 PCB
name: maranzt rear
channel: mono amplifier board
Circuit Board: Adjustable Class A
Power supply: Dc 18-50V 200W
Watt: Watt: : 250W 4Ohm
Tube series: Discrete tube amplifier
PCB style: dual pcb board
main: PCB Board only
Express delivery: Free Shipping
Type: Home Amplifier
Package: Yes
Channels: 1
Maximum Power Per Channel: Above 200W
Brand Name: QXMY
Model Number: ma9s2 PCB
name: maranzt rear
channel: mono amplifier board
Circuit Board: Adjustable Class A
Power supply: Dc 18-50V 200W
Watt: Watt: : 250W 4Ohm
Tube series: Discrete tube amplifier
PCB style: dual pcb board
main: PCB Board only
Express delivery: Free Shipping
Type: Home Amplifier
Package: Yes
Channels: 1
Maximum Power Per Channel: Above 200W
Brand Name: QXMY
Model Number: ma9s2 PCB
name: maranzt rear
channel: mono amplifier board
Circuit Board: Adjustable Class A
Power supply: Dc 18-50V 200W
Watt: Watt: : 250W 4Ohm
Tube series: Discrete tube amplifier
PCB style: dual pcb board
main: PCB Board only
Express delivery: Free Shipping
Type: Home Amplifier
Package: Yes
Channels: 1
Maximum Power Per Channel: Above 200W
Brand Name: QXMY
Model Number: ma9s2 PCB
name: maranzt rear
channel: mono amplifier board
Circuit Board: Adjustable Class A
Power supply: Dc 18-50V 200W
Watt: Watt: : 250W 4Ohm
Tube series: Discrete tube amplifier
PCB style: dual pcb board
main: PCB Board only
Express delivery: Free Shipping
Type: Home Amplifier
Package: Yes
Channels: 1
Maximum Power Per Channel: Above 200W
Brand Name: QXMY
Model Number: ma9s2 PCB
name: maranzt rear
channel: mono amplifier board
Circuit Board: Adjustable Class A
Power supply: Dc 18-50V 200W
Watt: Watt: : 250W 4Ohm
Tube series: Discrete tube amplifier
PCB style: dual pcb board
main: PCB Board only
Express delivery: Free Shipping
Type: Home Amplifier
marantz ma-9s2 rear amp mono amplifier with DC servo amp and speaker protection 2sa1943 2sc5200 tube amp
PCB Board only (no components)
Technical parameters:
Output power: AB Class is 250W / 4 ohm load; A Class is 90W/4 ohm load (Total harmonic distortion THD + N <0.1%)
Speaker Impedance: Available 4-8 ohms.
PCB size: 83 * 167MM.
Power supply: DC Dual 18-50V transformer 200 watts or more, the need to replace withstand higher voltages higher capacitance.
(Rectified and filtered power board:We note that this recommendation Oh power amplifier is rectified and filtered through dual DC power supply after, not directly connected to the transformerOutput power: 250 watts (total harmonic distortion THD + N <0.1%), DC + -50V, 4 ohm load measured under; Marantz MA-9S2-stage power supply part is +/- 45V; dual 32V rectifier transformer after + -45V;Supply voltage: DC DC dual 30-50V (higher voltage required to change the filter capacitor voltage value), the recommended +/- 45V,MAPCB size: 83X167MM, reasonable and compact layout for transit (one channel while fin);)
Description:
Independent of the supply voltage magnitude (ensure that the voltage at DC +/- 30V and above) should not change any solid resistance parameterFor the current approximately 1.5MA, 4.8MA, 7.5MA; the resulting parameters after repeated after this adjustment, operating currentWas 1000u / 50V) that can be as high pressure points, the other without changes, enter Diamond Buffer circuit portion WorkersIf the customer wants a high-voltage power supply (greater than DC +/- 50V), only the decoupling capacitor C8, C9, C10, C11 (KitNote :( high voltage capacitor volume as the replacement capacity will be relatively reduced pressure)Bass dive deep, warm bass feel very soft feeling very comfortable listeningHome large enough heat sink cooling effect can be adjusted to 500MA, fever greater Actual 100MA sound very good,
Marantz MA-9S2 prototype for the class AB amplifier quiescent current regulation 100MA-200MA was most satisfactory, if you buyIs 0.1R), the voltage regulator is 10MV the quiescent current is 100MAClose to or even better than a lot of integrated amplifier, very good Note that the output of non-inductive resistor is 0.1R / 5W (the original machine onTo ensure that at all times the midpoint voltage is substantially zero, is actually an MV level in the single digits, usually within 0-6MV, thenPlus the midpoint of the DC servo circuit so that the midpoint from debugging features of the servo circuit is output feedback will be to enter,Current), A bassoon beside the point in Q18, B point at the output side, PCB marked with; in MA-9S2 power amp on the basis ofNamely: the output voltage across the A and B point about 10MV (R33 output voltage across the resistor 0.1 ohm resistance value is divided by this staticFirst clockwise twist a few laps Security Resistors not installed backwards
(Adjustable resistor installed anti counterclockwise quiescent current will be smaller)Resistance) makes the quiescent current of about 100MA, VR1 counterclockwise quiescent current becomes large, clockwise decreases On the proposal before powerAfter completion of welding installed heat sink (note tubes and fins to be well insulated), adjust VR1 (1K Precision adjustable electricCommissioning procedure :( simply adjust the quiescent current of the line, the midpoint of free debugging)
Product pictures:
Note that this amplifier power is rectified and filtered DC power supply after a double, not directly connected to the transformer o
Recommend shop rectified and filtered with a trumpet-protected power strip:
List of components, including all components of the board
And other PCB front and back above, high-current power supply and output are treated as tin processing, input part, speaker protection, DC servo, power supply and other strictly separated, the whole place a little ground to the power supply input ground.
Friends interested in the reference circuit for learning and communication
Finish board For reference only
Buy this DIY KIT link:
product/new-mono-ma9s2-ma-9s2-marantz-rear-amp-with-DC-servo-amp-and-speaker-protection-mono/1123215_32389747504.html