1pc Marantz 7-Tube Phono Amplifier(MM) RIAA KIT DIY
DIY KIT Project：
DIY kit: Contains the PCB and the components needed on the PCB, but does not include the power transformer .
To complete this project, high level knowledge of electronics and rich experience in terms of soldering and testing are required.
Due to time zone and language communication restrictions, we can only provide limited technical support, and you need to solve problems by yourself.
DIY kit: Contains the PCB and the components needed on the PCB, but does not include the power transformer .
To complete this project, high level knowledge of electronics and rich experience in terms of soldering and testing are required.
Due to time zone and language communication restrictions, we can only provide limited technical support, and you need to solve problems by yourself.
Summary
Ma7-Phono Amp(MM), It is based on the core circuit of the Marantz 7 phono amplifier.
Ma7-Phono Amp(MM), It is based on the core circuit of the Marantz 7 phono amplifier.
Tech highlights：
Compared with the commonly reproduction of Marantz 7, we improved:
1、High Voltage：Two-stage buck regulator filter, Two low-pass filter (with a corner frequency of 1.6Hz&16Hz) prevents power noise from being introduced into the amplifier. Provide purer power supply (close to battery).
2、The high-voltage power supply uses MOSFET as pass transistors, which have a sense of tube sound characteristics but rejecting the rectification and regulation noise.
3、high-voltage soft-start feature is included which will take about 5 second to reach the designed voltage protecting the tube from any voltage shock.
4、heater-voltage soft-start feature for vacuum heater is included which will take about 5 second to reach the designed voltage(12.6v) protecting the tube from any voltage shock and extending life.
5、all-in-one design, single-point grounding, ground resistance is close to the 0.02 ohm resistance value, low noisedesign.
6、PCB is Small with double-sided smt.
7、The triangular tube layout reduces the number of dual-channel common tubes, further improves the separation and reduces crosstalk.
8、Mirror HR-pin, please shift the tube counterclockwise every three months, reduce tube magnetization, further extend tube life and save money.
9、More cost-effective sound modification plan.
PCB SIZE: 153x153x1.6mm 1oz Cu, HASL with lead.
Power requirements:
Heater Volt: AC13~15V, I ≥ 0.8A; Best:14VAC@1A
High Volt: AC220~260V, I≥0.02A; Best:240VAC@0.05A
Compared with the commonly reproduction of Marantz 7, we improved:
1、High Voltage：Two-stage buck regulator filter, Two low-pass filter (with a corner frequency of 1.6Hz&16Hz) prevents power noise from being introduced into the amplifier. Provide purer power supply (close to battery).
2、The high-voltage power supply uses MOSFET as pass transistors, which have a sense of tube sound characteristics but rejecting the rectification and regulation noise.
3、high-voltage soft-start feature is included which will take about 5 second to reach the designed voltage protecting the tube from any voltage shock.
4、heater-voltage soft-start feature for vacuum heater is included which will take about 5 second to reach the designed voltage(12.6v) protecting the tube from any voltage shock and extending life.
5、all-in-one design, single-point grounding, ground resistance is close to the 0.02 ohm resistance value, low noisedesign.
6、PCB is Small with double-sided smt.
7、The triangular tube layout reduces the number of dual-channel common tubes, further improves the separation and reduces crosstalk.
8、Mirror HR-pin, please shift the tube counterclockwise every three months, reduce tube magnetization, further extend tube life and save money.
9、More cost-effective sound modification plan.
PCB SIZE: 153x153x1.6mm 1oz Cu, HASL with lead.
Power requirements:
Heater Volt: AC13~15V, I ≥ 0.8A; Best:14VAC@1A
High Volt: AC220~260V, I≥0.02A; Best:240VAC@0.05A
Product configuration：
1pc Marantz 7-Tube Phono Amplifier(MM) RIAA KIT DIY.
1pc Marantz 7-Tube Phono Amplifier(MM) RIAA KIT DIY.
Based on the well-tested board on the standard version kit, we verified all key points' voltage, and used the signal generator and oscilloscope for analog waveform double verification. We will not use this board for listening test.
Schematic & key point of debugging
PCB comes with component parameters for easy installation.
We only refer the schematic of the amplification part of the circuit. If you need full circuit parameter, please read the component value with the PCB by yourself; we do not provide additionally.
please keep test point voltage close enough to it, +-20% is also permitted
Schematic & key point of debugging
PCB comes with component parameters for easy installation.
We only refer the schematic of the amplification part of the circuit. If you need full circuit parameter, please read the component value with the PCB by yourself; we do not provide additionally.
please keep test point voltage close enough to it, +-20% is also permitted
