Attached are the schematics
for LM3886 and LM1876 amplifier : I added DC blocking capacitor (1uf and 47k) and a high pass filter with 470pf and 680Ohm to amplifier boards externally by removing one of the resistor and soldering directly on backside of PCB. I also added 220pf capacitor between the input pins,
I don't have schematic of LM1876, but i used the same as given in datasheet.I directly created board for this amplifier as i was not able to find proper eagle library for lm1876, one which i used does not align with the pins of lm1876, I somehow managed to stretch the pins of IC and mounted it on the PCB.
I have not used any of the 3 pin connectors for connecting potentiometer shown in active filter schematic as it was resulting in lots of noise, I just shorted the pins and used final output pins of filter board to connect potentiometer.
Values of resistor and capacitors are calculated using esp-lr13.exe program available on this link (Linkwitz-Riley Electronic Crossover)
Crossover frequencies chosen are below
Sub : 112.5 Hz (lowpass)
Mid Woofer : 75~900 Hz (Bandpass)
Mid Range : 750 ~ 3500 Hz (Bandpass)
Tweeter : 3500 Hz (HighPass)
1n5408 board is used for power supply of midrange and tweeter (2 x LM1876)
2 x MUR860 board are used for Subwoofer and mid woofer amplifier (4 x LM3886)
1n4008 for active filter power supply.
for LM3886 and LM1876 amplifier : I added DC blocking capacitor (1uf and 47k) and a high pass filter with 470pf and 680Ohm to amplifier boards externally by removing one of the resistor and soldering directly on backside of PCB. I also added 220pf capacitor between the input pins,
I don't have schematic of LM1876, but i used the same as given in datasheet.I directly created board for this amplifier as i was not able to find proper eagle library for lm1876, one which i used does not align with the pins of lm1876, I somehow managed to stretch the pins of IC and mounted it on the PCB.
I have not used any of the 3 pin connectors for connecting potentiometer shown in active filter schematic as it was resulting in lots of noise, I just shorted the pins and used final output pins of filter board to connect potentiometer.
Values of resistor and capacitors are calculated using esp-lr13.exe program available on this link (Linkwitz-Riley Electronic Crossover)
Crossover frequencies chosen are below
Sub : 112.5 Hz (lowpass)
Mid Woofer : 75~900 Hz (Bandpass)
Mid Range : 750 ~ 3500 Hz (Bandpass)
Tweeter : 3500 Hz (HighPass)
1n5408 board is used for power supply of midrange and tweeter (2 x LM1876)
2 x MUR860 board are used for Subwoofer and mid woofer amplifier (4 x LM3886)
1n4008 for active filter power supply.
Hi Kuldeep,
I got the PCB made 3 years ago from AV process , pune
Av Process, Sadashiv Peth, Pune, India on Askme
I started this project 3-4 years ago, but left it in the middle because i was tired finding out the components in local market. Fortunately i got my enthusiasm back 2 months ago, did lots of travelling in pune local electronics market and lamington road (mumbai) and finally I finished this project
I almost explored most of online resources(pics and schematics) for DIY chipamps, I have seen your project webpage earlier, it looks awesome!
Thanks,
Aniruddha
I got the PCB made 3 years ago from AV process , pune
Av Process, Sadashiv Peth, Pune, India on Askme
I started this project 3-4 years ago, but left it in the middle because i was tired finding out the components in local market. Fortunately i got my enthusiasm back 2 months ago, did lots of travelling in pune local electronics market and lamington road (mumbai) and finally I finished this project
I almost explored most of online resources(pics and schematics) for DIY chipamps, I have seen your project webpage earlier, it looks awesome!
Thanks,
Aniruddha
saw ur work on google+ ......awesome work man.......
Here is my existing stereo system.....to which i need to add the SUB.....
http://www.facebook.com/media/set/?set=a.1697852484611.2095179.1186835873&type=3
Here is my existing stereo system.....to which i need to add the SUB.....
http://www.facebook.com/media/set/?set=a.1697852484611.2095179.1186835873&type=3
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