My older Alpine MRV-F307 4-channel amp is in need of repair... While it's torn apart, I might as well tweak it a bit! I am currently using the line level inputs on the amp as I don't want to change my Headunit from stock (It just invites thieves). My plans are:
1) Use an LOC rather than the amps speaker level inputs. I'm thinking of building my own so that I can control the quality of components. I've thought of tapping into the Headunit ahead of the amplifier stage, but I like the idea of a balanced output because interference is a big problem (Cell phones, etc...). Why is the impedance of an LOC so low (~20 ohms), can I go higher (~100ohms) to ensure that the headunit amp operates in Class A?
2) Replace any signal path electros with MKP's
3) Add some capacitance to the rails. Does this work with an SMPS supply? Can I add some 1uF low ESR snubber caps or will this promote oscillation of the supply?
4) Increase the bias
5) Use good shielded cable from HU to amp. What is recommended? I have been thinking of the following:
- Cat 5e (One channel per twisted pair) Cross talk?
- Cat 5e (One channel per cable, solid=+ve, striped=-ve) Capacitive load?
- Balanced XLR style wire (Expensive)
But, before I can do anything, I would like to find a schematic... I've searched all over the place but can't find anything. Does anyone know where I can find a schematic for this amp?
Thanks,
Ryan
1) Use an LOC rather than the amps speaker level inputs. I'm thinking of building my own so that I can control the quality of components. I've thought of tapping into the Headunit ahead of the amplifier stage, but I like the idea of a balanced output because interference is a big problem (Cell phones, etc...). Why is the impedance of an LOC so low (~20 ohms), can I go higher (~100ohms) to ensure that the headunit amp operates in Class A?
2) Replace any signal path electros with MKP's
3) Add some capacitance to the rails. Does this work with an SMPS supply? Can I add some 1uF low ESR snubber caps or will this promote oscillation of the supply?
4) Increase the bias
5) Use good shielded cable from HU to amp. What is recommended? I have been thinking of the following:
- Cat 5e (One channel per twisted pair) Cross talk?
- Cat 5e (One channel per cable, solid=+ve, striped=-ve) Capacitive load?
- Balanced XLR style wire (Expensive)
But, before I can do anything, I would like to find a schematic... I've searched all over the place but can't find anything. Does anyone know where I can find a schematic for this amp?
Thanks,
Ryan