Cool, I think I might have to do that. I have the service manual and circuit diagram of the receiver, so hope i don't need to open up it again.
But I'm worried with the quality of these, i have seen this in locally made amps and standalone speakers in the market.
The sound quality is good, the appearance can be crude.
I use this in my car, with USB stick, and tried on big speakers also, quite clear.
In fact, I have one of these local amps at home with Sony speakers, and it is the speakers which decide the quality.
You can check the specifications from the Chinese makers.
I use this in my car, with USB stick, and tried on big speakers also, quite clear.
In fact, I have one of these local amps at home with Sony speakers, and it is the speakers which decide the quality.
You can check the specifications from the Chinese makers.
As i remember ,those bt have speaker output and aux input , has no line-out to connect to amplifier properly . Connection from speaker output to line-in is mostly noisy , best heard at pause between songs or if you make volume quiter at bluetooth. Better would be module with line in ,line out ,no amplifier .
This is a sample of the IC used, the FM modules sold here have line in, front aux., 5V, and line out connections.
No amplifier, they are used in amplifiers now, as a lot of people use memory sticks / cell phones, so playing music through memory device or Bluetooth is common.
The module output is connected internally to the amplifier section, the module acts as the pre-amp section.
Some amps have switches, and can select mic. in and so on also.
But as a pre-amp alone, it is quite acceptable, and for that price, I am content.
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You can see fins on 7805 in the middle of the PCB, that is for the FM module.
The amp is local, 12 Volts can come from vehicle battery also, and there is a 1/4" mic jack in front, so you can use as a PA system also.
Mark the fact that the stamping tool has letters on it, mass production, one operation reduced...See the back wall in the photo, where the connectors are.
$10 only, chips are CRC China made 4440, the original Sanyo were good to 19W in BTL.
These get plenty loud, and sound is clear through my Sony speakers.
I had to rework all the joints, and one capacitor fell off, extreme right, I put a Keltron, the orange one at right.
That made the chip amp go into overgain, and it cost me 25 Rupees, 30 cents, replaced it.
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