The audio was a very important problem we needed to solve in order to have a quality sound and have a quality board game.
Therefore we decided to change the speaker that came with the ISD1820.
We decided to use a SONY SRS-XB, which is a very commercial and easy to use speaker. We didn’t buy it based on the fact that CRI institute facilitated to us, but any other speaker may have the same results.
The speaker has a “AUX entrance and cable”, our ISD1820 doesn’t have “AUX entrance” it only has the entrance for the voltage-ground cables. Therefore, we needed a device that allows us to attach the (voltage-ground) cables to the “AUX male connector”. We were able to find an “AUX female adaptor”
This device allowed us to introduce the other side of the “AUX male entrance” into the adaptor, in the other side of the adaptor there are points for voltage and ground, this points are the ones were the voltage and ground cables from the ISD1820 have to be welded.
It’s important to mention that we used a multimeter in order to identify the points that belonged to ground and voltage (negative and positive). You can use the multimeter sound function to recognize the ground connection and then change the function to voltage
After correctly identifying the points for ground and voltage proceed to soldering the cables to the “AUX Adaptor”. It’s very important to verify which points are for voltage and ground because there are several types of AUX adaptors.
Finally we soldered our cables into the device and tried the speaker. The audio was reproduced successfully and the volume quality was great.