hello all i am relatively new to this forum and i have found some very usefull information here , but i can t seem to find anyone talking about one of the problem that i have encountered.
so here s the situation, i am building a portable speaker and at first i was using the SE configured tda7492 amplifier and a oval 300w 4ohm 2-way car speaker and i connected the a tweeter and woofer seperatly each i one chanel with a 3ohm resistor i series with a tweetwe r.and that sounded good for about one day and then it started sounding like **** with lots of distortion, and i thought that was because of unbalanced loads cause tweeter was 4ohm and woofer was 3 ohm .
then i took a new tda7492 and connected the speaker as it was tweeter and woofer i series (4 ohms), and connected speaker to only one chanel of the amplifier , that worked well but not for long.then i decided to change the output filter on tda7492 withe the one thats on their official datasheet with film capacitors and bigger coils. and that diddent help either .
lastly i ordered a tpa 3118 pbtl amp i hope that it would work this time and i worked the same two days and then started giving loads of distortion. i am starting to think that the speaker could be the problem becasue it was not new when i got it. it was used quite a lot for about 3-4 years. the speaker is connected as follows i ve got 12v 10ah battery made from old laptop batteries which goes into this boost converter 200W 6 35V to 6 55V DC DC Converter Boost Charger Power Converter Module SY | eBay
which boosts to 21v and then it goes into amp. the audio signal goes to lm1036 pre amp and then into amplifier.the pre-amp and the amplifier share the same power maybe that could be problem i don t know. please help thank you .
so here s the situation, i am building a portable speaker and at first i was using the SE configured tda7492 amplifier and a oval 300w 4ohm 2-way car speaker and i connected the a tweeter and woofer seperatly each i one chanel with a 3ohm resistor i series with a tweetwe r.and that sounded good for about one day and then it started sounding like **** with lots of distortion, and i thought that was because of unbalanced loads cause tweeter was 4ohm and woofer was 3 ohm .
then i took a new tda7492 and connected the speaker as it was tweeter and woofer i series (4 ohms), and connected speaker to only one chanel of the amplifier , that worked well but not for long.then i decided to change the output filter on tda7492 withe the one thats on their official datasheet with film capacitors and bigger coils. and that diddent help either .
lastly i ordered a tpa 3118 pbtl amp i hope that it would work this time and i worked the same two days and then started giving loads of distortion. i am starting to think that the speaker could be the problem becasue it was not new when i got it. it was used quite a lot for about 3-4 years. the speaker is connected as follows i ve got 12v 10ah battery made from old laptop batteries which goes into this boost converter 200W 6 35V to 6 55V DC DC Converter Boost Charger Power Converter Module SY | eBay
which boosts to 21v and then it goes into amp. the audio signal goes to lm1036 pre amp and then into amplifier.the pre-amp and the amplifier share the same power maybe that could be problem i don t know. please help thank you .