[DIY] Amplifier IC upgrade

[aidilj]

Just an update, after using the new IC for awhile the distortion starts to disappear. Started to think that the IC has gone over its burn in period, so heatsink upgrade not necessary. The speakers are in dire need of an upgrade. Driver side midrange/woofer rattles with low notes, good reason to upgrade. :top:

 

[chylee11]

Just an update, after using the new IC for awhile the distortion starts to disappear. Started to think that the IC has gone over its burn in period, so heatsink upgrade not necessary. The speakers are in dire need of an upgrade. Driver side midrange/woofer rattles with low notes, good reason to upgrade. :top:

hi bro aidilj, are you still using this player after the upgrade? how is it holding up/performing?
tempting to take same route, is the additional big cap necessary? Thanks.

 

[aidilj]

hi bro aidilj, are you still using this player after the upgrade? how is it holding up/performing?
tempting to take same route, is the additional big cap necessary? Thanks.

hi chylee11, I'm not using the head unit anymore since early this year after the carputer project, read about it here http://www.bmwclubmalaysia.com/forums/showthread.php?39713-DIY-My-E46-carputer-project . But anyhow, the carputer is using the same IC that is used in this project as the amplifier and it is working great. The factory front speakers were also swapped to aftermarket one.

If you're planning to stick to oem radio and not wanting overpowered amp then this upgrade is higly recommended. From the datasheet, only 2200uF capacitor is necessary, but I observed the LCD backlight to dim with bass pumping thus the bigger capacitor to ballast the current surge, it wouldn't hurt putting a larger capacitor for the amp. You should see the carputer project where I have multitude of giant cap, maybe my fetish. I assume you are familiar with electronics?

 

[chylee11]

hi chylee11, I'm not using the head unit anymore since early this year after the carputer project, read about it here http://www.bmwclubmalaysia.com/forums/showthread.php?39713-DIY-My-E46-carputer-project . But anyhow, the carputer is using the same IC that is used in this project as the amplifier and it is working great. The factory front speakers were also swapped to aftermarket one.

If you're planning to stick to oem radio and not wanting overpowered amp then this upgrade is higly recommended. From the datasheet, only 2200uF capacitor is necessary, but I observed the LCD backlight to dim with bass pumping thus the bigger capacitor to ballast the current surge, it wouldn't hurt putting a larger capacitor for the amp. You should see the carputer project where I have multitude of giant cap, maybe my fetish. I assume you are familiar with electronics?

im somewhat familiar, back in the college days of electronics lab! soldering and all.
i see, so the reason you put in the Cap is to buffer for the current surge of the more powerful amp in the headunit! i didnt know the higher power amp will drain out the backlight current too! sounds like it would be a significant upgrade from the current IC then.

shall find time to walk around Jalan Pasar for the parts! (and desolder+solder service if any)

i have already changed my front speakers, but finding the music lacking oomph, but i do not want to swap out headunit to put amp since car accessories shop says our car headunit are without rca out hence no amp support.

 

[aidilj]

im somewhat familiar, back in the college days of electronics lab! soldering and all.
i see, so the reason you put in the Cap is to buffer for the current surge of the more powerful amp in the headunit! i didnt know the higher power amp will drain out the backlight current too! sounds like it would be a significant upgrade from the current IC then.

shall find time to walk around Jalan Pasar for the parts! (and desolder+solder service if any)

i have already changed my front speakers, but finding the music lacking oomph, but i do not want to swap out headunit to put amp since car accessories shop says our car headunit are without rca out hence no amp support.

No RCA can still add amp, get an amp that takes speaker level input. Or the RCA sginal is the same as the one that gets into the IC, so if you are able to tap the signal that goes into the IC then you'll get your RCA/line out level signal and impedance. Good luck.

 

[chylee11]

oh, so there are certain amp that could be used.
let me check around for that, while also exploring the IC upgrade this weekend. thanks!

 

[tropos_net]

"Upgrade - TDA7560 - 4x50W quad bridge amplifier"

the sound that you are hearing now would be just different because the chip amp is of different model. until and unless the DC power supply cct is upgraded, this chip will not put out the power it was designed for.

in the spec sheet, look up the Imax, readings it needs.

 

[aidilj]

"Upgrade - TDA7560 - 4x50W quad bridge amplifier"

the sound that you are hearing now would be just different because the chip amp is of different model. until and unless the DC power supply cct is upgraded, this chip will not put out the power it was designed for.

in the spec sheet, look up the Imax, readings it needs.

Hi tropos, you seems to know what you are talking about. the DC power supply is taken directly from the battery see pin #9 from here http://www.bmwclubmalaysia.com/foru...ier-IC-upgrade&p=556522&viewfull=1#post556522 . This would be able to supply the current required to run the IC at the rated power. The only upgrade I did on the power rail is adding a filtering capacitor.

 

[tropos_net]

the pin#9 shown is the head unit pinout. do not confuse this pin for the Vcc pin of the chip. whatever appears on that pin #9 does not go directly to the Vcc leg of the chip. that means between the pin #9 on the head unit and the chip amp, there is a DC to DC convertor. if this convertor is not beefed up, it will not pump current per design.

section 2.1 of the spec sheet, the chip needs to operate between 18V to 28V on Vccc with 50V peak voltage. how are you going to do that from an average 12V car battery supply? ....ans: DC to DC convertor

 

[aidilj]

tropos_net, the IC is specifically designed for car audio application. Section 2.1 is the absolute maximum rating, this is the rating allowed before the IC is damaged but you know this already. To get the rated power only max of 14.4V (voltage when alternator is running) is needed as the amplifier input, see section 2.3 for output power.

TDA7560 is just a more capable IC than TDA7385 with the same input voltage, but of course need a little more current. Don't you agree to that?

 

[tropos_net]

you are completely confused of what Vcc and Vs values mean which are stated there in the spec sheets.
- Vs is source voltage which is refering to the outside of the box voltage requirement ie. batt feed (pin#9)
- Vcc is the positive rail which goes into the chip. the chip gets fed by the DC/DC convertor not pin#9
i have point out that pin#9 of the head unit DOES NOT go directly into Vcc pin of chip because the chip does not work with 12.2 - 14.4 Vdc.

TDA7560 is just a more capable IC than TDA7385 with the same input voltage, but of course need a little more current. Don't you agree to that?

the TDA7560 needs 10amps at full power whereas the TDA7385 needs 5amps at full power. there is a 100% increase in input current requirement so go figure if "it needs a littke more current".

 

[aidilj]

Hi tropos, to what voltage does the DC to DC converter converts the input voltage to, 12V? Thanks