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mystery hardware in autotrader merc trunk??

just that pc guy
By just that pc guy
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Go to solution Solved by mariushm,
22 minutes ago, just that pc guy said:

oh that makes sense, cuz it did have a replaced radio.. but why all this tech tho, it seems like a small chip could do all this work

It's not just an audio chip.

 

The box also includes a power supply, which converts the 10v..15v from the car's battery to something like 50v...100v which is needed to drive big speakers.

A box like the one on the right is for 2 x 500-1-00w of actual audio power, maybe even more.

12v is just too low to drive a 100-250w speaker or woofer for example, nevermind two for a stereo system... you need to boost the voltage to at least 30-50v

Unlike computer power supplies that take a high voltage and step it down to 12v, or powered speakers that may take high voltage down to 24-48v with very high efficiency - around 92-95% - these amplifiers have to take a low voltage (10-15v) and boost it up to a higher voltage, which is a more difficult and in general with lower efficiency, let's say around 85-90%

So there's more heat produced, which is why you need the aluminum case with those fins or striations, to dissipate the heat if used for long periods of time.

You can see from around 6 minutes in the video below how those amplifiers are built :

You have almost half of the insides used by the power supply and then you basically have two almost identical parts, the amplifiers for each audio channel

 

If you have some powered speakers on your PC, they're most likely in the 30-50 audio watts range and you have high voltage from mains, so the power supplies are way more simpler and efficient, and below 100-200w or audio power there are indeed audio chips that are fully integrated and can produce that much power.

But above that, you have to use multiple transistors or mosfets in parallel as you can see in the video above (you see the parts screwed down on the edges of the circuit board, directly on the heatsink of the case, to dissipate heat.

 

Posted

so im looking for a first car, saw a nice Mercedes on autotrader for 3grand, but as i started scrolling, i saw these 3 pieces of hardware, is it custom abs or something? [ps sorry mods if it isnt tech related, i didnt know where to put it :/]

Used 1991 Mercedes-Benz 500 SL ALEXANDRIA, VA 22314 - 517756097 - 23

 

 

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It's audio crap... thing on right is maybe stereo or bass amplifier , center maybe some mixer ( stereo-> 2.1 maybe)  

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Just now, mariushm said:

It's audio crap... thing on right is maybe stereo or bass amplifier , center maybe some mixer ( stereo-> 2.1 maybe)  

oh that makes sense, cuz it did have a replaced radio.. but why all this tech tho, it seems like a small chip could do all this work

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6 minutes ago, mariushm said:

It's audio crap... thing on right is maybe stereo or bass amplifier , center maybe some mixer ( stereo-> 2.1 maybe)  

Center is a crossover. 

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22 minutes ago, just that pc guy said:

oh that makes sense, cuz it did have a replaced radio.. but why all this tech tho, it seems like a small chip could do all this work

It's not just an audio chip.

 

The box also includes a power supply, which converts the 10v..15v from the car's battery to something like 50v...100v which is needed to drive big speakers.

A box like the one on the right is for 2 x 500-1-00w of actual audio power, maybe even more.

12v is just too low to drive a 100-250w speaker or woofer for example, nevermind two for a stereo system... you need to boost the voltage to at least 30-50v

Unlike computer power supplies that take a high voltage and step it down to 12v, or powered speakers that may take high voltage down to 24-48v with very high efficiency - around 92-95% - these amplifiers have to take a low voltage (10-15v) and boost it up to a higher voltage, which is a more difficult and in general with lower efficiency, let's say around 85-90%

So there's more heat produced, which is why you need the aluminum case with those fins or striations, to dissipate the heat if used for long periods of time.

You can see from around 6 minutes in the video below how those amplifiers are built :

You have almost half of the insides used by the power supply and then you basically have two almost identical parts, the amplifiers for each audio channel

 

If you have some powered speakers on your PC, they're most likely in the 30-50 audio watts range and you have high voltage from mains, so the power supplies are way more simpler and efficient, and below 100-200w or audio power there are indeed audio chips that are fully integrated and can produce that much power.

But above that, you have to use multiple transistors or mosfets in parallel as you can see in the video above (you see the parts screwed down on the edges of the circuit board, directly on the heatsink of the case, to dissipate heat.

 

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