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LJM Audio

This is not complicated. I often such modified to work of low voltage.

Maybe I'll consider soon after to L10D of. How much do you think DC POWER is more convenient
The issue is that when one wants to build a multi-channel amp, voltage requirements do not change, but amperage requirements can go up drastically. This is not a big deal if using a linear supply, but a SMPS does not have the same flexibility.

For example, I want to build an 8-channel amp, and I have calculated my DC requirements to be +/- 40V, but the total peak current draw will be in the neighborhood of 16 amps. For a given power level, you can get more amps if the voltage of the SMPS is lower, and therefore you don't have to buy more power supply than you need.
 
The issue is that when one wants to build a multi-channel amp, voltage requirements do not change, but amperage requirements can go up drastically. This is not a big deal if using a linear supply, but a SMPS does not have the same flexibility.

For example, I want to build an 8-channel amp, and I have calculated my DC requirements to be +/- 40V, but the total peak current draw will be in the neighborhood of 16 amps. For a given power level, you can get more amps if the voltage of the SMPS is lower, and therefore you don't have to buy more power supply than you need.


I like L15D himself. Even spent more time to modify its performance.

It works in DC +-50 V is for most of the power supply requirements,

And the output power of the sound box needs.

I think the CLASS D is the advantage of efficiency, relative simulation for power amplifier, big power some advantages are more obvious.

I don't like the small power CLASS D, CLASS T. 10 to 30 watts of power I prefer to use
LM4766T.
:drink:
 
ljm_ljm,

With the heat sink vertical on the board it doesn't look like convective airflow over the fins will be very good, since the board underneath blocks it.

Do you know what is the maximum average power that a module can dissipate when in a closed box?

And how much if the box has ventilation holes above the heat sink?

Also , what are the dimensions of the board? I searched but didn't find them, and the ebay vendors don't give them either.

Thanks
 
Ah, so it is, thanks.

Two out of three ain't bad; what's the height? :)

Is there a minimum space between adjacent boards and the amp modules and the PS?

Trying to figure out what size case is needed.


I'm interested too, there are 2 cases found on ebay for power amp. One is large about 185mm, and it is large enough, but too large for the space I have. I can only use the 165mm one, and dunno if that is big enough.
 
ljm_ljm,

With the heat sink vertical on the board it doesn't look like convective airflow over the fins will be very good, since the board underneath blocks it.

Do you know what is the maximum average power that a module can dissipate when in a closed box?

And how much if the box has ventilation holes above the heat sink?

Also , what are the dimensions of the board? I searched but didn't find them, and the ebay vendors don't give them either.

Thanks


I send connection diagram in front have a mark on size.
The radiator height about 40 MM. Plus installation about 5 MM copper column。

L15D can use 30 MM height of the radiator. If be necessary, can indicate
 

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If you are talking about this one: http://www.ebay.com/itm/110620807058?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649, you could remove the 7812 regulator, and run the +12 directly in to the printed circuit hole where it's output pin was. and the ground from the power supply would go on the regular ground point.. It would probably be a good idea to get a schematic for it as well. If you had the schematic, you could pull out the first component after the ac input connector so that the rest of the circuit was out of the way, and use AC12 as the input point (to keep it clean, and then run a wire from there to the (former) output of the 7812..
 
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