In my opinion the design already includes enough output devices to happily run 500 watts. Just make sure your heatsink is massive, like 0.15 deg C/W or better.
Originaly there is mje15030/31 drivers and 4 pairs that worked for 300w.
I would like to know, can i use for drivers same as outputs - 2sc5200/2sa1943 ? Shuld i change some rezistor values?
I would like to know, can i use for drivers same as outputs - 2sc5200/2sa1943 ? Shuld i change some rezistor values?
Those transistors are much faster than the originally specced transistors. The circuit might not be stable with them.
Using high power devices as drivers generally isn't a good idea unless you have pre-drivers to drive them. The original driver transistors specified are up to the task of driving that many pairs, so why replace them?
If you really want to use flat pack devices, use the MJL21193/4 pairs. They are similar spec to the original MJ15024/5 devices.
Using high power devices as drivers generally isn't a good idea unless you have pre-drivers to drive them. The original driver transistors specified are up to the task of driving that many pairs, so why replace them?
If you really want to use flat pack devices, use the MJL21193/4 pairs. They are similar spec to the original MJ15024/5 devices.
Maby one simple question for you: ho to calculate that mje15030/31 is enouth to drive 6 pairs? is it possible to drive 8 pairs?
MJL21193/4 pairs are 2.5 times expensiver, that 2sc5200/2sa1943 are in my country.
MJL21193/4 pairs are 2.5 times expensiver, that 2sc5200/2sa1943 are in my country.
Change emitter resistors of power transistors to lower value, so that short circuit protection allow higher current. 0.15 Ohm should be better. 2sa1943/2sc5200 should be ok for drivers in my opinion.
regards
Adam
P.S. 6 pairs of these output transistors is much more than enough with this power. Heatsinking is crucial.
regards
Adam
P.S. 6 pairs of these output transistors is much more than enough with this power. Heatsinking is crucial.
As jaycee said, it's risky to use that much faster output devices, also if you really intend to drive 2ohms you might want the toughest devices available. These are for example the MJ15024/25.
The sc5200 has only 3A at 50v, the mj15024 has 5A.
Adams hint to change output protection is mandatory, otherwise you will never reach 500watts into 2ohm.
The mje15030/31 should do the job to drive the 6 pairs, if they are genuine. But it will be necessary to increase vas current, 6ma is too low to drive that high currents.
You might look for another amp that is already designed for 2ohms...
Mike
The sc5200 has only 3A at 50v, the mj15024 has 5A.
Adams hint to change output protection is mandatory, otherwise you will never reach 500watts into 2ohm.
The mje15030/31 should do the job to drive the 6 pairs, if they are genuine. But it will be necessary to increase vas current, 6ma is too low to drive that high currents.
You might look for another amp that is already designed for 2ohms...
Mike
I had searched for that kind of amp, but no sucsess, have you seen such amp designed for 2 ohm operation?
To be honest... No. Dealing with peak currents of ~30Amperes is not fun. This needs extra attention when doing the layout.
Another question, 500watts in a car ? Are you going for a contest ? These SPLs can get dangerous to your health. (having real 500watts rms)
I would go mosfet if i had to design such amp.
Mike
Another question, 500watts in a car ? Are you going for a contest ? These SPLs can get dangerous to your health. (having real 500watts rms)
I would go mosfet if i had to design such amp.
Mike
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