I am using these regulators in the preamp section of my amp. I'm looking for some more power and I have some larger transformers around. Currently my rails are 19v, I want to attach a transformer that will give 58v rails. I only pull a few mA from the regulators so dissipation is not an issue. If the regulators do not produce +/-12v bad things will happen in the amp. Am I safe to attach this transformer?
Those regulators will not survive input voltage that high. You will need to drop the voltage down with a preregulator or dropping resistors. If you know how much current these +- 12 volt regulators supply to the circuit just chose a resistor value to put in series with the regulator input that will give you about 18 volts or so on the input. Be sure that the resistor is high enough wattage to safely handle the heet generated.
You could just feed the regulators with the low voltage transformer you have now and power the rest of the amp with the higher voltage transformer. That way you don't need to change anything other than building a seperate highvoltage supply for the power amp.
Without knowing more about the circuit that's about all I can suggest.
Later BZ
You could just feed the regulators with the low voltage transformer you have now and power the rest of the amp with the higher voltage transformer. That way you don't need to change anything other than building a seperate highvoltage supply for the power amp.
Without knowing more about the circuit that's about all I can suggest.
Later BZ
How bad?
Things like the entire amp latching and putting large DC currents on the output.
Hi,
No, but you could use some LMxxx to preregulate.
The 78/79xx series aren't really all that good sounding but I can't see how on earth that amp is going to be more powerful by changing the VA rating of the xformer and sticking to the same rail voltage and current ratings????
Cheers,
Am I safe to attach this transformer?
No, but you could use some LMxxx to preregulate.
The 78/79xx series aren't really all that good sounding but I can't see how on earth that amp is going to be more powerful by changing the VA rating of the xformer and sticking to the same rail voltage and current ratings????
Cheers,
Hi,
So:
Yes but sticking to say, +/- 12V is not going to give more output power to the amps though, is it?
Or perhaps a misunderstanding on my part...
Cheers,
If the regulators do not produce +/-12v bad things will happen in the amp.
So:
With a new transformer he's increasing rails from 19 to 58 V.
Yes but sticking to say, +/- 12V is not going to give more output power to the amps though, is it?
Gee, I think I hear an echo.
Or perhaps a misunderstanding on my part...
Cheers,
fdegrove said:Or perhaps a misunderstanding on my part...
The +- 12 volts is for the preamp section of the amplifer. Does that help?
Later BZ
Hi,
Ah....Sorry.
Missed that part somehow, thanks guys.
Cheers,
12 v is only for preamp section, 58v for output stage, if I understand correctly.
Ah....Sorry.
Missed that part somehow, thanks guys.
Cheers,
Hi,
Want me to leave you to it then?
No problem.
Cheers,
\Echo off.
Gee, I hear an echo again
Want me to leave you to it then?
No problem.
Cheers,
\Echo off.
Hi,
LOL...
Wasn't too sure...
Question remains then if the output xsistors can live on the higher ( theoretically better) rails.
Cheers,
P.S. Funny echo thread this is...
LOL...
It wasn't you who caused echo (in both cases)
Wasn't too sure...
Question remains then if the output xsistors can live on the higher ( theoretically better) rails.
Cheers,
P.S. Funny echo thread this is...
12 v is only for preamp section, 58v for output stage, if I understand correctly.
Yes, the regulators provide power to the preamp. The output transistors are good up to 100v, caps are good.
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