lm3886 voltages

[wazzy]

anyone else ever try running one of these off 38-0-38v? i thought that i would try it out, i'm using it with my studio monitors and it sounds awesome!btw i have pretty large heatsinks and fans, essential at this voltage! no reliability issues yet!

 

[AndrewT]

38-0-38V
I presume you mean DC voltage.

That is well within the maximum stated by National for an operational amplifier.

When does the PSU measure +-38Vdc?

when the mains voltage is nominal
or
when the mains voltage is at minimum supply voltage
or
when the mains voltage is at maximum supply voltage.
or
when the amplifier is at quiescent state
or
when the amplifier is producing maximum power
or
some combination of these different operational conditions?

What is the ripple voltage at the supply pins when you measure the average DC voltage?

 

[wazzy]

yes those are the dc voltages, it is 2 volts down at maximum power, i have a power conditioner that all my av stuff goes thru so the voltage at the mains side is very stable.

 

[AndrewT]

does 2V down when under power mean
+-38Vdc quiescent and +-36Vdc when delivering power
or
+-38Vdc when delivering power and +-40Vdc when quiescent?

Does your power conditioner guarantee that your mains voltage does not vary as the Power Company allows the supply voltage to change under varying supply and demand conditions?

 

[Minion]

I ran a LM3886 off of a +/- 42v supply for a while but I had heat problems and the ocational wierd noises would creap in at high volumes ....

I ended up just useing the +/-42v supply for a TDA7293 instead which can handly these voltages and puts out considerably more power at these Voltages...
Pluss for me personally the TDA7293 is a much more musical sounding chip than any of the LM38XX chips but a bit harder to use.....


Cheers

 

[wazzy]

i have not used tda 7293 but i've used tha 7294 to me the lm3886 has a warmer sound.