power supply crossover diy

[nek antunes]

My crossover have 28 ampop.
My sistem is 7.1, with 2 way amplifier for each speaker.

My question is what should my power transformer? 20VA is enough?

 

[JonSnell Electronic]

With absolutely no detail, all I can say is V times I or VI = Watts, so if your system produces less than 20Watts, yes.

 

[fpitas]

Power supply crossover? I know all those words, but together they are just confusing.

 

[DUG]

7.1 system-bi-amped

=15 amplifiers (min)

@ 20VA = 1.3W per amplifier

Seems a little light on the power but it could be.

I would say with absolutely no detail...No

We are both guessing and making assumptions.

We both agree that there is not enough detail to provide a definite answer.

 

[nek antunes]

excuse my English
My amp is for lm1875 tweeter and woofer for lm3886.
The system is 7.1.
Bi amplified.
My crossover has 28 Ampop (NE5532). Linkwitz-Riley Electronic Crossover
I do not know which the power transformer, for the power suplly crossover.
thanks

 

[nek antunes]

DUG thanks for your answer.

20VA sounds good

 

[fpitas]

excuse my English
My amp is for lm1875 tweeter and woofer for lm3886.
The system is 7.1.
Bi amplified.
My crossover has 28 Ampop (NE5532). Linkwitz-Riley Electronic Crossover
I do not know which the power transformer, for the power suplly crossover.
thanks

So, you are building a power supply for an electronic crossover? 20VA may well be enough in that case. The NE5532s can draw as much as 16mA per chip, so 28 will require 448mA maximum. As long as your power supply can handle that, you should be fine.

 

[JMFahey]

Your 28 Op Amps need almost 1/2 Ampere which considering +/-15V rails mean 15W or VA.
But you tell us nothing about the PSU, whether it's raw or regulated, etc.

By the way; you built a dozen stereo crossovers and run 14 shielded cables to separate amplifiers?
Or you built a rack for all those amps and run 4 wires for each speaker?

 

[nek antunes]

okay
My crossover have 10x20cm
I'll buy a toroid of 15-0-15 20VA

thanks for answers

 

[nek antunes]

I built a rack for all those amps and run 4 wires for each speaker.

I really liked the sound of this crossover.

I used the LM337 lm317 and with 4x 1000uF on each way.