Thread: need amp turn on delay, speakers pop

this might be what you are looking for:
http://store.mp3car.com/Micro_Shutdo..._p/pwr-007.htm

while it is really for turning the computer on/off, you might be able to use it to turn on the amps after the computer is booted up.

one of the features is that it senses wheather the computer is turned on, this might cause problems keeping the amps turned on. but no one knows until it is tried.

if you would like to build a circuit, there is always a time delay circuit:


I’ve selected the 555 timer due to following reasons.

1. Timing from microseconds through hours.
2. Ability to operate from wide range of supply voltages.
3. High temperature stability.
4. Easily Available.
5. Its triggering circuit is quite sensitive.

This is basically a monostable. The external timing capacitor C2 is held initially discharged by the timer. The circuit triggers upon receiving a pulse to its pin 2 when the level reaches 1/3 Vcc. Once triggered., the circuit will remain in that state until the set time is elapsed or power to the circuit cuts off. The delayed period in seconds is 1.1 C2.R1 where R1 is in megohms and C2 is in microfarads. In practice, R1 should not exceed 20 M. If you use an electrolytic capacitor for C2, select a unit for low leakage. The time delay may have to be adjusted by varying R1 to compensate for the wide tolerance of electrolytics.


from this page, 4th item down.
http://www.electronics-lab.com/proje...042/index.html

This is what I use:

http://www.mp3car.com/vbulletin/soft...r-powerup.html

When I went to my friends audio shop today, he told me I should use a DEI 528t pluse timer relay module. adjustment from 1sec- 90sec
https://www.directedstore.com/cgi-bi...ategory%3DA_SE

Damn! I need to raise my prices. LOL The input on that looks like it takes a negative pulse like from an alarm or door switch, and then stays on for the programmed time (1-90 seconds) then turns off. Might not be good for this application.

I hated that popping so much this is what i did on my setup..
On my soundblaster usb card I tapped of the status power led and ran that to a switching transistor, then from that i ran out to a relay, and in turn out to the amps! ohh man its great smooth turn on and off not a bit of noise just a soft turn on!! I can get the number of the transistor i used it was aprox a 3-5 volt input range.. Or I could post a diagram if your interested... Just another idea to think about!?

That's a great idea. The LED probably goes off before the output drivers lose power to cause the pop. Perfect timing. So something like this? The resistor represents the internal LED driver dropping it to 2.2V or so, 5V reed relay with protection powered by the internal 5V off the USB connection.



Edit: 2 options. 2nd is simpler.

Yes sir Except I used the 12 volt switching side your design looks even better i just didnt want to chance loading anything off the 5vlt side, I have had bad luck lol!!

It really is perfect timing, on right after the drivers load and power up the unit, and off right as windows is hybernating/ shutting down... I was just sitting in the car one day brainstorming how would be the absoulte best way to rid the system of those horrble issues it already blew the finals in one of my sub amps not no mention how ghetto it sounds :grrr: GL!!

HAHA OMG NINGA EDIT NICE

Haha, yeah, was just thinking about the optocouplers I use for that kind of thing. Either way I try to isolate the circuits in case people hook things up wrong, so no 12V going into the 5V circuit anywhere. And relays without the diode could be dangerous. Keep it simple