24 dB/Octave 2/3-Way Linkwitz DC on output after power cut

Hello

i build this 24 dB/Octave 2/3-Way Linkwitz from http://sound.westhost.com/project09.htm

i made it 3 way and i have changed all opamp for OPA627
it seems to be working just fine. but then today i acidently pulled the AC plug, from the filter while the amp was still on. 1 sec. later! a Bad sound! and smoke! from my new Neo3PDR:bawling:



so i disconecntet the amp and mesured no DC on output when power on. but when i turn it off for 1-2 sec. 1-1.5volt DC on all output:xeye:

How can i cure this??
 
Hello

I’m back whit a new problem, worse i think.

My crossover has been working fine for a I think ½ a yeah. But just 5 minutes ago while playing music. A LOUD, VERY LOUD horrible sound, I don’t believe my speakers can get any louder than that. Very nasty sound I believe it was between 60-3000Hz. it was only in the one channel, I ran over and turned it off. When I turned I back on it was gone. What can cause this? A bad solder join? Or a bad cap? Glad the speaker id not blow.

Hope someone can help
 
i meant to say ::: is the overall sound output from the amplifiers system improved in terms of quality of sound after the music signal is passed from lr 24db xover??

i have jus completed the circuit on pcb(12db/octave lr from rod elliot's site).but m scared to power it up.reason being that i didnt understand in his article that how to connect the 100nf caps near op amps on power rails.if u know please tell me.
is it like,for each opamp,take a 100nf cap,solder one leg at pin 4 and other leg at pin 8????? if its something else way then how??
hence i asked for pcb layout or pics of the built x-over

any help welcome.
 

kkchunghk

Member
2004-10-06 10:46 am
driver choice

Hi Calebay,
This may be a bit off subject, so I say sorry first. I have got the parts to build to 2-way versionof the crossover with OPA2134. But I'm hesitating on the cut off frequency. ESP suggests a cut off at 310Hz for a 2-way crossover, and this seems to be an odd choice when finding drivers to match. May I ask if yours is a 2-way or 3-way crossover, the cut off frequencies, and the drivers chosen, and the million-dollar question - is the sound much better with than without the active crossover? Oops, seems a mouthful to ask.

Cheers,
KK
 

wxn

Member
2003-09-24 9:26 am
Vilnius
sagarverma said:
i meant to say ::: is the overall sound output from the amplifiers system improved in terms of quality of sound after the music signal is passed from lr 24db xover??

i have jus completed the circuit on pcb(12db/octave lr from rod elliot's site).but m scared to power it up.reason being that i didnt understand in his article that how to connect the 100nf caps near op amps on power rails.if u know please tell me.
is it like,for each opamp,take a 100nf cap,solder one leg at pin 4 and other leg at pin 8????? if its something else way then how??
hence i asked for pcb layout or pics of the built x-over

any help welcome.

Yes, you could solder 100n caps between 4 and 8 pins, you could put them between 4/8 legs and ground. Or you could do both :)
 
Hi kk

Cut off at 310Hz appears to be the crossover frequency that he suggests for a 3-way. Between a bass unit and a midrange. In a normal 2 way design it will be a lot higher. But it all depends on the drivers you chose to use. What I use in my case is a Eton 11” crossed over at 150hz to a Fostex FX200 crossed over at 6000hz to a Neo3PDR. I’m happy whit the sound. I can’t compare it to passive crossover because I have only tried the active one whit these speakers.

sagarverma
I can’t post my PCB sorry it got deleted last time I reinstalled windows I have a low quality pic. but its 250kb.. how do i post pic bigger than 102400 bytes?
:xeye: