My wife was using the system today when it suddenly made a "strange noise" and smoke suddenly poured out the top of the box and filled the room. Stunk the whole house out it did. Killed both of my AUD$30 sub drivers too. 
No obvious reason why it quit. Think I might just have to transplant a gainclone setup into it now.
No obvious reason why it quit. Think I might just have to transplant a gainclone setup into it now.Attachments
Circlotron said:My wife was using the system today when it suddenly made a "strange noise" and smoke suddenly poured out the top of the box and filled the room. Stunk the whole house out it did. Killed both of my AUD$30 sub drivers too.
Hi Graham, perhaps your wife is partying while you are out.
I have not seen an ETI-480 go RF before - dodgy interconnects contacts perhaps, or needs impedence compensation across the drivers ?.
Anyway you now have a reason to try those WES PP 8" drivers that we spoke of.
Eric.
Banned
Joined 2002
that isnt good!
HEY man! i have just bought an eti480 myself,!!
i was wanting to bridge it-
now im not so certain! why did this happen?!!!!!!!!!!
we need some post mortem conclosions regarding cause of death
i was just abuot to buy the toroid and other eti 480 tomorow!
i dont want my new bridged eti to destroy my 2nd hand (but new to me JBL 2226h!
HEY man! i have just bought an eti480 myself,!!
i was wanting to bridge it-
now im not so certain! why did this happen?!!!!!!!!!!
we need some post mortem conclosions regarding cause of death
i was just abuot to buy the toroid and other eti 480 tomorow!
i dont want my new bridged eti to destroy my 2nd hand (but new to me JBL 2226h!
http://homepages.paradise.net.nz/quadroph/jbl/jbl.html
circlotron-ive just made a long post in
www.diysubwoofers.org/talkshop about bridging this amp also
dont let this poor speaker from the US of A be destroyed by a crude australian amplifier,donate your information here to prevent this from happening
lol
circlotron-ive just made a long post in
www.diysubwoofers.org/talkshop about bridging this amp also
dont let this poor speaker from the US of A be destroyed by a crude australian amplifier,donate your information here to prevent this from happening
lol
Attachments
Oldie But A Goodie, And Cheap.
Graham, I have built ETI-480 modules in the past with 2SA1106/2SC2581 outputs, and MUCH better sound than 2N3055 etc.
Perhaps a better replacement would be 2SC5100 ?. etc
You also need to shift the pcb earthing point, and use a much better quality cap for LF rolloff cap.
Other mods too for the asking, and then these are (were) quite good.
Eric.
Graham, I have built ETI-480 modules in the past with 2SA1106/2SC2581 outputs, and MUCH better sound than 2N3055 etc.
Perhaps a better replacement would be 2SC5100 ?. etc
You also need to shift the pcb earthing point, and use a much better quality cap for LF rolloff cap.
Other mods too for the asking, and then these are (were) quite good.
Eric.
Righteo then...
First off, thanks for your interest, everybody.
mikee12345, That's quite a possibility, because the emitter resistors of the driver transistors got it full blast. You can see then right in the centre of the board going at a slight angle. They look about as thick (and as burnt) as a cigarette. The ones I used were wirewound ones (inductive, uh oh stability?!?!?!) because they had been cooked before because this amp had been used as a high power ultrasonic source in a previous life and was redlined for extended periods e.g 1 week day and night on several occasions. Actually those resistors have the wire windings right close to the surface and it seems they set the green caps alight first...
Another possibility is that mentioned by sajti, that is the voltage rails. The original magazine article said + / - 40v was ok at low levels but at full power they should droop to + / - 33v with a 28-0-28v 2A transformer. The (free) tranny I used has a 28v 4A and 29v 7A windings. The rails are a little lopsided but sometimes the higher one sits at 42v. With the bigger tranny the rails wouldn't droop as much as intended. Lookout safe operating area! Maybe the mains was a little high that afternoon? Seeing I wasn't home I can guarantee the volume was at max (doesn't quite clip at max setting BTW), and also my subs are pretty inefficient courtesy of the 60 gram coin collection stuck on the front to lower the resonance. Another thing, only one of the fuses popped. All of the burny stuff is not fused.
So there you go. If it was a high performance car, I would probably be boasting about it managing to destroy itself. but we here are *high* class cavemen, are we not?
BTW, here is the the thread about the subs http://www.diyaudio.com/forums/showthread.php?s=&threadid=9714&highlight=245
Post number 40 has a certain prophetic ring about it. http://www.diyaudio.com/forums/showthread.php?postid=139821#post139821
First off, thanks for your interest, everybody.
mikee12345, That's quite a possibility, because the emitter resistors of the driver transistors got it full blast. You can see then right in the centre of the board going at a slight angle. They look about as thick (and as burnt) as a cigarette. The ones I used were wirewound ones (inductive, uh oh stability?!?!?!) because they had been cooked before because this amp had been used as a high power ultrasonic source in a previous life and was redlined for extended periods e.g 1 week day and night on several occasions. Actually those resistors have the wire windings right close to the surface and it seems they set the green caps alight first...
Another possibility is that mentioned by sajti, that is the voltage rails. The original magazine article said + / - 40v was ok at low levels but at full power they should droop to + / - 33v with a 28-0-28v 2A transformer. The (free) tranny I used has a 28v 4A and 29v 7A windings. The rails are a little lopsided but sometimes the higher one sits at 42v. With the bigger tranny the rails wouldn't droop as much as intended. Lookout safe operating area! Maybe the mains was a little high that afternoon? Seeing I wasn't home I can guarantee the volume was at max (doesn't quite clip at max setting BTW), and also my subs are pretty inefficient courtesy of the 60 gram coin collection stuck on the front to lower the resonance. Another thing, only one of the fuses popped. All of the burny stuff is not fused.
So there you go. If it was a high performance car, I would probably be boasting about it managing to destroy itself.
but we here are *high* class cavemen, are we not? BTW, here is the the thread about the subs http://www.diyaudio.com/forums/showthread.php?s=&threadid=9714&highlight=245
Post number 40 has a certain prophetic ring about it. http://www.diyaudio.com/forums/showthread.php?postid=139821#post139821
do you mean,they are not specified as being Non inductive.i dont know what mine are,they arent so big anyway.
LOL
''high power ultrasonic source..''
i think since i cant buy anything else,il just give it ago,see if i can make my bridged ETI 480 blow up as good as urs..
but with speaker protection of some sort il test it on my crapy 12inch philips first :-D
i dont want my jbl on fire (600$ just bought,stil unboxed as yet)
im gona recheck my solder joints
LOL
''high power ultrasonic source..''
i think since i cant buy anything else,il just give it ago,see if i can make my bridged ETI 480 blow up as good as urs..
but with speaker protection of some sort il test it on my crapy 12inch philips first :-D
i dont want my jbl on fire
(600$ just bought,stil unboxed as yet)im gona recheck my solder joints
Banned
Joined 2002
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