Ah HA!  Now you are reaching me.  I new about the coil part but the first half of it, now i gotcha... 

 

So, I'll be the first to say this.. why don't we just go ape shit on tinsel lead?

 

If we are to assume all subwoofer companies are aware of what can happen, why not go overkill on the tinsel leads, even though many here will think it's not overkill if it's going to save the sub from partial failure?

 

Not blaming you at all but if we are assume that most amps out there will be in the hands of the customer, we should make damn sure our speaker products are capable of handling such environments.

The btl's have 16 tinsel leads, double the size and strand count, which is 4x what any other manufacture is using and there is still the occasional issue. Surface area and 'more tinsel lead' isn't going to solve the issue

 

Something for you to chew on..

 

..if the problem at hand is a result of those polluting up the creek..why should i have to re-engineer my fishing pond to accommodate for the people that live up the creek from my pond and are too cheap/uneducated to build a bridge? they are the ones dumping oil and contaminants from their trucks in the water and killing off all of my fish in my pond that is fed by the creek that they pollute..but i'm suffering the consequences of them squeezing a dollar?

 

The 'most ideal' way I mentioned of doing it before is patented and unavailble.

because the market is flooded with creek pollution.

 

 

Let's go this route-  Since i'm as electrically inclined as a plumber, lol, lets see where this goes-

 

The only wire between the amp and col is the Tinsel lead and speaker wire being used.

 

Well, apparently the speaker wire never gets destroyed so we'll focus on the tinsel leads... 

 

This is a.. well, gay long shot here but lets see where it goes.. 

 

So, we destroy a sub.. we get a recone.

 

What would happen if we cut the lead between the Tinsel Lead and the coil and solder it to a rectifier diode of let's say 70A and lets say around 110-130vac.

 

If we force the current and voltage to stay in the coil at all times.. would that solve the problem?

 

Now, where the diode would be at isn't relevant right now, just the thought.

 

 

Like i say before and i think you agree too, most to all amps out there may have this problem so instead of building to what is known to manufacture but isn't, build to what's out there and common.

I'll have to think about that over the weekend, going on 18 hours of hard work now and not in the mood to start thinking about something like that

because the market is flooded with creek pollution.

 

 

Let's go this route-  Since i'm as electrically inclined as a plumber, lol, lets see where this goes-

 

The only wire between the amp and col is the Tinsel lead and speaker wire being used.

 

Well, apparently the speaker wire never gets destroyed so we'll focus on the tinsel leads... 

 

This is a.. well, gay long shot here but lets see where it goes.. 

 

So, we destroy a sub.. we get a recone.

 

What would happen if we cut the lead between the Tinsel Lead and the coil and solder it to a rectifier diode of let's say 70A and lets say around 110-130vac.

 

If we force the current and voltage to stay in the coil at all times.. would that solve the problem?

 

Now, where the diode would be at isn't relevant right now, just the thought.

 

 

Like i say before and i think you agree too, most to all amps out there may have this problem so instead of building to what is known to manufacture but isn't, build to what's out there and common.

 

 

The problem is that you're dealing with AC voltage, the rectifier is going to do it's job filtering no matter which direction the current is coming from (whether it's a half wave or full wave rectifier, it won't matter) so you're going to rectify the output from the amp as well.

 

I know where you're going with the thought, but it's not applicable for this.  Why not build a filter bank, such as the amps should have for starters.  Also, the control of the back EMF in the amp is measured as it's damping.  IIRC class D amps don't have near the damping A/B does due to the output coils that are in place to smooth out all the digital noise in the first place.  

 

I think its food for thought.

The 'most ideal' way I mentioned of doing it before is patented and unavailble.

 

 

 

Who holds the patent, if I may ask?

because the market is flooded with creek pollution.

 

 

Let's go this route-  Since i'm as electrically inclined as a plumber, lol, lets see where this goes-

 

The only wire between the amp and col is the Tinsel lead and speaker wire being used.

 

Well, apparently the speaker wire never gets destroyed so we'll focus on the tinsel leads... 

 

This is a.. well, gay long shot here but lets see where it goes.. 

 

So, we destroy a sub.. we get a recone.

 

What would happen if we cut the lead between the Tinsel Lead and the coil and solder it to a rectifier diode of let's say 70A and lets say around 110-130vac.

 

If we force the current and voltage to stay in the coil at all times.. would that solve the problem?

 

Now, where the diode would be at isn't relevant right now, just the thought.

 

 

Like i say before and i think you agree too, most to all amps out there may have this problem so instead of building to what is known to manufacture but isn't, build to what's out there and common.

 

 

The problem is that you're dealing with AC voltage, the rectifier is going to do it's job filtering no matter which direction the current is coming from (whether it's a half wave or full wave rectifier, it won't matter) so you're going to rectify the output from the amp as well.

 

I know where you're going with the thought, but it's not applicable for this.  Why not build a filter bank, such as the amps should have for starters.  Also, the control of the back EMF in the amp is measured as it's damping.  IIRC class D amps don't have near the damping A/B does due to the output coils that are in place to smooth out all the digital noise in the first place.  

 

I think its food for thought.

 

I'm just glad you understand my thinking.  I like to tangle with things on a different level if possible.  DIY is so common in this hobby.  If something can be improved, i'm game.

because the market is flooded with creek pollution.

 

 

Let's go this route-  Since i'm as electrically inclined as a plumber, lol, lets see where this goes-

 

The only wire between the amp and col is the Tinsel lead and speaker wire being used.

 

Well, apparently the speaker wire never gets destroyed so we'll focus on the tinsel leads... 

 

This is a.. well, gay long shot here but lets see where it goes.. 

 

So, we destroy a sub.. we get a recone.

 

What would happen if we cut the lead between the Tinsel Lead and the coil and solder it to a rectifier diode of let's say 70A and lets say around 110-130vac.

 

If we force the current and voltage to stay in the coil at all times.. would that solve the problem?

 

Now, where the diode would be at isn't relevant right now, just the thought.

 

 

Like i say before and i think you agree too, most to all amps out there may have this problem so instead of building to what is known to manufacture but isn't, build to what's out there and common.

 

 

The problem is that you're dealing with AC voltage, the rectifier is going to do it's job filtering no matter which direction the current is coming from (whether it's a half wave or full wave rectifier, it won't matter) so you're going to rectify the output from the amp as well.

 

I know where you're going with the thought, but it's not applicable for this.  Why not build a filter bank, such as the amps should have for starters.  Also, the control of the back EMF in the amp is measured as it's damping.  IIRC class D amps don't have near the damping A/B does due to the output coils that are in place to smooth out all the digital noise in the first place.  

 

I think its food for thought.

 

Totally agree there, definitely something to roll around in my head.

 

The 'most ideal' way I mentioned of doing it before is patented and unavailble.

 

 

 

Who holds the patent, if I may ask?

 JL

Alton its AC, but as stated its when the amp starts putting out DC that problems occur.

So filter the DC if it ever arrises

I don't think that's the problem?

 

I do not think, unless extremely rare, amps simulate dc output.

 

I would assume at this point the amp would go in protect but amps generally do not go into protect unless the input stage is so out of wack it has no choice.

 

I guess i'll just slap a brand name on some order soon and start selling mono amps with lowest stable loads at 8ohms.

 

I'll rate it as follows-

 

1,800w @32ohms

3,300w @16ohms

6,000w @8ohms

 

250vAC rails baby! hehe.

Local Electrical engineering shop required for installation or warranty void, lol.

When the rectifier takes a crap the fets shoot straight dc voltage out of the output stage..

 

Makes smoke REAL quick.

Alton its AC, but as stated its when the amp starts putting out DC that problems occur.

So filter the DC if it ever arrises

What possible good is it to filter DC when the amplifier should not be producing this signal in the first place?    That's the sole reason for the damage which people just keep looking past and don't quite comprehend.  People are THINKING things, and not listening to someone who KNOWS things.

When the rectifier takes a crap the fets shoot straight dc voltage out of the output stage..

 

Makes smoke REAL quick.

i know it's possible but wouldnt the amp be shut off or in protect by that time?

 

At the very least, there would be no sound output, that's a given, but at the same time.. if the amp no longer works.. can't really blame the sub now can we,

When the rectifier takes a crap the fets shoot straight dc voltage out of the output stage..

 

Makes smoke REAL quick.

i know it's possible but wouldnt the amp be shut off or in protect by that time?

 

At the very least, there would be no sound output, that's a given, but at the same time.. if the amp no longer works.. can't really blame the sub now can we,

It would be in protect if it had that circuitry.  Then it would cost more and these $4-500 2000 watt amplifiers just don't have that.  And if they did, it would be the cheapest protection possible.  There is a reason cheap products are cheap.  Of course, there are also a lot of overpriced cheap products too.  The industry is skarred with junk.

 

When the rectifier takes a crap the fets shoot straight dc voltage out of the output stage..

 

Makes smoke REAL quick.

i know it's possible but wouldnt the amp be shut off or in protect by that time?

 

At the very least, there would be no sound output, that's a given, but at the same time.. if the amp no longer works.. can't really blame the sub now can we,

It would be in protect if it had that circuitry.  Then it would cost more and these $4-500 2000 watt amplifiers just have that.  And if they did, it would be the cheapest protection possible.  There is a reason cheap products are cheap.  Of course, there are also a lot of overpriced cheap products too.  The industry is skarred with junk.

 

 

Lmao.. you kill me sometimes.

had the amp looked at today by a local shop, no problems were found.so idk. guess im just out of a sub for now until i can pay for a recone..

Alton its AC, but as stated its when the amp starts putting out DC that problems occur.

So filter the DC if it ever arrises

What possible good is it to filter DC when the amplifier should not be producing this signal in the first place?    That's the sole reason for the damage which people just keep looking past and don't quite comprehend.  People are THINKING things, and not listening to someone who KNOWS things.

 

wasnt my idea to add a filter or maybe u weren't referring to me

 

Alton its AC, but as stated its when the amp starts putting out DC that problems occur.

So filter the DC if it ever arrises

What possible good is it to filter DC when the amplifier should not be producing this signal in the first place?    That's the sole reason for the damage which people just keep looking past and don't quite comprehend.  People are THINKING things, and not listening to someone who KNOWS things.

 

wasnt my idea to add a filter or maybe u weren't referring to me

I was referring to what you had typed which was why I quoted you. 

I say lets just go crazy....

 

Let's get Intel in this hobby and we'll use one of their Core-i5s to process protection features.. how does 32-way protection sound?  Shit.. we'll just go crazy ballistic over here.

 

Lol.. 

 

But seriously, Alton, can you elaborate on filter banks.

 

I'm trying to understand what you are saying so i need to know specifics here so i'm on the same playing field.

The filtering is typically done right at the high voltage rails with capacitors and rectification in an A/B amplifier and on the output stage in a class D IIRC. Class A/B doesn't typically present the problems with noise because its fairly easy and inexpensive to filter that signal at that point in the chain with caps and diodes or rectifiers. With class D almost all the filtering has to be done at the ouput stage because the high frequency (square wave I might add) has to go through the output fets thats modulated by the input signal. The inductors knock the edges off the digital part of the signal to make it a sine wave again. The problem there lies in the "cheap" part as high powered inductors that can filter everything as it should be are Not as cheap as caps and diodes/rectifiers. Class D amps work very very similar to a high frequency variable speed motor drive system (I think that's the right name). The difference is that instead if modulating the duty cycle with a constant variable and no need for any filtering an amplifier modulates the duty cycle with the input audio signal and filters the output for playback through a speaker.

Now, I could very very well be off on a few of these details but I think I have remembered the just of it all correctly. For a person to make their own filter bank for a class D amp it would need to consist of a very high power handling inductor with the right millihenry value to not also filter the needed audio signal. Capacitors would also be useful as the entire filter is basically just a high powered LPF in the first place.

I would never suggest anyone actually build this for use in any case by any stretch of the imagination. If you suspect a piece of equipment is malfunctioning you should have it inspected by a capable person. Or if you suspect one to be built cheap then don't buy it and save your money for something more reputable. In any case it takes more than JUST bad or cheap filtering to cause the failures as distortion, installation, program material etc. all play a part in the final signal the speaker sees. Get enough kinks in that chain and failure will be imminent, the same goes for ANYTHING audio related.

To the OP, you said you had a local shop test the amp, what exactly did they do to test it? If all the did was hook it up and listen to it play they didn't really test it. At the minimum they would have needed to put an oscilloscope on it to verify there was absolutely no DC in the output and the high frequency the amps power supply switches at is WAY above anything audible (in most cases) and even if it were in the audible range you'd never hear it because the natural inductance of a subs coils would filter it down anyway and it may not even be a high enough level to be heard over the music signal. Test equipment would be the only way to know its there and just because you can't hear it doesn't mean it can't potentially do damage.

Shizz, building a filter bank from a coil and caps would really only be useful for inquisitive testing purposes and ideally only with an amp that had known noise issues. I think the vast majority output clean enough signals that they never cause a problem. It's the rare odd case where all the wrong things happened at the wrong time for a long enough time frame to lead to this kind of failure.

The filtering is typically done right at the high voltage rails with capacitors and rectification in an A/B amplifier and on the output stage in a class D IIRC. Class A/B doesn't typically present the problems with noise because its fairly easy and inexpensive to filter that signal at that point in the chain with caps and diodes or rectifiers. With class D almost all the filtering has to be done at the ouput stage because the high frequency (square wave I might add) has to go through the output fets thats modulated by the input signal. The inductors knock the edges off the digital part of the signal to make it a sine wave again. The problem there lies in the "cheap" part as high powered inductors that can filter everything as it should be are Not as cheap as caps and diodes/rectifiers. Class D amps work very very similar to a high frequency variable speed motor drive system (I think that's the right name). The difference is that instead if modulating the duty cycle with a constant variable and no need for any filtering an amplifier modulates the duty cycle with the input audio signal and filters the output for playback through a speaker.

Now, I could very very well be off on a few of these details but I think I have remembered the just of it all correctly. For a person to make their own filter bank for a class D amp it would need to consist of a very high power handling inductor with the right millihenry value to not also filter the needed audio signal. Capacitors would also be useful as the entire filter is basically just a high powered LPF in the first place.

I would never suggest anyone actually build this for use in any case by any stretch of the imagination. If you suspect a piece of equipment is malfunctioning you should have it inspected by a capable person. Or if you suspect one to be built cheap then don't buy it and save your money for something more reputable. In any case it takes more than JUST bad or cheap filtering to cause the failures as distortion, installation, program material etc. all play a part in the final signal the speaker sees. Get enough kinks in that chain and failure will be imminent, the same goes for ANYTHING audio related.

To the OP, you said you had a local shop test the amp, what exactly did they do to test it? If all the did was hook it up and listen to it play they didn't really test it. At the minimum they would have needed to put an oscilloscope on it to verify there was absolutely no DC in the output and the high frequency the amps power supply switches at is WAY above anything audible (in most cases) and even if it were in the audible range you'd never hear it because the natural inductance of a subs coils would filter it down anyway and it may not even be a high enough level to be heard over the music signal. Test equipment would be the only way to know its there and just because you can't hear it doesn't mean it can't potentially do damage.

Shizz, building a filter bank from a coil and caps would really only be useful for inquisitive testing purposes and ideally only with an amp that had known noise issues. I think the vast majority output clean enough signals that they never cause a problem. It's the rare odd case where all the wrong things happened at the wrong time for a long enough time frame to lead to this kind of failure.

according to them they opend it up, looked for damage, checked some other stuff but said everything is perfect 

Everythibg could be perfect,but the amp could have been malfunctioning at the time of the issue.

You will not see if a rectifier has failed..they typically do not burn up anything on the board because the amplifier is still 'working'..just not throwing AC out.

 

The onlyw ay to tell is either a) hooking up a cheap speaker on it and seeing if it nukes it again, or b) look with an o-scope to see if you have any notch wave form coming out ..but it has to have a load on it to see this.

when my old amp went to dc it like sucked the woofer straight down and smoked it to all hell.. wasnt a pretty sight to see lol