sr6500 tweeter fuse

[bizza]

So well, I finally installed these. They are great, I love them.
They are in fully deadened doors, getting 50 x 2 rms from an Aura 4200 4 ch amp.
Now, when I play them a bit loud (about 25 out of 35 on my Alpine HU, depending on the song), the crossovers light up like christmas trees. Not only am I concerned about the crossovers and the tweets, but it is annoying driving at night and having my underseats light up to the rythm of the music lol...

Any idea wtf is up here?? I didnt spend $600+ on a pair of components that can't handle 50 rms......

[Greg Peters]

Is there a chance your gains are set too high and you've run the amp into clipping (hence the tweeter protection engaging)? Or maybe your amp is underrated? Not familiar with the amp.

I'm running more than that to a pair of SR5250s, and the bulbs in the tweeter protection circuit don't light up at the volumes I listen at. I've yet to have tweeter output diminish (a sign the protection circuit is engaging) even at the highest volume levels I've played them at.

[Thom]

The bulb is there to protect the tweeters so if they're lighting up they're doing the job. I've got a Zapco amp in my car running 100 watts x 4, and two of those channels drive SR5250 crossovers and my bulbs don't light up unless I'm really beating the **** out of the system.

I asked our engineer about it and he said: "The bulb responds to RMS current. More current makes them heat up and glow, which raises their resistance and limits the current that can get to the tweeters. When they're cold, they're basically shorts so there's no limiting, but once they pass a certain level of current they heat up quickly and clamp the current flow. So, if he is clipping the amps they're spraying distortion into the circuit which raises the RMS level and could cause the bulbs to glow more readily than a clean amp at the same SPL."


An Alpine head unit that goes up to 35 max volume should have clean output up to 32 or so. So the loudest you ever listen should be at 32, and the gains could be backed down so that you're not clipping at that point. With only 50 watts a channel you might not reach a desired output before clipping, so if a slight gain adjustment doesn't work you'll need a bigger amp.

[MacLeod]

Agreed.

Im running the 5250's and Im bi-amping them so each tweeter is getting 50 watts and each mid is getting 50 watts and they can handle it no problem.

[bizza]

Is there a chance your gains are set too high and you've run the amp into clipping (hence the tweeter protection engaging)? Or maybe your amp is underrated? Not familiar with the amp.

I'm running more than that to a pair of SR5250s, and the bulbs in the tweeter protection circuit don't light up at the volumes I listen at. I've yet to have tweeter output diminish (a sign the protection circuit is engaging) even at the highest volume levels I've played them at.

gains on the amp are set at around 2pm on the gain knob (maybe 75%).

Right now I'm not using the other 2 channels on my amp. Eventually, I could bridge this amp to provide 150 x 2 rms to the components, but if they can't even handle 50 rms, dont want to smoke them to pieces with 150 rms....

[bizza]

The bulb is there to protect the tweeters so if they're lighting up they're doing the job. I've got a Zapco amp in my car running 100 watts x 4, and two of those channels drive SR5250 crossovers and my bulbs don't light up unless I'm really beating the **** out of the system.

I asked our engineer about it and he said: "The bulb responds to RMS current. More current makes them heat up and glow, which raises their resistance and limits the current that can get to the tweeters. When they're cold, they're basically shorts so there's no limiting, but once they pass a certain level of current they heat up quickly and clamp the current flow. So, if he is clipping the amps they're spraying distortion into the circuit which raises the RMS level and could cause the bulbs to glow more readily than a clean amp at the same SPL."


An Alpine head unit that goes up to 35 max volume should have clean output up to 32 or so. So the loudest you ever listen should be at 32, and the gains could be backed down so that you're not clipping at that point. With only 50 watts a channel you might not reach a desired output before clipping, so if a slight gain adjustment doesn't work you'll need a bigger amp.

Well I am fine with the protection doing its job, however it was my understanding that these could handle at least 100 RMS...

Now, that is interesting about the clipping. Could clipping in a 50 rms channel do this for the SR6500s?? Would you say that I could safely bridge the channels on my amp to give them 150 rms, and maybe this could let me listen at the same volume level without those lights flashing???

[bizza]

Agreed.

Im running the 5250's and Im bi-amping them so each tweeter is getting 50 watts and each mid is getting 50 watts and they can handle it no problem.

ok I'm starting to think that maybe my amp isn't clean enough, and it is clipping.

Are you able to crank up your SR5250s without the lights flashing??

Another thing: at this volumes, where the bulbs light up, I get plenty of background noise. Is this a sign of clipping???

[Greg Peters]

When a signal fed to your speakers is clipped, you'll get a harsh, distorted signal and some background noise along with it. The normally smooth sine waves found in the signal become chopped at the top and bottom, and the resulting signal is distorted- your amp will put out more than it's rated power when driven into clipping, so if that's the case your speakers are seeing much more than 50 watts RMS.

http://www.resnet.trinity.edu/areynol1/gain.htm

http://www.bcae1.com/

I wouldn't be surprised if you are trying to get more volume out of your amp than it's designed for. The SR5250s and SR6500s are definitely capable of handling their continuous rated power specifications, so you'll want to turn your gain down...if the resulting volume level with 50 watts isn't sufficient, you might want to consider upgrading the amp to something putting out the 125 watts RMS your SR6500s are rated at (the 5250s are rated lower, at 100 watts RMS) to get the volume level you desire without clipping.

[bizza]

When a signal fed to your speakers is clipped, you'll get a harsh, distorted signal and some background noise along with it. The normally smooth sine waves found in the signal become chopped at the top and bottom, and the resulting signal is distorted- your amp will put out more than it's rated power when driven into clipping, so if that's the case your speakers are seeing much more than 50 watts RMS.

http://www.resnet.trinity.edu/areynol1/gain.htm

http://www.bcae1.com/

I wouldn't be surprised if you are trying to get more volume out of your amp than it's designed for. The SR5250s and SR6500s are definitely capable of handling their continuous rated power specifications, so you'll want to turn your gain down...if the resulting volume level with 50 watts isn't sufficient, you might want to consider upgrading the amp to something putting out the 125 watts RMS your SR6500s are rated at (the 5250s are rated lower, at 100 watts RMS) to get the volume level you desire without clipping.

That's an excellent answer. I just spent the last hour reading up on setting up gains, I thought it was kindof a volume control or something... had no clue that it is used to match the HU with the amp...

This makes so much sense, I was obviously driving my amp into clipping, as I tried to get more volume.

Many thanks to everyone for the help. I'll go ahead and bridge the channels in my amp to feed the components with 150 x 2 rms, and hopefully that should resolve the issues. I'll report back when I'm done!

btw, I'll see if I can catch a video of those bulbs lighting up for the last time! You could easily believe that I installed custom leds under the seats that light up to the rythm of the music, pretty neat lol...

[MacLeod]

Beat me to it.

Setting the gains at 2:00 is way too high. Thom was right and you were clipping your amps and sending out not only a very distorted signal but also one at about 125 watts. Remember, when you clip an amp the signals output is limited only by its input voltage so itll send out a whopper of a powerful signal.

Youre on the right track now tho.

[audiobliss]

I want new speakers. :(