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Blown drivers in Danley SM60F
leon garrity:
Well my luck gets better,
this weekend ive managed to blow 3 horns in total,all burnt to a crisp???????
can anyone shed any light,im using a Lab fp 3400 on the SM60f
now i know it says the Danleys can take 800 cont/1600 program.I try never to get the amp to clip but it delivers 1500 at 4ohms,but it delivers 94 volts max output can this be too much for the Danley box .When i ran the EAW,i had to implement the max voltage into the eaw processor and it would automatically set the limiters to protect the drivers. Since using the Sm60f's i have gone through 8 horns,if i set the amp to give me only 1000 watts the box doesn't get as loud.
The SM60f can give out upto 127db max now what does it need to generate that,if i were to give it only 800 watts i definatley wouldnt get a workable volume.
Could this be any of the following???????
voltage spikes
too much voltage from amp to drivers
too much wattage to box from amp,but if i put smaller amp on it does not go as loud.
Why only the horns?????????? not the whole box if it was too much power then surely the mid driver would go bang with 1500 watts on it.
can different amps work better with different boxes?
any advice would be good.
Ivan Beaver:
leon garrity wrote on Sun, 06 February 2011 21:15
Well my luck gets better,
this weekend ive managed to blow 3 horns in total,all burnt to a crisp???????
can anyone shed any light,im using a Lab fp 3400 on the SM60f
now i know it says the Danleys can take 800 cont/1600 program.I try never to get the amp to clip but it delivers 1500 at 4ohms,but it delivers 94 volts max output can this be too much for the Danley box .When i ran the EAW,i had to implement the max voltage into the eaw processor and it would automatically set the limiters to protect the drivers. Since using the Sm60f's i have gone through 8 horns,if i set the amp to give me only 1000 watts the box doesn't get as loud.
The SM60f can give out upto 127db max now what does it need to generate that,if i were to give it only 800 watts i definatley wouldnt get a workable volume.
Could this be any of the following???????
voltage spikes
too much voltage from amp to drivers
too much wattage to box from amp,but if i put smaller amp on it does not go as loud.
Why only the horns?????????? not the whole box if it was too much power then surely the mid driver would go bang with 1500 watts on it.
can different amps work better with different boxes?
any advice would be good.
It is not only the wattage "available" from the amplifier, but rather the amount of signal applied over time.
If you are running compressed material (highly likely) then you are actually delivering more "average" power over time.
Also the balance of the high freq to the mids and lows could be excessive. Some people like a shrilling top end-which will add to the power that is delivered to the horns. Of course I have no idea how your "alignment" or musical content actually sounds.
Power ratings are based on "normal" standards which are produced to as best as possible simulate normal music. Non "normal" content can put stresses on certain elements that would not normally be there.
There are limits to how loud any box can get.
Ivan Beaver:
leon garrity wrote on Sun, 06 February 2011 21:15
Well my luck gets better,
this weekend ive managed to blow 3 horns in total,all burnt to a crisp???????
can anyone shed any light,im using a Lab fp 3400 on the SM60f
now i know it says the Danleys can take 800 cont/1600 program.I try never to get the amp to clip but it delivers 1500 at 4ohms,but it delivers 94 volts max output can this be too much for the Danley box .When i ran the EAW,i had to implement the max voltage into the eaw processor and it would automatically set the limiters to protect the drivers. Since using the Sm60f's i have gone through 8 horns,if i set the amp to give me only 1000 watts the box doesn't get as loud.
The SM60f can give out upto 127db max now what does it need to generate that,if i were to give it only 800 watts i definatley wouldnt get a workable volume.
Could this be any of the following???????
voltage spikes
too much voltage from amp to drivers
too much wattage to box from amp,but if i put smaller amp on it does not go as loud.
Why only the horns?????????? not the whole box if it was too much power then surely the mid driver would go bang with 1500 watts on it.
can different amps work better with different boxes?
any advice would be good.
Some more thoughts.
Apparently you have gone through quite a number of HF diaphragms.
Are you SURE-absolutly sure) that you do not have any HF oscillations in your system. Now you will NOT hear them-often they are ultrasonic 9above hearing range).
I know of several cases that VHF oscillations cause constant HF driver damage. One case was at 60Khz, another at 45Khz, another at 30Khz and another at 25KHz.
This is not very common, but DOES happen. I know of only those 4 cases in all my years in this business.
The only way to check is to put an O'scope on the amp outputs, with everything hooked up as normal-but with no input. But of course one of the inputs could be causing the problem.
Have you been cleaning out the cap real good after a failure? If not this could contribute to an early death of the next one.
Also have you examined the crossover? Does anything look like it has gotten hot? resistors with discolored letters/cracks/light brown spots in the middle-capacitors with cracked cases-coils with melted bobbins or dark windings and so forth.
It is possible that the crossover got damaged some time ago and is not having the correct freq to to the HF drivers and putting strain on it.
Anytime there is damage to one part of a circuit in any device (loudspeaker-amplifier etc) you have to look at other areas that are associated with it to make sure they are operating normally.
Jeff Bailie:
Just a guess, but I bet that crappy sound card you had damaged your new speakers over time.
From the very beginning of your posts on the SM60's I suspected a compression/signal issue.
I think you have been feeding those SM60's a bad signal for too long.
You know what happens when you eat an unhealthy diet every day? You age quicker and die young...
When you get them fixed, I would suggest throwing away your computer.
I don't think you can blame the SM60's in any way after all of your posts pertaining to signal problems.
I would buy some new drivers, and then I would not hook up the same broken computer to test them.
Tim Padrick:
I've been told of instances where amps oscillated when playing, but were fine when idling. One instance was cured when the speaker cable was removed from metal conduit and hung from same by tie line.
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