Alright so i bought this subwoofer from parts express, a mass diy audio distributer. I bought this sub with a 12" passive radiator, 4 6.5" full range boss audio speakers, a 1000RMS watt amp, and an 800RMS watt amp. I have the Ultimax 10" on the 1000RMS watt amplifier. Heres the specs of the subwoofer:
Resonant Frequency (Fs)26.9
HzDC Resistance (Re)3.2 ohms
Voice Coil Inductance (Le)1.28
mHMechanical Q (Qms)3.08
Electromagnetic Q (Qes)0.59
Total Q (Qts)0.49
Compliance Equivalent Volume (Vas)0.83 ft.³
Mechanical Compliance of Suspension (Cms)0.15 mm/N
BL Product (BL)14.5
TmDiaphragm Mass Inc.
Airload (Mms)227g
Maximum Linear Excursion (Xmax)19
mmSurface Area of Cone (Sd)327.8 cm²
This subwoofer, when pushed only a small amount, causes a quite loud mechanical noise. The spider is not coming loose. I made sure to do plenty of research on this sub before purchasing, and I have seen people throw 7k watts when the sub itself is 500wrms. I have watched multiple videos showing ranges of 800-7k watts being pumped into this thing and it's excursion reaching the base of the mounting holes (extremely far). I dont know what is causing this mechanical noise, I have tried several different amps ranging from 200 watts, to 1000 watts. I'm debating sending this subwoofer back to the manufacturer, but I'm afraid of having the same problem occur with the next one. Please somebody help.
Subwoofer:
https://www.parts-express.com/dayton-audio-um10-22-10-ultimax-dvc-subwoofer-2-ohms-per-coil--295-510
Resonant Frequency (Fs)26.9
HzDC Resistance (Re)3.2 ohms
Voice Coil Inductance (Le)1.28
mHMechanical Q (Qms)3.08
Electromagnetic Q (Qes)0.59
Total Q (Qts)0.49
Compliance Equivalent Volume (Vas)0.83 ft.³
Mechanical Compliance of Suspension (Cms)0.15 mm/N
BL Product (BL)14.5
TmDiaphragm Mass Inc.
Airload (Mms)227g
Maximum Linear Excursion (Xmax)19
mmSurface Area of Cone (Sd)327.8 cm²
This subwoofer, when pushed only a small amount, causes a quite loud mechanical noise. The spider is not coming loose. I made sure to do plenty of research on this sub before purchasing, and I have seen people throw 7k watts when the sub itself is 500wrms. I have watched multiple videos showing ranges of 800-7k watts being pumped into this thing and it's excursion reaching the base of the mounting holes (extremely far). I dont know what is causing this mechanical noise, I have tried several different amps ranging from 200 watts, to 1000 watts. I'm debating sending this subwoofer back to the manufacturer, but I'm afraid of having the same problem occur with the next one. Please somebody help.
Subwoofer:
https://www.parts-express.com/dayton-audio-um10-22-10-ultimax-dvc-subwoofer-2-ohms-per-coil--295-510
Is the 10" Ultimax mounted in a box? It's quite easy to push a driver to its excursion limits if it is just sitting there in the open and not in a closed box.
Is the cone moving much when you hear the noise? Xmax is I think something like 19mm one way, but I don't know how far past that the VC former will hit the back plate. That will make a tapping noise. Is that what you hear?
It's certainly possible that the particular driver that you have there is defective in some way. PE has a good return policy. Explain the situation and allow them to make it right if you do find some kind of performance problem. I suggest you do more checking first.
Is the cone moving much when you hear the noise? Xmax is I think something like 19mm one way, but I don't know how far past that the VC former will hit the back plate. That will make a tapping noise. Is that what you hear?
It's certainly possible that the particular driver that you have there is defective in some way. PE has a good return policy. Explain the situation and allow them to make it right if you do find some kind of performance problem. I suggest you do more checking first.
Yes, call them. Explain the situation and how you were running it.
Does it smell smoky? If not, it's not thermal overload.
Does it rub when pushed by your hand? If not, it's not a misalignment of the pole or voice coil.
Was it in a box? If not, it should be when running that kind of power.
How well was the driver sealed or mounted to the box? Air-leaks can cause frame rattling against the box.
Vented or sealed box? You'll find that the Ultimax drivers will work better in a sealed box volume. Unloading below tuning can cause bottoming where the former will tap the backplate.
7kW? No- I don't think so. 500W RMS is more appropriate on the UM10. I am using it in a bandpass with a 500W plate amp and +6dB of boost at 25Hz, and about 50% gain is still making it move pretty far.
I'm guessing you either have it in a PR-bass-reflex box, or have built my Overdrive10 design for your car. If it's a straight PR BR, then could it be the PR making the noise? How low did you tune the PR? Too high of a tuning will allow unloading easily of both units. If the PR unloads, it can buckle and flex, causing a metallic sound. My bet is either PR buckle or UM10 bottoming.
It could very likely be your implementation, and not the drivers' faults at all.
Later,
Wolf
Does it smell smoky? If not, it's not thermal overload.
Does it rub when pushed by your hand? If not, it's not a misalignment of the pole or voice coil.
Was it in a box? If not, it should be when running that kind of power.
How well was the driver sealed or mounted to the box? Air-leaks can cause frame rattling against the box.
Vented or sealed box? You'll find that the Ultimax drivers will work better in a sealed box volume. Unloading below tuning can cause bottoming where the former will tap the backplate.
7kW? No- I don't think so. 500W RMS is more appropriate on the UM10. I am using it in a bandpass with a 500W plate amp and +6dB of boost at 25Hz, and about 50% gain is still making it move pretty far.
I'm guessing you either have it in a PR-bass-reflex box, or have built my Overdrive10 design for your car. If it's a straight PR BR, then could it be the PR making the noise? How low did you tune the PR? Too high of a tuning will allow unloading easily of both units. If the PR unloads, it can buckle and flex, causing a metallic sound. My bet is either PR buckle or UM10 bottoming.
It could very likely be your implementation, and not the drivers' faults at all.
Later,
Wolf
I agree with Wolf on the 7kW claim. You put a real 7kW into that driver and you better have your marshmallows ready.
The ultimax 10 has dual spiders, so the lower spider that is not visible might be compromised. Send Parts Express and email and they will take care of you if the speaker is under the warranty period. BTW, the YouTube video claiming 7kW is questionable without voltage/amperage metering. Maybe 2kW it could withstand for a few seconds. It probably lasted as long as it did because at those levels of excursion, there was a lot of airflow being pumped in and out of the motor, but at some point it just won't be enough for a 2.5" coil.
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I had the same issue with a 12" Ultimax
I returned it and ordered a replacement which also had the same issue (sent that one back too just today)
It is a mechanical noise even at very low levels
Really strange
Here is the recording: Shared album - Peter Pataki - Google Photos
I am considering ordering a totally different driver
I returned it and ordered a replacement which also had the same issue (sent that one back too just today)
It is a mechanical noise even at very low levels
Really strange
Here is the recording: Shared album - Peter Pataki - Google Photos
I am considering ordering a totally different driver
Misalignment voicecoil from factory, have same issue with my 15" from new. but i playing hell out of it anyway... have no issues yet.
