Yrs ago I replaced the 8" midrange speaker in my fathers XR 16's. I used a parts express speaker rated at 91.5 dB. The XR16's at rated at 89 dB. I got rid of the small little plastic backing (sealed ) thing. It appears as though the upper area of the inside of the speaker is open to the bottom of the speaker with a "slot" that runs the entire back of the speaker about 3 " wide. It is stuffed with fiber fill.
The problem is that the area covered by this 8" ( 250 -1.6kHz ) is down by about 6 dB.
Could this be because the volume of the "back chamber" for the 8" speaker should only be a small amount?
I would guess the size of the plastic part I got rid of ( yrs ago) would give the volume to be about one liter.
Thanks
Paul
The problem is that the area covered by this 8" ( 250 -1.6kHz ) is down by about 6 dB.
Could this be because the volume of the "back chamber" for the 8" speaker should only be a small amount?
I would guess the size of the plastic part I got rid of ( yrs ago) would give the volume to be about one liter.
Thanks
Paul
There is an elephant in the room here. What you describe sounds like a double chamber enclosure for your woofer. Could this be pumping your midrange driver without its smaller enclosure?
It's not clear from the information given whether what you suggest is the case. The effect of the smaller enclosure on the mid response might fall under the crossover region.
It's not clear from the information given whether what you suggest is the case. The effect of the smaller enclosure on the mid response might fall under the crossover region.
Yes, thank you. When I removed the 8" mid woofer, it was apparent that the wood separating the lower 1/3 of the speaker serving the 12" woofer and the 8" mid above it has an opening running all along the back wall about 3 inches front to back.
So, yes double chamber sounds like a correct description. The old 8" midwoofer used to be "sealed". It was a plastic thing like a deep bowl just big enough to enclose the back of the speaker.
Would removing this plastic bowl from the 8" midwoofer decrease the spl of that speaker?
So, yes double chamber sounds like a correct description. The old 8" midwoofer used to be "sealed". It was a plastic thing like a deep bowl just big enough to enclose the back of the speaker.
Would removing this plastic bowl from the 8" midwoofer decrease the spl of that speaker?
The box would increase the response at the driver's lower end. It hasn't been made clear in what band the midrange driver is being used, so that's still a maybe.
Also, the pumping might be running the coil out of the gap. Just a guess. Not sure that would come up in a sweep style measurement.