Measuring using REW and Umik mic.
Thats a good question, the speakers are sounding very good after a few mods but this “anomaly” in the response has me down a rabbit hole……
Thats a good question, the speakers are sounding very good after a few mods but this “anomaly” in the response has me down a rabbit hole……
Here we go:
The speaker is stood on a table in the middle of the room so that the mid and tweeter are rough at half the height of the room. The mic is around 1m away, sweep from 1khz - 20khz, level checked before the sweeps at 80db. One is pointed at the mid, one is pointed at the tweeter and one between the two, shown with 1/6 smoothing:
The speaker is stood on a table in the middle of the room so that the mid and tweeter are rough at half the height of the room. The mic is around 1m away, sweep from 1khz - 20khz, level checked before the sweeps at 80db. One is pointed at the mid, one is pointed at the tweeter and one between the two, shown with 1/6 smoothing:
I've tried to have a play with impulse response but I'm not sure what this tells me.
This is an overlayed response of the tweeter and midrange measured at around 2"
These are the impulse responses.
Tweeter at 2":
Midrage at 2":
This is an overlayed response of the tweeter and midrange measured at around 2"
These are the impulse responses.
Tweeter at 2":
Midrage at 2":
I'm assuming that with the speaker off the floor, in the middle of the room and with the mic so close to the driver this will cut-out the room reflections, so everything up to 3ms is pure driver and box?
Sorry for the multiple post, I'm just sharing my musings in the hope that it will reveal some hidden truth that I cannot see......
Sorry for the multiple post, I'm just sharing my musings in the hope that it will reveal some hidden truth that I cannot see......
The drivers are 1.5-2m-ish from all walls, floor and ceiling.
for this measurement, how far from the drivers should the mic be?
for this measurement, how far from the drivers should the mic be?
Great. Can you do one with only the mid and one with only the tweeter. Leave the mic in the same spot for both.
The tweeter is a Pioneer D66AP45 51F, I can't find any specs for this but I know its an 8 ohm driver.
I note that the peak in SPL at just over 5 kHz shown on the midrange's data sheet corresponds to the one shown in your frequency response curve.
Yes, so the driver is behaving as it should. I’m assuming at this point that its not the original driver given that these are 80’s speakers and from what I can tell the Visaton is a 90’s onwards production.
Yes, it can't be the original midrange driver.
Midrange driver beneath tweeter. Click to expand.
Midrange driver beneath tweeter. Click to expand.
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Yes, definitely different..... so I assume tweaks to the crossover are needed or maybe back to the L Pad idea just to attenuate both the mid and tweeter?
There's no harm in experimenting with L pads but, since you say the speakers are "sounding very good", need you go to all the trouble?
A speaker with a perfectly flat response can be made, but be considered as unexciting by many listeners.
That's why there are so many different speakers out there, all with their own peculiar deviations from a flat response built in to suit different consumer tastes.
A speaker with a perfectly flat response can be made, but be considered as unexciting by many listeners.
That's why there are so many different speakers out there, all with their own peculiar deviations from a flat response built in to suit different consumer tastes.