Measured by Dr Boar: Beyma CP21/F - diyAudio
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Old 12th August 2015, 09:02 PM   #1
DrBoar is offline DrBoar  Sweden
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Default Measured by Dr Boar: Beyma CP21/F

I have a pair of old second hand CP21/F Beymas graphs looks like this (linked in Europe Audio)

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The new shiny one and the corresponding graph from Beymas home page.

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My own measurements:
Using XTZ room analyzer II. Driver on carpet facing up with mic 10 cm in front of driver.
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Using Omnimic with 1 m measurements distance and the driver at the end of a long spirit level so there is no baffle loading. The setup:

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The results using both a 5 dB and 2 dB resolution.

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I think my measurements using both different systems and setups are consistent with the Beyma graphs.
The shelf 2-4 kHz is there, as is the peak around 8 kHz and the squiggle at about 13 kHz and finally the drop just below 20 kHz.

I intend to do distortion (105 & 95 dB perhaps) and time domain measurements. But I need to get better earplugs to protect my hearing and also do the measurements when my wife is out of the house.

Regarding my measurements there is consistent dip below 4 kHz compared to Beymas measurements. Do the horn actually benefit from a baffle? Not that I intend to cross it lower than 4 kHz.
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