In this case its Kartesian drivers, they have many driver models with Imped. stated very precisely, like 4.9Ohms, 6.3, 5.5 etc.
Other brands mostly say its either 4, 8 or 16 ohms.
So now I wonder, should I round it to nearest 4 or 8? or just beware not to mix too WIDELY different impedance drivers?
The other similar question i have: what is the maximum tolerable difference in drivers Sensitivity within one single speaker?
For example, when one is 86dB (high midrange) and woofers are 96dB - is it too big gap?
I see some commercial models which mix 87dB woofers with 93dB AMT tweeters.....
Other brands mostly say its either 4, 8 or 16 ohms.
So now I wonder, should I round it to nearest 4 or 8? or just beware not to mix too WIDELY different impedance drivers?
The other similar question i have: what is the maximum tolerable difference in drivers Sensitivity within one single speaker?
For example, when one is 86dB (high midrange) and woofers are 96dB - is it too big gap?
I see some commercial models which mix 87dB woofers with 93dB AMT tweeters.....
Kartesian gives the Re (Direct Current Resistance) of their drivers, as well as an impedance curve for the driver. As an example, the Wib100vPA-S driver's Re is 5.6 ohms, the free-air impedance ranges from about 80 ohms at Fs (free-air resonance) to around 7 ohms at 500 Hz, then rises to around 35 ohms at 10,000Hz.
When all the driver parameters are provided, no need to round them. Most drivers have widely different impedance with frequency, requiring specific passive crossover designs to accommodate them.
Attenuating (reducing) the upper range speakers to match a woofer is no problem, but choosing a mid or high speaker of less sensitivity would require throwing away lots of low frequency power in a passive system, -10 dB would drop 10 watts down to a 1 watt level.