Regular dynamic compression drivers can have some impedance peaks near their resonance, which are also influenced by the horn they are on.
If you use a resistor across them it can help to relieve those. Impedance compensating tuned circuits can be better. If not then the peaks can want to cause response peaks as well.
The response can be made any way you want but you'd want to simulate or measure as you go. Also since CDs don't usually start off as flat and straightforward as dome tweeters, simple crossovers will likely give less than perfect results.
If you use a resistor across them it can help to relieve those. Impedance compensating tuned circuits can be better. If not then the peaks can want to cause response peaks as well.
The response can be made any way you want but you'd want to simulate or measure as you go. Also since CDs don't usually start off as flat and straightforward as dome tweeters, simple crossovers will likely give less than perfect results.
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I am finally posting some measures. The measures were taken with two different amps just because I wanted to check the different frequency response of the Marshall 9200 compared to a solid state hifi amp.
Measures at 1m, on the speaker axis, into the listening room, at two different spl level, Behringer 8000 Mic + Behringer UM2 interface.
The SPL db absolute values are not accurate as the SPL calibration was made with an spl meter for the Smartphone.
Smoothing 1:3
Woofer RCF L18/551 , in 250 liters box, bass reflex @ 40Hz, according to original RCF project
Blu Marshall 9200 tube amp, orange SS amp.
Compression driver RCF N580+Horn RCF 6422
Blu Marshall 9200, orange SS Amp.
As I said earlier in this thread, according to RCF original project these two units should be crossed at 800hz, crossover design & specs on page 1 of this thread.
Currently I am crossing at 900Hz with an hardware active crossover, since the nearest crossover frequencies available are 720 and 900.
Would like to build a passive crossover in order to use the tube amp on the whole range, and wonder wether the original crossover design is indeed accurate or it can be improved.
Of course I can now take more measures if necessary.
Measures at 1m, on the speaker axis, into the listening room, at two different spl level, Behringer 8000 Mic + Behringer UM2 interface.
The SPL db absolute values are not accurate as the SPL calibration was made with an spl meter for the Smartphone.
Smoothing 1:3
Woofer RCF L18/551 , in 250 liters box, bass reflex @ 40Hz, according to original RCF project
Blu Marshall 9200 tube amp, orange SS amp.
Compression driver RCF N580+Horn RCF 6422
Blu Marshall 9200, orange SS Amp.
As I said earlier in this thread, according to RCF original project these two units should be crossed at 800hz, crossover design & specs on page 1 of this thread.
Currently I am crossing at 900Hz with an hardware active crossover, since the nearest crossover frequencies available are 720 and 900.
Would like to build a passive crossover in order to use the tube amp on the whole range, and wonder wether the original crossover design is indeed accurate or it can be improved.
Of course I can now take more measures if necessary.