I am new to measurements and I'm a little overwhelmed with the different types of measurements and need some guidance. I have installed REW, I have an external sound card, condenser omnidirectional measurement mic, I followed the steps in the REW help section, calibrated the sound card,made all the necesary connections and took my first measurements of a bi-amped 12 inch+1.4 inch top using this type of measurement:
https://imgur.com/a/qkbq2" rel="nofollow - https://imgur.com/a/qkbq2
Each driver at a time and then the two playing together.
The whole measurement setup was: ECM 999 superlux mic on a stand 1 meter from the loudspeaker aimed at the acoustic center, connected to a Steinberg UR22 on input 1, from output 2 on the UR22 I made a loop and fed it to channel two,from channel one output I sent signal to one channel on a DBX Driverack pa2 , from that to the High out and to HF amp in and from mid out to MF amp in.
Made the necesary level calibrations using pink noise and the level meters in REW ,clicked on measure and voila, i got a graph. I have seen the peaks on the HF section and corected them with the PEQ in the DBX, and measured and PEQ and measure getting it as flat as I could. Same thing with the mid section, that had a surprisingly fast roll off after 200 hz,probabily some cancelation due to the position or to much fonoabsorbant in the box,lowering tuning and LF efficiency ( just an asumption, please correct me if I'm wrong.)
I have not done any gain staging between the DSP and amps, no limmiters set, just the xover point that I chose @ 1,5 Khz on both drivers with a 24 dB BW slope.(I made this decision due to the fact that the HF voicecoil is 2.5 inches( HF144 Faital) and the Beyma TD385 horn I'm using probabily sound bad lower becouse it is a 230mm x 230 mm 1.4 inch exit horn, again an asumption ,don't know if I'm right or wrong due to very little experience in X-overs.And I set the level using the input attenuators on the amps for the HF to match the woofer in SPL on the measurement graph.
When I listened to a few tracks the sound got much better then before, but still needs work.
Questions are, is the type of measurement that I have made a measurement of the initial sound coming from the speaker without room intereference, or I have measured the speaker and room all together?
When I time and phase align , should I use delay , until the phases overlap as mush as possible@x over point?
What type of measurement do I have to use for this initial setting of the speaker(phaseing,setting levels and xover point, and what type of measurement should I use when I want to see the frequency response of the room I'm trying to tune the whole system in. I know in theory what I have to do, but I don't understand how I should measure it.
The system I'm trying to tune consists of 2 x MTL46 loaded with FaitalPro 18HP1010(4 ohm) , 2 x reflex tops using FaitalPro 12PR310 ,FairalPro HF144 and a Beyma TD385 Horn.
Amps are, Mach Audio MA900 , 2 x 240W@ 8 ohms on the HF , Mach Audio MA1300 , 2 x 350 W@ 8 ohms on the MF, and Ecler DPA2000, 2 x 940 W @ 4 ohms on the LF.
I know that subs will always have to be align, depending on positioning from tops.
Some help would be grately apreciated, also point me to some books that i could read to better understand what I need to do.
Have a great day!
P.S. Sorry for the long post.
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