Hi Earl
I only took the measurment 20 degree of axis at 2m. Apologies. I ran a small test with the changed crossover frequencues earlier, and it is definitely a step in the right direction. For some reason, the output to the LF when testing, was much softer than the HF. Seem to have sorted that out now though. Difficult to set when you running multiple amps of varying output power.
I only took the measurment 20 degree of axis at 2m. Apologies. I ran a small test with the changed crossover frequencues earlier, and it is definitely a step in the right direction. For some reason, the output to the LF when testing, was much softer than the HF. Seem to have sorted that out now though. Difficult to set when you running multiple amps of varying output power.
Hi Brendan, gating is a technique of choosing how much of an impulse width that software is recording, is to be used in calculating FR. The longer the time window, the more of room response and lower in bass we see the response. Minimum phase is just a convenient phase data for a simulation so it does not have to be calculated separately.
Were you latest measurements with or without mini dsp filters on?
I don't work with REW, I can only simulate crossover filter in a passive version and once finished, present the curves that you could use as template to do the same with mini dsp. This is the reason of asking the measured curves to be the raw drivers only, without any kind of signal conditioning. The same voltage drive on paralleled woofers and the same on tweeter.
Were you latest measurements with or without mini dsp filters on?
I don't work with REW, I can only simulate crossover filter in a passive version and once finished, present the curves that you could use as template to do the same with mini dsp. This is the reason of asking the measured curves to be the raw drivers only, without any kind of signal conditioning. The same voltage drive on paralleled woofers and the same on tweeter.
I am reading text file "LF 1m on-axis".
1000 Hz= 81.7 dB
2000 Hz=62.9 dB
gives 18.8 dB/octave, which acts as a 3rd order acoustical LP filter employed.
This is a low passed response, and I need it free of any kind, as it looks on manufacturer graph in infinite baffle.
May be I am misunderstanding. How does one activate a crossover (order, frequency) in mini dsp?
1000 Hz= 81.7 dB
2000 Hz=62.9 dB
gives 18.8 dB/octave, which acts as a 3rd order acoustical LP filter employed.
This is a low passed response, and I need it free of any kind, as it looks on manufacturer graph in infinite baffle.
May be I am misunderstanding. How does one activate a crossover (order, frequency) in mini dsp?
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No, I'd leave that aside for now. Active filtering as in mini dsp, is supposed to be a huge help for a designer that enables one to create all kinds of filters in a matter of minutes. We should be able to come up with some kind of a decent active filter pretty fast. In your place I would let the mic rest in a position, 1 m or 2 m away and get the summing at a crossover point to be flat and observe what happens when you change polarity on tweeter. Good phase matching in crossover region creates a suckout of FR. 20 dB of vertical division in REW is a bit too large, try 10 dB.
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I'll let Lojzek speak for himself ( as he has ) but typically ( for passive network design ) one wants "RAW" transducer curves to work from for all drivers ( ie; no additional filtering added what-so-ever ).
The JBL compression driver is very robust and won't get hurt it at all by specifying a sweep frequency in REW that starts at 300hz ( with a level of something like 85db at the test mic ).
You do realize applying any crossover point ( LP or HP ) results in the application of a filter ( by definition of what a filter is ) .
Don't worry about raw response. Just deal with the filter settings and measure along. Get the tweeter response flat all the way to 10 kHz and elevate the whole range with amplifier or wherever you get to do this in mini dsp. Tweeter is closer to the mic so it should be delayed by some amount, may be 2", 3" in equivalent ms sound flight. By the evening this has to sing like Pavarotti, lol.
Brendan, that info is in post 90 ( 300hz @ 85db at 1M at the mic ).
I realize that you're now getting pulled in 2 directions > so I'll stand back & let you concentrate on giving Lojzek what he wants.
Realistically I already have what I need ( including a ZMA file for a 2425/6H on a 2342 horn ).
Therefore, I can publish curves & a network design at anytime > but I'll hold-off until I see your ZMA files posted here.
Neither am I, but if the equipment is there already, why not..
I don't know what the better listening angle would be but I'd be inclined not to guess to use 0 degrees. On the other hand, if using 0 degrees for the crossover design alone gives a slight downward tilt to the top end overall, then it might work out.
I don't know what the better listening angle would be but I'd be inclined not to guess to use 0 degrees. On the other hand, if using 0 degrees for the crossover design alone gives a slight downward tilt to the top end overall, then it might work out.
Hi guys. So saw your posts(lozjek and Allen). My listening position is approx 45 degrees off axis directly in the centre of The speakers. I have been playing around and fine tuning the setup. I have taken the multimeter and matched the outputs on the amps. Jig for impedance measuring will be finished tomorrow as well. So all on track for accurate measurements Saturday morning. I have now worked out how to export correction filters from rew and import them onto the minidsp as well. My only problem, is I don’t quite understand the “fields” for the target settings in the rew eq section. Once I do all the measurements on Saturday morning, I will post them for all to look at, and we should be able to do some corrective work on rew to import onto the minidsp and get it sounding very good. Thanks for all the help and support so far
Post 14, 20 Feb included:
Ima say it again: The OP is not building a passive system, and is struggling with lots of new info.
So, in the context of a minidsp 4x10, perhaps you chaps can suggest which bits of advice you've previously given, that the OP could ignore / put aside for later?
e.g. the impedance measuring jig doesn't seem useful for an active build, so this task doesn't seem like a good use of time & brainpower:
If he did want to measure impedance, I'd suggest wasting less time by just buying this.
Dayton Audio DATS V2 Computer Based Audio Component Test System
Because: learning curve. A dude who is not poor (14 staff) is probably better off spending $100 rather than putting together an item he doesn't know much about.
Ima say it again: The OP is not building a passive system, and is struggling with lots of new info.
So, in the context of a minidsp 4x10, perhaps you chaps can suggest which bits of advice you've previously given, that the OP could ignore / put aside for later?
e.g. the impedance measuring jig doesn't seem useful for an active build, so this task doesn't seem like a good use of time & brainpower:
If he did want to measure impedance, I'd suggest wasting less time by just buying this.
Dayton Audio DATS V2 Computer Based Audio Component Test System
Because: learning curve. A dude who is not poor (14 staff) is probably better off spending $100 rather than putting together an item he doesn't know much about.
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