Justin Zazzi's tuning companion for room eq wizard

If I set Linkwitz 24 DB 80 HZ high pass on the spreadsheet for my woofer in a 2way setup, does it matter if in my dsp I actually have to set a Buttwerworth 36 db at 100hz to hit the target curve? Is it just phase I would have to worry about then? Thanks !
 
If I set Linkwitz 24 DB 80 HZ high pass on the spreadsheet for my woofer in a 2way setup, does it matter if in my dsp I actually have to set a Buttwerworth 36 db at 100hz to hit the target curve? Is it just phase I would have to worry about then? Thanks !

Electrical settings do not matter. It is only if you hit the acoustical curve, so you did exactly what you should be doing. Don't change a thing :)
 
To get the near the 80 80 acoustic crossover for my sub and mid bass, in my dsp I have had to set mid woofers to 100 LW and my 2 small 6.5 boxed subs (Helix MATCH PP 7E-D) to 60 LW. Is this right or do you think something wrong with my setup somewhere? Seems like a big electrical gap. Also this small sub has a MASSIVE peak at 50 hZ and takes a lot of cutting to get down to the target line and I do feel like a have lost a too much bass at the moment so might turn it back up in that area a tad. Sounding good though
 
To get the near the 80 80 acoustic crossover for my sub and mid bass, in my dsp I have had to set mid woofers to 100 LW and my 2 small 6.5 boxed subs (Helix MATCH PP 7E-D) to 60 LW. Is this right or do you think something wrong with my setup somewhere? Seems like a big electrical gap. Also this small sub has a MASSIVE peak at 50 hZ and takes a lot of cutting to get down to the target line and I do feel like a have lost a too much bass at the moment so might turn it back up in that area a tad. Sounding good though

you are good if it matches the acoustical curve. My electrical settings are all over the place in my car and home theatre.
 
Just in case people with virtual channels want to try this dip from the jazzi curve, I did 3.1khz, Q=1 and -3db from a flat tuned Sq preset which made it very much more pleasant when I give it some death :) thanks Justin!
 
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My question would be, if it's an overlap electrically, or acoustically?
If electrically, it doesn't really matter if the acoustical targets are met.
F.e. with my current setup i overlap my midrange and tweeters quite a bit, but acoustically they meet the target lines.
 
Yes the formulas will work, like Jdunk says.

However your results might be strange.

I am also curious why you prefer to over/underlap the frequencies. What are you hoping to accomplish?
 
My midbass capable of playing down to 40hz. I find it sounds more pleasant overlap the midbass and sub. Also more of authentic sub upfront sound.
 
REW Settings?

Sorry if this has been documented somewhere - if so, please just send me the link. Here's what I am trying to do and my questions:

* Tweeter 24db LW from 3000 on up
* Midrange 24db LW 300 to 3000
* Midbass 24db LW 80 to 300
* Sub 24db LW up to 80
* using Jazzi'sTarget curve

1) RTA settings - 1/3 or 1/6 octave,smoothing, anything else?
2) EQ settings -
a. Equalizer - I'm guessing Generic - I'm using a Mosconi DSP.
b. Target type - I think I saw "None" was recommeneded - is that correct?
c. Based upon Target type, any other settings that need changing?
4) Filter tasks - what's the recommendation for the Match Range? Boost options? Flatness curve? Let's take my midrange (300-3000 LW) for example.

Thanks,
Dave
 
With this technique:
-single microphone, either USB or XLR
-moving spatial average (wave microphone around by hand)
-at listening position (near driver's headrest)
-playing noise from REW or the wav file it produces

I like to use these settings on the generator:
-noise
-periodic pink noise
-full range
-sequence length 16k
-level -12dBFS RMS

Then (and only then) you can use these settings on the RTA window:
-mode 1/48th octave
-smoothing none
-fft length 16k (match the generator!)
-averages forever, while you wave the mic around
-window rectangular (only works for periodic noise if sequence and FFT lengths both match)
-max overlap 0%

To take a measurement:
-play noise in a loop either from REW's generator or the wav file it can create
-turn on the RTA by pressing the red record button
-wave microphone around the listening position slowly
-press the "reset averaging" button on the RTA window
-continue waving microphone around the listening postion
-wait until the RTA trace settles and stops changing a lot
(this is usually 10-20 averages or more)
-press the red record button to stop the RTA
-stop playing the noise
-on RTA screen, press save "current" trace

Finally, apply the smoothing you want:
-on the main REW screen, go to the "all traces" tab
-select all of the traces you've measured above
-open settings by pressing the gear icon
-change smoothing to 1/3rd-octave
-press apply smoothing
(experiment with other smoothing if you wish, I like 1/3rd or 1/6th sometimes)



View attachment 18089


View attachment 18088
 
When you want to use the EQ window, try this. Load the house curve for the overall shape that you want to use. My spreadsheet will create a file that is named "REW_Curve_something_overall.txt". Use that one in the REW house curve selection.

Then go to the EQ page within REW and try these settings:
-target settings
-target type, speaker driver
-crossover HP cutoff (Hz), 80
-crossover HP type, LR4
-crossover LP cutoff (HZ), 300
-crossover LP type, LR4

This should create a target for your midbass speakers. Then adjust the highpass and lowpass type and frequency to adjust the target for your subwoofer and your dash speakers. This is a very similar process to using the individual text files that the spreadsheet creates, but it takes a little less clicking. Thanks to jdunkl and others who helped discover this trick.

I cannot help you much with the auto eq settings like filter tasks, match range, max boost, etc. I do not use the auto feature and don't have much intuition with what settings work well. I strongly encourage you to try creating filters yourself, if you are comfortable trying it. Just keep the Q values around 0.5 to 3.0 and you'll avoid chasing your tail too much.


View attachment 18090
 
When you want to use the EQ window, try this. Load the house curve for the overall shape that you want to use. My spreadsheet will create a file that is named "REW_Curve_something_overall.txt". Use that one in the REW house curve selection.

Then go to the EQ page within REW and try these settings:
-target settings
-target type, speaker driver
-crossover HP cutoff (Hz), 80
-crossover HP type, LR4
-crossover LP cutoff (HZ), 300
-crossover LP type, LR4

This should create a target for your midbass speakers. Then adjust the highpass and lowpass type and frequency to adjust the target for your subwoofer and your dash speakers. This is a very similar process to using the individual text files that the spreadsheet creates, but it takes a little less clicking. Thanks to jdunkl and others who helped discover this trick.

I cannot help you much with the auto eq settings like filter tasks, match range, max boost, etc. I do not use the auto feature and don't have much intuition with what settings work well. I strongly encourage you to try creating filters yourself, if you are comfortable trying it. Just keep the Q values around 0.5 to 3.0 and you'll avoid chasing your tail too much.


View attachment 18090

I really do love that feature in REW. SO glad they added it. Saves a lot of files being generated and then having to constantly change the house curve each time you change what driver or where you want crossovers placed.
 
Finally, apply the smoothing you want:
-on the main REW screen, go to the "all traces" tab
-select all of the traces you've measured above
-open settings by pressing the gear icon
-change smoothing to 1/3rd-octave
-press apply smoothing
(experiment with other smoothing if you wish, I like 1/3rd or 1/6th sometimes)
Two items:

1) The above part of your post is the part I don't understand. I don't see an "all traces" tab on my main REW screen??

2) You didn't mention it, but I'm guessing that you do the left and right channels separately? And the sub as well?

Thanks,
Dave
 
Two items:

1) The above part of your post is the part I don't understand. I don't see an "all traces" tab on my main REW screen??

2) You didn't mention it, but I'm guessing that you do the left and right channels separately? And the sub as well?

Thanks,
Dave

Oops, I meant to say "All SPL". See screenshot below.

I like to do one channel at a time for all the frequency response steps. By unique, I mean basically once for each RCA cable or once for each DSP output channel. Sometimes this is once per actual speaker, or once per quadrant if you have a passive crossover 2-way in the front left, etc.



View attachment 18119
 
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