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I was looking into the mini dsp for my first two way active plus sub setup and stumbled on this.

Auto-EQ tuning with REW | miniDSP

It looks like using the mini dsp along with the software and a mic you can have a pretty easy auto eq and do about 90% what the ms-8 does for about 2/3 the cost.

2-2x4 Mini dsp ~ $100 per unit
4 way advanced plugin ~ $10
or
2x8 mini dsp ~ $300
4x10 plugin ~$10

Behringer ECM8000 mic ~ $50
MXL Usb Mic Mate ~$50

this would give you 3 or 4 way active, auto eq, 31 band L&R graphic EQ or 6 band PEQ, T/A, active crossovers
they also have a module for a center channel if you wanted to do that as well

any one used this set up or have any thoughts?
 

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the REW is very challenging to work with and get set up.

I tried the minidsp but was disappointed with the noise it generated when the vehicle was on. the interface is nice and easy to work with, but I did not feel like going out and building a power supply to fix the noise

just my .02

let us know how it goes if you decide to take the plunge
 

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I'm using these. No noise, but I read several people have it. I think it's a ground loop or something. Also, I power it from "12V remote" from HU.

Be prepared to other issue: loud "bump" is possible at power-on - output circuitry of miniDSP contains large capacitors. You may consider buying "miniDSP Isolator" (or remove caps if your amps have them - I plan to do this).

Also, do not expect the EQ to be "auto". I'm not familiar with other EQ-ing devices, but the miniDSP-REW workflow looks like this:
- set everything up
- in minDSP: select only output(s) you do tuning
- run sweep tone in REW
- do desired EQ (you can use auto-EQ here and correct it manually)
- in order to automatically pass parameters to your miniDSP (via file export/import) you should work in "banks" - 6 PEQs at a time.

miniDSP+REW is for people who likes "tuning" and playing with setup. It's not an "auto": to modify frequency response say, of left mid I expect to spend 20mins or so.

Correct you about number of PEQ: 6 PEQ per imput/output. So for 2x4 we have 36 PEQ.
 

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Pretty cool, but looks a bit more hard-core than using an MS-8. Remember, when you do this that a single microphone measurement will not adequately represent what you hear above about 1k. My suggestion, if possible with REW is to average 3 or 4 measurements taken in the same seat--or, to use the data unsmoothed below 1k and to apply 3rd octave smoothing above 1k. Then, do the EQ and load the biquads.

This is a really cool link and a good thread. I'm going to buy a couple of these things to screw around with.

Thanks,
Andy
 

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Oh, and if you have turn on and off thumps and engine noise problems, get a DC/DC convertor that supplies the right voltage. that'll isolate the signal ground from ground and should take care of the issues.
 

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Yup.
REW supports averaging as well. I used to average 3 or more samples and then smooth to 1/3 or 1/6.

If you want to "auto-eq", then first you haver to click "set target level" several times until the "measurement graph" and "target graph" closely aligned.

Result is very good. Try it.

And as for the biquads, i think it doesn't work with 2x8 platform (96k)
The biquad is for 48k.
But no worries, we still can enter the frequency, gain and Q manually :)
 

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Yes, REW can do averages in two ways:
- number of measurement swipes (1,2,4,8) - can be done with some mic movement around interesting position
- mathematical average of two separated measurements.

But. averaging takes phase in account. And that we do not want to have at higher frequencies.
I end up making two-tree measurements and manually predict the average by starring at the screen.

Addition: There is a third way:"Average the responses" in "All SPL" window I miss before - and there is no phase calculation in it!
 

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BTW - you can use REW with the Behringers to do auto EQ as well. Not as cheap as the Minin DSP but very powerful.
 
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