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Erin, Thanks for taking the time to provide us this detailed write up :thumbsup:

I have a few questions:

This gets me to #3: Equalizing the driver response. Now, to be honest, one should also take the time to pre-measure each active driver’s response and then use broad strokes to flatten out any large peaks or anomalies seen. However, I didn’t do this my first go-round because, frankly, I was too giddy at the thought of this new toy and I went straight to Step #4.... ...
With all of this in mind, you can understand why MiniDSP encourages us to pre-correct the response of the "speaker" before we run DL, especially when used in the car environment.
It's unclear, to me, if you ever went back and did some broad stroke driver correction?



Step #4: Set up my crossovers for each speaker driver... A portion of Step #4 includes setting time delay....
Did you go as far as to align acoustic xovers up, at the listening position, so as to minimize phase issues in the xover regions?

Did you adjust levels and apply xovers so as to maintain a flat response from 20-20khz or to loosely follow the target curve you had in mind?

Also, when running the Dirac channel per driver measurement in order to obtain the delays - Were all the xover filters engaged?



Here's the same screenshot but of only the DL targeted - modified Wisdom curve (orange) and the optimized response (green):

Would be interesting to see the actual measured response and how it aligns with the theoretical "optimized" response. Did you happen to take any after measurements?
 

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Discussion Starter #7
Erin, Thanks for taking the time to provide us this detailed write up :thumbsup:
Thanks, Ryan. :)


It's unclear, to me, if you ever went back and did some broad stroke driver correction?

Did you go as far as to align acoustic xovers up, at the listening position, so as to minimize phase issues in the xover regions?

Did you adjust levels and apply xovers so as to maintain a flat response from 20-20khz or to loosely follow the target curve you had in mind?

Also, when running the Dirac channel per driver measurement in order to obtain the delays - Were all the xover filters engaged?

Would be interesting to see the actual measured response and how it aligns with the theoretical "optimized" response. Did you happen to take any after measurements?


I did not. But I'm glad you asked. I meant to bring that back up again in my final assessment, particularly because I did little to optimize the response before DL had it's turn. What I did do was set crossovers on my compression drivers so that the horn loading effect was flattened out, and I did add a broad filter on my midranges around 800hz (a shelf would have been more effective but I just didn't do that), and I set my T/A based on DL's result of each active speaker. I failed to mention this I believe but I also used DL's gain adjustment values from the active driver sweeps to set the levels before I re-ran DL in 2-channel stereo mode. I'll need to update my OP to add this info.

But, overall, I did little before I ran DL. I think that speaks even more to the benefit of DL's capabilties based on the results I got.

I also should have mentioned this in the review, because I did mention it in another thread, that it would make more sense to me to not work to flatten the response too much in areas where you plan to have a curve that already mimics the natural response. For example, if you have a high frequency response that is falling, and you plan to have a target curve that is doing roughly the same, I wouldn't try to pre-correct the signal to flat; I think that would just be wasting time and DSP resources. But that's just a suggestion.



Would be interesting to see the actual measured response and how it aligns with the theoretical "optimized" response. Did you happen to take any after measurements?

I did this really early on but didn't think to grab screenshots. The response I measured was practically perfectly matched to what DL targeted and resulted in. The higher frequencies didn't match as well but that's more a function of me using a single mic measurement when I re-measured again. I think most of us know that it's imperative to take an average of measurements over an area because even moving the mic one-quarter of an inch can alter the measured the response. This same question came up in a thread on one of the home audio forums, though, and the folks who replied with data showed that DL's corrected response was indeed what it said it was. So, I wouldn't personally spend time trying to verify if DL actually did what the software says it did. Just my $0.02.
 

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... and I set my T/A based on DL's result of each active speaker.
So this means that all xovers were applied when measuring in multichannel Dirac to obtain the time delays?


I failed to mention this I believe but I also used DL's gain adjustment values from the active driver sweeps to set the levels before I re-ran DL in 2-channel stereo mode. I'll need to update my OP to add this info.
Good info but triggers another question: What target curves did you use when optimizing the multichannel Dirac setup? Just the auto-targets for each driver or something else?... I would assume this would have an effect on the levels it calculates which were used in your final 2ch Dirac config?
 

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So this means that all xovers were applied when measuring in multichannel Dirac to obtain the time delay?
Yes.





Good info but triggers another question: What target curves did you use when optimizing the multichannel Dirac setup? Just the auto-targets for each driver or something else?... I would assume this would have an effect on the levels it calculates which were used in your final 2ch Dirac config?
Oh, goodness. I honestly don't remember. This was done on the same night I was trying all sorts of things (like matching my manual tune curve, and recording the response of the different tunes with binaural mics). I *think* I was using the manual tune curve, though. I checked the DL delay values and the deltas between drivers were in family with what I had already achieved by ear. So no crazy values that one might go "oh, that's to account for the crossover delay", just in case you were wondering. Speed of sound doesn't care about crossovers. It's frequency independent. It's the same regardless of the bandwidth. Phase rotation, however, is a different story.
 

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Excellent write-up Erin... appreciate your time and information.

I am sure it would be super helpful to a LOT of people to have a step by step guide on using this system from beginning to end... particular on how to setup the routing and mixing tabs.

1. Do this
2. Do this
3. Do this
etc., etc.

The manual is mind-boggling to me... way more info than is needed and let direct to the point instructions on how it is to be setup. I realize there are a lot of options, but similar to what you suggested... most people buying this product are doing a 2 or 3-way active front with a subwoofer somewhere behind them... and maybe rear fill.
 

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great write up. Much appreciated. I always wanted there to be a great auto eq option like this.

As of what I tried (pioneer auto-eq, JBL ms8, Alpine Audessey) the kicker key had the only auto eq results that didnt require major tweaking but its a low power amp. Super impressive and Id like this option on their larger amps. This is wayyy more flexible and tweak able.

To be clear the unit is $500, then to be able to use DL will cost about $400 more. So roughly $900 to give it a go.

I am very intrigued about using this with a 2 way in front and rears + sub.

Is there surround sound processing of some sort or any effects for rears in this unit?
 

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great write up. Much appreciated. I always wanted there to be a great auto eq option like this.



As of what I tried (pioneer auto-eq, JBL ms8, Alpine Audessey) the kicker key had the only auto eq results that didnt require major tweaking but its a low power amp. Super impressive and Id like this option on their larger amps. This is wayyy more flexible and tweak able.



To be clear the unit is $500, then to be able to use DL will cost about $400 more. So roughly $900 to give it a go.



I am very intrigued about using this with a 2 way in front and rears + sub.



Is there surround sound processing of some sort or any effects for rears in this unit?
The unit plus software is 900. I think the umik comes with it and you have to use the Umik-1 mic with it.

There's no upmixing for center or 7.1 or anything like that but it does have the ability to do rearfill.

I promise. Its worth every dime.


Sent from my XT1710-02 using Tapatalk
 

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EXCELLENT write up. It answered a bunch of the questions that were bouncing around in my head regarding tuning with this device/software.

Now I just need to decide if my next purchase will be new tweets/ mids or the 8x12DL :)
 

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I have been reading the posts on here and the MiniDSP forums about the live units... and have wondered about getting the 24hd version and using it along with my helix mini dsp, I have a apl1 now which I have had since 2015 and don’t think I have used it to its full potential. Would it be worth it it, as in not using the xover, time alignment part of the MiniDSP running it after the head unit into the helix just for the eq ?
 

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I have been reading the posts on here and the MiniDSP forums about the live units... and have wondered about getting the 24hd version and using it along with my helix mini dsp, I have a apl1 now which I have had since 2015 and don’t think I have used it to its full potential. Would it be worth it it, as in not using the xover, time alignment part of the MiniDSP running it after the head unit into the helix just for the eq ?
Are you asking if you should buy a 2x4HD and put it inline before the Helix? Or are you asking if you should buy a CDSP 8x12DL and put it inline before the Helix? Regardless, the answer is no to both.

If you have an APL and Helix Mini then you basically have the same functionality as the unit that is reveiwed above albeit less channels of Dirac and an additional AD/DA conversion.
 

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tl;dr :p






Excellent write-up, thanks for your time and effort. Did I understand correctly that after buying the unit, you have to pay extra for the Dirac Live?
 

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tl;dr :p

Excellent write-up, thanks for your time and effort. Did I understand correctly that after buying the unit, you have to pay extra for the Dirac Live?
You can buy the 8x12 or the 8x12-DL straight from MiniDSP. If you have or buy the 8x12, you can pay for the Dirac upgrade.
 

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Are you asking if you should buy a 2x4HD and put it inline before the Helix? Or are you asking if you should buy a CDSP 8x12DL and put it inline before the Helix? Regardless, the answer is no to both.

If you have an APL and Helix Mini then you basically have the same functionality as the unit that is reveiwed above albeit less channels of Dirac and an additional AD/DA conversion.
APl is a group delay removal device and a linear phase crossover (in the 1012) Not quite a automated room correction. Although with the right hands behind a APl it could do similar but it’s overall sound is quite different.



I’m using linear phase crossovers and have removed all my group delay by use of FIR banks in rephase before I use my Dirac live. Linear phase definitely is something to take a serious look at and is a massive improvement, otoh what Dirac live does is more related to the room and not the speakers. Dirac does a magnificent job at opening up the soundstage and creating a depth of sound parallel to none by making the transfer functions (IRs) match on left and right.
Linear phase does nothing to make them match, it removes the group delay caused by crossovers and enclosures.


I have been reading the posts on here and the MiniDSP forums about the live units... and have wondered about getting the 24hd version and using it along with my helix mini dsp, I have a apl1 now which I have had since 2015 and don’t think I have used it to its full potential. Would it be worth it it, as in not using the xover, time alignment part of the MiniDSP running it after the head unit into the helix just for the eq ?


If you want Dirac live and want to keep a helix

I would look at the ddrc22d

Keep it digital all the way to helix is ideal

If your source is analog than the ddrc24 (the 2x4hd version of Dirac) would work

Right now I’m using 3x 2x4hds and a ddrc22d upstream with excellent results
The 2x4hds as a DAC and fir crossover / linearization tool and Dirac as my eq
 
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