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Erin,
I did the same thing in the tune I posted. Below is a snippet of my post.

Note: Sub target is above measured response. I tried upping the sub level on the output tabs of the plugin and re-measuring but the measured response level remained the same even though the sweep of the sub sounded louder which didn't make sense to me. I eventually just rolled with it and optimized anyway. The result was the sub channel gain shown in the plugin on the Dirac tab after optimization was -17db <<< yes negative gain.

So 2 things happened that don't make sense here:
1. The higher audible sweep is not plotting higher on the filter design screen.
2. Though the target is above the measured response - the algorithm is applying negative gain.

Below are some screen shots. You'll notice my targets have some nulls built in so that DLCT would not boost nulls in the midbass. Also you'll notice the sub target is above the measured response: I tried upping the level of the sub to try and meet up with the target but no matter what I did the measured response stayed the same even though I could hear the sweeps were louder which baffled me. After several attempts to correct it I just decided to roll with it and see what happens - it worked just fine and the Dirac tab is showing the sub channel level being cut 17db so not sure what is going on but it worked.

Sub:

 

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Discussion Starter #542 (Edited)
The thing
Don't shoot me if those suggestions don't help. I can give you a list of names if you want to shoot someone.
Erin have you lost your marbles.

Nobody wants to shoot anyone. If you do feel that way about a chat forum about car stereos maybe should take a break.
Furthermore, if someone feels like killing someone over a car stereo they need to be seen by a professional.

Seriously are you okay man.

I hope you were kidding.
Or joking

I’m going to think your joking ......

But if your nicely joking , I’ll be happy to Be put at the top of your list. Your oldskool. I would feel honored to be concidered one of the people you want to shoot (hypothetically) because I would die for standing up for what I believe to Be true instead of falling in step with BORING old ways that are washed up.

 

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The thing I'm concerned with here is the measured subwoofer response vs the target response below 40hz and above 60hz. Or, another way of looking at it: only 40-60hz syncs up with the target curve pre-DL filter. There's more than 10dB between those two curves below 40hz and a loooooot of delta between the two above 60hz (getting higher than 15dB at 100hz, for example).
Ian, can you check the Dirac tab in the plugin and tell us what Gain is listed on the Sub channel?
 

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Erin have you lost your marbles.

Nobody wants to shoot anyone. If you do feel that way about a chat forum about car stereos maybe should take a break.
Furthermore, if someone feels like killing someone over a car stereo they need to be seen by a professional.

Seriously are you okay man.

I hope you were kidding.
Or joking

I’m going to think your joking ......


yowza...

Ian and I know each other. So, yes, definitely kidding. ;)
 

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Erin,
I did the same thing in the tune I posted. Below is a snippet of my post.

Note: Sub target is above measured response. I tried upping the sub level on the output tabs of the plugin and re-measuring but the measured response level remained the same even though the sweep of the sub sounded louder which didn't make sense to me. I eventually just rolled with it and optimized anyway. The result was the sub channel gain shown in the plugin on the Dirac tab after optimization was -17db <<< yes negative gain.

So 2 things happened that don't make sense here:
1. The higher audible sweep is not plotting higher on the filter design screen.
2. Though the target is above the measured response - the algorithm is applying negative gain.
With as many variables as there are it’s just too hard to know for sure what’s going on. Might help to just start from the top... sorry if you’ve addressed this all before.

When you ran it, was the subwoofer designated as a subwoofer via the checkbox in the DL GUI input/output window (where you set your mic and output levels)? Or did you leave that unchecked? On the minidsp Dirac input menu do you have bass management activated (are the channels’ crossovers set to bypass or are you implementing a filter there)? Same questions for Ian.

Hopefully this weekend I can get some hands on time and sort through this stuff in tandem with y’all. I honestly feel like this process should be simpler and I really think it has more to do with us not using it as intended (as a 2-channel left/right setup) but I am absolutely down for exploring it outside of the intended use just for kicks. But maybe it’s better to start from basics and understand how to implement it that way, then move on to the more fun stuff. Scorched earth... burn it all down and start back over... that’s the only way I can save myself from me. LOL.
 

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With as many variables as there are it’s just too hard to know for sure what’s going on. Might help to just start from the top... sorry if you’ve addressed this all before.

When you ran it, was the subwoofer designated as a subwoofer via the checkbox in the DL GUI input/output window (where you set your mic and output levels)? Or did you leave that unchecked? On the minidsp Dirac input menu do you have bass management activated (are the channels’ crossovers set to bypass or are you implementing a filter there)? Same questions for Ian.

Hopefully this weekend I can get some hands on time and sort through this stuff in tandem with y’all. I honestly feel like this process should be simpler and I really think it has more to do with us not using it as intended (as a 2-channel left/right setup) but I am absolutely down for exploring it outside of the intended use just for kicks. But maybe it’s better to start from basics and understand how to implement it that way, then move on to the more fun stuff. Scorched earth... burn it all down and start back over... that’s the only way I can save myself from me. LOL.
So what I have is a 3ch Dirac setup = L, R, Sub

I did check the subwoofer box on Dirac3 (The sub channel) before testing levels and measuring.

I did not use the Bass Mgt: All filters on that tab are bypassed and all inputs are set to off feeding bass mgt. Instead I routed the L/R Sub preouts from my headunit directly into Dirac3 on the routing tab. I have all processing in the headunit bypassed (no xover, eq, or delay) and the sub level is set to max (15). Headunit is an Alpine X008U.

Just jumped in the car and took some screen shots of a few plug-in tabs:

Input & Bass Mgt. tab:




Routing Tab:




Dirac tab showing -17.7db gain on Dirac3 (Sub) channel:

 

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I actually think I’m going back to my ddrc22d and 2x4hds
I kinda miss that rabbihole of delays and all linear phase crossovers before DL
I really like the idea of only a 2 CH Dirac tune... Mostly since I only have a ddrc24, LOL....
So I would like some advise on the best way to set this up. I have a 3-way front, plus Sub. I think I need to simply have ALL left plus the L ch of the Sub on Dirac 1 and similar for the Right side. Then tune as discussed through this post, including some finer details in the below quotes... :D

I will have basic TA and XO done of course first.... Those 2 ddrc24 outputs will go to my Helix P6, but all EQ on the Helix will be bypassed. I will have the Sub XO and levels set on the P6 SUB outputs but simply passing through to the SUB AMP, right?

Oh, and would it make any difference if the pre-tune is set in the Helix OR DDRC24?

2 or 3ch DL for fronts with sub

Do your pre ta how you want.

I chose the 8ch TA numbers with excellent results, tape measure is fine also
Or do some measurements and see how they align.
Whatever , just do 2 or 3 ch DL

If have rears do 4 or 5 ch DL
2ch mode will linearize crossover phase distortion
Multichannel won’t see the phase change as it’s at the beginning and end only and it may ignore that.

So you’ll get better “phase” between all drivers on 2ch

Each Dirac channel was intended for a full spectrum stereo channel

2ch on fronts is definitely how it should be used, you could add the sub also if your GD is low and TA is clean, I did it that way for a long time.
 

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Just got done with a quick 2 (well, really 5.... Left, Right, Sub, Left Rear and Right Rear tune). Before running Dirac I took nearfield measurements and just knocked down some of the higher peaks.

The Dirac tune sounds good, but is lacking the midbass / sub bass that I had with my last manual tune. The subwoofer volume is set to -2dB, on the output tab, to not have it clip during measurements I had it set to -20dB. To get any real noticeable volume from the sub I have to bump it back up to -12dB but it then sounds like it sort of throws things off a little. I was only able to give it a really brief listen though, might tinker some more throughout the week.

Overall volume is weird as well, but I can't determine if that is me coming from the tablet and optical to a Kenwood and RCA's. Seems really quiet below about 20 (out of 40) but then at 30 gets really loud.
There is just something strange and not consistent in what Dirac is measuring and doing on its final tune on subwoofers.

1. Some positions just throw off clipping in the measurements. The manual and helpdesk just tell you to lower the sub channel in Dirac and remeasure just that position. So what does it do in that case? Do you move it back to the original position for the rest of the position?( I do this)

2. Some final tune results in that large negative Subwoofer volume. Why? No idea. It sometimes sounds ok, sometimes just too bass light. I forget to do a RTA just to see what the issue could be in those situations.

3. Some of my memory slots seems to change its subwoofer volume up a few db. Now sure how it could happen but the knob was not touched and it is under master volume mode. This happens every once in a while. Like I know it is in 0db subwoofer. then when I go do a new tune and I check the values for that same memory slot, it has moved to +3db subwoofer volume. Bug?
 

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I take it that phas is not able to be plotted(?)...
 

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Ian, can you check the Dirac tab in the plugin and tell us what Gain is listed on the Sub channel?
I'll double check it later today, but IIRC it was at -11dB on mine.


With as many variables as there are it’s just too hard to know for sure what’s going on. Might help to just start from the top... sorry if you’ve addressed this all before.

When you ran it, was the subwoofer designated as a subwoofer via the checkbox in the DL GUI input/output window (where you set your mic and output levels)? Or did you leave that unchecked? On the minidsp Dirac input menu do you have bass management activated (are the channels’ crossovers set to bypass or are you implementing a filter there)? Same questions for Ian.
Subwoofer checked in the output window, bass management activated but no crossovers there instead I have that set on the output tab. I am planning to try a couple of your suggestions later this afternoon, specifically numbers 2 and 4.

1. Some positions just throw off clipping in the measurements. The manual and helpdesk just tell you to lower the sub channel in Dirac and remeasure just that position. So what does it do in that case? Do you move it back to the original position for the rest of the position?( I do this)
That's what I have done previously, annoying, but seems to be OK.
 

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I did check the subwoofer box on Dirac3 (The sub channel) before testing levels and measuring.
Subwoofer checked in the output window


Ok. I think the quoted is key here. In short, an LFE channel is typically expected from an AVR (for home theater purposes). From an AVR these channels are boosted 10dB.

Since you checked the ‘subwoofer’ box in the DLCT menu, you’ve designated that channel as an LFE channel and thus told DL that channel will be receiving a +10dB signal from an AVR or some other ‘LFE’ channel. Now, you probably have gathered, after running some sweeps, that DL sweeps are fully internal; it’s self-generated and there is no external source for their stimulus. Case in point, if you have your radio playing in your car while you’re setting up miniDSP and then switch over to DL GUI, DL takes over and ignores the input signal so it can run the sweeps and measure the response. Since DL receives no external stimulus and depends on the user to tell it what function it serves, the LFE channel sweep is boosted by 10dB in DL because that’s what it expects to receive from an AVR; so it just accounts for that when it runs the sweeps. Then - after DL has done it’s thing and matched the response of the interally-generated sweeps to your target - when you play your stereo from the RCA outputs of your headunit (which doesn’t apply a +10dB increase for the LFE purpose) the result is the subwoofer volume being too low. Which makes sense because the measured vs target curve match looks good (at least in Ryan's case). But when you exit DL and play music off a non-LFE channel like your headunit’s subwoofer out, you’re not providing the miniDSP that extra 10dB DL was told it would have, and you have no more bass.

TLDR: Try unchecking the ‘subwoofer’ box. DL expects a +10dB boost from an LFE channel but you’re not actually giving it that from your headunit.
 

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Try unchecking the ‘subwoofer’ box. DL expects a +10dB boost from an LFE channel but you’re not actually giving it that from your headunit.
I'll make sure to give that a try later along with the other suggestions, started work not long after 5 this morning, so should be able to either grab a longer lunch break or sign off early and spend some time taking measurements.
 

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Ok. I think the quoted is key here. In short, an LFE channel is typically expected from an AVR (for home theater purposes). From an AVR these channels are boosted 10dB.

Since you checked the ‘subwoofer’ box in the DLCT menu, you’ve designated that channel as an LFE channel and thus told DL that channel will be receiving a +10dB signal from an AVR or some other ‘LFE’ channel. Now, you probably have gathered, after running some sweeps, that DL sweeps are fully internal; it’s self-generated and there is no external source for their stimulus. Case in point, if you have your radio playing in your car while you’re setting up miniDSP and then switch over to DL GUI, DL takes over and ignores the input signal so it can run the sweeps and measure the response. Since DL receives no external stimulus and depends on the user to tell it what function it serves, the LFE channel sweep is boosted by 10dB in DL because that’s what it expects to receive from an AVR; so it just accounts for that when it runs the sweeps. Then - after DL has done it’s thing and matched the response of the interally-generated sweeps to your target - when you play your stereo from the RCA outputs of your headunit (which doesn’t apply a +10dB increase for the LFE purpose) the result is the subwoofer volume being too low. Which makes sense because the measured vs target curve match looks good (at least in Ryan's case). But when you exit DL and play music off a non-LFE channel like your headunit’s subwoofer out, you’re not providing the miniDSP that extra 10dB DL was told it would have, and you have no more bass.

TLDR: Try unchecking the ‘subwoofer’ box. DL expects a +10dB boost from an LFE channel but you’re not actually giving it that from your headunit.

Erin,

I'm a manual reader before attempting type of person. Page 25 shows an illustration of where the Dirac test signal are "injected" in the signal path. This is important to me because I previously used the HU sub level control to control sub level on the fly and would tune with it at 10 (out of 15) to give some room to turn it up. But realized that would not work with the DL upgrade because the test signal does not originate from the HU. So if the test signal does not contain this lower level for the sub then had to make sure my source did not either.

This LFE angle is a good theory but not sure if it's correct... it would have to be tested. First off the this current tune that I have going is not lacking in sub-bass at all... though my first attempted tune was.

I had considered the LFE issue as being the cause of low sub output. Actually was not familiar with LFE so I did some reading to familiarize myself (I'm not a HT enthusiest)... Low Frequency Effects signal boosted by 10db.


But reading through the user manual the only mention of LFE is here on page 40:

"For a 5.1 source that applies the “10 dB LFE gain,” use 5.1 Speaker System"


So just from reading the user manual I figured LFE was not the issue as I was not choosing "5.1 Speaker System" in the Dirac app sound system tab... so therefore thinking the App was not treating the subwoofer channel as an LFE signal.

And there is no indication in the manual that corresponds LFE to the subwoofer checkbox on the Output & Levels tab. Page 42 of the manual describes the function of the subwoofer checkbox:

"The subwoofer checkbox tells the Dirac Live analysis algorithm to use a different method to detect the impulse on that channel, which in turn affects the delay that will be assigned to that channel. This is needed because of the limited frequency response of the subwoofer."


Again, just from reading the manual I don't think this is an LFE function issue - but I think it should be tested because manuals aren't always 100%.
 

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Again, just from reading the manual I don't think this is an LFE function issue - but I think it should be tested because manuals aren't always 100%.
That's why I am happy to test later, I figure anything that will help us all to get a repeatable process to getting the best results, that I think we all know are possible, with Dirac makes sense to at least try.

If it blows up something, I get to shoot Erin (or take the Mac amp) :laugh::laugh::laugh:
 

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Erin,

I'm a manual reader before attempting type of person. Page 25 shows an illustration of where the Dirac test signal are "injected" in the signal path. This is important to me because I previously used the HU sub level control to control sub level on the fly and would tune with it at 10 (out of 15) to give some room to turn it up. But realized that would not work with the DL upgrade because the test signal does not originate from the HU. So if the test signal does not contain this lower level for the sub then had to make sure my source did not either.

This LFE angle is a good theory but not sure if it's correct... it would have to be tested. First off the this current tune that I have going is not lacking in sub-bass at all... though my first attempted tune was.

I had considered the LFE issue as being the cause of low sub output. Actually was not familiar with LFE so I did some reading to familiarize myself (I'm not a HT enthusiest)... Low Frequency Effects signal boosted by 10db.


But reading through the user manual the only mention of LFE is here on page 40:

"For a 5.1 source that applies the “10 dB LFE gain,” use 5.1 Speaker System"


So just from reading the user manual I figured LFE was not the issue as I was not choosing "5.1 Speaker System" in the Dirac app sound system tab... so therefore thinking the App was not treating the subwoofer channel as an LFE signal.

And there is no indication in the manual that corresponds LFE to the subwoofer checkbox on the Output & Levels tab. Page 42 of the manual describes the function of the subwoofer checkbox:

"The subwoofer checkbox tells the Dirac Live analysis algorithm to use a different method to detect the impulse on that channel, which in turn affects the delay that will be assigned to that channel. This is needed because of the limited frequency response of the subwoofer."


Again, just from reading the manual I don't think this is an LFE function issue - but I think it should be tested because manuals aren't always 100%.

The reason I think the subwoofer check box corresponds with the LFE channel is because when subwoofer is checked I definitely heard a different stimulus. Also, I don't see what the purpose of the subwoofer check box would be if not to account for this boost, again, since DL doesn't know the source signal will or won't be boosted without you telling it; and the last thing they'd want you to do is mess with the subwoofer level after the fact. I don't have anything solid to base this on, just some "if/then" assumptions that I gave. But, it's simple enough to find out by running the setup without the sub box checked. I don't care about being right or wrong. I care about getting the most out of this thing so I'm just trying to provide some options and logic as to why I'm suggesting what I am. :)


Also, Ian, I still recommend you reconsider the subwoofer target you've used. I can't help but think that DL is trying hard to get to that and just can't do it without boosting a whole lot of frequencies. And, no, you can't have my Mc amp!!!!!! :mad::D
 

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You mean you don't have someone read to you?... You read things yourself?! You're living in the dark ages, man. You gotta get you a robot to do the reading for you. Or at least book on tape.



:D:D:D
Lol, I do live in the dark ages somewhat but I'm catching up... Just got my first smart phone this past winter :laugh: :D :p
 
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