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This is sad.
Tbh, after reading the bass control user manual and watching a couple of videos where Dirac research explains what it does - It seems to me it's just an automated way to properly set up crossover slopes & delay to ensure proper phase relationship between the subwoofer and woofer.. which most of us are familiar with all ready. Though, it would be cool for Dirac to handle crossover relationships between drivers. I'm willing to bet that in the future miniDSP will accommodate this add-on functionality... Just maybe not in the near future.
 
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Had to retune the crossovers manually and do manual EQ in minidsp. I have some big problem with midbass in the listening position due to the cabin. ( The measurement is perfect when measured nearside in the legs 60-300 very linear). But in the listening position I have a 13db peak from 180-300 Hz in the left midbass and 125-200 peak right side).

Dirac shows this problem, but it still leaves a dip between sub and midbass. So I have to solve this as much as I can first.

Anyway.
There's a new feature In Dirac live 3 called Bass Control. Anyone used it? I don't see it.
Maybe this feature will solve the lack of bass problem.
if you have peaks in that super low midrange. I'd take a look at your midbass enclosure. If its in kicks or in an enclosure. Its too small.
 

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if you have peaks in that super low midrange. I'd take a look at your midbass enclosure. If its in kicks or in an enclosure. Its too small.
It's in the doors. The measurement is great when I place the microphone in the legs, but when the mike is at the head position - that where's the problem. The same thing with the doors slightly open.
 

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It was actually the Dirac Channel Configuration. I had not changed it after changing up the Mixer channels, so it was measured "Unused" channels that were not set to "Unused". I was use to setting the channel config inside the Dirac Live program, but it's done in the CDSP program now.
 

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I don’t have a link to one like that. I know someone on here made a seat cradle out of plumbing pipe and fittings with multiple locations to put the microphone. And here’s another idea for a moving microphone stand designed by ErinH.

 

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My brain needs rest.... been reading this thread for 2 days ! On page 39 so far! Great reading here.
It was nice to meet you last weekend. Got your rca splitters sorted yet?
 
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It was nice to meet you last weekend. Got your rca splitters sorted yet?
those arrive Monday but I also traced down a bad rca wire. Replaced that and now I have the mid bass speakers running but only at half the power I wanted to give them but hey it’s progress.

been tuning by ear for days got it sounding way better... waiting on Umik to arrive as well. If I can get it to sound half as good as your car I’d be super happy!
 

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It's in the doors. The measurement is great when I place the microphone in the legs, but when the mike is at the head position - that where's the problem. The same thing with the doors slightly open.
Hey datooff! Just catching up on this thread now.

Those peaks in the frequency response you're seeing from the midbasses are likely a result of their placement in your car - namely, that they're close to or partially in your footwells. The dimensions of the footwell cavity cause those peaks and dips based on reinforcement and cancellation - constructive and destructive interference based on the wavelengths within that frequency range that interact with that cavity and alter the response as measured at ear level.

In other words, what you're measuring at your listening position vs. nearfield to the drivers themselves is normal for most car audio setups. My car exhibits a very similar frequency response in those ranges at the listening position, as do most cars. If you measure from the front passenger's seat listening position, you'll probably see that frequency response characteristic swap speakers - a big peak from 180-300Hz on the right side, and a peak from 125-200Hz on the left side.

One solution to that sort of "problem" is moving some of the sound energy elsewhere in space. That means changing your crossover points to avoid those issues by having speakers that are less proximal to the footwells play those frequencies.

My car has a savage null somewhere between 300 and 350Hz if memory serves when I have my midbass drivers playing that frequency range. So I cross them over at 280Hz. I can get away with that because I have 4" coaxial drivers covering the upper part of my response, so they can play down to 280Hz without issue, and I don't have a giant audible dip in my response as a result. Obviously that took some fabrication and cutting, but having done it, I'd never go back. Even with proper timing, you can still get a certain degree of localization cue and tell where the sound ENERGY is coming from on some tracks.

So having the vast majority of my octaves played by speakers close to shoulder and ear height vs. next to my knees makes a huge difference. I just have to adjust my curve accordingly and gradually cut the response as frequency rises in an area where most people measure flat response to sound tonally accurate...because all of that sound energy is close to reflective surfaces and my ears, so there's less attenuation from absorption than you'd see with midbasses playing higher. Hence it'd sound too bright/harsh with a typical Andy or Wisdom curve.

Tl;dr -- if you don't want to go crazy cutting into your car to put bigger drivers in the top of your doors or fabricate enclosures for your A pillars as some do, it's generally better to cut those peaks down to level and not worry about the dips as much, since they're inherently less audible than peaks. Dirac will do a lot of heavy lifting, but IMO it's generally a safer bet to cut peaks than try to boost nulls or seeming dips in response. You can ALWAYS remove energy from a response, but there's no guarantee that adding energy in a certain frequency range will get you a perceptibly or measurably louder response. It's just physics.

If you lose headroom (overall volume capability) from doing this, you can always boost your output on all channels by the same amount. I have the miniDSP boosting all channel outputs to my amps by +12dB for this reason. Clarity is pristine, and on the appropriate tracks, impact is unreal but controlled. Part of why I'm still on this thread is I want anyone reading to get to this point as well, because it makes listening to music in your car like hearing songs for the first time.

Also haven't forgotten I promised to post my response curve progress. Planning to measure for front passenger's seat optimization tonight, so I'll be sure to take screenshots of the measured response as well as post a text dump of the curve I'm tuning to now.
 

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Anyone used this for a 2-seat tune with center? If so, how are you liking it?
 

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Hey datooff! Just catching up on this thread now.
Yes, I measured the drivers from the opposite (ex. passenger side) and got reflected results. There is a dip at 400hz too.
I also tried filtering them around that 200-300hz range and it looks better on the graph, but with the tiny full ranges that can't play too low - it's not a solution. Even if the graph looks fine.
So, if in this case - big 4" midranges on the dash/pillars + crossing the midbass even lower would work well - I definitely won't do this to the existing car.
I will PEQ those peaks+Dirac and will live with it.
 
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