Need some bass help!

Yesterday while tuning I noticed that if I leaned forward in my seat, that the bass got substantially louder. Thinking it was my sub I decided to play an 80Hz test tone and tinker around with the time alignment to see if I could pull it back more towards the listening position. However, with all the speakers but the sub muted, the bass from the sub appears plenty loud enough in the drivers seat.

So, I decided to check the midbass. Right only, sounds fine, plenty loud. However, with just the left midbass playing it sounds as if it is coming from my passenger footwell (along with a rattling grill which I will have to fix) and I have to lean forward to really hear it. So, my issue might actually be with the left midbass. I flipped the phase in the DSP which made no noticeable difference. I measured and use the tracerite website to get time alignment values. Overall everything sounds good, wide and up on the dash. Just the bass in the drivers seat is lacking unless leaned forward about 20".

Any suggestions? I am debating trying to source a mic and using REW, but hoping to at least get on the right track without it.

Thanks.

I'd be curious about angle of midbass driver

This ^^^ and do you have a pretty tall center console?

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Originally Posted by Hic

I'd be curious about angle of midbass driver

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The midbass are in the doors, firing straight out. Not the easiest to see in this picture below, but if you look where the door pocket ends you can just make out the speaker grill (D shaped piece). Not that I think it matters with this, but tweeters are in stock locations at the top of the door and midrange are in the kick panels.

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Originally Posted by chithead

This ^^^ and do you have a pretty tall center console?

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Depends on what you call tall? I would say it is reasonably tall, you can get a good idea from the pic (not my vehicle, but identical).

http://i204.photobucket.com/albums/b...yah/7A_640.jpg

Hmmm... my only suggestion would be to revisit the time alignment again. Do you remember the suggested delays from the Tracerite website? There is a tab on there for crossover settings. I know it says experimental, but without using that feature, midbass was very lacking, and kind of, "wonky" sounding in my car. But after using the crossover tab, it recommended a much further delay, and definitely helped fix the midbass issue I was fighting too.

The suggested delays that it gave me are:

LT - 1.97
RT - 0.73
LMR - 0.8
RMR - 0
LMB - 1.17
RMB - 0.15
SUB - 0.04

I put in values on the crossover tab (not sure if I am correct on the values I entered without looking on the DSP, but I know I am in the ballpark) and it definitely gives me much further delays:

LT - 0.99
RT - 0
LMR - 1.17
RMR - 0.07
LMB - 3
RMB - 1.46
SUB - 16.56

Going to give those a shot likely tomorrow evening once I confirm my crossover settings, will be interesting to hear the difference. Hopefully I can get this figured out, the overall sound is good, but leaning forward in the seat it just sounds that bit better. Gets a bit uncomfortable driving like that though!! haha

angle ain't gonna change nothing at 80 cycles.

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Originally Posted by chithead

But after using the crossover tab, it recommended a much further delay, and definitely helped fix the midbass issue I was fighting too.

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Well, gave this a shot and while I could only put in the half cycle for my sub delay (BitOne does not let me put in a 15ms delay), it did improve the bass in the drivers seat a good bit........... however, I seem to have lost some of the upper range now instead. At least I think I can pull those back by bumping the EQ some once I figure out what to bump up, going to try to play around with it some more later. At least I remembered to save my earlier set up first incase I need to revert back to it!!

Decided to leave my tweeter and mid delays where I had them based on distance, but used the tracerite values for crossovers on the midbass and the sub. This seems to be a little better, so getting closer, may need to drive around for a bit and listen to some music to know for sure. I get the feeling at this point I may be reaching the limits of my ability at tuning this.

I'm glad there's an experimental crossover tweak on the tracerite site. What you got is making sense in comparison to where mine ended up after Steve did the tape measurer method, then had me add a little (and in some cases a lot) more delay to the left side. Trust your ears, but it's always nice to have a well trained set of ears in there too to get the general idea roughed in.

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Originally Posted by Hillbilly SQ

I'm glad there's an experimental crossover tweak on the tracerite site. What you got is making sense in comparison to where mine ended up after Steve did the tape measurer method, then had me add a little (and in some cases a lot) more delay to the left side. Trust your ears, but it's always nice to have a well trained set of ears in there too to get the general idea roughed in.

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Yep, the tracerite site has been pretty helpful! I definitely need to spend some more time with things, but as you said it's nice to get a well trained set of ears to point you in the right direction!!

After driving around a bit with the latest setup, there are other issues now, a lot of the stage to me sounds as though it is much louder on the right, vocals don't seem to stay in one spot but drift left depending on the frequency. I matched left/right levels using my phone and the Dayton iMM-6 microphone playing pink noise. I flipped the phase on my midbass at the amp (versus just in the DSP) and it made no difference. I did discover that the left midbass is quiet in the drivers seat, the right quiet in the passengers seat. So, I think they are both playing fine just some kind of cancellation happening on the seat I am sitting in.

Not entirely sure what direction to go in now, I think I am going to try to find someone reasonably local who is more experienced at tuning than I am, along with seeing if I can borrow a USB microphone from someone to try using REW. Might also go ahead and reset all the settings on the DSP and start fresh.

If you have around $80 to spend the umm6 is a great tool to have at your disposal any time you need it. I just got done with my first tune with the use of an rta and it was a big success. Just hop in with a fully charged battery on the lappy and put a "do not disturb" sign on your car. Kyle Ragsdale has some great tuning tutorials on YouTube. I got each pair playing as close to identical to each other as possible and worried about the tonality curve later. It's a lot of work and a lot like doing surgery but it's worth it in the end. There's a lot that your ears aren't able to pick up on without measurement equipment unless they're highly trained. You'll be shocked at just how messed up each side is without a lot of surgical l/r eq.

Been watching Kyle's videos for a while now, very very helpful!! I will likely pick up a UMM6 at some point. For now seeing how far I can get with AudioTool and a Dayton iMM-6. Looks like the hardest piece with it is comparing Left and Right speakers, it is possible, just not as easy as with REW/RTA. Here is how things currently look:

This is taken with my phone running AudioTool at ear height, a big dip around 500Hz and a spike around 8000Hz:

Attachment 5472

This on the other hand was taken with my Nexus 7, mounted in the dash, also running AudioTool. The curve looks good other than the spike around 700Hz. Obviously though since this is not at ear height, it's pretty much useless. Just kind of funny to show the difference between ear height and where the "head unit" is mounted:

Attachment 5471

Going to measure with my phone again either later today or tomorrow to try and figure out the dip and what is causing it, along with knocking down the peak at 8KHz. The dip is a little below where my midbass/midrange crossover is set. 99% certain all the speakers are in phase.

Slowly making improvements, I essentially saved what I had and then restarted following along with the steps on Kyle's videos as best I can with the equipment I have available to me. Vocals still wander left on higher frequencies, but it is getting there. Now if only work did not get in the way I could go spend some more time on it....

Yup, that reading at ear height looks about right for something that's uncorrected. A vehicle cabin is a TERRIBLE room for listening to music:laugh:You're tuning mostly for the room in a vehicle as you probably already know.

Sorting out the 8KHz peak should be fairly simple, it's the dip that I am not sure about without resorting to boosting those frequencies.

Boosting is something you do and learn to work around the issues it can cause but don't tell anyone what you did. Just leave enough room for that boost to do its thing without clipping. It can be your dirty little secret;)

Check and see if that floating voice moves with volume. If it does then it may very well be a reflection issue.

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Originally Posted by Zippy

Check and see if that floating voice moves with volume. If it does then it may very well be a reflection issue.

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Worth a check! I suspect that it does move with volume, sometimes I can be listening to something and it sound fine. I can then listen later at a different volume and it sound off.

Have a Dayton UMM-6 microphone on the way, so I can at least start working with REW. I think I could get close with AudioTool and the iMM-6 I already have. But, the scale in the app coupled with the small size of my phone screen makes it a little tough. Just wish Amazon would get on and ship it, hoping it will be here by Friday since I will have some time after work to spend on it.

If you do discover that it does indead change location with volume, then no amount of EQ will fix it. You need to adjust the aiming of the speakers producing that frequency.

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Originally Posted by Zippy

You need to adjust the aiming of the speakers producing that frequency.

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Hopefully that does not turn out to be the case, no real way to adjust the aim of my speakers since they are in stock locations. The mid's are in the kick panels and may have some slight adjustment available, but for the most part the locations are pretty fixed.

Dayton mic arrived Saturday, I had hoped to start taking some measurements earlier today but my laptop decided it needed to do a giant update which took well over an hour. Finally got that done, plugged in the BitOne and the software told me a dll file was missing and so it would not start. Removed and re-installed the drivers, finally got the software started. Plugged in the microphone, removed all the crossover settings from the speakers, started REW, tried a sweep and got an error of "Very low signal detected on measured" so at that point I said screw it and quit for the day. Gonna see if I can find some time Wednesday to start again!

Figured a quick update would be worth while, been slowly getting my head around using REW and am currently working with this:

http://i305.photobucket.com/albums/n...pseze8cskx.jpg

From what had started as this:

http://i305.photobucket.com/albums/n...psx9ykb8mj.jpg

In fact it probably looked a little worse than that initially!! I used HolmImpulse to help get time alignment dialed in, then been using REW. Still needs some more fine tuning, specifically the left midbass dip of 150Hz, but it sounds pretty good right now.

isn't that mid bass dip on one side, pretty normal though?

Like, if you try and fix it with boost, it just gets out of hand before you smooth it out, like it's a reflection, or mode, or node, or null, haha...

and flipping polarity of the one side just improves imaging, at the expense of mid bass response in that small region. Or, it's probable that anything done to "fix" that graph, ends up being at the expense of sound quality.

I mean, it looks pretty darn good... except for what's happening at 470-500 hz, maybe that could use some lift.

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Originally Posted by cajunner

isn't that mid bass dip on one side, pretty normal though?

Like, if you try and fix it with boost, it just gets out of hand before you smooth it out, like it's a reflection, or mode, or node, or null, haha...

and flipping polarity of the one side just improves imaging, at the expense of mid bass response in that small region. Or, it's probable that , anything done to "fix" that graph, ends up being at the expense of sound quality.

I mean, it looks pretty darn good... except for what's happening at 470-500 hz, maybe that could use some lift.

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Your thoughts mirror mine, I get the feeling that I could spend who knows how long trying to sort that one little piece out and in the meantime it give me other issues. I do in fact already have it boosted about 4dB anyway, with it still almost 10dB down. I think I know what is causing the 475-500Hz issue and that should be very easy to fix... in fact, heading to car now to see about fixing that.

The midbass are in the entryways, terminating straight out. Not the most effortless to find in this photo underneath, yet in the event that you look where the entryway take closes you can simply make out the speaker flame broil (D formed piece). Not that I think it is important with this, but rather tweeters are in stock areas at the highest point of the entryway and midrange are in the kick boards.