DiyMobileAudio.com Car Stereo Forum banner

201 - 220 of 726 Posts

·
Registered
Joined
·
950 Posts
Discussion Starter #201
I managed to get her fired up over the weekend. Not without some sort of issue of course.

I still have the factory rear doors, center, and d-pillar surround speakers still playing through the factory amp. All other speakers were un hooked and sent to DSP for signal. Once I verified the amps and DSP and all were working, I cut the wires, at the amp, of the left d-pillar speaker and the whole left side stopped playing. Hooked wires back.... Music came back. Same for right side. Wtf? Do they have the entire side run in some sort of series? Or does the factory amp need to have a load on every channel in order for it to work?

I remember reading on ramforum about guys having to use resistors but I didn't have an issue at the time so never paid attention to why they needed them.

Next is that I cannot get it to image. Stage is all over the place and un-focused. I think having a crossover in the oem amp then being crossed over again in the DSP is causing some phase issues? Once I get just the tweeters and TMs playing, I'll address this issue.

But, it seems to have plenty of potential from
What I'm hearing now. Lots of detail and plenty of volume. Shit is much louder than I expected. But I'm glad I planned on running 3 way. 2 way just seems to be lacking for me. Maybe my mind would change after a proper tune and all but... Ya know
 

·
Registered
Joined
·
950 Posts
Discussion Starter #203
Did you cut the wires after the amp? I've heard that disconnected wires before the amp will shutdown the audio signal but not after.

Pretty sure it was after the amp, but now that u mention it Idunno. There is only 2 plugs on the amp both right next to each other so im not sure what's actually going in vs coming out.
 

·
Registered
Joined
·
356 Posts
Pretty sure it was after the amp, but now that u mention it Idunno. There is only 2 plugs on the amp both right next to each other so im not sure what's actually going in vs coming out.
I also plan to disconnect everything that is not running to the DSP so that is interesting to say the least. I thought that the harness for the input wires included a power and ground wire? That would tell you which is which, if so. Haven't looked at the one in my Durango but thought that was the case.
 

·
Registered
Joined
·
950 Posts
Discussion Starter #205
I also plan to disconnect everything that is not running to the DSP so that is interesting to say the least. I thought that the harness for the input wires included a power and ground wire? That would tell you which is which, if so. Haven't looked at the one in my Durango but thought that was the case.

I jut went out and disconnected the wires from the rear pillar and center channel and everything is still working. Maybe I did originally cut the wrong wires?

Either way, eliminating those 3 speakers made a huge difference. Imaging is still off tho. I should have a few hours tomorrow to put the RTA on it and see what's going on.
 

·
Registered
Joined
·
950 Posts
Discussion Starter #206
This morning I played a bunch of test tones, and noticed they're scattered all over the place. 3150hz actually sounded like it was outside the passenger window. Then I played an out of phase pink noise on Sheffield lab disk and everything (just about) centered up on the dash. Actually right outside the window on the hood. Deepest I ever heard before.... So id say I'm having phase issues but I dunno how to go about solving them...

I guess I could start with switching polarity of one speaker at a time?

When I first got it playing I played with the phase adjustments in the DSP but didn't notice any diference. I'll try again

I read in Andy Whemeyers tuning guide about crossovers and phase shifts (still way over my head), but I gathered that 12db slopes cause a 90 degree shift. Not sure what the stock amp is set at but the DSP is at 24db LR. I'm wondering if the signal being crossed over in the oem amp then again in the DSP is causing the issues? I'll mess with these too.


Any other suggestions? I got a free night again so Ima undo the rear speakers and deaden the doors them whip out the mic and see what's going on.
 

·
Registered
Joined
·
7,202 Posts
This morning I played a bunch of test tones, and noticed they're scattered all over the place. 3150hz actually sounded like it was outside the passenger window. Then I played an out of phase pink noise on Sheffield lab disk and everything (just about) centered up on the dash. Actually right outside the window on the hood. Deepest I ever heard before.... So id say I'm having phase issues but I dunno how to go about solving them...

I guess I could start with switching polarity of one speaker at a time?

When I first got it playing I played with the phase adjustments in the DSP but didn't notice any diference. I'll try again

I read in Andy Whemeyers tuning guide about crossovers and phase shifts (still way over my head), but I gathered that 12db slopes cause a 90 degree shift. Not sure what the stock amp is set at but the DSP is at 24db LR. I'm wondering if the signal being crossed over in the oem amp then again in the DSP is causing the issues? I'll mess with these too.


Any other suggestions? I got a free night again so Ima undo the rear speakers and deaden the doors them whip out the mic and see what's going on.
12dB/oct crossover (2nd order) should be 180 degrees, that's why we flip one of the speakers (I usually do the tweeters) if you're making a passive crossover and running the speakers close together. That way there's less of a problem at the crossover point between the two speakers.

edit: it should be a 90 degree phase shift per order.

edit (reading) http://audiophilereview.com/reference-speakers/crossovers-are-evil.html
http://www.prosoundweb.com/article/print/crossovers_the_series_an_introduction_to_the_basics


So if you're using 24 or 48dB/octave crossover points, you should have 360 or 720 degree shifts.
 

·
Registered
Joined
·
950 Posts
Discussion Starter #208
12dB/oct crossover (2nd order) should be 180 degrees, that's why we flip one of the speakers (I usually do the tweeters) if you're making a passive crossover and running the speakers close together. That way there's less of a problem at the crossover point between the two speakers.

edit: it should be a 90 degree phase shift per order.

edit (reading) http://audiophilereview.com/reference-speakers/crossovers-are-evil.html
http://www.prosoundweb.com/article/print/crossovers_the_series_an_introduction_to_the_basics


So if you're using 24 or 48dB/octave crossover points, you should have 360 or 720 degree shifts.

Thanks. You're right, I mis read. It says the high pass filter would have +90 shift and LP would be -90 shift.... Equaling 180.

The thing I'm unsure of is what X-over the factory amp is applying before the signal gets to the DSP. I guess I could assume 6,12,18, or whatever and play with the phase in the helix and see what happens.

Ima check out that link too. Try to wrap my brain around this.
 

·
Registered
Joined
·
7,202 Posts
I'm right there with you, because soon I'll be in the thick of it too with my Durango.

I'm researching all I can on the topic, in case it needs to be fleshed out.


edit: having a ball with this link, it ties many of the things Andy taught over the years about directvitiy.

http://www.rane.com/note160.html


Thanks. You're right, I mis read. It says the high pass filter would have +90 shift and LP would be -90 shift.... Equaling 180.

The thing I'm unsure of is what X-over the factory amp is applying before the signal gets to the DSP. I guess I could assume 6,12,18, or whatever and play with the phase in the helix and see what happens.

Ima check out that link too. Try to wrap my brain around this.
 

·
Registered
Joined
·
950 Posts
Discussion Starter #210
Made great progress last night. Unhooked the rear door speakers and used 5 sheets of deadener on the doors and door panel.

Played with the midbass first since they're covering the largest freq range, switched phase 180 on driver side and bam....beautiful pink noise sitting dead center of the dash, about right where the windshield meets the hood. That was easy.

Tweeters, not so much. Switched them 180, not the same result. Switched polarity at the amp, changed some X-over slopes, not much. Left the slopes at 24db LR and changed phase until it sounded close to center. I never could get the tweeters to "disappear" like the mids did but got pretty close. At least now when I play the phase tracks, the voice is in the middle of the dash.

Figured if I got the rta out and level matched it may help some. Response pretty much is what I expected. Tweeters were bright as hell, wound up attenuating them about 20 db. And upper midrange is a little lacking. Need to get the GB25 in pronto...



Honestly, I've never had anything sound this good with such little tuning and zero EQ. About 1 hour total. Easily the deepest sound stage I've ever had. Just about outside of the windshield. Overall, it's a pretty smooth response. I'll leave it as is until the GB25s are in.
 

·
Registered
Joined
·
113 Posts
Nice!. Do you have the sub playing yet. Can't wait to hear it all. :laugh:
 

·
Registered
Joined
·
950 Posts
Discussion Starter #212
Nice!. Do you have the sub playing yet. Can't wait to hear it all. :laugh:

Yep. Subs playing. Hit me up when ur around the area and I'll give u a demo. Still a good bit of work to do but U can hear it in Phases from start to finish.
 

·
Registered
Joined
·
7,202 Posts
I'm thinking the tweeters aren't disappearing because it is a reflection you're hearing, throwing the stage in phase tracks. But acoustically when you're listening to music, I bet it still holds the stage nicely.
 

·
Registered
Joined
·
113 Posts
Yep. Subs playing. Hit me up when ur around the area and I'll give u a demo. Still a good bit of work to do but U can hear it in Phases from start to finish.
Sounds good. Will try to set something up soon p.m. me your number.
 

·
Registered
Joined
·
950 Posts
Discussion Starter #216
I'm thinking the tweeters aren't disappearing because it is a reflection you're hearing, throwing the stage in phase tracks. But acoustically when you're listening to music, I bet it still holds the stage nicely.

I think your right. Still, during music the image is diffused and a bit scattered. Still have some work to do. At least it's at a point I can enjoy it until I get the pillars done and really dig into it.

Looking good my dude! Can't wait to hear it!
Thanks man. Can't wait to show it off!

You, jon225, and myself just may be the only 3 people in Louisiana that can appreciate a SQ oriented build. Lol



Sounds good. Will try to set something up soon p.m. me your number.

Done. Always looking for another set of ears
 

·
Registered
Joined
·
950 Posts
Discussion Starter #217 (Edited)
Brad you my friend need an air-nailer and compressor for Christmas. The ~$35 brad/staple nailer from Walmart + a quality hose from Harbor Freight or similar + a nice compressor (not from Walmart, lol) = super duper awesome time saver not having to use screws and countersinks all the time, and brads are so much cheaper, it actually ends up paying for itself in a short time both in time saved and in just cost of materials.

Santa could also see fit to give you a router lift (just bought a Jess Em myself) and big table to use it. You certainly have the skills to work it.

Bit the bullet. Little late for this build but whatever. The used one I picked up sat too long and the moisture eroded the tank so as soon as it got to 20 psi, the water works would start.

 

·
Registered
Joined
·
1,321 Posts
Bit the bullet. Little late for this build but whatever. The used one I picked up sat too long and the moisture eroded the tank so as soon as it got to 20 psi, the water works would start.

Some people do projects to actually complete said project. I do projects as an excuse to get MOAR tools. :)
 
201 - 220 of 726 Posts
Top