New Audio Build log

[wykdtr0n]

I spent the weekend pulling trim and running wires to replace the factory Bose system. I was originally going to wait a while to source some better components, but I have a 2 way system that was originally intended for my 99 4runner that I'm going to put in the Z for now until I decide what direction I ultimately want to go. Having the foundation flushed out will make future adaptions fairly easy, I hope. I want to thank everyone who has contributed to the knowledge base here in the various audio build threads.

My components:

Helix M Four DSP 4x100w RMS Class D
Helix M One X 1030w RMS @1ohm
Morel Maximo Ultra 602 MKii 6.5" 90W RMS 2-Way Component Speakers
Stereo Integrity SQL 12 Series 2 1000w RMS

For now I plan on running the tweeters in the dash locations, although I'm certain in the future I'll opt for a 3 way setup with mids in the dash and tweeters at the a-pillar. I'm uncertain how well the Morel tweeters will perform off-axis, so I may end up replacing them sooner rather than later. I don't plan on running rear speakers, I'll disconnect the factory rears once everything else goes in.

The sub is in a 1 cubic foot sealed box for now. It fits in the trunk, eventually I'll opt for a hidden sub setup similar to what Mr. Mac has provided us with.

My main power wire is 2 gauge extreme from batterycablesusa. It's pretty beefy and I wasn't certain how easy it would be to run, but it fit easy enough with the trim pulled and the seats out. I was pleasantly surprised with how flexible it is. A 200amp ANL fuse set up next to the battery, run through the rubber grommet behind the battery. I haven't attached the power to the battery yet, Mr. Mac indicates he used the empty threaded stud on the positive fusible link block, but I'm not 100% certain that bolt is unfused and I want to insure I won't run the risk of blowing anything there since my system is running a little hotter than Mr. Mac's. For now the wire is safely zip tied away from the positive/negative terminals. Also the asshole that installed the gps tracker on the car absolutely destroyed the battery terminal connectors.

Speaker wires are 14 gauge to the components, 10 gauge for the subwoofer. All KnuKonceptz Ultra Flex. I'm one of those heathens who feels fine running the speaker wire right next to their power wire, so I have two sets of speaker wire running down each side of the vehicle. I probably should have run 3 in case I go to a 3 way active setup in the future, but I'll cross that bridge when I get there. For now, the wires are zip tied up under the foot well trim panel, I haven't run them through the dash or doors yet since the door will require drilling holes in the wire plugs and I was running out of time.

I haven't put any sound deadening materials in yet. I know that should be the first thing I do, but I'm undecided between using the Kilmat I have on hand or getting some resonix CLD squares.

Next step will be setting up my amp board, for now it'll just go under the trunk mat in the spare tire well, nothing fancy as it'll be temporary until I get a hidden sub box in place.

Videos I found useful:

Removing the Nissan Z seats -
Removing rear trunk trim -
Removing door panels -
Removing battery trim -

 

[Exquisite_Red]

Nice! I have the SQL-10 in mine and absolutely love it, good choice.

 

[wykdtr0n]

Nice! I have the SQL-10 in mine and absolutely love it, good choice.

I bought it over a year ago and still have yet to hear it! I'm stoked to get this finished.

 

[wykdtr0n]

Amp rack is cut out and test fit. I should be able to get it wired this weekend. It's janky but will work for now. I also broke down and bought the Stereo Integrity M28 and TM65 MkIV to use instead of the Morels. I wanted to go with Audiofrog's GB60 and gb10/ or 25 but the GB60's are out of stock everywhere and apparently being replaced with a new model.

 

[RHE2026]

Since the Bose woofer in my Z is definitely lacking balance or capability can I improve the sub with a EQ from an app if I don’t want to swap the amp,woofer etc ? Also I noticed how really lacks what my 2005 350 had stock with its 6 CD changer. Also does the new Z have a powered or passive sub. Thx

 

[wykdtr0n]

Since the Bose woofer in my Z is definitely lacking balance or capability can I improve the sub with a EQ from an app if I don’t want to swap the amp,woofer etc ? Also I noticed how really lacks what my 2005 350 had stock with its 6 CD changer. Also does the new Z have a powered or passive sub. Thx

The stock Bose subwoofer is an active, powered subwoofer. It gets a signal from the stock amplifier located near the top left of my trunk pic. You can improve the stock Bose sub performance with an EQ app, but it's still limited in it's range. It'll get louder but it stays pretty tight and tends to lack the fullness of more quality subs.

 

[wykdtr0n]

Amp rack is in and fully wired. It's messy, but all wire connections are either ferruled with heat shrink tubing or otherwise appropriate terminal connections. I enjoy running wires in 12v applications and the satisfaction that comes with a well terminated wire

I attached the 2awg ground wire to the stock amp bolt that @JChandler82 utilized in his thread here:

https://www.nissanzclub.com/forum/threads/basic-budget-diy-subwoofer-install-anyone-can-do-it.9321/

After using a wire wheel to clear all the paint off, a used a multimeter to test restistance and confirmed it was a good ground, so I applied dielectric grease and reattached the stock amp over it.

I tapped into the front left/front right signals just before the stock amp as Mr. Mac indicates in this post:

https://www.nissanzclub.com/forum/threads/factory-audio-system-questions.2432/post-73282

I don't solder well so I used solder crimp connectors, then used heat shrink tubing over the top of them and further wrapped it with wire loom tape before plugging it back into the stock amp.

Since I haven't installed new speakers yet, I turned everything on to confirm the stock signal to the Bose amp was still working, and everything came through clear. Once I finish running speaker wires to the door and dash locations and replace the factory speakers, I'll be fully bypassing the stock amp on the front left/right channels. Unfortunately, getting this much done took way longer than I expected so I won't have a chance to finish up the speaker wires until tomorrow probably.

 

[Who.Am.Eye.2716]

Great build. Cant wait to see the finished look

 

[JChandler82]

Looking good

 

[wykdtr0n]

I had time to pull my door panel off and get one speaker wire run through the door wiring loom. I was worried about this as my hands aren't exactly small and drilling out the plugs is a little intimidating, but the Z plugs seem to have a lot more room than the 370z. The door side plug has an open space to run wire, so no drilling needed. The body side plug needed drilling but there is plenty of room.

It's a pretty intensive process, having an extra set of smaller hands would have been helpful getting the plugs reattached and the body side plug in and out. I managed it on my own although my hand is pretty scraped up.

This video that Mr Mac shared has the basics of everything you need to get it done:

 

[wykdtr0n]

I've been busy so haven't had much time the last few weeks but finally got some time to make progress today. I fabbed up some adapter plates for my Stereo Integrity tweeters, ran speaker wires up through the dash and installed the new tweeters. I'm committed now so hopefully should be able to run the passenger door speaker wire tomorrow and get both 6.5's fully installed.

 

[wykdtr0n]

Well everything is in and sadly I'm dealing with signal issues...sub amp is shutting down and/or going into fault when I plug the rca's in from the M Four DSP. There's also a constant hiss in the front speakers that doesn't change with the volume knob.

I've set crossovers/slope in ATF's DSP PC-Tool 6, set up IO and virtual channel routing, but it's all new to me so I'm hoping it's just a software issue and not a hardware issue. I've got a better Digital Multimeter coming today so I can check voltage coming from the RCA's i patched into the stock pre-amp signals. My current multimeter doesn't seem to read low enough.

Sound is playing well in the front stage (aside from the hiss) and much clearer than the stock speakers, although the tweeters are too bright so it needs tuned. Volume doesn't seem to get as loud as I expected but I haven't set gains yet, it's done digitally with the M4 DSP which is moderately annoying.

 

[Exquisite_Red]

Sorry to hear about the issues. I had a few gremlins myself after I did my full replacement, it's inevitable with a project like this.

Does the hiss in the front speakers persist even when you remove the inputs from the amp? Test that, and then you can know if the hiss is originating from the source or the amp itself. Also, "hiss" indicates a high pitched noise. Is that right? It's not a hum? Hiss is usually a signal issue, while hum is usually a wiring/electrical issue.

Regarding the amp going into fault, are you 100% sure this is happening due to the RCAs? Any chance that's an incorrect diagnosis? The reason I ask is I had a similar condition in mine. The amp would randomly go into fault and I couldn't figure out why. Like 40% of the time, it would work perfectly, and then the rest of the time it would go right into fault at startup. After a lot of research, I suspected that voltage sag from the starter was throwing the amp into fault. I put a cheap timed relay on the remote wire. I set it so that the amp doesn't get the signal to turn on until a few seconds after the car is started and voltage has stabilized. I have had zero faults in the six months since I installed this.

 

[wykdtr0n]

Regarding the hissing, it's only coming from the tweeters and goes away if I remove inputs from the amp. When I'm in ATF's DSP PC-Tool 6, I can mute the tweeter channels directly and the hissing stops. When I adjust the output gains for individual channels I can reduce the hissing but it doesn't go away entirely.

I measured my input voltage at the RCA's going into the Helix M Four DSP. (These are tapped just before the stock amp). It's pretty low, around .5 volts, even at 80% volume. The Helix M Four expects 1 to 4 volts, and I know .5 isn't a big deal and that adjusting input sensitivity should overcome that. Unfortunately, DSP PC-Tool 6 tries to do that for you automatically. I know there's ways to do it manually but I haven't found them in the software yet. My theory is the automatic input sensitivity adjustment is raising the sound floor too much, but I could be wrong. Unfortunately I can't find an easy solution for this unless I got to version 5 the DSP PC-Tool where input sensitivity is much easier to manage.

The sub amp only goes into fault when it gets a signal via RCA's from the dsp. If I remove the RCA's it fires up and stays connected without issue. I measured RCA outputs and adjusted them in the DSP so they're right around 1 volt. The gain on the amp is currently all the way down, it should be almost all the way up to match the input signal and starting with the gains in various positions but as soon as it gets an audio signal it faults. I had one instance where it stayed on and I got a 50hz test tone playing through it while I moved the gain knob to see if it would clip (it didn't even at max) which is when I realized I needed to measure actual output with a DMM. As far as I know it shouldn't go into fault from under powered signals, so I assume it has to be something else. I also tested resistance at the sub and it's within range.

I'm going to try moving my main ground to a different position to see if that clears up anything, it's currently grounded under the stock amp frame and the stock amp is still completely plugged in. I wire wheeled the shit out of it to make sure the metal was bare, but I'm not sure that the frame touching the ground and the still active stock amp isn't causing an issue. I'm also going to pull all connections to the sub amp and reconnect to insure I don't have any shorts. Then I'll check for DC offset at the RCA's.