Sport Model: audio solution thread

[Mugzilla]

Are the previously-mentioned Pioneers just as good as anything else considering there’s no amp?

They are miles and miles better than the stock speakers.

Like I said, The in-dash speakers added the most bang for the buck. Door speakers were second. (EDIT: BEcause I'm an idiot, and used 4 ohm speakers instead of 2 ohm. Will report back when I remedy this.)

In hindsight, I should have added some sound deadening inside the doors when I had the panels off. (Someone here did a ton of sound deadening in the spare tire well. They took great pictures.)

 

[Exquisite_Red]

I’ve got everything on the way to do the front speaker replacement. No amps or DSP for now, just going to see how much improvement there is just with the speakers. I picked up a bunch of sound deadening material as well, so we’ll see what difference that makes. I do audio engineering on the side, so I have the gear to make before and after measurements. I plan to measure:

• Stock speakers
• Stock speakers w/ sound deadening
• Aftermarket speakers
• Aftermarket speakers w/ sound deadening

I’ll post a write up and all the REW measurements here once I’ve got it done. Hoping to do it this weekend!

 

[Mugzilla]

I would say "Stock w/ sound deadening" is a waste of time. If you are opening the door to add $15 worth of rubber matting, you would probably just open the door panel to install a $30 set of speakers.

 

[staying_tuned]

@Mugzilla thanks for taking the time to aggregate your notes, photos and thoughts into this post. I'm hoping to tackle doors & dash in the coming months and this will be a ton of help.

 

[Exquisite_Red]

I would say "Stock w/ sound deadening" is a waste of time. If you are opening the door to add $15 worth of rubber matting, you would probably just open the door panel to install a $30 set of speakers.

That shot is mostly just for science. Probably impractical, but you never know. In the studio, the answer is almost always more sound treatment before better speakers.

I’ll also probably do an aftermarket dash speaker + stock door speaker shot since the consensus seems to be that’s where the best value is. I followed your lead and also went for the TS-A709 for the dash. I love the idea of a 2-way in the dash.

 

[RobotAZ]

Why do any sound deadening at all?

 

[Mugzilla]

Why do any sound deadening at all?

Check out what @staying_tuned did in this thread, as well as his comments:

https://www.nissanzclub.com/forum/threads/what-did-you-do-to-your-z-today-🙋🏻‍♂️.2677/page-19

 

[Exquisite_Red]

@Mugzilla, I was prepping for the install and made an interesting discovery… While the dash and rear speakers are 4 ohms, the factory door speakers are 2 ohm. Makes sense, since they would want most of the power directed to the biggest drivers, but I had never considered there would be speakers of different impedance within a single system. I’d imagine that’s why you weren’t as impressed with your door speakers as the dash ones; they are only getting half as much power as the stockers!

Unfortunately, the speakers I already ordered are 4 ohm. I’ll probably just hold on to them for when I add an amp down the line. Far fewer aftermarket options at 2 ohm, but I’ll see what I can come up with.

 

[Mugzilla]

@Mugzilla, I was prepping for the install and made an interesting discovery… While the dash and rear speakers are 4 ohms, the factory door speakers are 2 ohm. Makes sense, since they would want most of the power directed to the biggest drivers, but I had never considered there would be speakers of different impedance within a single system. I’d imagine that’s why you weren’t as impressed with your door speakers as the dash ones; they are only getting half as much power as the stockers!

Unfortunately, the speakers I already ordered are 4 ohm. I’ll probably just hold on to them for when I add an amp down the line. Far fewer aftermarket options at 2 ohm, but I’ll see what I can come up with.

Holy crap.

Wonder if I got 2ohm rear speakers if that would wake them up....

 

[Exquisite_Red]

Holy crap.

Wonder if I got 2ohm rear speakers if that would wake them up....

It would definitely wake them up, but who knows if the amp could handle it. I don’t want to assume that just because the door channel can handle a 2 ohm load, so could the rear channel. I’d hate for you to damage your amp!

IMO, if you replace the door speakers with some aftermarket 2 ohms it’ll probably improve the sound so much you won’t even be worried about those rear speakers anymore!

 

[Mugzilla]

@Exquisite_Red

Do you still have the stock 3.5" speakers? Are they 2 or 4 ohm? (I threw mine in the trash 2 weeks ago.)

 

[Exquisite_Red]

@Exquisite_Red

Do you still have the stock 3.5" speakers? Are they 2 or 4 ohm? (I threw mine in the trash 2 weeks ago.)

Yes, the 3.5” rear speakers are 4 ohm. It’s only the front door speakers that are 2 ohm.

 

[Exquisite_Red]

I completed the speaker install over the weekend. I won’t bury the lead; the results are not very impressive, especially considering what I spent.


TLDR;

Dash speakers: Louder than stock, but in a harsh way. Lots of spikes in the upper frequencies giving a shrill overall character. If I hadn't destroyed my stock speakers, I would probably put them back in.

Door speakers: Quieter than stock, probably due to a less efficient design. Tighter/cleaner than stock, but with a significant dip in the 40-80Hz range.

Overall: This was a lot of money and a lot of time spent to get pretty poor results. Even though the low end is tighter and cleaner than stock, I don’t think it’s worth the disruption to the frequency response of the mid and high end. At least with this particular combination of speakers, I don’t believe it’s worth the money to upgrade unless you also intend to also implement amping and DSP. I basically paid several hundred dollars to make my audio system sound objectively worse.


INSTALL DETAILS

My goal for this project was to improve sound quality by replacing the cheap OEM paper cone speakers. I also planned to apply sound deadening treatment to the doors to reduce road noise and unwanted vibrations.

For this project I chose the Pioneer TS-A709 for the dash and PowerBass OE-6C woofers for the doors. I chose a two way over a tweeter for the dash because I prefer a much lower high pass frequency on the front speakers so I get as much of the high frequency directional content at ear level as possible, creating a better soundstage and leaving the door woofers to fill in the low end. The included HPF for the TS-A709 is at 850Hz. If I were running DSP, I’d probably go an octave lower down to 400Hz, again, to get as much of the high end as possible up at ear level.

I have “bypassed” the rear speakers by moving the fade on the head unit 100% forward. The rear speakers are practically useless the way they are mounted with no enclosure and I’m more interested in a proper soundstage than a tiny bit of rear fill, so I’m not addressing the rear speakers as part of this install.

Here are the install materials (left to right):

• Roadkill FastRings foam rings and rear reflection pad for door speakers
• Dynamat trim removal kit
• Factory speaker harness adapters
• Roller for applying the Dynamat material
• Dynamat door kit x2
• Soundskins foam tape
• Fabric tape
• Clear transfer tape for transferring door panel outlines to the Dynamat sheets
• Hole punch kit for cutting holes in the Dynamat to accommodate the various bolt and tab holes
• SonicBarrier, a cheaper sound deadening alternative to Dynamat (not used in this project, I purchased for when I sound deaden the trunk area)

Here’s the mic placement for all of the measurements I took, approximately at ear level. The mic was not touched or disturbed during the install, to maintain the integrity of the before and after testing.

This is just a shot of my audio software running in the car. I felt like Brian Earl Spilner with the laptop going.

First step was to replace the dash speakers. I didn’t document much here as the process is already covered earlier in this thread. However, I ran into my first issue: the harness adapter I ordered was not correct. I don’t know if Crutchfield recommended the wrong thing, or shipped the wrong thing, or if the OEM harness changed for ’24 model year. But it wasn’t even close. I already had the car apart and all the audio equipment set up, so I decided to just roll with it. I hacked the female plugs and terminals off of the factory speakers to create my own adapter harness. The body of the factory speaker is soft plastic, so the hack saw cut through the top part like butter, and then I was able to cleanly snap the plug off of the rear face of the speaker from there.

And here is my new adapter harness with the crossover wired in. The terminals were covered and the whole end was wrapped in cloth tape before install.

Next was the door treatment. Surprisingly, the factory door setup is actually pretty good. Typically a door will have large holes in the inner skin for access. A lot of the benefit of treating the door is to close up those holes so the door becomes an “enclosure” for the woofer. But in this case, Nissan integrated a cover (the silver part) that closes up the holes. It’s cool that they did this, but unfortunately means there will be less benefit to the sound treatment. But I decided to do it anyway because it could still reduce some road noise and resonances.

And here’s the finished door. This is BY FAR the most laborious part of the process and took much longer than I anticipated. You have to meticulously cut the Dynamat so that it fits to the section of the door, while also making cutouts for all of the holes and tabs, all on your hands and knees. Sounds simple, but it’s harder than it looks! Each door took several hours, but I’m sure you could do it quicker if you’re not being a perfectionist.

I didn’t get a good picture but I also put a strip on the outer panel right behind where the speaker mounts. Any more application to the outer panel would have required disassembling the door, and I didn’t want to tackle that job.

Next is the treatment of the speaker mounts. I put foam tape on all mounting surfaces and installed the foam ring surround that envelopes the rear side of the speaker.

I also put the thick foam circle directly behind the speaker position, but had to trim it due to interference with the window rail. I wedged the foam in place, marked the outer edge of the rail, and then removed about ¾” of material from the face of the foam inside of that mark. It worked out perfectly and the window goes up and down with zero obstruction. Who knows if this is actually accomplishing anything at this point, but I had it, so I figured why not go ahead and install it.

Here is the finished assembly in the door!

Here is a picture of the stock speakers for reference.

RESULTS

The following REW chart shows three measurements:

OEM system (red line)
Aftermarket dash speakers only (green line)
Full aftermarket speakers + door acoustic treatment (blue line)

For those unfamiliar with this type of graph, the y axis represents level and the x axis represents frequency.

All three measurements were taken at the same volume (25). They are the average of 20 seconds of pink noise. You can ignore the wonky curve. I forgot to zero out the EQ settings in the head unit before taking the initial measurement, but all three shots had the same EQ settings. The thing to pay attention to here is the difference between the curves, not the shape of the overall curve.

It's odd how much changed just by adding the dash speakers. There are significant new peaks at 950Hz, 2.5kHz, 5.2kHz. Oddly, despite being a two way design with a tweeter, the TS-A709 has a steeper roll off above 10kHz than the stock, tweeterless paper cones. This isn't necessarily a bad thing, as this could be perceived as "warm". However, the more dramatic peaks and valleys of the frequency response above 800Hz give a harsh impression, noticeably less smooth than the stock speakers. There is also an odd new dip between 300-400Hz, an important range for the "weight" of a mix; big notches like this can make the mix sound "hollow". From 300Hz down, the frequency response is mostly the same as stock, which I would expect since the stock door speakers were still in place. However, there is a big gain from 50-60Hz. This is bizarre. This is an extremely important area for bass, and for some reason, the stock door speakers performed significantly better in this area with the aftermarket dash speakers in place. This must have something to do with a difference in the crossover or load of the aftermarket dash speakers altering how the amp is interacting with the door speakers. This is purely a guess, but I don't know what else would have caused this, as the ONLY thing that's different between those two measurements is the dash speakers being swapped out!

Things only get worse once the door speakers are installed. There are dramatic new peaks and valleys across the entire frequency spectrum. The only thing I can think is maybe the sound deadening has altered the way the vehicle is resonating, but that would be the opposite of the intended effect. Look at how all of the peaks and dips between 300Hz and 2kHz are significantly emphasized. This is gnarly. Not in a good way. The ideal frequency graph is a nice smooth curve. All of these peaks and dips make the audio sound artificial and harsh. There is an almost 20db swing from 750Hz to 950Hz! That's insane! From 500Hz down, the aftermarket speakers are quieter than the factory speakers. Though the specs of the factory speaker are not published, my assumption is that it is a more efficient speaker than the aftermarket unit. And the big drop between 40-80Hz means noticeably less impactful bass. Though these new speakers are 2 ohm and are advertised to be used with the factory head unit, it seems the factory amp can’t quite drive them properly.

I guess the one good thing is something this graph doesn't show: decay. I couldn't measure this because REW refused to connect to the car's bluetooth. But the low end is noticeably tighter. So, the only way I could recommend these speakers is if low and low-mid sound quality is your absolute highest priority, with SPL as a distant second.

Overall, the stock system had a significantly more smooth frequency response. As you can imagine, this is pretty disappointing.

 

[Mugzilla]

@Exquisite_Red

WOW! Wish I could drag your post to the top one! You should be the Ringmaster of this circus!

Couple thoughts/things:

- What dash speakers did you use? 2.75"?

- Did you get the + and - correct on their wiring? Those frequency swings at the top seem suspect. Wonder if those crossovers are direction-dependent, or are "passing" monster amounts once they cross their cutoff threshold. (I doubt you wired incorrectly, as your attention to detail is incredible.)

- If you email/call Crutchfield and let them know that they are recommending the wrong wiring harness, they'll update. They are a "small" company, that was just down the road from me when I lived in VA.

 

[staying_tuned]

I don’t believe it’s worth the money to upgrade unless you also intend to also implement amping and DSP

Assuming the stock sport deck is only pushing 15-20w RMS, I bet if you dropped down to something more suited for that power @ that ohm load it would make a world of difference. It has been awhile but the last time I tried a set 50+ RMS / 1XX+ max on a head-unit putting out ultra low wattage they sounded like child walky-talkies. I'm actually surprised you're getting anything out of the door speakers, stock HU power is likely not enough to get the cone moving at all. A good test would be to go grab a set of ultra cheap Kenwood KFC-1666S for the door. If it instantly wakes up, they offer a 2-40 watt tweeter int hat KFC line as well.

Great news on the door being near sealed from the factory and once you get a set of speakers that match what you're working with I bet its going to sound incredible with the effort you put in. I'd rather have entry/mid-level speakers with fantastic deadening than the best speakers money can buy and no deadening. It's like a $-multiplier if you've got the time. Thanks for posting all of this information.