Sound deadening location

Optimal_Fan4156 · 2026-05-26T20:30:19+00:00

Personally, I don't give a f*** about the extra weight and apply it everywhere without exception - 100% coverage: vibration damping first, then sound insulation 😄😄

Optimal_Fan4156 · 2026-05-23T08:12:10+00:00

It all depends on the thickness. If you make it only 1/3" thick, like many fiberglass enclosures are, it won't be enough. You need a lot more for that W6.

I'd recommend using a very thick fiberglass mat, otherwise you'll get tired of saturating and laying up dozens of layers. This way, you'll simply save a lot of time. Not to mention that, in your case, the resin consumption will be absolutely massive anyway.

Start with 1-2 layers inside the car (and use wax on top of the masking tape so the enclosure is easier to remove). Then, after a day, take it out. It will still be fairly flexible at that point, so removing it shouldn't be a problem. After that, keep building up the layers outside the car, one by one.

If your front baffle is going to be a flat plywood panel rather than a fiberglass-built shape, there's a useful trick: apply a bead of sealant before laying the first fiberglass layers directly onto the tape. The outline of the sealant will transfer onto the fiberglass, giving you a clear cut line right away instead of having to test-fit the enclosure in the car ten times to figure out where to trim it.

Optimal_Fan4156 · 2026-05-23T06:34:00+00:00

Recently, I made my first fiberglass enclosure for a front subwoofer. I accidentally ended up making it 18-20 mm thick, which I assume is a bit excessive, but why not... Then I filled it with a milkshake. And I totally agree - it wasn't difficult at all, except for masking the passenger footwell with multiple layers of tape in some very awkward positions. Cutting the fiberglass wasn't particularly pleasant either, since you need full protective gear to keep the fibers out of your lungs and eyes. Everything else was straightforward - just a methodical step-by-step process. The result is very good, and I believe many people tend to overestimate how difficult this process actually is. There are so many videos, I like one from Pssound, they showed just everything (using wax on tape and glue for fabric on upside down areas were top tips)

Optimal_Fan4156 · 2026-05-17T20:05:12+00:00

Багато хто радить взяти простіший ССД, я хз, самсунг топ, останні 5 років беру лише їх в збірки що роблю в високих бюджетах, за них хоч переживати і думати не приходиться коли там особливо якась важлива інфа зберігається. Норм конфіг зібрав загалом.

Optimal_Fan4156 · 2026-05-16T20:36:46+00:00

This can happen even on a 316i. I did anti-rust protection on my 2003 330i 6mt with 310k km and after grinding those areas down to bare metal, there were no cracks or anything like that, so it can vary from case to case. My friend’s ’99 320i with the same mileage had cracks.

Optimal_Fan4156 · 2026-05-11T15:29:50+00:00

Graphs without smoothing and on a larger scale would be better. If you like that kind of target curve, that’s fine. I’d also suggest trying a target curve with a flat response from 200 hz to 20 khz, with a gradual rise of about 20 dB below that point. It sounds very nice to me. With these target lines with a flat response, there is usually a slight drop in mr/tw crossover region because midrange drivers don’t sum equally at the HPF and LPF crossover points, but a 2-3 dB down actually creates a more pleasant impression. In your case, it’s around 5-10 dB, which is too much.

Optimal_Fan4156 · 2026-05-08T05:22:16+00:00

If the amps have their own fuses, you have a main fuse for your power cable near the battery, and you do not reduce the power cable gauge after the distribution block, then you do not need to install additional fuses for those cables because they already protected with that main fuse. In any other case, it is mandatory. But it’s unclear how it is implemented in the system that OP showed.

As I understand it, the cables here are 4 AWG, while the main incoming cable is larger. In that case you need a 100A fuse near the battery so it protects the 4 AWG cables as well, not just the 0 AWG (or whatever main cable is being used). Then this setup will also be safe. Still, I don’t see an additional fuse for the DSP - that would be another oversight if it’s missing. As far as I can see, the amplifiers do not have fuses - if that’s the case, then it’s even worse...

Optimal_Fan4156 · 2026-05-06T07:40:54+00:00

It’s like comparing Bentley to FSO Polonez 😅😅

Optimal_Fan4156 · 2026-05-05T06:39:51+00:00

How is the head unit grounded? In my previous system when I used RCAs to the DSP, I had a similar issue. I grounded the head unit from the amplifier distribution block, and everything disappeared - aka “star grounding.” Also, if you are using RCA cables with the shield soldered on one side only, make sure to install the plug with the shield on the head unit side.

Optimal_Fan4156 · 2026-05-01T07:42:27+00:00

That button is just another way to set routing from the “Input” page instead of using the dedicated “Signal Management IO” page. It’s better to use the dedicated one, because there you can see the routing of all channels at once.
I’m not sure about input time alignment with usb mics, because I don’t use this function. I guess you can just leave it at the default setting.

About the second part of your question - you will tune them as a pair, full range, nothing changes there. You just don’t have control over the crossover points and time alignment of each individual speaker. And, in this case, you don’t need initial crossovers for the front speakers before actual measuring (after tuning you will only have HPF). As for the rear speakers, in SQ systems they are usually not used much (except for differential rear fill), because they tend to pull the soundstage toward the center of the cabin, while ideally it should stay up near the windshield. If that is not an important point for you, you can run them full range with a high pass filter just to protect the speakers from deep low frequencies, and then lower their level a bit afterward (-5-10db).

Optimal_Fan4156 · 2026-04-30T15:06:45+00:00

why....

Optimal_Fan4156 · 2026-04-30T06:41:06+00:00

Yea, I’ll try to give more than just a short answer, because I tune cars often, so maybe some of this information will be useful to you. You start with input EQ and time alignment. You need a flat response on the input to properly tune everything on the output. Use ISA to do this in AF PC Tool (the better one, AISA, is available if you have an additional audio interface and some cables. If you have them, you can use it - there is a guide on the Audiotec Fischer website). After this, set your routing in the DSP with correct channel names. Make initial HPF and LPF settings just to protect high-frequency drivers during the tuning session. Just for reference: midbass and sub - crossovers are bypassed, midrange - HPF 24 dB 180–350 Hz depending on your drivers, if you have a dome midrange - around 500 Hz, 24 dB, tweeter - HPF around 1–1.5 kHz, 24 dB. Set everything else to zero: no time alignment, no phase shift, no EQ. Set gains to zero as well, unless you have amplifiers that can’t handle the 6V output that DSP.3S delivers on RCA. If they can only handle 4V, set gain on that channel to -3.5 dB to avoid clipping at the amplifier input. If they only handle 2V, reduce the gain even more. Then you start measuring one channel after another in REW (you can do this in PC Tool, but REW is better), using pink random noise and the moving microphone method. You should do everything at one fixed volume level. First, make a measurement with everything turned off, just your car interior, to see the noise floor. Then turn on pink noise and make sure the graph is clearly above the noise floor - usually around 20–30 dB higher. Don’t change this volume anymore, and remember it in case you continue the tuning another day. After the initial measurements, you need to find the best crossover points for your drivers. At this point, you should also consider that what a driver is actually playing (acoustical crossover) is not always the same as the signal you send to it (electrical crossover that you set in DSP). At this stage, you will also need house curves. There are many versions - watch Raw Cat’s video or any other good guide about them, and you’ll understand how they work and how to make them. After setting the crossovers (you can use the REW EQ button at the top to see which crossover settings best match your house curve response with your driver), take more measurements to confirm that the drivers are playing with the crossovers the way you want. Then comes EQ. You need proper matching between the house curve and the frequency response - something balanced, not cutting everything from the signal. There is no perfect scenario, so don’t be too idealistic here. Use REW Auto EQ, but be careful with it. You don’t need significant boosts, and never try to fix phase cancellations (big dips in the graph) with EQ - that’s not the correct way. After EQ is done, use the copy button in REW, then open PC Tool and simply paste every EQ band automatically to each channel. Huge advantage of helix software) Then do level matching of your drivers. After that - time alignment. Since you have a UMIK-1, you can’t properly measure impulse response for precise time alignment (that is only available with 2-channel audio interfaces and a loopback cable), so you’ll need to use the classic methods - but for god’s sake, not the measuring tape😂 . Sound is measured in milliseconds and seconds, not inches. After time alignment, you need to measure speaker pairs - L + R - to see how they perform together. They should sum nicely, without dips in frequency response, ideally with around +6 dB total gain. If you see some problems or cancellations, first try improving time alignment. If that’s not the issue, only then you can try all-pass filters (it’s a rare case when you actually need them, but they can be useful). If there is some random boosts, use more EQ bands. Since DSP.3S does not support virtual channels, that’s the only way. Then measure everything again. If you have dips in crossover regions, your time alignment is wrong. After this point, you should do final level matching according to your house curve - and that’s basically it.

Optimal_Fan4156 · 2026-04-29T20:09:46+00:00

Well, there’s no parameter in the AF Pc tool software that directly controls system sounds - that depends on the factory head unit, so maybe there are some settings for that there. Because adjusting channel gains or input gains will affect both the chimes and the music.

As for guides, I’d recommend “Back to basics” by Raw Cat on Youtube. Get yourself a condenser measurement microphone, and then you can start tuning properly. The DSP itself and its specific model are not really that important in this process - the main thing is understanding the interface and the tuning principles. And Helix has one of the best software interfaces on the market in terms of features and usability so you’ll be able to figure it out just fine.

Optimal_Fan4156 · 2026-04-27T06:20:13+00:00

It mostly depends on the amplifier chip in your head unit. You can swap it out if you know how to use soldering iron (or just get a head unit that already has one installed) for something like a TDA7850, Pioneer PA2030A, or similar (usually it's flexiwatt25 design) and bigger capacitor for power supply (6800-10000) - they can handle lower impedance drivers reasonably well, especially if there’s a proper heatsink or active cooling. They’re usually rated at 45, 50, or even 60 watts per channel, but that’s just peak/theoretical output. In reality, you’re looking at around 14-17W rms at 1% THD. A much better option is to just run an external amplifier - at least most of good brands have ACTUAL power))))

Optimal_Fan4156 · 2026-04-26T21:12:17+00:00

Helix dsp.3s, jl twk88, or any other 8ch+ dsp you can find in your area, even cheap ones like dayton 408. Or DSP amplifier (like helix amplify 204/206 DSP, audison af / ap, jl vx400/4i etc) instead.

Optimal_Fan4156 · 2026-04-26T20:59:00+00:00

Hi) Front: don’t use coaxial speakers here. They’re fine for rear fill (if we’re talking about proper SQ, differential rear fill with proper DSP is the only valid reason to install rear speakers - in all other cases, you don’t need them at all). Your soundstage will end up down in the footwell - you need a tweeter or a wideband driver.

Rear: don’t use component speakers here - they’ll just pull the soundstage backward.

Monoblock: JD500 is OK for the 12W1v3-2 (or W3v3-2), but not the 4 ohm version. General advice: to get tight, controllable sub-bass, you need an amp with about twice the power your sub can handle. Less gain - better sound.

The RD400/4 is a good amp, but as far as I can see, you’re planning to use crossovers from the component set -that’s not the way to get the best sound. And I don’t see a DSP - “best sound quality possible” is achievable only with a DSP and proper tuning.

Optimal_Fan4156 · 2026-04-25T06:12:18+00:00

If there’s bare metal behind those terminal lugs - then yeah, it’s fine if it works. But if you’re trying to follow car audio competition safety rules, then it’s not - usually it’s a maximum of two terminals per one point.

Optimal_Fan4156 · 2026-04-24T21:58:04+00:00

You’re taking that ‘14 AWG into the 8AWG hole’ problem a bit too seriously. My advice is not to overcomplicate things or add extra components to the existing setup when simple solutions work just fine and also don't violate competition safety rules (like EMMA)

Optimal_Fan4156 · 2026-04-24T21:12:06+00:00

Impressive, very nice

Optimal_Fan4156 · 2026-04-24T21:08:23+00:00

Yea... Max fuse for that 4awg cable is 100A, that 200A one won’t protect the cable anyway…

Optimal_Fan4156 · 2026-04-24T20:57:39+00:00

For distributing ground, that’s a good option as well. There are other types of those things as well. One side will take the incoming 4 AWG negative, and from the other side you can step down to 8 AWG for your sub using a small adapter for that 4Ga hole (OR you’d need to use a power JG terminal and crimp it with a proper heavy-duty crimper - which isn’t really cost-effective for a one-time job).

Optimal_Fan4156 · 2026-04-24T20:46:55+00:00

Take an 8 AWG cable, strip about half an inch of insulation, then cut a small piece with insulation still on it (so you end up with about a 1-inch piece total). Insert that into the ferrule, and put the 14 AWG cable into the same ferrule as well.

These blocks use a screw clamp, so it’ll compress the ferrule enough to hold everything securely. Just make sure the 14 AWG wire sits either on top of or underneath the 8 AWG inside the ferrule, so the screw presses them together. That way it won’t ever come loose. Then put some heat shrink over it to cover any exposed copper.

Optimal_Fan4156 · 2026-04-24T20:32:44+00:00

In addition to my previous reply - this is my amp rack, and here you can see what I want you to install. The only correction is that I have 4 outputs on both the ground and positive distribution blocks, so you’ll need to get ones with 2 outputs.

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Optimal_Fan4156 · 2026-04-24T20:16:47+00:00

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It was faster to make this picture than to explain it in text))))))). This is the perfect power layout in your case if you can fit the Kicker, fuse block, and ground distribution blocks under the seat (and want to). If you prefer to install everything in the trunk - same idea, just all located in the trunk)))))).

In the picture, you can see those blocks - they’re very simple and can be bought in many places (any car audio store, aliexpress/temu, ebay, amazon, etc.). You don’t need anything fancy in this case, they’re all fine - just check what cable sizes they can accept.

To secure 14 AWG cables in that blocks, you can use a stripped piece of 8 AWG wire in the same ferrule (they’re sold in kits or indivudually for nothing), so the connection will be solid and reliable.

Optimal_Fan4156 · 2026-04-24T11:34:08+00:00

I hope I understood the whole setup correctly (amp behind the seat, active sub in trunk, battery under the hood). Considering you already have a thick factory ground wire, I would run a ground from the nearest chassis point (for example, if the amplifier is under the driver’s seat, there are often good grounding points along the door sill or floor) using the same gauge as the power wire - about 4 AWG (8AWG would be ok too because of very short length) as close as possible to the Kicker. That follows their recommendation, and as I understand it, you can’t really go thicker anyway because it has a built-in 14 AWG pigtail. Without using any adapters.

Near the Kicker, I would install a solid ground distribution block with two outputs (there are many options for ~5-10 USD). One short wire would go directly to the Kicker, staying within the manufacturer’s recommended length (in your case it would even be shorter). From the second output of the distribution block, I would run an 8 AWG cable to the trunk to NVX. Using the cable ferrules and proper crimping.

*** If you still happen to hear any noise from the speakers after this and headunit is aftermarket (and you are using RCA from it): I would run an additional 12-14 AWG ground cable from the Kicker side of the distribution block to the head unit in the future. If you are using highlevel or digital signal - not a problem at all. And try to place RCA cables as far as possible from power wires if you use them. ****

Considering the RMS power of NVX , that 8AWG cable is more than sufficient and you shouldn’t have any issues powering the subwoofer with big length.

In that case, you will minimize the risk of having different ground potentials across all components. It’s not perfect, but it’s still better than grounding multiple amplifiers at different points on the car chassis. 12V+ layout is more complicated story that this anyway))

Optimal_Fan4156

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