Down4soundshop

Hey all. Just checking to see if there are any car audio enthusiasts around who might be handy with a multimeteoscilloscope and willing to try and help out a newbie.
I've recently installed a subwoofer and amp in my car and while a lot of the low/deep bass sounds decent everything else sounds bad or non existent. I believe I need a lot of help with the tuning as I've kind of hit a wall and gotten overwhelmed with what to do next.
If anyone is willing to answer some questions or possibly meeting up to work on it let me know. I will try to explain where I'm at and what gear I'm working with.
2014 dodge charger
Stock head unit
Audio control lc2i pro line output converter tapped into rear speakers.
Jp23 v1.5 amplifier (2300 RMS)
2 12" sundown audio sa12 classics
Down4sound profab ported box tuned to 31-32hz
I bought the amp and subwoofer bass package from down4sound here are the links.
Amplifier
https://www.down4soundshop.com/down4sound-jp23-v1-5-2300w-rms-amplifie
Subwoofers and box
https://www.down4soundshop.com/sundown-sa12-load-enclosure-2-sa12-subs-profab-box-2000w-rms-31-hz-1-ohm/
Wired to 1ohm
So I ordered an oscilloscope and multimeter to help set gains and tune. I am barely able to increase my gain before I start to clip. I believe I have my subsonic filter set to around 25 and my low pass filter set between 80-100 but hard to be 100% sure. Also bass boost is turned off.
My next step was to try running some sine waves to the sub to adjust things and check for clipping with the o-scope. However with my stock head unit I'm not sure how to safely play those sine waves without disconnecting all my stock factory speakers or blowing them out.
Any advice would be appreciated. Thanks

Decided to go dual 12 SI SQL on a JP23… need box ideas ported or sealed? Don’t want to make a box this is what I’ve been looking at - any SQL guys out there… what say you?
https://shop.singhelectronics.ca/ground-shaker-32hz212b-black-12-dual-competition-32hz-ported-sub-box/
https://www.hifisoundconnection.com/Harmony-Audio-HA-BV2X12E-Dual-12-Empty-Vented-Port-Sub-Box-Unloaded-Enclosure-HA-BV2X12E
https://www.down4soundshop.com/down4sound-pro-fab-v2-2-12-2-12-sub-box-dual-12-inch-kerf-port-subwoofer-enclosure-box/

I just got a JL Audio 12W6v2-D4 subwoofer from a friend. I need an amp that will go well with it. I've been looking at theses:

• Kicker 46CXA8001 - $189.95
• Down4Sound JP8 - $169.99
• S1-850.1 S - $134.97
• JD500/1 - $279.99 (I also found a used one on market place for $150.00

Looking for the best bang for buck option that will pair well with this sub. Do you guys have any suggestions?
Thanks!

JL Audio 10W0v3-4 or SUNDOWN AUDIO SML 10 for a 2020 Silverado 1500 crew
Believe the JL only comes in 4ohm (at least this price) where the sml has more options. Price is what I'm looking for (less than $200) and these seem reliable performers
Wanting 2 to likely going to be paired with a JP8
If you have another <$200 recommendation. Let me know
https://www.down4soundshop.com/sundown-audio-sml-10-shallow-subwoofer-d2-500w-rms-2-ohm/
https://www.sonicelectronix.com/item-39835-JL-Audio-10W0v3-4.html

Hey guys, I currently have two Skar VXF 12 D2s powered by a Sundown SIA 3500 I'm looking to get a new amplifier that can give these guys plenty of power because I know they can move more than they do now.
I'm on a bit of a budget and I know Sundown has a good reputation so the SFB 8000D sounds like a good amp to get as a replacement, especially since it can produce around 6200W at 2 ohms. I watched a few videos saying that they are monsters and are good for what they are/the price.
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I currently have a 425a alternator and a 0 gauge ofc power cable going to the amp from the battery, and will be upgrading the alternator cable, adding a battery in the trunk, and will run 2 0 gauge AWG cables from the second battery to the amp as well as ground for the amp and battery. So supplying the SFB 8000 with the power it needs shouldn't be an issue.
Also, will 300 amp fuses be enough for the power cables? (Specifically the two power cables that will go from the rear battery to the amp)
I haven't found any other amps in this price range with enough power while also being reliable, any recommendations or input is appreciated, thank you.
Edit: I am looking into building a custom box to give the subs more breathability.

Built a box and have the terminal cup from down4sound linked below. I’ve never seen a cup like this with bolts and washers. How do I use it? Do I need a ring terminal for each side under the washer and put the bolt thru the ring terminals? It seems weird no matter how I think of doing it the wire will never be making a connection, it thru would always be separated by washethe plastic terminal cup.
https://www.down4soundshop.com/down4sound-1-channel-terminal-cup-grade-8/

https://www.down4soundshop.com/down4sound-pro-fab-birch-flat-pack-2-15-2-15-sub-box-diy-dual-15-inch-ported-subwoofer-enclosure-box/
Sundown recommends 3 cubes of air space per box and tuned at 35 hz. WIll be running them on 1800rms until I have the funds to upgrade my electrical and get get 3krms amp. going in a 2016 grand cherokee. Anyone ever try one of these glue and screw it boxes?

I just installed a starter setup that needs upgrading, already. Been running it one week. I need more power and bass.
1) How far can you push a 10" Rockford dvc P3.2 past its 500 watt RMS without destroying it. 2) I have two 500 rms P3'S sharing a 1000rms infinity amp. The amps power wire is 4 awg. Haven't done a big three upgrade. Is it possible to milk more watts out of this setup or push them with a 1500 RMS amp? 3) Can I push 3000 watts with an extra battery and no alternator upgrade? 4) Are down4sound amps good quality?
https://www.down4soundshop.com/down4sound-jp23-v1-5-2300w-rms-amplifie
Thanks.

Looking at this and my know-it-all friend who fried new subs by setting his gain too high, by ear, said if i get that I should buy an audiophile apmn-1500 to replace the jp8. The jp8 pushes 1256w at 1ohm and the apmn pushes 1414W at 1ohm. How does the quality of these two compare? How well do these deal with heat? I have my current cheap amp in trunk in area that gets very hot and want to keep the new amp there. How much louder will a 158w difference make? Im sure the sundown can take the 1414. Recommendation? If i should go with the AP (or other) then i wont buy the package and will buy separate cuz why pay for amp ill not use?

Alright guys. I wanna plan out a huge build.. for a compact car. No I don’t want a Tahoe or Escalade build.
I have a fully 100% dampened ‘21 Kia Soul. I managed to fit 252sqft of StingerX dampener in there. Roof and doors have multiple layers and literally everywhere else has it too.
I Currently have the largest alternator I can get my hands on for this car, 345a. I’ve looked into a dual alternator setup but I just can’t find anyone who would be able to make that happen. So that’s what I’m working with. I also have 2 powerxs agm batteries rn. I get a solid 14.8v.
I have an X15v3 D2 in a 5cu box powered by an sfb5k, but I need more :). I also have some mids and highs running off 200rms per channel. When I go balls out I get voltage drop to 13.6v.
Here’s what I’m thinking. I could do 2, 3, or 4 of that same sundown X15v3 sub which are $700 each. I already have 1. I’d want 3k of useable power per sub.
First thing is how to arrange them? Should I do 2-4 in a wall facing the driver maybe 9”-12” behind the seat? like thisOr should I do those open type 6th order boxes where the subs are inverted with magnets facing the ceiling on the inside of a huge box that opens to the driver like this one
Second thing would be amps. My sfb5k is absolutely solid. I also over wired it tho with multiple grounds. If I went with 2 subs needing 6k I’d consider maybe the sfb8k. I don’t know anything about taramps 8k but that’s a cheaper option. Or the JP83 which is .5 ohm stable. I’d also consider the salt 8 but that seems like an expensive version of the jp.
If I got 3 subs needing 9k I’d want 12k which I could use the taramps 12k .5 ohm stable or maybe 2 of the jp63. I don’t want to go with the salt12 unless I have to since it’s so big and expensive.
For 4 subs needing 12k total I figured I’d run 16k to have the headroom. Would 2 sfb8k be a bad option if I kept them at 1 ohm? That’s only like $1,100 for both. Or 2 of the jp83 would be around $3k.
And finally Since I know 345a isn’t nearly enough I would need a lithium bank. I don’t know hardly anything about lithium quantities, I just know that for short bursts it can make up for not enough alternator. I would demo full blast for more than 15-30s tops. I heard 80ah of lithium but I don’t know for sure if that’s enough or if I’d want double that.
Budget is negotiable. Under $7k is ideal but it can go as high as 10k. I’d build the box inside the cab myself so that’s not really part of the budget. Budget just needs to be subs, amps, and lithium.
Also any alternate suggestions to what I have listed? Thank you to everyone who replies.
Also I would love to take it to competitions but I consider this more of an extreme hobby vehicle.

4/27/2023 Update:

I wanted to update this thread as I think I may have found my issue. As it turns out CarPlay does not play all audio sources with the same volume. SoundCloud is my main music source and I noticed that on Apple Music the tunes absolutely slapped when cranked up. When playing the same track through SoundCloud, there was a noticeable volume loss. To test this theory I used the Bluetooth function of the radio instead, to my surprise the SoundCloud tracks were substantially louder.
I may just use Bluetooth from here on out as I can't stand the lower volume of 3rd party apps via CarPlay. With SoundCloud being one of the smaller apps, they don't have a native CarPlay app unfortunately.
Happy bassin'!

Original Post:
Hey everyone, I am hoping to get some insight on my issue as I am no expert and often miss obvious things during troubleshooting.
The issue is that my new setup doesn't outperform my previous setup, possibly a bit less.
Current setup:

• 2008 Mazdaspeed3 w/ 110A OEM alternator
• Costco Group 35 battery
• Eonon R51 Headunit
• Down4Sound Profab Box sold with SA-12 Classics
• Down4Sound JP23 Amplifier @ 1ohm
• Down4Sound 0 gauge tinned OFC cable

Only because this is my only comparison, my other setup going 5+ years strong:

• 2006 Mazda3 w/ 90A OEM alternator
• Costco Group 35 battery
• 0 gauge big 3
• Kenwood DDX470
• Ported eBay box, dual 10s, pretty big
• Sundown SA-10 Rev 1 (The 600RMS rated ones)
• Hifonics BXX2000.1D @ 1ohm
• KnuKonceptz 0 gauge KCA cable

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Before I continue, I want to preface that I know the Speed3 is missing the big 3 upgrade, it's on the list and is upcoming. Mazdas are finicky with HO alternators, requiring external regulators, so I'm trying to keep it similar to my Mazda3 setup by just staying OEM, maybe another battery down the line.
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I finished the install on my Speed3 and was a bit disappointed it wasn't louder than the SA-10s in my Mazda3, so I started doing some troubleshooting to figure out why this might be.

• Subwoofers are DVC 4ohm wired down to 1ohm, confirmed at the terminals on the box
• Headunit clips at 23 out of 30, with loudness on. I like this enabled, everything else is flat
  • Loudness off, headunit doesn't clip at 30, subwoofer volume remains the same after tuning
• JP23 amplifier tuned via headunit at vol 23, 40Hz 0dB tone until clipping, then backed off a bit
• I have a 150A fuse under the hood close to the battery
• Sub RCA out 0.16v-0.17v on each
  • Rear speaker out 1.9v on each
  • Either output, tuning the amplifier to just before clipping yields identical volume
• LPF on JP23 set to right around middle, where I suspect ~100Hz is (25Hz-250Hz pot)
• Subsonic filter set to right around middle, where I suspect ~30Hz is (10Hz-50Hz pot)

I'm likely missing some stuff, but am just looking for advice on what to check for, what I missed, etc. For all I know the radio could be shit enough to cause this entire thing, I'm really unsure.

Looking to do a new setup with a single DC Audio 12" level 3, dual 2 ohm. (https://www.down4soundshop.com/Level-3-12-m3-D2/)
Would this amp be a solid choice for it? https://www.down4soundshop.com/sundown-audio-sia-1250-1250w-rms-amplifie
Or possibly this: https://www.sonicelectronix.com/item-158923-NVX-VAD27001.html
I'm still running stock electrical system.
Thanks.

Looking for a pre-wired box to put in, I was wondering if this kit is decent quality? I’ve heard good things about sundown but I’m not sure about the amp https://www.down4soundshop.com/sundown-e12-bass-package-2-e12-12-inch-subs-ported-box-jp8-amp-1000w-rms/

Currently running an 07 MDX w/ nav born stock except for a single kicker comp r 12 powered by a ds18 1800.1. It feels like it’s lacking and I just want a little more power but also on a highschool budget. I’ve heard good things and have decided on a few things but would like some honest feedback or recommendations. I’m no audiophile but I do like my ball shaking bass, but also nice sounding.
For the sub/enclosure I found this Sundown deal on D4S link
Sundown SFB 1000.1 amp on eBay link
And then a 4 guage wiring kit from skar link
And all this totals to around $650 which is what I’m trying to get to. There’s also another combo with the sub/amp/wiring but no box here but I need a box and am having issue finding a good one for the sub. So all in all I come to you guys to seek guidance. Is it good as is? Or should I go for something completely different, or is an upgrade even worth it. Trying to stay $650 or less so please let me know. Thank you guys!

I am upgrading my system in my 2016 Honda Accord and trying to decide on an SQL sub. I am aiming on upgrading to a single 15" sub. I am trying to decide between the Stereo Integrity SQL series vs. IDMAX V4 vs Sundown SA V2. I have heard good things about all 3 and am struggling to come to a decision. What is everyone's thoughts on these? Alternatively, if you have a better SQL focused sub in mind that isn't one of these. I'd also like to know. I know that I will likely need to upgrade my amp to pair better with these subs. As for budget, something in the realm of the Subs below would be ideal.
Links:
Stereo Integrity SQL:http://www.imagedynamicsusa.net/idmax
IDMAX: https://www.woofersetc.com/c-23-subwoofers/c-35-15-subwoofers/p-11706-idmax15-v4-d2-image-dynamics-15-dual-2-ohm-idmax-v4-series-subwoofer.html
Sundown: https://www.down4soundshop.com/sundown-audio-sa-v2-15-subwoofer-1000w-rms-dvc-2-ohm/
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Current System: Front: Hertz MPK 165P.3 Rear Deck: Hertz MPX 165.3 Trunk: 2 Pioneer TS-W304R 12" subs in a Prefab Vented enclosure tuned to 36Hz. Amps: Zapco ST-4XP for the front and rear deck speakers. Kicker CX600.1 for the subs. Processor: Helix DSP.3

I upgraded my 4channel amp a while ago (6 months) and now the old one is just sitting here. It’s the sundown sfb line. I upgraded the 200.4 to a 500.4.
The sfb200.4 puts out 75w @4ohm. I paid around $275 for it, Figured I’d sell it for $150+ shipping. here’s the link for it
Edit: I don’t support Facebook so fbmarketplace isn’t for me