Hi everybody new guy here looking for advice but willing to help when I can

[Brad Pettijohn]

Hi there I just joined because I recently installed my first system and when I got it metered it did better than I thought and the guy thought I'd do pretty good at a SPL comp coming up so now I need help advice so I can hopefully increase my SPL.

So what I've got is a Pioneer DEH-7800MP+Alpine SWR 1243D+Kenwood KAC-7204 amp+Power Acoustik 2 farad cap. I've got it installed in a vented box that I made myself which is about 2.2 cubic feet tuned to 33htz and its wired with 6gauge wire with inline fuse. I built this to be a bumpin system but I want good sound quality otherwise I'd have tuned the box higher. It does have the sound quality I want but I got curious of how much SPL I had after somebody I work with thought his was louder so I showed him mine he no longer talks **** and actually told me about a local comp he thought I should check out.

Anyways I went down to the place that holds this comp to get it tested out of curiosity the other day and I hit 137.0 with windows up and 150.0 at the port. I knew it had to be decent when he said holy f*** when he was metering the port. He complimented my box and said 150 at the port is pretty good considering he had 4 15s and hit 156. I was happy to hear that from a pro installer and he told me they had a comp on June 17th and I'd do good under the small cone area category and would probably place top 3. I didn't really plan on entering comps I was more looking more for SQ but now it sounds like a good idea.

I'm pretty sure I can hit higher with some adjustments on my amp's bass boost which is fixed at 50 htz or by changing some of the EQ settings on my deck. From what I've heard 80htz is where you usually hit higher SPL numbers but I'm wondering if that varies with different subs. My EQ has 16 bands 5 are bass freqs 20-31.5-50-80-125. I have the 20htz down as low as it can cuz my sub isn't responsive under 23htz. With my box tuned to 33htz I'm thinking maybe I should turn the 31.5htz down a little too since from what I understand hitting lower freqs than your tune freq is can damage your sub. I have the LPF set to 160htz I'm thinking I should go lower to like 125 or 100. I know I need to adjust my settings on my amp or sub or maybe both but I'd like to know the best way to do that to get higher numbers without distorting it should I adjust both sub and amp or one or the other more?

I think I have a pretty good idea of what to do but I'm not totally sure and if I'm wrong about something I'd like to know so I can correct it. I was also thinking of putting polyfill in there will that help SPL or hurt it? I'm thinking it probably won't hurt it but I'm somewhat new to this so any advice would be appreciated.

I know getting a better amp would be the best way to help me with this but I don't know if I'll be able to afford it right now so if you can help me work with what I have the best I can thats what I'm looking to do for now. Any feedback would be greatly appreciated I think I detailed everything pretty good but if I left anything out that you need to know let me know. Thanks for your time hope you guys can help...

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[Bettr n' Revrse 5,000+ posts]

That's probably about it for that setup but try little things...

 

[outsideshot23 10+ year member]

That's probably about it for that setup but try little things...

you read it all?? lol.. i just read the title... welcome

 

[Bettr n' Revrse 5,000+ posts]

Hahaha ya I can read pretty fast and can skim even faster...

 

[LosIsATool 5,000+ posts]

Whats the vehicle?

 

[LosIsATool 5,000+ posts]

OP, i just noticed something in your post..

Take that cap off of your system! you do not need it for the power you are pulling. you could run that set up in a yaris and not need that cap. All it is doing is cause a slow death to your alternator, And its a power accustic product.. Get rid of it

 

[subzero 5,000+ posts]

you need to do a sweep and see what the vehical peaks at. Then you need to decide how low you want to go. My car peaks at 47, but I love low bass. So, What I have done is designed a box that was tuned to 26.5 and loved that, but it didnt hit hard easily. so I changed the tunning to 34hz and that was much more well rounded. You have to decide if you want to get higher #'s or be more sq. If you want both, then your going to have to really understand your subs potential. Also trying different box styles might change the feel of the music. The polyfil idea is probably going to give you more headaches than you want. Calabrating the port and tunning with polyfil *****. It is easier to get higher numbers at higher tunning generally, but then you almost completely loose the daily listening enjoyment. Start with the sweep. then have the shop to a model to see what box works best and find the right subs Good luck.

 

[the727kid 10+ year member]

Paragraphs please.

 

[audioholic 5,000+ posts]

OP, i just noticed something in your post.. Take that cap off of your system! you do not need it for the power you are pulling. you could run that set up in a yaris and not need that cap. All it is doing is cause a slow death to your alternator, And its a power accustic product.. Get rid of it

Im not sure why you say a capacitor will cause a slow death for an alternator.Using an over-time average, the only energy a capacitor uses is what is lost to resistance in the circuit. If you want to worry about killing your alternator, the actual amplifier and speakers will 'kill' your alt much faster, since they consume power energy the alt makes, which forces the alt to work that much harder.

The internal resistance in a cap can render it ineffective at benefiting the circuit, which is often times a valid argument against buying a cap. But to say its dangerous to your alt and should be removed isn't realistic. I generally agree caps aren't worth buying, but if he's already purchased the cap, it isn't really hurting much to keep it. That is assuming its a simple 1-farad or less cap. Some of those larger ones can have a fairly significant IR.

 

[jtomsic 5,000+ posts]

Im not sure why you say a capacitor will cause a slow death for an alternator.Using an over-time average, the only energy a capacitor uses is what is lost to resistance in the circuit. If you want to worry about killing your alternator, the actual amplifier and speakers will 'kill' your alt much faster, since they consume power energy the alt makes, which forces the alt to work that much harder.
The internal resistance in a cap can render it ineffective at benefiting the circuit, which is often times a valid argument against buying a cap. But to say its dangerous to your alt and should be removed isn't realistic. I generally agree caps aren't worth buying, but if he's already purchased the cap, it isn't really hurting much to keep it. That is assuming its a simple 1-farad or less cap. Some of those larger ones can have a fairly significant IR.

yeah ive never heard of a cap killin an alt either.. ive pretty much just heard they are usueless and serve no real purpose..not even as a band-aid for your electrical system..

 

[AlterEgo99 5,000+ posts]

Welcome to Hell.

Holy fuck dude! Write much!?