[Adjusting Gain on Amp]

ok I have a pioneer avh p4200dvd hu, I usually set it by ear, this was my first time trying the dmm method, just curious to why its not recommended to use the bass boost, last time I had my amp gain set about halfway and about a quarter of bass boost and that worked out pretty well for me, I will check around for an oscope

[Adjusting Gain on Amp]

my hu was set at 75%, and I had the subsonic at 15Hz just because that is its lowest setting, I changed it once I was done, and telling me the dmm ftl does not answer my question

[Adjusting Gain on Amp]

Ok I have a Hifonics Bxi 2006D. I attempting to set the gains with a DMM. Well I will be running the amp at 1 ohm @ 2000w. So using that formula I got 44.72v so I used a 50Hz test tone from real of excursion, with my low bass set at around 75 or so and bass boost set at 0 and my subsonic set to 15HZ. Well if you look at my gain knob the far left is 9v and the far right is 0.2v. So Im assuming 0.2v is wide open. Well when I used my DMM to achieve the 44.72v my gain know is basically at 3 o'clock which is at about 75%. And my hu has 4v preouts. Just curious does this seem right.

[Accessory Key Position]

sorry guys i just went out to double check and sure enough it was one

[Accessory Key Position]

your truck does have an acc. pos. on the key cylinder just about all cars have an acc wire even the 08 bodystyles.... take down your panel near your knees it has 2 7mm bolts at the bottom then there will be a metal loop looking thing that covers the actuall colum and keycylinder wires thatr has 4 10mm bolts take those out then find the THICK BROWN wire thats your 2nd acc wire that will work with the car on acc it wont do the rap shutdown with the key off and whatnot but it works like a regular car off that wire

So you are saying that there is an acc wire, but there is no acc position to actually turn the key too, my switch has 3 positions, off, on, run most cars have 4 positions which are the same except with an acc position.

[Accessory Key Position]

your yellows your constant, your reds the switched the grey is where you tie in

so where you connect your power to power (constant) you hook up another wire and extend that to your toggle switch then from the toggle switch you wanna go out to your red switched on the deck

hope the picture helps

picture was very helpful thanks

[Accessory Key Position]

I also have another solution for you.. You wanted to use it only when in the accessory position, so I'm taking uhoh's idea, you could also get a test light and find which wire in your ignition is your accessory ( + ) and hook a toggle up to that to run your head unit. Uhoh's idea is the best, but the only problem is when you forget to turn it off, you can drain your battery. My buddy wired his up the same way, and his head unit is possessed and turns on whenever so it drains his battery often. Also, might want to fuse your toggle somewhat near your 12v connection so if it shorts, only the fuse blows and no fires happen.

Just my .02 cents. Feel free to use my advice or not.

Edited for spelling. Typing to quick.

my model Tahoe doesnt have an accessory position

[Accessory Key Position]

i splice a wire in from my constant to a toggle switch out to my switched so i can turn it on when i want and off when i dont want it on

thanks, but to make sure that I am following you, can you do like a quick sketch

[Accessory Key Position]

(dont have said vehicle) but i like to run a toggle switch for my deck hooked up to the switched so i can turn it on/off whenever i want

so u have the switched power source hooked up normal, and then u run a constant hot to the same wire but just leave it off until needed??

[Accessory Key Position]

For those with aftermarket hu and speakers that are not using any harnesses. I know the RAP powers things for like 10 mins but you lose that without the proper harnesses. So I was wondering how do you guys/gals play your a/v system with the key off since these trucks dont have an acc key position.

[Anyone see a problem with this port?????????????]

port are looks a little small to be honest

the area is on the smaller side but im sure it will be fine, well winisd says it should lol

[Anyone see a problem with this port?????????????]

so you all think this will give better results

[Anyone see a problem with this port?????????????]

it will be 4 subs total, two 12s per side, there are two center walls missing in that pic, but it will be two enclosures

[Anyone see a problem with this port?????????????]

Please explain to me why this will not sound good or how i can fix this if it is a problem

trying to tune my box to 33-34Hz, its 3"h x 14"w x and 14"l thru the middle

[Port Length]

i ddnt get much out of your original post...

but i believe winsd says port should be 15" it should be 15" total in length... Including the baffle or whatever layers that affect the total lenght of the port..

here is an example...the front is the double baffle side...

in this case... you would have to cut the "port piece" to 13.5inches.. becuse the front is double baffle...

edit: btw this is a side view... hope it helps...

thanks, that is exactly what I was asking, and my pic was just an example of how the port opening would looking from a frontal view

[Port Length]

ok can i get some actual help

[Port Length]

if you subtracted the .75 from the external dims of the box them yes that is correct

i must have confused you or something, I am wanting to know how long should the port physically be

[Port Length]

Im using winisd to calculate my port length. Now lets say it says my port length should be 15" and my box is 30" deep. And my port sits in the middle of the box on the bottom, using the bottom board as a part of the port, lets say 4"h x 12"w. Would I cut the port piece 15", 17" or 13"????

[Help, Need A Custom Box for a TAHOE]

do you know how to fiberglass??

[my box design and specs]

i had my 2-12" cvxs at 4.5 cubes internal

[Best Setup]

the less port area you have, the easier it is to tune low. BUUUT you run the risk of having port noise which is super annoying and sounds like balls.

the more port area you have (always aim for 12-16sqin per cubic foot), its a little harder to tune lower but the performance is better as far as moving air around.

do you use this rule for the gross volume or the net volume

[Best Setup]

the less port area you have, the easier it is to tune low. BUUUT you run the risk of having port noise which is super annoying and sounds like balls.

the more port area you have (always aim for 12-16sqin per cubic foot), its a little harder to tune lower but the performance is better as far as moving air around.

how is it harder to tune?

[Best Setup]

???

[Best Setup]

5.5-6ft3 @ 34hz w/ 70-80in^2 of port area per pair of woofers is my box suggestion.

how does the port area affect the system, bc u can still tune the box wit a lower port area

[Best Setup]

Then halve those numbers and build 2 of them

And in short, no.

Changing 32hz to 38hz you can hear but 32 to 35 you would struggle with. It's kinda personal preference. Build the port on the large side, you can always choke it later if you need to.

how exactly do you choke the port, like can u give me an example