imhungnurnot

help please..

First off, can I count on port end correction to lower the tuning freq of my enclosure? For example, NET Vol. = 2.6 cuft. or 4493 cuin. Port: 12.5" wide x 3.375" high X 24" long without end correction, (port length = 24") tuning = 38.58Hz with end correction, (port length = 25.6875") tuning = 37.52Hz I know 1Hz difference in tuning isn't really audible (but the end correction factor will differ in different situations i.e. port height, etc), but I want to know if the end correction factor actually exists!!!! Secondly, I'm about to build a box for one DD 9512g. DD recommends 42 in^2 port area with 22 port length with 2.6 cuft NET vol. which yields 39.97 Hz tuning frequency or 38.79 Hz w/ end correction (using 12.5" wide x 3.375" high).. This tuning seems pretty high.. I listen to rap/rock so I would like the sub stage to be able to play over a fairly wide range of frequencies having okay output on the higher freq. but still get pretty loud on the lower freq. Personally.. I was thinking 36 Hz counting end correction so that would mean the physical port length should be about 26.625" So what should I tune to using 2.6 cuft NET Vol. and a 12.5" wide x 3.375" high slot port?

So there must be some type of conversion to determine xmax?

what is a epicenter? i've heard of this when graphing ellipses in high school.. but nothing related to car audio

DD post their excursions in "suspension". Does this mean the total distance the sub can travel as opposed to xmax which means the greatest travel in one direction? For example, their 9500 series has suspension of 80mm... it doesn't seem like this can be xmax.. so would the xmax be 40mm ??(half of the total distance traveled)

I see! So if i wire up the subs to .5 ohms.. it wont go below that.. but I can measure the difference of impedance with a ohm meter playing differnt frequencies to see how much of the time it is close to .5 ohms.. if it doesn't hover around .5 ohms for too many frequencies than it should be fine, especially with the sundown! Thanks! Great post!

Oh okay, i see!

Ah! Thanks, that is a good way to isolate the problem!

Okay, thats what I was wondering.. People were telling me that their box's made a 4x or 3x affect on the impedance, but I know it fluctuates. Think they were talking about on average?

A guy on here broke a few records with a ridiculous amount of port area just with two tens. I think if you have about 20-24 sqinch per cube tuned reasonably high maybe 37-39 Hz it'll do well.. but this is only my option.. I don't have very much experience with SPL. So we'll see what everyone else has to say about my info

How can one calculate the box rise and how does the shape of the box, etc. affect box rise? I am interested because I want to wire my subs down to .5 ohms, and I hear that it probably wont be an issue because of "box rise."

So I used my truck today but when I turned started it I looked at the amps. Well they both started off in protect mode like all amps do, then the bass amp went to green then back to protect very quickly. I have more investigating to do with the volt meter, but do you think something is possibly wrong with my amp?

Well I never thought to check the voltage because the starter spun the motor over quickly on start up. No lag whatsoever. But I did just install some bucket seats, and I wired the power to the back of my bass amp.. I disconnect the power seat so now im waiting a few days to go check it out.. This may be the problem.

Its the DD 9512g, thermal limits? who cares.. lol i know what VC smells like when you get it hot, just turn down the volume.. Just because an amp on each sub I don't need to have 1000 watts on each coil.. gains are adjustable.. and I think it'll sound cleaner running both amps at 2 ohms anyway... plus i already have the amps from awhile back. why not use them? Also, how can one calculate the box rise and how does the shape of the box, etc. affect box rise?

its a DD (digital designs) 9512.. why would the sub matter?

I did it just for you.. I figured you would be the man for the job to test the rig.. I'll even give you a deal on the sub so you can mount it in your bedroom so your wife can get some real pleasure!

I have a Dual 2 ohm sub 1500 wRMS.. so it can be wired at 1 ohm or 4 ohms. I have two 1 ohm stable Autotek 1400s.. They can be linked using the MXL-100 but then I can only put a 2 ohm load on the "strapped" amp set up.. so if I run the sub on the strapped setup at with the sub at 4 ohms ill only be getting 1400 watts. Which is what I would get if I run a single amp on the sub at . Think I could run a amp to each coil if I set the outputs of the amps with a DMM? Would this cause problems? Thus giving me 1000 watts per coil and 2000 watts for the sub all together..

Will do!! Thanks for the feedback on the post! lol

Why not post it in both? Yes, I DO have a big truck with a dildo strapped to my BTL that you can sit on.. im thinkin 25Hz test tone will work nicely

Interested in a used SAZ 1500D in good condition. PM or email ([email protected]).

so how much will it deliver at .5 ohms?

I thought if you half the ohm load you'll gain about 3/4s of what you were already getting? ex 1500+(1500*3/4)=2625

I know this has probably been answered before, but the search bar is pretty much useless on this forum. So if I can keep my electrical system from dropping below 13.0-13.5 volts, how will the saz take the .5 ohm load?

Try using your eyes to read the original post...