cubdenno

What if you measured impedance rise through out the entire frequency range that you would play the sub and it is above 4 ohms? could you then run a 2 ohm dcr subwoofer on the amp?

Thanks!! He has been driving it around since his basketball tourney go over. Showing all his buds. I have gotten 4 calls from his friends on helping them build a box for their cars. It's amazing what Jacob has in these little woofers. Of course only in autosound is 8 inches considered small... I keep finding myself amazed at what these things do.

If you are going for sound quality, the design I have runs fairly flat from 30 to 75. There is audible 20 hertz output but because of the tuning frequency of the compound port and the amplification power used,I have the subsonic filter set to just under 30 hertz. if you were going to run less power than 200 watts than the subsonic would not be needed.

Give it gobs of port area and go a bit bigger than recommended and you will get some serious extension and an increase in efficiency

Oh yeah. He even said that yesterday. I see you have changed your system a bit. how do you like the HAT's? I need to swing over to Indiana and give yours a listen.

He was already a basshead. I think it's the age. yes the Sundown 8's hit like a hammer. We chose them for shock factor as in "THOSE are 8's doing that???!!!" The hatchback does help but I gotta really give credit to the box designs of Pete Kulicki. He can really do a lot with some exotic enclosures. Of course this box is giant but for some reason the boy was willing to give up space to have increased loudness...

Here is a couple vids Video 1 Video 2

HOLY chit!! Four 8 inch subs plus a thousand watts give or take... Hits hard. Can Feel the air move. I am uploading the videos right now to photobucket. Gain is at the minimum. Zero bass boost. Am very happy with the end results! Unfortunately, the boy got rammy with stuffing the box in and peeled a bit of the mdf. will fix that when we paint the box. The boy did learn that taking accurate measurements and then giving yourself a bit of breathing room is important. On the bright side, the box is gonna be a bitch to get out. So theft deterent system built in.

Sorry, unfamiliar with what CA glue is? It's a long explanation, I'll let Wikipedia take care of it http://en.wikipedia.org/wiki/Cyanoacrylate My bad.. Superglue...

These are the rebuild from Mike. Wasn't worried about it just wanted to fix it so we can get this box playing. It models incredibly well and should hit in the 140ish range give or take 3db. Which isn't bad on a 1000 watts. At least as far as our calculations go.

Sorry, unfamiliar with what CA glue is?

Jacob or whomever can answer, The dustcap came off one of the E8's my boy is using. What glue should be used to fix it? How long should it dry? As an added note, the box for my boy is finally built. Going to paint it this spring but he is going to use it untill then. It has been hooked up @ 4 ohms for a couple of weeks. We are going to hook it up @ 1 ohm today. I am going to video his first impressions of it.

My 1500 is powering a TC Sounds TC3000 15". Just a little update. I wired the woofers for a 16 ohm load on the SAE 1000D. In his car it was loud. About as loud as when he had 3 MTX 10's at 4 ohm. I made him run this way for the weekend as his box is not sealed because we are waiting on terminal cups to be delivered STILL. Tuesday I wired it at 4 ohms. He put on some DJ Unk. When the first bass notes hit, his face lit up. Talk about a huge smile. He has been showing his friends how even at 4 ohms his stereo is as loud as theirs and in some cases louder in the box that "he helped build." Hopefully this weekend we will get this thing done. Jacob, these thing really hit amazingly hard. Very detailed and musical even in a big ol ported box. And I do mean big. I am going to get it wired in when done and video him the first time he listens to it for a reaction.

Any amount of the port can be in the box or out of it. It will change the available volume you have for your woofer. The more port in the box you have, the less volume available and vice versa. My question is that with the Nightshade being a fairly high displacement woofer, is a 4" port going to cut it? I am still learning about the whole port sizing business. I would figure that with the power you are going to be running with that 12, the port you want would be noisy as hell. Just a question on port sizing. I read somewhere that for high power applications and high displacement woofers using 12-16 sq. inches of port area per cubic foot of volume should be the rule of thumb. Please you SPL guru's chime in!!!

I look at it as a tool like the EQ.Most of the SQ winners use T/A. Gain adjustment only goes so far for super accurate staging. Again I believe in installing the speakers to achieve as close as possible equal path lengths but of course I can't.

Bigjon, Active is not that bad nor is it that tweak intensive.Unless you want it to be. Plus I have found in LOUD SOUND QUALITY it allows the best sound because you CAN tweak every aspect. I am running full active and love it. I have the Alpine H701 which is a dream to deal with so not sure about the Pioneer. Just make sure you set your crossovers correctly for the drivers so that you don't blow them. The only thing missing from the passive network is any notch filters that have been factored in on the passive's driver selections. You can always EQ those in. I have found that with very little eq I love the way mine sounds. Mine is not set up for any SQ comps but I can always do that. I like to equalize pathlengths of the individual speakers as much as possible so that T/A is not needed as much but again not sure about your Pioneer.

Well, it's Saturday morning and we had a productive night. We got the port painted. The baffle cut and the T nuts set. Well not all of the T nuts. The dad pulled a brain fart and did not buy enough T nuts or 10-24 bolts to mount the woofs. So we have 4 per woof. Also Parts Express only sent 1 terminal cup. So we did not seal anything up regarding the baffle. Just half ass screwed it down and took the beast of a box in the house and hooked it up to the HT subwoofer amp. Wired at 16 ohms... Wow. Its an old Polk Audio 100 watt @ 8ohms 150 watts @ 4. We wired it to 4 ohms and it rocks the house. It really blends in with the rest of the system. gonna watch the new batman on it today. The boy painted the Sundown Emblem on the box in art class.

Only about 4 hours from you. Good summer weekend project!!

Sorry cell phone camera:

Yeah it is pretty sweet. On a side note, I just finished the last two boards for the ports. just got to put the port brace in and finish the top/cut the holes for the speakers gonna let the glue dry.. This thing is freakin huge!! For 8" woofs that is. My boy painted Sundown on the top/baffle in art class. I will post the pic later with the rest of the pics of the box. Thinking about painting the port path of the box. Any benefits? or should I not bother?

Thanks!

Thanks man!!! I am as anxious as he is to hear it. But purposely taking my time so we don't screw things up. Pete does some fantastic designs.

Well due to my busy schedule we had not done much on his system. We were going to order a box from Mr. Marv, but due to a glitch in his grades and his lack of funds for a box and shipping, I decided to do a father and son project. We ordered a box design from Pete and have commenced to building one together. Slow going because i travel during the week and he has basketball practice and he works 16 hours on weekends (I am a hard ass about teenagers working) AND I expect him to be involved and learn something it is taking more than a couple of hours. But here are some pics of what we have accomplished. We should have it done by next weekend. The speakers: The design: The start: The dad (me) cutting it out: The puzzle to put together: The boy laying it out: The layout: Screwing it together for fit: Mostly together: Gluing together now: Slowly coming together:

That is something I can do. The test I did was at 50 hertz set up on repeat. I let it do about 25 or 30 passes. Every time it was 52 and 17.4 or really close to those that it didn't matter. Now I can do the 20 -60 hertz sweeps no problem. And my equipment is in fact true RMS. On the initial sweep when I ran the 20-80 hertz, What I found was the variation of impedance. I understand what you were explaining, and I knew that "X" ohm speaker is not really that resistance when music is applied. But if you know the lowest resistance your amp is going to see in the band of frequencies it is going to play, does that info allow you to factor that as the true impedance the amp will see? And lets say that the dcr is .25 ohms but the actual resistance with signal is 1.1 ohms as the lowest, is that going to smoke the amp with daily use? Or are amp manufacturers figuring this impedance rise (sorry I know you don't like that word.) to get the minimum impedance for the amps? ex: 4 4ohm speakers parallel for 1 ohm dcr with rise 3.5 ohms real world. (I just pulled these numbers out of the air)

That is better than Cool. Impressive, awesome, kickass comes to mind. Plus this is from a stock Toyota electrical system. Stock battery and 80 amp alt.