cubdenno

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.

I was able to measure my setup today. 52 volts 17.4 amps this was a 50 hertz tone 900ish watts to the sub is what I calculated. Wow. Guess I have a bit of head room... Jacob, this now makes me wonder when most manufacturers of amps rate their amps capability to drive low impedance loads, are they figuring in this rise in impedance into the overall picture? I was noticing a guy that was driving a .25 ohm speaker load that actually when the impedance rise was factored in was .95 ohms. This figured into my situation of an almost 4 times rise.

You bet! plus I hate having equipment and tools not being used. I love to tinker!! Plus this little exercise has shown me I went undersized on speakerwire to the sub!

Yeah I suppose. This whole thing got started with my kid. I have a few of the old Autosound 2000 tech briefs. There was discussion regarding Richard Clark GN. We were looking at what he said was needed to actually get the actual power rated out of an amp and how most amps could not actually do it. Which got me wondering what mine was actually putting out. Cause damn it pounds!!

Yeah, I am going to do just that. Any advise to see what the whole system pulls? Pink noise?

Well I grabbed the trusty fluke i410 digital clamp. Now measuring DC current, (And a thought just hit me, should I have put it on the negative?) I measured a max peak of 93 amps of draw at the battery playing a two step remix by DJ Unk. My boy had it in there. I measured AC current at the box at 19 amps.My two little ones were bugging me to come inside so I did not hook up another multimeter to check voltage. Now some things I did notice was that in my installation I am running 2 seperate runs of wire off the amp to each coil. These wires were warm and the banana plugs i use to connect the box were warm as well. I will upgrade the wire and redo the connections this weekend plus I will be able to do both voltage and current tests. All I can say is this combination of amp and sub puts out a ton of sound.

Yeah I believe it is termed 6th order though I always called it a dual relex bandpass. It's for a 16 year old kid. We were going to buy a box, but he wanted to build one with me. Stepdad/stepson bonding and all that. Plus I figure its a good learning experience. Figure when he gets tired of the sound we can always do a 2 cubed ported low. The output is high but really flat in its passband.

Ran a box design through WinISD and wanted some input. This is for 4 E8 8inch subs. It is a three chambered enclosure, each outside enclosure is 1 cubic foot tuned to 70 hertz. The inside enclosure is 2 cubic feet and is tuned to 40 hertz. The woofers will be mounted magnet end in the 1 cubic foot side two woofers per the 1 cubic foot side firing into the 2 cubic foot portion. This is for my kid who listens to mostly rap. Powering this will be a SAE1000d. A subsonic filter will be used to keep over excursion down. The graph on WinISD looks impressive in an open air environment. Any reason to not utilise this box design?

Fluke 87 multimeter. Measured at the box terminals and at the amp. Yes sub is in a box. I understand that the box "loads" the woofer or vice versa... Whatever the sub box combo becomes the load. Not that I am doing this as I don't have room but, does that mean I could do a two woofer combination, all thing being equal in my car, which wooferwise would be a .5 ohm load, but when in a box seeing music would be a minimum of about 1.55 ohms.

I understand that, but does that mean that it is possible to actually add a matching woofer to get a more closely realistic during music impedance? And heat may have been a minute factor but this was taken in the morning, 50 ish degrees and on cold equipment with about 30 percent volume. So am not concerned about the heat.

Not really sure what I am asking here but here goes. I am running a TC3000 15"DVC sub. Each coil is 2ohms. I am running this parallel to a SAZ1500d for a 1 ohm load. With no music this specs out at about a perfect 1 ohm at the box terminals. Now whem I measure resistance while music is playing using my trusty calibrated Fluke 87 DMM, The lowest I am seeing resistance-wise is above 3 ohms. It never gets below and of course we are not going to discuss the high point. This is all done on a 60-20 htz sweep. So one of my questions is, does this mean that my sub is at most only getting 500 ish watts? I suppose what I need to do next is measure voltage and current. Was just doing some testing with my son before we build his box. And had no way of explaining what was really happening. Any input would be great. As always, just trying to learn.

Jacob, I need a midbass amp. this looks like it could be the one. Sign me up!!

Well I made all of those mistakes buying stuff. Instant gratification generally costs more in the long run. Of course his appreciation goes up the more his friends want his stuff.

Also that box would take, according to the specs 1200 watts. I had 900 on it at one time. No issues

Nope. 4 of them

Thanks for the complement. The thing is @ 4 ohms it is absolutely killing! All his little buddies want to buy the subs!! Which he is going to sell to help pay me back for the 8's. I am excited about the 8's and 1000 watts!

I might get a refurbished SAZ-1500D and two Fi SSD 15s.. hows that then? Anybody know where to get the accordian gasket or boot or whatnot? I'm not sure where to find it, theres no RV suppliers in my city Can't praise enough about the amp. I bought one from Jacob used. It works flawlessly. The funny thing about subwoofers is even if you buy a cheaper model, you can always throw together a box and sell them to a teenager. As long as you haven't shredded them. But I agree with the consensus of buy as good as your budget will allow. Are you going to be competing with this system in the future? Because depending on that and what type of competition SPL SQ LSQ, that could better help you determine what to buy.

Are 8's out of the question? Maybe 4 Sundown E8's or 8 of them and an amp. Of course I have become partial to sundown. But you have the space for about any config you want with a truck and topper. Are you "blowing" in from a sliding rear window since you are not cutting?

Naw, the event I went to was in Danville Illinois. And yeah, it was nice to hang. For a strickly SPL event, I see area's I need to improve on. Especially a battery. Stock electrical and stock battery are just not cutting it. I am planning on getting with Chad from DIYMA and metering the overall sound Q of my car. Once I get that squared away, I may just try a SQ event. I am sure something is going on near me. I live in between Chicago, Indy, and Saint Louis. Of course I need to get my planars back and a new midbass amp (don't ask. Its the second one I have lost.) . And thanks for the Positive Reinforcement!!

Well I have most of my system in right now. Had to send my planar mid ranges back to good ol Parts Express so slapped together two little boxes with some quart 3 1/2's to play the mids in my system. Also blew my Fosgate 500a2 and swapped in an Orion 900.2 my boy was going to use (I bought him a refurbed SAE1000d from Db-r) So its been some ups and downs. I am running a Sundown SAZ1500D on a TC Sounds TC3000 15 DVC in a 3 1/2 cubic foot box @ 40 hertz. Here is the amp rack as I got it fitted in my car. Just for the record, am running a full active system with 8's in the door, my missing planar midranges and planar tweeters. Hope to do Sundown justice.

Well things went well at the show. Also this is the show where 2000LaDe took the overall. I scored a 143.5 and took 4th in my class missing third by .3 Db. The first place title in my class went to a Team Sundown member though so all is well in the world. Its my first competition in oh..... 17 years or so. A lot has changed. It was just, which one is louder. No real class differentiation other than number and size of woofers. It gave me something to try for next year. Most likely a burp box. Mine is tuned to 30 hertz. Should have kept the one tuned to 40. It had a higher bump in efficiency. I am happy that it went well.

I was there to see it. The car flat out rocked. Real nice guy as well. Great looking install.

I understand that a given sub in a given enclosure does not remain a "*" ohm speaker. The actual impedance is dependant on the frequencies being played. After watching the resistance dance around on my multimeter, I was wondering if there is a method to stabilize the impedance closer to what the woofer actually is and salvage some of that lost power from my amp.

What model?