SINTORMAN

gotta have tact with these kinds of posts so people actually think about it. I let loose on fb with Tony though lol

(I am not very active on here but I am on **** and I shared this to SSA at the request of Denim) First off, I want to be clear about one thing. I'm not here to hate on SMD tools. However I am here to help people utilize cheaper and sometimes better equipment suited for the job as well as other jobs. So let's begin with the dd-1. I'm sure most of you know the main competitor to this an oscilloscope. But you might not know why. The SMD dd-1 is 149.99A Velleman HPS140I oscilliscope is 120$ (from Amazon) Here are three ways that the oscope stands alone from the dd-1. The dd-1 does not account for voltage drop. Let's say you set your gain with the dd-1 at 14.4 volts. Now you apply a real load and your voltage is in the 13s or lower. Now your top clean voltage has been lowered as the rails sag. So when you turn it all the way up to the max clean voltage you are now clipping since your voltage has dropped. An oscope can measure clipping in real time with a real load. So you will know even at lower voltages if you are or aren't clipping. The dd-1 can only measure at two different frequencies; 40hz and 1khz. Now this might not be a big deal to some but it's fairly limited. An oscope can measure at any frequency that your audio system will reproduce. This also means you don't have to change your filters to accommodate the dd-1 and then switch them back. The dd-1 can't account for rail sag due to impedance. In most class D amps the rails can put out a higher clean voltage at higher impedances. Hence why you see higher ohm ratings being higher than half of the power of the next lowest ohm rating. IE. An amp doing 2000 watts at 1 ohm but 1100 at 2 ohms. So if you are wiring low and you are rising to around 1 ohm then your rails are going to have their top end voltage cut vs no load on the amplifier. This however can be observed with an oscope in real time. The dd-1 is a 1 use tool. That means that it is only suited for one thing. However an oscope can be used for many different tasks even outside of the audio industry. Plus if you ever want to try and fix your amplifier you will need an oscope. As you can see from those reasons alone an oscope is not only better suited for gain setting, it is cheaper and is capable of handling other tasks as well. Next the CC-1. A lot of people don't know that you can do every function the cc-1 has with a cheap DMM. The CC-1 is again 149.99$A DMM can be as cheap as 10$ (for this use it's not important to have a fancy DMM.) Now basically what we have here is a device that has a voltage comparing circuit. So you set it to remember a certain voltage and then if it's reading higher than it will illuminate the corresponding led and if it's reading lower then it will illuminate the corresponding led. When you hit the right voltage the middle light will light up. I'm not going to delve into different kinds of filters as some have the same slope but a different level at the crossover frequency itself. Some are -3db and some are -6db down. But for the purpose of this we are going to assume 3db. So let's take a 24db slope filter for example. If you want to set a high pass filter at 80hz then you need to open the filter all the way up. Measure the output voltage with a dmm at a level you know is not clipping. Then plug your voltage into the input voltage and select -3db on the level change and solve for output voltage. This calculator is pretty nifty: dB calculator for amplification gain and damping (loss) factor of an audio amplifier calculation decibel dB ratio - sengpielaudio Sengpiel Berlin So at 60 volts, if you are -3db down at the crossover point you are looking for 42.47 volts. Now play the tone you want your cutoff filter to be at. A common one is 80hz for mids. Now play 80hz with your filter wide open. So then you just keep turning the filter up until you hit that voltage. Congrats your high pass filter is set. For low pass filters you do the same thing but set it wide open in the opposite direction. Now lets say you need to gain match two amplifiers. (you want to do this before filters). Open your filters wide open on both amps. Set the first amp's gain using a scope, dd-1, dmm or whatever. Now play 60hz and measure the voltage on the set amp. Now just turn up the voltage on the second amp until it matches the first one. (you don't need a load for this). If you want to match the xover settings to the first amp that has the xovers already set then all you need to is grab a tone above your low pass and below your high pass. For your high pass play the tone that is below like 20hz and measure the voltage on the first amp then slowly turn up the high pass on the second amp until the voltage is the same. For the low pass play a tone like 100hz and then turn down the filter until the voltage on the second amp matches the first amp. To confirm your amps match properly just double check by playing a tone below, one not filtered and above. The output from both amps should be the same at all three frequencies. Sure it takes a little more math and effort to use a dmm but at the cost of over 100 bucks difference I think it's well worth it. Not to mention a quality dmm can be used for WAY more things than the cc-1 can. Now onto the IM-SG Honestly it's a pretty nifty tool. However if you have a laptop I recommend a woofer tester 2 instead. IM-SG is 299.99$WT2 is 159.95$ At 140$ cheaper it can do everything the IM-SG can do and actually is easier to pull TSPs from. The one thing that is great about the IM-SG is the portability. So again... no laptop; get the IM-SG... yes laptop; get the woofer tester 2. And finally the AMM-1 I gotta admit on this one that it is a pretty cool tool for the casual basshead trying to learn more about his setup. The best thing it's got going for it is the hall effect sensor built in so power factor isn't an issue. But I'm going to put a AC/DC clamp, True RMS meter and Oscope up against it The AMM-1 is 359.99 on preorder right now. I believe it will be 400 ish full priceThe hps140I scope is 119.99$The Craftsmen 82369 is 59.99$A Fluke 113 is 116.96$Total: 297$ The one area the AMM-1 has a good clamp setup beat is that it knows the power factor and thus can determine actual watts being sent to the loudspeaker. However as of now this isn't very useful information if you consider where we are. 99% of amplifier clamps are done with a DMM and clamp meter. So when people see the lower power they are going to wonder why it's lower than what other people have clamped. Yes in a perfect world we should all be clamping for watts. But in an industry dominated by Voltamp clamps then the true watt figure is somewhat unnecessary as of now. Another issue is that it will stop reading upon clipping in the amp dyno. Which for competing doesn't make it any more useful than a couple of clamps when you start clipping. And 99% of people competing allow a soft clip for more power. Not to mention unless everyone is using the amm-1 at the comp then the division of power won't be fair. In this situation a video camera really helps with both methods as you can record the power and go back over it to find peak power at peak spl. Another issue is that the amm-1 can't calculate amplifier efficiency since it doesn't have a DC clamp onboard. Granted this isn't that big of a deal but amp clamps are much better with efficiency figures as well. But with a proper clamp setup you can do this as well as clamp your alternator to see if that is doing rated power. A plus for the AMM-1 is that it does all the math for you. But it really isn't that complex of math so you be the judge how much of a plus this is. The rest of the things the AMM-1 can do can also be done with the clamp setup I listed. So I didn't feel they needed to be mentioned. So I guess if knowing true power is that important to you then the AMM-1 is your tool. If you are fine with the current industry standard then the clamp setup is for you. All together now. If you have the complete SMD toolbox that costs 960$ as of right now. If you grab the clamp setup and the woofer tester that costs you $457 Less than half the cost and the only thing you can't do is find true power/phase angle. However you can do a lot more with the second option for less than half the cost. The choice is yours :thumbsup:

Definitely seems like something was wrong with the sub from day one.

Can you edit the first post to state exactly how one would sign up and such to go the event? I really want to go but I have never gone before and I would like info on it and any tips. Thanks,

I've been thinking I and guess I will go sealed just because it fits my situation better. The measurements are H:24.5" W:36" D1:18.5" D2:11.5". So a wedge then it probably won't matter where it's mounted. k Kool thanks for all the help.

I've been thinking I and guess I will go sealed just because it fits my situation better. The measurements are H:24.5" W:36" D1:18.5" D2:11.5". So a wedge

Since I caught you, can you offer any advice from my questions in post #15

I thought your name looked familar stefan. I have seen comments of yours at sundowns website.

So I guess I will do 18" sealed because I am fine and prefer a flat response with my music. So I will shrink the sub enclosure to like 6-6.5 ft^3. And I was planning on putting the amp on the back of the enclosure behind the back seat where there is plenty of room and best of all not visible from the outside. So high qts, what about the cooling, p chamfer, Spider, and I heat ring? Should I get all of those upgrades? Plus sealed will give the sub a little more breathing room to reduce massive vibrations on the back hatch. Anything else I should know when making the enclosure? PS: I was also planning on bolting the enclosure to the frame but have like 1 inch thick rubber spacers to reduce vibrating between direct contact of frame to enclosure. Is this a good idea? PSS: Should I mount the sub directly in the middle of the surface or near the bottom where its the deepest?

Well I believe the phrase go big or go home applies. 1. only a bit more money so why not. 2. looks 3. Why not? Generally more cone area = more output, but putting a big driver in a small box will have negative effects compared to a step down in size driver in the proper enclosure. Just because a sand rail is fast, doesn't mean it'll work best for rock crawling (bad analogy I know) I think I will be fine considering the recommended ported volume is 6-10 ft^3 and I am close to the middle.

These are pictures of my car with cardboard templates of the sides of the box. http://picasaweb.google.com/116170605906548217544/NewSubwoofer?feat=directlink The "sub" box in there right now will definitely not be in there when I get the 18.

Well I believe the phrase go big or go home applies. 1. only a bit more money so why not. 2. looks 3. Why not?

Well I believe the phrase go big or go home applies. 1. only a bit more money so why not. 2. looks 3. Why not?

Thank you for the warm welcome! I do want to go ported but I am concerned about two things. The sub side of the box will be 4 inches away from the plastic of the hatch. I know this is going to cause even more rattling but will it make the sound any different? Two: Is the website I listed a good source for porting? I put in the fi recommended stats into the formula and I got almost the same results.

INFORMATION: I own a 2002 pt cruiser. I am going to soon be buying a Fi Q18 and a AQ1200D for my car. I have calculated maximum external volume that the enclosure can be and it is around 8ft^3. I will upload some pictures tomorrow but its dark outside so I can't go take any pics. Two Options: 1. Sealed. Would allow me to downsize the box a bit to around 6ft^3 and give the sub some more breathing room. 2. Ported. I would keep the volume at the max and port it to 28hz like recommended. My only concern is that the space between the Q18 and the rear hatch is 4 inches. I know this will affect the sound but I don't think it will be too big of a problem. So what should I pick? Is ported all that louder? Will it matter with an 18 at around 1000-1300 watts? Does Sealed have that much more SQ? -Sound Quality is very important to me. I want to be able to feel clear punches and not just buzzing unless thats the way the song is. -I listen to rap/techno/dubstep/alternative, pretty much everything with bass. -The sub cannot be pointed towards the front or up only back! -I am currently using http://www.clubknowledge.com/Car_Audio_FAQ/?t16 to calculate port size/length. Is this an accurate formula/information? -I am not changing my selection in Sub or Amp and I would appreciate it if only the questions listed are answered. -Thats great if you have suggestions for how I do things but this post is really only for the above questions. Thank you for helping me out!!! I will make sure to post pics tomorrow. PS: I am sort of unclear on what the different options do when purchasing a fi subwoofer. Which items should i select? or should I get all of them?