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blue fury

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Posts posted by blue fury

  3. Posted

    Just reread my post about origin of the vocals, I didn't mean actually in front of the steering wheel, I meant directional-wise. If I were to guess a point were the vocals seem to originate, it would be about a foot or 2 outside the windshield in line with the steering wheel and my eyes.

    Anyway, here's what's next.

    littlex.jpg

    xconbox.jpg

    2 12" Xcons in a ported box tuned to 31hz designed by Mobeious.

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  4. Posted · Edited by blue fury

    Wait, I was told this a long time ago:

    "Slopes in a crossover don't add together for a final amount. If they're both 12db, it's a 12db slope. If one is 12 and one is 24, then you have a 24 db slope, rendering the 12db useless. "

    This isn't true? I never really could understand how what I quoted to be true since my logic told me exactly what you posted above, Impious.

    Completely false. Don't know who told you that, but it's completely untrue.

    Thanks for confirming it. I didn't do a direct quote becuase it's on a different forum. .

    So in a nutshell for basic situations, the xover slope is summed together.

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  5. Posted

    Wait, I was told this a long time ago:

    "Slopes in a crossover don't add together for a final amount. If they're both 12db, it's a 12db slope. If one is 12 and one is 24, then you have a 24 db slope, rendering the 12db useless. "

    This isn't true? I never really could understand how what I quoted to be true since my logic told me exactly what you posted above, Impious.

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  8. Posted

    A few days ago, I won a pack of damplifier Pro on here. I finally found some time to do a little bit today. Took me about 2 hours just to do this!!

    PIC-0484.jpg

    PIC-0485.jpg

    PIC-0486.jpg

    PIC-0487.jpg

    I'm going to use more than half for the doors from this pack, then the rest on some trunk areas. Possibly Wednesday is when I'll have a chunk of free time before finals week.

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  13. Posted

    MB Quart DSC4125 $180 sonicelctronix

    ummmm NO, OP please don't even look at this amp, it is OK, but wal-mart compared to arc and sundown, steg...

    now it seems you need to think about the future....the arc or the 100.4d would be plenty for those speakers even unbridged. and either could run them actively which actually can be safer for your tweeter since passives are generally only 12db/slope, and both those amps have 24 db/slope which will help keep tweeters from playing too low. most ppl blow tweets on passive setups, not the woofer.

    if you don't plan on running any more mids/highs in future then go with the 125.2 no questions asked. if you plan on running others in the future then get the arc or the sundown, both are amazing amplifiers, arc is and has been quite proven in SQ competition. and any arc or sundown amp will push more than rated power even after normal voltage drop.

    as soon as i saw "sonicelctronix" i knew it was a no.

    i think its between the sax 125.2 or 100.4... only reason im considering a 100.4 is to possibly grow down the road.

    and im also most likely going with a 1500d or 2000d for a sub amp too match.

    Ive got one for sale, a local guy offered 275 for it but can't pay til next month. He turned down my offer to hold it for him so if you're interested, PM me.

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  17. Posted

    Thanks for all the help. I think the last question I have is this: Take a sub meant for music with say, 50hz for the FS in an appropriate sized box tuned to say, 33hz. As long as you don't give it enough power to bottom out, would it sound just the same as the same setup with the other sub having an FS of say, 25hz? These figures are just based on normal situations and not times where the super lows are desired.

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  18. Posted

    The bridge that recently failed in MN did not go into resonance. You are referring to the Tacoma Narrows which failed in the 40's. That failed not at its first resonance but a higher resonance excited by high air flow.

    Nothing will go "out of control" unless you force it to, but you should use your subsonic to prevent overexcursion or really know what you are doing and understand your source, levels, and listen for stress.

    Impedance rise is generally caused by a box response and not a driver in free air.

    The Tacoma Narrows. Thats the one I was thinking of. I could have sworn my professor said it was at its natural frequency, he's such a nice guy and was literally a rocket scientist with a Ph. D. in that field as well as Mechanical Engineering iirc. I'll have to ask him about that again.

    The FS usually is below the playing frequency right? If you were to apply a decrease in level say, -9db (random figure, not a slope but just a decrease) on all the frequencies there and below to prevent over excursion, would the sub be able to play all the frequencies below? I hate to use 'what if' situations because of the unlikelihood that I'll actually do it.

    More importantly, is there any other reason than over excursion not to have the sub play at or below its FS?

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  19. Posted

    My first question is, why do you think a speaker would be damaged by playing at it's Fs?

    Well... I never specifically read it but I just took the natural frequency idea and used it with some info picked up from various places- basically I was given the idea that it it's frequency and with the continuous power, the soft parts would go out of control. I supported this thought with that bridge that failed a while ago. The wind caused it to sway and swing at its natural frequency until its supports couldn't resist the force from how far it was swinging. The bridge obviously collapsed so I thought that this is along the same lines- the FS after a short time would cause the mass on the soft parts to vibrate beyond what was safe and eventually lead to some sort of failure.

    I apologize if I sound stupid, but it's never been explained to me. :(

    The woofer doesn't self-destruct at Fs. Think of a weight at the end of a spring, with the spring being suspended vertically and the weight attached at the bottom of the spring. If you grab the weight, pull it down and then release it, the spring will rebound and continue oscillating up and down at a specific rate. In speaker terms, the mass of the soft parts would be the weight and the suspension would be the spring. At some specific frequency, the weight of the moving mass will be in balance with the compliance of the suspension and there will be a natural oscillation of the "weight on the spring" (the moving mass on the suspension). This is the Fs, and can be identified by a peak in the driver's impedance.

    Impedance rise right? I have VERY little understanding of this so I'll try to look for good articles on this. Know any?

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  20. Posted

    All objects have natural frequencies. This includes your whole body or any of your parts. For instance your stomach, ever wonder why you get sea sick? You excite the natural frequency of your stomach and your body doesn't like it.

    Subs of course also do. The lower generically means that they will be able to play with authority lower, but in a box designed with some savvy you can get a sub to play well below its Fs. It just isn't as easy as it is with subs with a lower Fs. If you don't understand the whole gamut of T/S parameters though, I would encourage you to follow manufacturers suggested box sizes and not arbitrarily design your own.

    The bolded line is what I'm asking about. I know the idea and definition of natural frequencies but I don't know how a sub behaves when playing frequencies very close to the FS. EXAMPLE: a sub with FS of 35hz in a box tuned to 28hz (random figures) playing music. There has to be 35hz notes played at some time or another, right? That said, I don't understand how a sub could be in this situation and not be damaged.

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  21. Posted

    I guess I don't know much about this subject. I did a quick search on here and didn't find all the info I was looking for on the questions that I've had lately. To my understanding, it's just the natural frequency of the sub. I'd like to know a little more than that.

    Recently I saw a topic where some 8's with ~38hz FS were for sale and someone described them to play really low on music, how nice they are for music, on and on. I didn't know if these subs were meant to play lower than 38 hz or if those people just called +38hz 'low'. Correct me if I'm wrong, but the FS is 1 frequency and not including the + and - frequencies (to some small extent) meaning that the sub can play above and below the FS. So if the box that these 8's are in is tuned much lower than 38hz with no high pass above it, wouldn't these subs be playing 38hz pretty frequently? Why doesn't this damage them?

    I guess I just want to know what you can and can't do with the sub in terms of box tuning and playing music while knowing the FS. I'm not really satisfied with how I worded the paragraph above so maybe it can be better explained though back and forth conversation.

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  22. Posted

    1. Post your SSA user name

    Blue Fury

    2. State that you qualify to the terms and agree to follow through with them as they are written above.

    I qualify to the terms and agree to follow through with them as they are written above.

    3. Post a description of your car and system

    I have a 1996 Chevy Lumina LS. All the electrical has been upgraded with an EA 200A alt, Optima D34/78 Yellow Top in front and 2 Northstar NSB 90's in the back. All the wiring between the alt and batteries as well as the big 3 is 4/0g. The HU is a Pioneer 880PRS. 4 way active setup with Vifa D26NC55, Tang Band W4-1720 powered by a Sundown 100.4, Hertz HV200 powered by a Sundown 125.2, and a Rockford Fosgate RFR3110 powered by a Sundown 3000D in a 6th order bandpass. RCAs and speaker wire is from Knukonceptz. I currently have no deadening.

    As soon as I can afford it, the 100.4 and 125.2 will be replaced by a 6 channel amp to save space. Then I'm going to replace my one 10" RF hx2 sub with two 12" SSA Xcons.

    4. Post how you plan on helping promote second skin including the other web site you will post your build log in. (Rembmer build logs and videos are always better for us)

    The installation of this will be added to my current build logs and a new one just for the second skin forum. Plus I'll talk big about it to people that either don't have any deadening or have inferior deadening haha

    5. You must tell us something about yourself that nobody on this forum knows about you

    I consider 'Van Wilder' plan an accelerated education compared to my plan.

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  23. Posted

    I can see some of the points that mrd is trying to make and even agree with a couple, but in the big scheme of things like M5 said,

    Low budget screams install, amp, and speakers.

    Not one time did I come across anyone with a low budget that wanted excellent SQ.. just loudness.

    I'll I've read here is mostly different mindsets from loud to strictly SQ.

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