Advanced Discussion

I wanted to ask this question because I understand about them through extensive physics classes, but I wanted to ask on a clearer run down on how to deal with them in the car audio world say for example a normal SQL for the everyday street beater and then the SQ competitor and then wackos like me who are building massive boxes to stupid loud numbers (I understand the flow and movement of the air as controlled by the box designer, in my box case dave edwards is the genious behind it, but I wanted to start this for all members)

Do any of you notice how if you look at rims on a car rolling down that street while playing a song with a high frequency that you can actually see the individual spokes almost like its slowed down. Its a trippy effect. Sometimes people rims will also look like there jumping up and down on some bass notes. I also get this similar effect when i play a 50 hz and up frequency while looking at led lights ( xmas lights, BMW spoiler Brake lights) these lights also move to the bass..It is an awesome effect very entertaining! I was wondering what is causing this and does anyone else experience this?? I think it has something to do with our eyes moving at the same frequency as whi…

Both 12V batteries. but is mixing them going to cause a conflict at all?

Here is a test we did a few years back... Always surprises people... http://forum.carstereos.org/clipping-test-...41.html?t=47441 -Mike

I'm confused as to how a subwoofer can have a Resonant Frequency of say 18 hz, but a frequency response that only goes down to 25 hz. If the sub only responds to 25 hz, how can you know the fs is lower than that. The new Soundstream T5's are an example of this. I just don't understand. -C

I'm looking for anyone near Sioux Falls with a Term Lab. I won't be going back to Dashboard by Karl's, so I'll need to travel.

Alright. I've got to get this perfect. I'm LOVING the Bravox CS60K's. The output, mid-bass authority, and overall quality of sound is fantastic. They're truly a great set for the price I paid. The problem I'm running into with them is very common with speakers/components in their price range however and that is either beaming or break-up. Not sure exactly what the difference is just yet, though I do have a pretty good idea, but somewhere in the 4k area it's almost ear piercing on CERTAIN songs. It seems some of the songs have a lot of material in that range 2-5k that just causes them to nearly make your ears bleed, or so it feels. Then other songs couldn't be smoo…

I've been doing a lot of thinking and pondering how to get the sound stage and imaging in my Jimmy even better. The thought of tossing the components for an 8 or 10" midbass and some full rangers in custom pods has crossed my mind many times, along with rebuilding the door installations with something that puts the aiming pointing right where it should and going with an active setup consisting of a 7" midbass and a large format tweeter. The latter brought me to a though as to exactly what constitutes on or off axis. Is on axis just directly aimed, or is there a few degrees of leeway there that can allow a person some wiggle room before it's considered off axis? As it …

Hey guyz, I know that different cones have differents advantages and drawbacks: - strength - lightness - ease of use But what I am wondering is what kind of "sound" (metallic, warm, etc...) do those have - subwoofer cones by the way. For example, hemp, kevlar, aluminum, titanium, threated paper, and so on... Thanks Kelvin

This isn't exactly a question I have, but here goes. My friend is a big physics geek and on the topic of speakers, he asked why we don't have cooling devices to keep operating temperatures low so resistance is more predictable, and less influential. I Don't really know how to answer him, could some of you throw me some ideas why it isn't a practical idea? My only thoughts on it are practicality regarding a mobile environment and the equipment needed, as well as cost. But why don't filhy rich folks use woofer coolers to take advantage of their amps? I'm interested to see what gets said here It seems cool in theory (no pun intended) Just really impractical.

I am looking to use my laptop in cars to do RTA measurements and perhaps FFT later on as i play around with things. From what i have been reading the phantom power is required for many of these XLR connections. I have seen some battery operated flat response mics but the price jumps quite a bit. i am intending to buy the trueRTA application and perhaps the LEAP software or some derivative there of. I am looking for some guidance on what microphone and accompaning hardware is needed to accomplish this. am i able to use my onboard sound card or should i buy a USB card with higher performance. anyone ever used a PC for this type of work and have a…

Ok to start this thread off. Please do NOT post information you read from the internet where the original writer could of pulled out there ass. Just don't do it. Facts only here please. No He said she said bullshit. To get started, I was reading and come across some info. No need to get into what it was, but it lead me to really find the truth about wiring. I think there is so much bullshit being passed around as the truth its not funny anymore. WeLl I finally want to inform people of what's really being advertised, and how to draw a conclusion from that. Ok so you have 4 major types of wire talked about in the audio world. OFC Silver Tinned OFC Copper Tinned OFC CCA Bas…

I am curious, alot of infinity subs and solobarics and such call for a pretty small ported enclosure volume (less than 1.5 cuft for a 10) If a sub has a recommended enclosure volume for a vented box of 1 cuft, what would happen if you put that sub in a 1.75 cuft enclosure?

So Im tryin to come up with a design for my 18's and im stuck.. I can either have 122.5 inches of port at 5.5 cubes at 34hz or 70inches of port at 7.4 cubes at 28hz im leaning towards the 1st one or i can have even more space and just use aero ports thoughts?

i have a 1997 mercury mountaineer (ford explorer). does anyone know what the resonant frequency is of my truck. when i find the resonant frequency what will that acomplish? do i need to catch my 1/4 wave at the dash at the frequency? im not quite catching this theory.thanks for any and all help

I have a Soundstream Rubicon RUB1.2500D, and would like to either remove/disable the SSF circuit, or modify the SSF pot so that I can simply turn it off that way. I haven't looked at the resistance of the SSF pot yet, but could I change it out with a different value of pot to make it so that it is disabled at its lowest setting, instead of the standard 10-40 hertz? I have some experience in repairing and modifying amps, and power supplies and such, but I never have encountered something like this, yet.

I usually don't do this, and I hate to give this idiot more views but this was just to good. http://youtu.be/O2hraSZ55cE This is the first I've heard of this, and I didn't know you could see wiring move when current passes through it. I guess you learn something new everyday. This guy blocked me a while back for informing his XS Power batteries wasn't 6+ years old, as he stated.(Even though I don't know why he was making that excuse to begin with) so I can't comment to find out more on this wonderful knowledge he's giving out.

Now we will start with : Sealed enclosures : A SEALED enclosure will be the smallest,and is the simplest of enclosures and will have good low frequency extension, but might not have the best low frequency extension. If space is limited. and its a good choice for SQ fans (Sound Quality). PORTED enclosures (Bass Reflex) : A PORTED enclosure will generally have a better low frequency extension for a given response shape,but would require a larger enclosure. If you made the enclosure as small as the sealed enclosure, but ported it to gain the low frequency response, the output would deviate from the desired flat response. Ported enclosures are slightly more difficult to desi…

Just curious why no speaker manufacturer uses dual tweeter setups? I see multiple mids on a single speaker all the time, but I have never seen dual tweeters on a single speaker. What would be the cons and pros of using two tweeters per speaker (four total for stereo)?

ok..i've used the caluclators and figured out what the values are..but i have no idea on what to buy to achieve those values.. what i'm building.. a third order 18db octave @ 4ohm low pass passive x-over. the values for which are.. 7.9mH coil 441uF capacitor 2.65mH coil so, what do i need to achieve these values (other then the obvious..duh) i went to PE, and listed some stuff, but evidently it's incorrect. yeah, i'm being a touch lazy, but i need somone to list the part numbers and where they got them. i'd also like an explaination as to how they achieved those values (not the ones above, i'm still reading the12volt.com on that) but how they achieved getting the values i…

Bl/Mms is constantly turning up everywhere to describe the "acceleration factor" of a driver. This is totally wrong! The "acceleration factor" or "speed" of a driver is determined only by the bandwidth of the driver and nothing else. In reality the "fastest" driver or the one with the quickest rise time is one that can play the highest frequencies! Here we will use a picture to help explain the situation. In the following we show time from left to right, and amplitude from top to bottom. - Picture courtesy of Cool Edit 96 - www.syntrillium.com We have 3 complete sine wave cycles showing with a period of silence between each. The first one we shall say is 20hz, t…

http://www.hotrodders.com/forum/alternative-lizard-skin-103610.html Micro ballons http://www.heatshield-r20.com Anyone had experience with it? It looks interesting.

I'm going to be starting a 4th order blow through my rear deck soon and had a few questions. One being when I port through my rear deck would it be best to fallow to window angle to port straight up into it?

What exactly is the F3 of a speaker, and what should that number be relative to a ported box's tuning frequency, if at all? -C

i talked to a rep. at DC and he said i need 17inches of port area per cubic foot of airspace. how can i tell the port area of a round port? im going to be building 4, 4" in diameter ports, that will be tuned to 33HZ. the box is going to be 5cubes when its all done. i just dont know if i i will have enough port area to keep the port noise to a minimum. any help?