Hello every one I'm new to this forum but not new to to the car audio game, just curious to learn what I can to get better. Thanks for having me and I will be looking forward to learning new things from whoever is willing to speak about it.
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Hello every one I'm new to this forum but not new to to the car audio game, just curious to learn what I can to get better. Thanks for having me and I will be looking forward to learning new things from whoever is willing to speak about it.
:welcome:
There's no such thing as an "audio wannabe" IMO.
You've got some experience, you've got some preferences, you hear something and like it better than something else... you have goals...
Welcome! and enjoy!
Welcome to the best mobile audio forum on the interweb!!!
Your very right, well said.....I think that I'm getting everything dialed in then I hear Somebody else's system and it makes me realize maybe I'm just a wanna be......LOL. I do have a pretty good equipment I'm just having a hard time getting it dialed in properly because I don't have the right equipment to do that......just going by ear
Welcome!
What do you want to learn so you can stop being a wannabe and start being a ... be.
Well where to start....lol have any good ideas for a good sound quality shallow mount sub? The JL13 Tw5 is a great sub but I'm really trying to avoid the big price tag.....looking for other options. By the time I purchase subs ,wood for the Box , vinyl coverings, beauty panel wood ,and fasteners it's a little out of my budget
The least expensive one I've spent time with is the Rockford Prime shallow subs like the R2SD2-12. They sound pretty good and they are really affordable.
I am also a little biased because I work at Rockford : )
In my opinion, subs are the stereotypical "starting point" for every car audio person, because:Quote:
Originally Posted by Mattjsmith
- If you want to add drama and/or depth to the music, whether you are a basshead or SQ guy, it's "what to add". It's also what's probably most OBVIOUSLY lacking most, in your factory system.
- Something that's true in car AND home audio, it's a single thing you can add, and dramatically transform your sound experience.
- It's a thing that has somewhat of it's own science, or at least is a simpler entry point into the science - since the wavelengths are larger than your listening space and that makes it much less complex to calculate.
- It's the most DIY-accessible thing you can learn, with the greatest tolerance for imperfection or even mistakes, and still have it at least "be OK".
Download something like WinISD, I think that's still an easy and free subwoofer enclosure calculator. I'm sure there's apps these days that you can download onto your phone too. What this software does is show you how a subwoofer will perform, in different enclosure types, and sizes. You really only need these Thielle-Small parameters to get started...
...and bear in mind as you look for these in the subwoofer specs, this general rule of thumb really is true - if there's no T/S specs, it's probably a crap brand, crap sub, aimed at people who wouldn't know what to do with T/S specs if they did measure them. If there's ONLY these specs below, then it's probably still a cheap sub that you want to take the specs with a grain of salt. If there's a bunch of other T/S specs BESIDES the ones below, it's likely to be a reputable brand aiming their product at audiophiles who understand what all that Greek actually means. As a newbie though, these are really all that should matter to you for now:
- Qts - Besides being one of the big ones that any software needs, in general if it's a number about 0.6 or higher, that's a sub made for sealed boxes. If it's a number .4 or lower, that's a sub made for vented boxes. If it's in between, it's probably "OK at least" in either type, but the flip side is - maybe not IDEAL in either, also.
- Vas - Besides being another of the big ones that any software needs, in general that's proportional to how large of an enclosure you'll need. It's impacted by the other specs, and in reality it just measures what volume of trapped air is equivalent to the spring factor of the subwoofer's suspension - but a tiny Vas is usually an indicator of a "small box sub", and a large Vas is an indicator of a sub that's not made for small boxes. Bear in mind that while "small box" sounds like something you'd ALWAYS want to engineer into a subwoofer, there's physics behind why that's not possible - the smaller of a box you put a sub into (regardless of how it's engineered to try to balance other variables), the less efficient it is (less loud per watt), and the more difficult it is to play low frequencies with that subwoofer (a function of excursion - which naturally increases twofold, every octave lower that the subwoofer tries to play... and FYI "an octave" happens every doubling of frequency, so 20hz-40hz is one octave and 40hz to 80hz is the next - and really is the same thing as an octave in music).
- Fs - Besides being one of the "must have" variables for any software, it's the natural resonance of the subwoofer - where it's most efficient, at least when NOT in a box. And of course, you need a box... and the box changes that resonant point... but the gist is, the lower the Fs of the subwoofer, the easier it will be to create an enclosure that plays low.
- Xmax - I'm adding this one, it's not usually a requirement in all software, but it is very meaningful in setting your expectations for the subwoofer. As a spec, crap companies might lie about it, so it's also one you have to be careful about. Cheap companies use "peak to peak" excursion, which basically doubles the industry-standard one-way excursion number, to make it seem doubly impressive as it actually is. Even crappier companies use a measurement all the way to where the subwoofer bottoms out and breaks itself, which is WAY out there past "how far the motor can push the sub before high distortion sets in". So, it's a reason you want to shop reputable companies - because it tells you a LOT about the actual capability of the subwoofer. Meaning:
If you were to do a sealed box, and compared one subwoofer with 7mm of Xmax to one with 14mm of Xmax, and designed your enclosure so that your amplifier could actually push the subs to those excursion levels (side point: software CAN tell you how much excursion your sub will reach in a given enclosure, under a given amount of power - it's one of the things more advanced subwoofer enclosure designers factor into their design, to get everything out of the subwoofer that it's capable of giving), the 14mm subwoofer would be twice as loud as the sub with the 7mm Xmax. Also - because of that frequency/excursion relationship I mentioned earlier, it means the 14mm subwoofer will be able to play lower than the 7mm subwoofer, at a given volume level.
And, like I said in the parenthesized side-point, you do want to use your software to make sure you are getting everything out of your subwoofer that you can.- RMS Power Limit (rating) - Also not a "software requirement", but there's two ways to "blow" any speaker: The first is "over-excursion". You build a big box, your subwoofer gets amazingly loud, it's super-efficient - but you crank it up and the amp drives the sub PAST that Xmax, PAST the Xmech (the mechanical limit), and your voice coil former smashes itself many times per second against the back plate, creating a mushed copper spaghetti spiral that you absolutely want to shut off before the voice coil windings short circuit your amplifier and take THAT with it also. You don't want that. But the second way to "blow" a speaker is to send it more power than it can thermally dissipate. In that scenario, the glue holding the voice coil melts, basically, and the voice coil turns into copper spaghetti that way inside the magnetic field, even if you are nowhere NEAR the physical excursion limits with that much power - like, if you build a super tiny box and buy a huge class D amp to power it - it's easy. Same thing - really easy to have that copper spaghetti coil short circuit, and (because of "Ohms Law"), basically present a dead short to your amp and blow the amp too. So - it's a high-risk thing, it's a number you want to know, and model in your software, as well as not buying an amp that sends too much power to the subwoofer.
- Subwoofer displacement - how much physical space the sub takes up inside the box. This doesn't count as airspace in the box, in fact it eats it up. So, a smaller sub leaves you with more usable airspace, and a huge monster sub leaves you with less. It's important because you HAVE to account for it in your sub box design, or you won't get what you model up in the software.
- Port displacement - this one isn't on the spec sheet of the subwoofer, it's part of your design. Again, the whole port (air inside the port and all!) doesn't count as airspace in the box - it has to be subtracted out. Doesn't matter if you use a slot vent, or a simple round PVC vent - subtract it out. Of course, if you have a sealed box, it's a non-issue.
The place to START, believe it or not, is with your CAR.
Measure the space you want to use, and then subtract 1.5" from each dimension. Why?
Because you'll probably use 3/4" MDF to build the box (it's strong, it's stiff, and has great damping properties), and you should buy that in 3/4" thickness. And because it's the airspace INSIDE the box that the sub sees.
The top + bottom panels of the box at 3/4" thick each, so inside the box, it's 1.5" less than your vertical measurement.
The front + back panels of the box are also 3/4" thick each, so inside the box, it's 1.5" less than your front-to-back measurement.
And your sides of course also each take up 3/4" each, so inside the box it's 1.5" less than your side-to-side measurement.
The general best practice is to give the sub as much space as you can - that will make it more efficient, requiring less power... will make it play lower as well. You'll see when you start modeling things up on-screen.
But the reality is, you only have so much space you'll be willing to give up - so, being a critical limiting factor - you want to START HERE. How much space are you willing to give the sub?
Measure height, measure width, measure depth - subtract 1.5" from each measurement, and multiply those together. That will be "cubic inches" so divide by 1728 to give you "cubic feet" which is most commonly talked about for airspace.
And it's the most important thing you'll need, in any software, to show you how the subs (that you haven't shopped for yet!) will compare.
This is really maximum enclosure volume, and of course it's even a bit unrealistically big, because you haven't yet subtracted out "sub displacement", or (if applicable) "port displacement". You'll need to do that on a case by case basis, as you compare.
Now you can start looking for subs! For sure, start with Justin's recommendation - Prime is RF's most budget-friendly line, and often those shallow subs are NOT ideal in small enclosures, but sounds like the one Justin is suggesting might just be! You absolutely will see, when you model them up!
I like browsing with Google Sheets or Excel open, with those specs on the side and each sub I'm shopping for in a column, like this:
Specs Subwoofer A Subwoofer B Subwoofer C Qts Vas Fs Xmax RMS Power Sub Displacement Price because that's important too!
Now that you've collected specs, open up your software.
Most all of them have a way to enter sub specs, and save them as "a subwoofer" that you can then subsequently open up in the software, and play with. So start there, enter them and save them.
Then, open them up in the software and model them up - the cool thing with most software is you can model up one sub, in one particular box, then model it up in a different size or type of box, and see both curves on the screen, for how they will sound. You can then click to the "excursion" plot and see how the two compare with 1 watt (usually there's a place to put in "power", and I use the RMS power rating at this point, since I wouldn't feed MORE than that into the sub). Make sure it doesn't cross much higher than the Xmax - but you want it at least close to the Xmax or you aren't getting everything you can out of the sub (that's for sealed boxes... for vented it's a little more complex since the vent WILL minimize excursion somewhere - but it still does play a role).
Then - once you've picked a favorite enclosure type for your sub candidates above (having factored in the various displacements you need), you can start comparing "sub A in my favorite enclosure" to "sub B in my favorite enclosure" and picking which sub actually fits YOUR car, and YOUR enclosure you are willing to build. There WILL be a winner.
Finally, you know what you can shop for now?
An amplifier! Because now you will absolutely know how much power you will need - for THAT subwoofer you picked, for THAT enclosure you picked. It'll be no MORE than the RMS rating of the sub (so you don't blow it thermally), and it'll possibly even be LESS than the RMS rating of the sub if you did make a generously sized enclosure, such that the sub doesn't NEED the RMS power to reach it's full excursion.
And if you do this - you'll feel pretty accomplished, and you WILL have the post impressive subwoofer possible, for your goals, for the space you are willing to give up - and the results of that are always impressive. :cool: