10's or 8's...worried about low end.

[newusername 10+ year member]

actually, are you confusing Qts with Qtc? (btw, not being an ******* here, just trying to make sure we are using the same terms //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif )

Fc=(Qtc*Fs)/Qts if I remember correctly. That is what I was referring to.

im refering to the Q of the total system of the driver, including the motor and suspension. im not speaking in terms of anything in a closed box system. i can see how those parameters can yield you everything that you need to know, but it still seems to me like the Qts is going to be related to the Fs as a direct result of diaghram control.

If we assume that we are talking about the driver only, then no, Fs is not derived in anyway from Qts.

 

[hoss 5,000+ posts]

im not saying that it one is derived from the other, but that the two can be related to each other (in the sense that one is going to change as a result of changing the other.)

 

[newusername 10+ year member]

im not saying that it one is derived from the other, but that the two can be related to each other (in the sense that one is going to change as a result of changing the other.)

Can you describe how changing Qts will change Fs mathematically without attributing this to Mms or Cms? I don't see how one can be changed by the other if one is not derived from the other. //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

Again, the only factors in Fs are Mms and Cms. This is well covered in Thiele's original work and there must be 100 papers by now discussing these relationships. Hell, there is a page about it on Wikipedia.

What I think you are trying to describe are the decay, damping, and ringing effects around Fs that Qts, in part, describes, but in no way does this actually say anything about Fs. Fs only describes the frequency at which a driver resonates, which Qts has nothing to do with.

If you changed Qts by changing BL or Re (without changing Mms or Cms), you would not have changed Fs at all.

 

[audioholic 5,000+ posts]

Cot-an attempt to actually learn and a bit of humility on your part would go miles toward you getting a modicum of respect on here. Thinking that you are always right and then when confronted with a point on which you were totally off, coming back with "well that's so obvious that I didn't mention it" makes you look like even more of a know it all punk. You act like you have all the answers and sadly I think that you believe you do know everything. It is, however, amazingly apparent to the overwhelming majority of us that you don't know a **** thing and are incredibly insecure about your ignorance. As a defense mechanism you come up with these huge long winded explanations about how your utter drivel is correct to make yourself feel adequate. The real truth is that you are an insecure, ignorant little child that is coming to the stark realization that he is wrong more often than right and in an attempt to bolster his faltering sense of self worth, has to post these huge rants, not in an attempt to convince those of us that actually do know what we're talking about that you have a clue about anything and aren't totally out in left field, but rather to convince yourself that you really aren't an ignorant worthless POS. Having to lie to yourself is sad in its own right, but the saddest thing is that you've been telling yourself the same lie regarding your own adequacy for so long that it appears that you actually believe it even though you know it to be untrue. I hope I'm not around when you finally awake from your state of denial and get *****slapped by the reality of your pathetic existence.

While Im confident you wasted your time with Cot, I applaud your words. On the money.

 

[RedStangHappy 10+ year member]

I'm just curious through all the flaming of people......The original question is what goes lower 10's or 8's? And although we all know that 2 10's are not as loud as 4 8's , Isn't it impossible for 8" subs to go as low as 10" subs? If not could you post numbers, not dB's but Hz. Appreciate the responses, and before it starts I am truly a car audio newbie, not audio just car audio.

 

[Immacomputer 10+ year member]

I'm just curious through all the flaming of people......The original question is what goes lower 10's or 8's? And although we all know that 2 10's are not as loud as 4 8's , Isn't it impossible for 8" subs to go as low as 10" subs? If not could you post numbers, not dB's but Hz. Appreciate the responses, and before it starts I am truly a car audio newbie, not audio just car audio.

It is 100% based on the design of the driver. I know of some 18s that can't get as low as some 6.5s.

 

[Hintzyboy 5,000+ posts]

I'm just curious through all the flaming of people......The original question is what goes lower 10's or 8's? And although we all know that 2 10's are not as loud as 4 8's , Isn't it impossible for 8" subs to go as low as 10" subs? If not could you post numbers, not dB's but Hz. Appreciate the responses, and before it starts I am truly a car audio newbie, not audio just car audio.

No, it is nowhere near impossible. All things being equal (even though they never are) one ten will play low with more authority than one 8. But that is only because the ten is moving more air, and is therefore louder at all frequencies. This gives the illusion that the larger sub actually can play lower than the smaller driver. But if you add another 8, the pair will move more air and will therefore play lower louder than the single ten.

That is why a few people posted db numbers at given subbass frequencies. The amount of output the substage can give at lower frequencies is what gives the appearance of being able to play lower. Not the frequency response of the driver itself Although that obviously comes into play when comparing DIFFERENT drivers, it doesn't have too much bearing when comparing different-sized drivers of the same design. Theoretically speaking of course

 

[tRiGgEr 5,000+ posts]

Low end extension. That is all.

 

[RedStangHappy 10+ year member]

That's fine, even though we're back to the louder vs lower......But what, drivers being equal, will play the lowest...example 2 10" JL's or 4 8" JL's. If you know of a 8" sub going down to 15 or 20 Hz, even in a group, then let me know. Not that I think many 10's can but I think they'll get closer than an eight. I saw the numbers in decibels, but they were all at around 35 Hz. Not lower but louder, I'm looking to find out the answer to the original question. Enlighten me //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[audioholic 5,000+ posts]

There is no reason an array of 8's could not reproduce a 15-20hz note that would make you wet yourself.

 

[Hintzyboy 5,000+ posts]

That's fine, even though we're back to the louder vs lower......But what, drivers being equal, will play the lowest...example 2 10" JL's or 4 8" JL's. If you know of a 8" sub going down to 15 or 20 Hz, even in a group, then let me know. Not that I think many 10's can but I think they'll get closer than an eight. I saw the numbers in decibels, but they were all at around 35 Hz. Not lower but louder, I'm looking to find out the answer to the original question. Enlighten me //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

When speaking of low-end extension, lower and louder kind of go hand-in hand. You can't really isolate one from the other.

The lower the note, the more air you have to move to be able to hear it. This generally means that a single 10 will appear to play lower than a single 8. In reality, they are playing EXACTLY THE SAME NOTES. The only reason the 10 appears to play lower is because it is playing LOUDER at the given frequency. But if you add another 8" sub, the pair of 8s will have more surface area, meaning it will move more air, meaning it will play louder at a given frequency, meaning it will appear to play lower.

So, if a 10 and an 8 are perfectly equal except for size, the 4 8s will have better low-end extension than the 2 10s. Not because the 4 8s can play lower notes, but because they can play those same notes with more authority.

 

[cam5860 10+ year member]

After all this shit I'm finally starting to learn something! It took me 500 posts to understand why 10's will always be a better option than 8's. Because they have the abilty to play louder at a given frequency.

 

[Hintzyboy 5,000+ posts]

After all this shit I'm finally starting to learn something! It took me 500 posts to understand why 10's will always be a better option than 8's. Because they have the abilty to play louder at a given frequency.

God D A M N you are stupid!!! Seriously dude, life isn't working out for you. Try something else.

 

[cam5860 10+ year member]

Louder is always better! D a m n I love my 10's.

 

[helotaxi 5,000+ posts]

Louder is always better! D a m n I love my 10's.

Copy. Even though based on your own logic, 10s are clearly inferior to 12 which pale in comparison to 15s which don't compare to 18s. Your 10 are weak. You said it yourself in not so many words.