Rsd 12d

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lukeman269
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Rsd 12d

Post by lukeman269 »

How long does it typically take this sub to loosen up? I'm not too impressed with the output of the sub as of right now. I have played the sub for about 2 hours so far.
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Bfowler
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Post by Bfowler »

about 10 hours.

it wont get much louder during the break in though. just sound more natural.

how loud were you hoping for? you should be sitting around 136db with alpine amp mentioned in the other thread.

the sub is by no means a spl sub, but couple thing to consider...


a: most modern 12's move about the same amount of air.

b: it takes about twice the power to create a note 1 octave lower. for example, it takes twice as much power to make a 30hz tone as a 60hz tone.

so what you can gather from that^ is that if you are going with a single 12, you have to make trade off's for how low you want to play vs how loud you want to play.

the rsd is made to play very low, at a trade off of overall volume.


thats also why subs by brands like kicker and mtx sound so loud. trade low note production, for overall volume. sort of like how some engines are tuned for high torque vs high horsepower

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stipud
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Post by stipud »

Bfowler wrote:b: it takes about twice the power to create a note 1 octave lower. for example, it takes twice as much power to make a 30hz tone as a 60hz tone.
Can you explain this a bit? Without boost it should be the same amount of power regardless of frequency.
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Bfowler
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Post by Bfowler »

yeah, that is not well explained.

for the same sub, in the same conditions, it needs twice the power to play tone at 30hz then it does at 60 at the same volume.

that is by no means a exact sciance just a rule of thumb a pg tech explained to me (pretty sure it was brett in the day)
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stipud
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Post by stipud »

Bfowler wrote:yeah, that is not well explained.

for the same sub, in the same conditions, it needs twice the power to play tone at 30hz then it does at 60 at the same volume.

that is by no means a exact sciance just a rule of thumb a pg tech explained to me (pretty sure it was brett in the day)
Well the amp basically puts out the same power regardless of frequency, so I assume you/he are talking about the sub's frequency roll off. However that is generally reversed by the cabin gain. So assuming the cabin gain slope matches and opposes the speaker rolloff rate, the end result should be almost no power differences between 30 and 60Hz at the same volume.

One of the main factors in designing a sub is choosing where exactly to let it roll off naturally. The RSDC is biased towards a lower frequency rolloff moreso than many traditional "street boomer" subs, which are biased towards 60Hz+. With the in-car gain in most cars the RSDCs are usually a bit bottom heavy, while boomer subs will have a peak around 60Hz and then roll off in the lower end. While the boomer subs will sound "louder" (since the ear is more sensitive to higher frequencies), the RSDC has a much more natural sound reproduction.

However, unlike the Xenon series the RSDC's arent OVERLY biased towards low end and are still quite competent at high end bass. I would be surprised if anyone would be disappointed with the output with reasonable powering.
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Bfowler
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Post by Bfowler »

he just has the normal rsd. i kind of want to set up a test now!
my ex-girlfriend said "its car audio or me"
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