Ive seen this mention concerning 4th orders a few times, but can anyone explain the pros and cons of the various Ratios concerning 4th and only 4th order bandpass boxes?
From what ive read, in general keep the sealed section small, and make the ported section as large as possible, but ive seen a few small builds that worked quite well with the 1:1 ratio. I always tried to stick with the 2:1 and the 3:1 was usually out of the question because of space limits.
A 1:1 ratio would open up more possibilities for me as far as down the road for a bigger build.
Generally, the larger the front chamber is in relation to the rear chamber, the more efficient the enclosure is.
In many of the 4th orders I've graphed, according to those graphs with a 1:1 sealed to ported the output wasnt quite as good, but the frequency response was smoother/flatter
Then again...this is just according to my little program...
1:1 tends to show up alot for flat response as said before
anything besides flat is a guessing game... u could get a chit ton of gain at 2-3notes but it could fall off very fast on both sides... so it all depends on what the goal is too, burping or daily
worst of all is that most off the time u dont hear the subwoofer start struggling since its inside and noises can be filtered out by the port... so playing far outside of the bandwidth designed can cause some damage
1:1 tends to show up alot for flat response as said before
anything besides flat is a guessing game... u could get a chit ton of gain at 2-3notes but it could fall off very fast on both sides... so it all depends on what the goal is too, burping or daily
worst of all is that most off the time u dont hear the subwoofer start struggling since its inside and noises can be filtered out by the port... so playing far outside of the bandwidth designed can cause some damage
Makes sense, and thanks for the responses fellas. I believe when I build my test box ill try a 1:1 as a flat response or as close to it as i can get is what im seeking.
Interested to get some more input on this. Really though, how many people handing out info on 4th orders actually know from experience? And I'm not talking about what you heard in someone's car. I mean how many of you have actually built several 4th orders to test what works better?
im going by bbp and winisd, ive honestly never ran across a fourth order requiring a 6:1 ratio
hell sometimes the ported chamber is a bit smaller, it all depends on the parameters of the sub, u cannot create some magical ratio that applies to any speaker ever made
thats retarded if people think that
example on winisd:
sa12 - .6sealed, 1.1ported, 43hz
hdc318 - 1.6, 2.8, 48hz
tc3k - 1, 1.2, 45hz
granted these are theoretical, but u can see there is no golden rule that applies to all three
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