First off, sorry if this makes no sense, there is alot in that post i need to ask questions about haha
Ive broken it into paragraphs, hopefully that helps
The Yellow plot is the ISD preferred enclosure. QTC of .71 and 72 litres or almost exactly 2.5 cubic feet. The exact first box you drew (and sealed too!) SPOOKY ....
The Orange plot is also sealed but volume halved to 35 litres and the response differences would be inaudible both have a -3db point of 34 HZ
So basically, if i go with the sealed box it would make little to no difference if i built it at 35L or 72L?
Both sealed boxes will be nicely damped, soak up plenty of power and with the juice you are feeding them get crazy loud (before you add a second sub!) (1 driver in free air at 1000w in these boxes should be good for 120db hypothetically - before you add loading and cabin gain etc - i.e. louder than you should ever listen when driving and enough to damage hearing pretty quickly!). They both model very close to the 'ideal' .707 giving the best combination of power handling, extension and transient response (i.e quite deep, plenty fast, tight punchy bass - ideal for rock thru techno but higher Q's will give boomier bass that some ppl prefer for RnB and HipHop....)
Not to mention they are sooooo easy to build
This sounds like it would suit me great. 2 of these, based on what youve come up with there will be insane!
All the above (yellow and orange) is with sealed enclosures yeah? (which was, as you mentioned, my first preference anyway)
The Blue plot looks amazing - pretty flat down to 20Hz or so and noticeably (if not massively) more output from 20-50HZ than the sealed configurations... problem is the necessary 5.5" vent needs to be nearly 1.4 metres long (yes metres!). My brain is fried and I can't think of a way around this at 2AM! But maybe some more experienced builders than I can have a shot tomorrow? FWIW the Box is 62l (2.2 Cu Ft) and is tuned to 22Hz. this was the vented enclosure WinIsd put forward but i reckon is unrealistic due to vent issues. (To go shorter you need much smaller diameter and then you will have chuff city )
1.4m ?!?! thats just a bit too long haha
The pink plot is also a 2.2 cu Ft box, tuned to 32 Hz (35 looked quite similar). The good news is the same diameter port only needs to be 5" (125mm) diameter and 470mm long so would fit your original drawing. You also have Crazy output at the tuning frequency (an 8db gain) so repetitive thumps in the 30-45Hz region will be impressive - but it's peaky as hell and a long long way from being a 'musical' response. If you just want doof doof that may suit you but it could be very very tiring...Also, if going this way you will definitely need a subsonic filter below the tuning frequency or you will kill the subs in no time!
I definitely dont want it too peaky, which was one of my concerns at the start (which i didnt mention i dont think but should have)
Id be after a more musical response than peaky for sure
The one thing i would still check with these drivers though is if you do plan to port them, that they can still handle the power you want to put thru them... If not you will lose most of the SPL gain achieved from that configuration and have far less SQ than sealed as well.
well i think based on all that, a sealed enclosure will suit me better (as i originally said lol)
But just for reference, how would i go about checking what they could handle ported vs sealed?
Just modelled a 1.6 cu ft (45 litre) vented box tuned to 35hz and its plot is very similar to the pink 32 hz tune in a 2.2 cu ft box - only a sharper curve again! Same gain at tuning frequency but a slightly sharper climb getting there!
So this would be even more peaky over the original pink tune?