ok, some of you may be aware, my car = broken, bugered gearbox, clutch ground to dust...in a m8s garage till tuesday £100 to sort it, to ffing cold 4 me atm. soooo i thought id have a play, managed to get another set of qb69's for free off a m8, just had to buy new x-overs and grills. also had the 12" fli knocking around.....so 2 pairs of QB69's and 1 FLI 12" sub later....





cant wait to hook it up....

there is also a 12" VIBE black air mk2 plus, in a hand built and designed bandpass enclosure in red and black....this sounds like :O will post pics when i can be bothered to go downstairs to take em

any comments welcome good or bad

Slight off topic, the 2 holes you have in your shelf, where did you get them from and are ther smaller sizes available? (I want less than 1cm!).

Have you put any form of reinforcement under the MDF or are you using pretty thick MDF? My only concern there would be amps speaker wise

maplins!! or ebay, one is from maplins the other is from ebay, borrowed them from 2 different projects. and yes you can get them smaller....but not sure about 1cm
its 18mm mdf, not goin anywhere....i hope, i may think about some metal box section screwed into it, if it starts to look feeble...
well, i got the speakers wired up so they are 2 ohms rather than4, and my amp can produce more power across a 2ohm load than a 4 ohm, so in theory it SHOULD be ok...750watts rms across 2 ohms across 2 channels. and my sub's will haev similar setup, my sub amp can produce power till the cows come home...1500w rms across 2ohms bridged.

None of this makes sense why are you running a 12" sub free air. So you are going to be putting 750w RMS per pair of vibe 6x9's What are you putting through 12" fli sub because i wouldnt put more than 200w RMS through it even if it was in a box.

It looks like a tidy job but rubbish all the same and you figures seem to make no sense could you do a list of what amps you are using.

its being run free air, purley because of aesthetic purposes, also am i not right in saying that if i block the ports (which i know are doin sweet fa) that the sub and speakers will have an infinate baffel, which is the ideal condition for a speakers?nonono, 750w across 2 channels! ie 375 per channel, ie 375watts rms per pair of qb69's. nd yes i was also worried about the fli a little bit, its mainly in there as an experiment. i know its not gna take anywhere near what i can give it. the amp powering the 6x9's is one from "theloudest.com" dont laugh, i know its not great, but!! i bought it when that was all i could afford, and well now ive got money i havnt upgraded it because it seems to be just fine...and i have a BOSS amplifier for the two subs..cant remember which one, its bolted to the back of my seat...cx something or other...

good luck

OzMoSiS said:

good luck

Click to expand...

am i taking this as a complement or sarcasm.....

anyhoo, here are pics of the sub, bandpass, in red and black







that is by no means an "experiment" its properly calculated, and fabricated, and as a result sounds :O

keep the vibe, flog the rest and by a decent set of components, amp it all up and bingo something sounding pretty reasonable.:slayer:

6x9s really do not add anything to any system, most of the time a sub will distort any sound coming from them, and to run the fli free air, will cause it to over extend and burnout pretty damn fast.

hmmmm, i think your right, as already started, this is realy a bit of play, ill hook it up to see what happens, purley out of interest, and when i get my stilo, i will do it seriously with some nice DLS components, see how the vibe in its box stacks up....and go from there, but thisll do till then i think....always wanted to fry a sub..

What did you use to calculate the size of the bandpass because??? The sub simply wont work free air, by all means give it a go the more fried Fli subs the better LOL. But they were not designed for this purpose (or any other purpose to that matter) and will not really make any sound at all to run Infinite baffle you have to have an Infinite baffle sub.
I dont think that theloudest.com multi channel amps are stable at 2ohms so that could flaw you plan.
Dont get me wrong if you dont mind blowing the equipment then carry on the best way to learn how to not do things is experimentation im sure we have all done it.

i like the smell of smoke, even in its box the fli sounded wet and silly, ahh theloudest.com 1 says it can support 2ohms....again if it dies no biggie, just means i have to get a new nice one
more serious stuff:
i used a program called bass box pro to give me a starting point for the bandpass, then i used maths and time to come up with a deisgn of box that would give me the exact volume i needed in both chambers that was exactly as long and as tall as will fit in a mk1 punto boot..with a few lil web apps helping me, telling me what each section was tuned to, the front is 50hz, and the rear (with the port) is 40hz, bassboxpro also has a port tuning facility that enabled my odd shaped port to be tuned to the correct freq. it's my second box the 1st one i made was for an eminance 327 8" sub...i calculated wrong it came out 1.5m long and 1m wide, only when i started reading did i realise id done it wrong lol. but the bandpass is gooooood

Hmm did you choose the 40hz tuning yourself or is that what the program came up with personally if you already have a 50hz tune (sorry i dont understand Bandpass very well so dont know how the front gets tuned i presume it is done by the length of the front) then i would have dropped to say 27-30 for the port so you can drop low but tight with more definition between the 2 tunings.

was kind of forced to have it at that freq due to mounding depth of the sub,
bandpass is two enclosures on one sub, front has one rear has another, one is ported the other isnt. imagine it like two boxes bolted together with a sub in the middle, they get the most sound possible from one sub. you can tune the front by changing the depth of the front enclosure (what you said i think). the front was designed to be tuned at 50hz, just have to live with the back...altho on box no3 (havnt decided which sub ima use) ill probably tune one to 50 and the other to alot lower ( like you said).

Ahh what budget for the new sub and what amp i may have a few suggestions.

LOL no idea yet m8, errrrrrm, probably £100 for sub and maybe £150 for amp, so probably talkin £200-£300 all in, ideally a lil less...altho the amp i got now seems good...may demote this 1 to other speakers and get another one for new sub...

Well let me know when you want a sub i have a sub in mind but am awaiting a hearing the thing but 800w RMS in your £100 budget and it doesnt carry the silly vibe name

:O i like vibe, u made me cry....lol was thinking a vibe space? ive heard one, sounds good...also been looking at a JL audio 1....long time to decide yet tho....need 2 wait for car no2 sum time later this year, probably next half...always glad for some help tho...

:O:O:O i fitted the parcel shelf today, after asking the people at boss what would happen if i bridged my amp at 2 ohms there reply was "It will blow up if you bridge it with a 2 ohm load. Thank you for choosing Boss Audio product. " so i didnt lolol, i connected it bridged thru 8ohms (after calculating matched impedance of the amp to be ~9) so max power transfer bridged at 8. and OMG i know people slated the equipment, and it was a bit of fun, but its totally different, much much much more punchy, more refined trebble, and a lil bit more bass (good lil fly lol) not bad for a freebie!!

So are all the speaker on the parcel shelf wired together.

ones on the left are on a single channel, ones on the right are on single channel, (L & R) subs are on same channel, 2 ohms per channel, bridged in series to make 8ohms