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Kangaroux
01-07-2012, 03:36 PM
Well I'm bored today so I was fooling around with my current box design and turns out I'm tuned to 26 instead of 27, which is lame because I wanted to be closer to 28 then 26. My port is really long right now (nearly 44") and if I cut off around 6" of port my tuning doesn't really move but I gain quite a bit of air space back (around .5 cubes, which brings me up to 6 cubes net as opposed to my current 5.5). I then cut off another 6" and my tuning went up to 30hz with my box volume around 6.4 cubes net.

I love how it sounds right now but 26hz is really unnecessary for a tuning for me. I want my setup to be louder and since I don't listen to anything below 27 it isn't worth it to tune that low anyways. I've hit a barrier with my amp where if I turn up the gain anymore my voltage starts bombing hard and my sub starts receiving a clipped signal. The big issue I have is because the box is small the sub needs more power to reach it's full potential, and my electrical is restricting my amp. Will gaining an extra cube help a lot with my efficiency? And will I notice greater output by going from ~26hz to 30hz? By tuning so low I've really restricted myself to the kind of music I can listen to. If I listen to any drum and bass or dubstep that has a note over 50hz it sounds meh.

Before anyone asks, I can't really tune above 30hz. The Fi Q is made to operate under a 30hz tuning, and although this sub is a custom, I don't have any specs to work from and I'd rather not tune any higher. Cutting down my port involves quite literally cutting down the port inside the box with a jig saw. Once I cut it down I can't bring my tuning back down, so I want to make sure if I go through with this I will be happy with the results.

CLIFFS: Will bringing my box from 5.5 @ 26 up to 6.4 @ 30 greatly increase efficiency and output?

CAT MAN
01-07-2012, 03:48 PM
um why are you tuned so low in the first place? i would go up to 33-35 . and yes output would be alot better

Kangaroux
01-07-2012, 03:52 PM
Main goal was for lows which is what this puts out but I'm looking for more output. And read the last paragraph

CAT MAN
01-07-2012, 03:53 PM
Main goal was for lows which is what this puts out but I'm looking for more output. And read the last paragraph

you can go above 30hz tuning. its just reccomended not too. dont worry about it and go mid-lower 30s

Kangaroux
01-07-2012, 03:57 PM
you can go above 30hz tuning. its just reccomended not too. dont worry about it and go mid-lower 30s

And that's what I'm worried about. Once I raise my tuning I can't go back. I don't want to raise it too much and then be disappointed and have to build another box, because frankly I don't have the money to be building another box. My last setup was tuned at 30 and I loved it, I don't listen to stuff that's high enough to really need a higher tuning

CAT MAN
01-07-2012, 03:58 PM
And that's what I'm worried about. Once I raise my tuning I can't go back. I don't want to raise it too much and then be disappointed and have to build another box, because frankly I don't have the money to be building another box. My last setup was tuned at 30 and I loved it, I don't listen to stuff that's high enough to really need a higher tuning

33 seems to be the median between output and lows IMO... im tuned to 40 but my car drops tuning a good bit and i can dig into the low 30s

ahole-ic
01-07-2012, 04:22 PM
There is so much you are ignoring or just don't know. Tuning as low as you are is what is killing your output. Usually your port is near another surface in your vehicle and that actually acts like external port length and drops your tuning like crazy. So you could be tuned SUPER low. You're not going to be missing out on any lows tuned at 35hz. Most people unknowingly tune at 38-42hz, the vehicle drops their tuning to ~32hz (anyone with port back has this happen) and they are low end monsters. Your sub will be just fine raised up.

With all of that said, don't cut your current port with a jigsaw. Build a new one. If you don't cut it absolutely perfectly (you won't... it's a jigsaw) then your tuning will be all jacked up. Don't be ghetto. Build a new box and tune it to at least 35hz or higher. You will be glad you did.

CAT MAN
01-07-2012, 04:23 PM
there is so much you are ignoring or just don't know. Tuning as low as you are is what is killing your output. Usually your port is near another surface in your vehicle and that actually acts like external port length and drops your tuning like crazy. So you could be tuned super low. You're not going to be missing out on any lows tuned at 35hz. Most people unknowingly tune at 38-42hz, the vehicle drops their tuning to ~32hz (anyone with port back has this happen) and they are low end monsters. Your sub will be just fine raised up.

With all of that said, don't cut your current port with a jigsaw. Build a new one. If you don't cut it absolutely perfectly (you won't... It's a jigsaw) then your tuning will be all jacked up. Don't be ghetto. Build a new box and tune it to at least 35hz or higher. You will be glad you did.

bam

Kangaroux
01-07-2012, 04:30 PM
There is so much you are ignoring or just don't know. Tuning as low as you are is what is killing your output. Usually your port is near another surface in your vehicle and that actually acts like external port length and drops your tuning like crazy. So you could be tuned SUPER low. You're not going to be missing out on any lows tuned at 35hz. Most people unknowingly tune at 38-42hz, the vehicle drops their tuning to ~32hz (anyone with port back has this happen) and they are low end monsters. Your sub will be just fine raised up.

With all of that said, don't cut your current port with a jigsaw. Build a new one. If you don't cut it absolutely perfectly (you won't... it's a jigsaw) then your tuning will be all jacked up. Don't be ghetto. Build a new box and tune it to at least 35hz or higher. You will be glad you did.

I have 2 port pieces that are each around 18" long. If I knock out one of the port pieces all together then my tuning goes up to 32. I'll then just use some liquid nails and seal up everything good from the unused screw holes. It may not be the perfect way of doing things but tbh I don't have money to be going out and buying more sheets of wood. This box used 1 1/2 sheets of wood, and I used the leftover to build some extra stuff so I don't have any more leftovers besides small scraps

05fronty
01-07-2012, 04:31 PM
my last box was 38 hz. seems like it didn't hit the lows right. so now i am trying to decide either 33 or 35hz myself jesse.

Kangaroux
01-07-2012, 04:33 PM
my last box was 38 hz. seems like it didn't hit the lows right. so now i am trying to decide either 33 or 35hz myself jesse.

Was your port loading off into anything? Cause mine loads off into the hatch and it sounds awesome, just dont need it tuned so low lol

05fronty
01-07-2012, 04:37 PM
Was your port loading off into anything? Cause mine loads off into the hatch and it sounds awesome, just dont need it tuned so low lol

roof. you remember my last box. subs up and port up. put up decent numbers also

wenn_du_weinst
01-07-2012, 04:43 PM
my box is tuned to 56hz and plays down to single digits, you need more info to know how it will respond just by knocking out part of the port.

Kangaroux
01-07-2012, 06:04 PM
Well I went ahead and took out one of the pieces...tuning def. went up a few but I'd say it's sitting around 30-31 because of it loading off into the hatch. High end response went up which is nice, and it's overall louder. No problem playing down to 24hz and it doesn't really unload any like I worried it would. Overall this is a success lol. For my next box I'm definitely using aero ports so I can play around with tuning, much easier than trying to knock out a port and then getting it through the sub cutout (that was fun)

double 07
01-07-2012, 07:30 PM
Good job.....glad it worked out!!!

wenn_du_weinst
01-07-2012, 08:13 PM
another trick to playing low while not losing the highs is facing your subs back, I don't know if you can do that with 18's in your car though.

kramer_212
01-07-2012, 08:27 PM
There is so much you are ignoring or just don't know. Tuning as low as you are is what is killing your output. Usually your port is near another surface in your vehicle and that actually acts like external port length and drops your tuning like crazy. So you could be tuned SUPER low. You're not going to be missing out on any lows tuned at 35hz. Most people unknowingly tune at 38-42hz, the vehicle drops their tuning to ~32hz (anyone with port back has this happen) and they are low end monsters. Your sub will be just fine raised up.

With all of that said, don't cut your current port with a jigsaw. Build a new one. If you don't cut it absolutely perfectly (you won't... it's a jigsaw) then your tuning will be all jacked up. Don't be ghetto. Build a new box and tune it to at least 35hz or higher. You will be glad you did.

e crack has spoken.

Kangaroux
01-07-2012, 09:08 PM
another trick to playing low while not losing the highs is facing your subs back, I don't know if you can do that with 18's in your car though.

You mean doing like sub back port back? I could do that but it sounds fine right now imo.