Jump to content
Sign in to follow this  
midnightE39

box rebuild for an SSD15.

Recommended Posts

So ive currently have got an Fi SSD15 in a 3 cube box, ported tuned around 31 hz. it murders the lows, and theres no port noise that i can tell despite it having only about 11 sq inches per cubic foot of box volume.

 

the problem is, there seems to be cancellation in the 50-65hz range. it hits great below that and even gets louder over 65hz until it starts rolling off around 85hz.

 

this is in the trunk of a 2001 BMW 525i. i have the sub fired up with the port back. im very frustrated with this lack of a crucial sub bass octave. i'm about to build a new box, in the neighborhood of 4 cubes with a port tuned around 35 hz, with at least 14 sq inches per cubic foot of internal volume. should this fix my problem? i'd really appreciate some guidance here. it isnt my car's fault, because i used to have 2 kicker CVR 12s tuned @ 40hz that hit this range of bass just great. when it comes to box size, is bigger always better as long as the port ratio remains proper? could it be because my sub is fired straight up? with only aobut 4-5 inches between it and the trunk roof? help me understand what to do to get my 55-65hz range back please. i waited a month for my Fi subwoofer and ive been very pleased with it otherwise except for this one thing.

 

thanks in advance.

Share this post


Link to post
Share on other sites

There is no relation between box volume and port area.  At all.

 

There could be a few reasons for your lack of 55-65Hz range.  But first off, have you swept with test tones to be sure you actually have a dip in output in that range or are you taking a guess?

 

One of the most common reasons for this response is an exxagerated low end.  This normally happens when an alignment thta is relatively flat (like yours) anechoically is placed in a car with a ton of cabin gain down low.  It is like you have just added 10db+ on your last few octaves, and then you don't get so much boost right above that.  It pretty much makes it sound like you have a big hole in your response, and in reality you do.  The easiest solution for this is picking an alignment that isn't flat, but instead is rolled off more on th elow end with a higher ripple in response up higher, no doubt that is how your setput with the Kickers was working.  This is why many people find they like the sound off a seale dbox because it is "punchy" hits th ehigher notes better.  But in reality, they just have an alignment that peaks in mor eof the range they want, it has little to do with the box actually being sealed.  By the way, you can make a ported box peak wherever you want by manipulating tuning and box volume (notice port area isn't mentioned, because it doesn't play into anything here) but you always have to give something to get something.  So if you make a box that has a peak up high, you will loose low end and possibly have some other undesirable after effects...

 

The other common problem (well not so common) is actuall cancellation due to the sound waves arriving at the listener at slightly different times and cancelling each other out.  The only way to fix this is to move the enclosure, or change orientation.  Sometimes this problem is very tough to overcome with drastic system changes.  This i sone of the biggest reasons some cars are so much louder than others (inside) with identical equipment...

 

Hope this helps...

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

    1. Recent Topics

        • 76 comments
        • 2,207 views
        • 8 comments
        • 314 views
        • 11 comments
        • 121 views
        • 17 comments
        • 164 views
        • 1 comment
        • 30 views
        • 1 comment
        • 41 views
  • Similar Content

    • By DedicatedEnthusiast
      I am selling a pair of B2 Audio X2C 15's that were assembled by Jay Holm in Denmark and custom modded for me and my extreme daily driving abuse.
       
      I am willing to let them go for $1,000 each shipped or $1,800 for the pair. 
       
      Reason I am selling them is because they have managed to crack not one but two gas tanks now on my car, I can provide shop receipts for anyone who would like to see proof.
       
      Also they have broken the spoiler wing off my trunk a long time ago so are basically destroying my car and I cannot afford to keep fixing it.
       
      The link below shows a video of the subs and system playing from B2 Audio's YouTube page. I do not own the video that they edited here but I did submit the original footage to them from my cell phone for the fans and public to see.
       

       
      The box was built by Cherryman Customs in Tennessee and is double layered (1.5" thick) all the way around. It is 10 cu ft net inside with a tuning of 27hz and has a lexan glass bullet proof window that provides view of the subs inside with red L.E.D. lights that illuminate. 
       
      Measurements are 36" W x 20.5" H x 46" D
       
      If interested I am willing to let it go for $500 picked up or you pay shipping.
       
      Any additional questions or concerns please feel free to PM and ask me. 
       

       

       

       

       

       

       
       
       
    • By DedicatedEnthusiast
      Hi guys I was wondering whether standard polyurethane or a UV activated resin would be better for applying directly to MDF wood in order to protect it from the elements of rain ice and snow basically is one product more durable or reliable than another with respect to weather-proofing wood thanks
    • By boxbuildshoutout
      Hello everyone I would like to start by saying I have no intention of breaking or bending any site or community rules here so pls forgive me if I do that is not my intention. 
       
      I am here to share my personal experience with cherrymancustoms who has built me an extremely personalized and truly custom enclosure to meet the needs of my particular listening goals.
       
      This man has spent literally countless hours over-the-phone speaking with me one on one in an attempt to maximize my enclosure design and has built what I consider to be a very good quality box. I have attached images for your own viewing and judgement below.
       
      His website is www.cherrymancustoms.com/ where he has a phone number listed for you to contact him if you so choose to do. He also has a YouTube account and forum thread over at caraudio.com
       
      I plan on again encouraging him to create an account here so he can communicate with you guys easily and share all of his work here locally with the community.
       
      FYI this box was built with an adjustable internal volume and adjustable tuning plus it is "double walled" everywhere from top to bottom and side to side. It features some serious bracing too.
       
      For any of you looking for someone to build and create exactly what you have in mind or rather those of you who need somebody to help you determine what would be best for your needs I strongly encourage you to give this man a chance he is super friendly, knowledgeable and hard-working as you can see.
       
      Best of wishes to everyone here hope some of you may find this information to be of good use.
       

       

       

       

       
    • By mikebingham34
      Hey everyone, 
      First off I wanna apologize for changing my mind so much. My financial situation has changed, so my future setup ideas have too. Even though I have not followed through with other plans ya'll have helped me with, I have learned a lot for each comment or post I read.
       
      On to the enclosure idea. I will be getting a single SA-10 D2 as soon as my current setup sells. I will be running it off of a BRZ1200 @ 1 Ohm (for headroom). My goals are for it to be decently loud (I have had an E-12, hope to be comparable to that), and flat sounding for all music types... From dubstep to decaf to classic rock to country. It will be in my daily which is the trunk of a 2000 Honda Civic Sedan (DX EJ6, D16Y7 Auto). I am planning on building an enclosure that is 1.4 cubic feet, with a 17" long, 4" aeroport, tuned to 34.8 Hz. 
       
      My questions are as follows:
      Is the box too large? I commonly see Jacob recommending 1-1.25 cubes for a ported SA-10.
      Should I keep the 4" aero? It gives 9" of port per cube (high end of the spectrum for an aero)
      Or go with a 3", or just go slot port... If I go slot, what kind of port area should I use?
      Lastly, is that a good tuning? I would like an F3 around 28Hz. 
       
      Thank you for all your help, as always. 
  • Recent YouTube Posts

×