Slot-Ported Mini Subwoofer




Introduction: Slot-Ported Mini Subwoofer

About: Interested in audio (speakers, subwoofers etc.), high voltage power supplies and lasers! :D Follow me for more instructables!

In this instructable (my first) I will show you how to make a mini portable Slot-ported Subwoofer!
Please leave comments - be critical but nice as this is my first instructable and I am only fifteen.


Step 1: Ingredients - What You'll Need

First of all and obviously:
>A Speaker
>Some Cardboard
>Craft Knife

>A small amplifier, i have a tiny amp (shown) which suprisingly is capable of supplying enough power for the Peerless 3.5" 60w woofer I used.
>Wire, any will do, I used standard black and red audio cable.
>Some decent tunes to knock through the finished speaker!

Step 2: The Pieces

You'll need to mark out the pieces of cardboard to fit your speaker and you preference.
Here i went for:
(1) 20x30cm
(1) 20x27cm
(2) 20x15cm
(2) 15x30cm
(1) 12x20cm (for Bass Port)

Step 3: Cut! Cut! Cut!

Now for the tricky bit. Cut out all the pieces. I have injured myself very badly from various craft knives and therefore asked an understanding adult, in this case my dad, to help.

Step 4: Try It Out

Now you need to lay out the pieces in the way you are going to stitch them together. or glue. or tape. LOL

Step 5: More Cutting

cut out the hole for the driver in this case
Diameter of cutout = 92mm

Step 6: Tape It Up

now you need to fix all the joints between the pieces and affix the driver. i went for bolts!

Step 7: Now to Seal It

Tape it up so that it is sealed and ready for use. Don't forget to wire it (thats what I did) duh :)

Step 8: Nearly There

Almost done now. I fed the audio cable through the port thus illiminating the need for another hole to be made.

Step 9: Plug in and Rock

Find an amplifier and a source of music. its plug in and play!

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    5 years ago

    can you tell me how to make a low pass filter for this project so that it sounds even bettr im thinking the cut off frequency as a 100hz


    11 years ago on Introduction

     funny little peerless but i would think it would be more for midrange than bass.
    also id use thicker card and extend the port sideways so its and L instead of a l thats how a real L-port goes. next step is a 12" in a MDF box? your mum would love that! lol. nice little project for when your bored though. but you should try a 12" or atleast and 8" in a wood box next! once you go big, you never go back!

    Da Nugesta
    Da Nugesta

    Reply 11 years ago on Introduction

    guess what! im waiting for an 8 inch sub which has 16mm xmax and is 120w RMS. it has a 4 layer VC which is 2 inch diameter an 1 inch winding. i am buying a 200w RMS sub plate amplifier and building the box outta MDF.

    u say the peerless is a mid but it has 7mm Xmax and it chucks out more bass than my more pricy 5.25 and the peerless is a 3.5! :)

    you also said dont go back, go bigger. later im going to make a ported 18" ! :-)


    Reply 11 years ago on Introduction

     woah! from a 3.5"? better than a 5.25? Damn it must be good.

    cool i was going to get a 18" 1800watt car subwoofer. what one were you thinking of? id tune it to low 20s if you have space that way you will pick up the real low bass in movies and songs and whatever else you play on it. i for 18Hz tuning you need a 6-8 CUBIC FOOT box!!! 

    you should do an instructable of both of them. we need some decent speaker 'ibles on here and im too lazy :-P!

    Da Nugesta
    Da Nugesta

    Reply 11 years ago on Introduction

    im not making a instructable of the 8 inch sub, cos people would tease me for the driver im using. im no longer getting that nice 8 inch, im getting a 8 inch type e (alpine). the 18 inch is a budget paper cone paper surround woof from DJ sound kit. it is like £36 which is great for a 18.
    and yer, also i no longer hav the peerless. a giant glass dice i have fell on it and bent the coil :( damn gravity :-P.

    you said about google RE vented designer. i cant find it :( can u show me a link :)


    Reply 11 years ago on Introduction

    they have 8" alpine subs? never new that. i thought they only had 10"+.
    damn thats cheap for a 18"! how many watts and whats the xmax? 
    the one im getting is 300NZD so about 3 times more than yours its a blaupunkt velocity car sub at less than 1/3rd the normal price :-). i'll have to wait a while though because im getting a PSP atm (not the stupid GO ones, a normal one)
    awww poor peerless :-(. yeah gravity sucks sometimes.

    here it is:


    Reply 11 years ago on Introduction

     oh and google RE enclosure calculator. a handy tool for tuneing L-ports! :-)


    12 years ago on Introduction

    "Trusty Sellotape (no branding there! LOL)" har tho that is a brandname XD nice box :) sealed nicely so u get no buzz? also wouldnt u have a wall or something for compression on the port? summin 2/3 the depth mebe..

    Da Nugesta
    Da Nugesta

    Reply 12 years ago on Introduction

    there is a wall if you look on step 7 as the wire goes up it goes behind the compression wall