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Precision Port 4" Flared Speaker Cabinet Port Tube Kit

Brand:|Model: PSP4-BKHT|Part # 268-352
The unique flared-end construction of the Precision Port system enables it to outperform any standard port tube on the market. Conventional tubes suffer from nasty turbulence at the entrance and exit of the port, producing unwanted noise and poor sound quality.
Due In: 5/11/2016
List Price$19.99
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Part # 268-352
  • Reduces air turbulence to minimize or eliminate port noise
  • Gives your enclosures a sleek, professional look
  • Just cut to length, glue together, and install
  • Mounts in 6-1/4" diameter cutout

Product Details

Precision Port 4" Flared Speaker Cabinet Port Tube Kit

The unique flared-end construction of the Precision Port™ system enables it to outperform any standard port tube on the market. Conventional tubes suffer from nasty turbulence at the entrance and exit of the port, producing unwanted noise and poor sound quality. The Precision Port™ system overcomes these problems and as a result can actually produce a gain of up to 3 dB in output!

Now you can experience good looks, low distortion, and superior overall sound quality thanks to the Precision Port™ system. Convenient front screw holes make this tube easier to install than others on the market. Create a port up to 17" long, then glue with ABS glue found at any hardware store. Installation instructions included. Dimensions: • 7-1/4" outside flare outer diameter • 6-1/4" cutout • 6-3/16" inside flare outer diameter. Also available in 2", 3", and 6" diameters. Proudly made in the USA!

To calculate the proper port length for your cabinet and tuning, use Precision Sound Products' Port Length Calculator.

Precision Port 4" Flared Speaker Cabinet Port Tube Kit
  • BrandPrecision Sound
  • ModelPSP4-BKHT
  • Part Number268-352
  • UPC844632046797
  • Product CategorySpeaker Port Tubes
  • Unit of MeasureEA
  • Product Rating
    (63 Reviews)
  • Weight1.64 lbs.
  • California Prop 65

    Warning: California residents only. Please note per Proposition 65 that this product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

View similar products to the Precision Port 4" Flared Speaker Cabinet Port Tube Kit
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Precision Port 4" Flared Speaker Cabinet Port Tube Kit
Precision Port 4" Flared Speaker Cabinet Port Tube Kit is rated 4.7302 out of 5 by 63.
Rated 5 out of 5 by from Easy to use/ durable portBought this port for a custom ported box that goes behind my back seat of my 2008 tacoma double cab. I made the base depth of the box to be 8 inches and the port flare diameter is about 7.25 so it was cutting it kind of close. I probably should have gone with a 3 inch port so I didn't have to modify this one. This port is working great so far. I used standard PVC glue to hold it together. Running a 10" Alpine Type R at 500 rms and I have to port tuned to about 39 Hz. I cut the port to an overall length of 16 inches. Definitely go with a flared port, it sounds awesome in my truck.
Date published: 2014-12-01
Rated 5 out of 5 by from port noise! what port noise?these ports does an excellent job of bringing out some smooth,clean,clear and loud bass.
Date published: 2014-10-12
Rated 5 out of 5 by from Doesn't play well with Dayton portsPrecision and Dayton ports of the same size do not interchange, such as I need two 26 inch long ports and have to use a 90 at about 14 inches. I also bought Dayton 4" 90's and the lengths assuming they'd work together. They don't. So with some glueing and piecing together, I've managed to make what I need, but the two ports are different, so don't make the same mistake I did. Other then that, it's great and Parts Express always get's me what I need fast.
Date published: 2014-10-11
Rated 5 out of 5 by from Awesome productI used two of the 4 inch ports an built a sub enclosure for a local stereo shop and they were amazed at the way it sounded
Date published: 2014-06-01
Rated 5 out of 5 by from Flared PortExactly what I needed! No 'huffing' at all and made a huge difference in sound quality! Highly recommend
Date published: 2014-02-23
Rated 5 out of 5 by from As advertised, good fitment, good documentationThis was exactly what I needed to finish my sub build. The parts fit together perfectly, and the necessary calculations are provided in case you don't have a box design program or something else.The only niggle I have is that it would be really great if they included a small packet of PVC adhesive, as this is not something most people keep around. It would save some folks a trip to the store for maybe $1 additional cost. It's a very minor gripe.Great product!
Date published: 2013-06-07
Rated 5 out of 5 by from Best port ever!!I purchased two of these ports for a custom box. I've always been told that flared ports sound better then jus straight pcv pipe. So i decided to test the difference. I installed straight pipe ports first and listened to it, sounded good. I then installed these flared ports and I was blown away by the difference in sound. It sounded sooo much cleaner, louder, and tighter. I highly recommend if you want a loud and good sounding box.
Date published: 2012-12-19
Rated 5 out of 5 by from Does what it was suppose to doIt tuned my tunes lol. Be careful screwing it in, if you go to far it will break!!
Date published: 2012-12-16
Rated 5 out of 5 by from excellent portThis port is undoubtably strong enough for any build, and long enough for nearly any application. It is also fairly cheap considering I bought 4 of these so I saved the $5 or so but I have the 4 of them 13 inches long firing up along with subs faceing up in an 8.5-9 cubed box, and they knock with no problems at all. Would definitely recommend.
Date published: 2012-12-04
Rated 5 out of 5 by from beats PVC pipe and looks and sounds a lot better tooused 3 of these in a dual 18" subwoofer cabinet with no huffing or port noisethe flares look great and are easy to flush mount for a professional look*tip; instead of using PVC pipe glue just use duct tape so you can change the port length if needed, also I always mount the rear of the port in an internal brace to keep the port from just "hanging" in the box
Date published: 2012-06-23
Rated 5 out of 5 by from Amazing!these ports greatly increased the volume of my sound system. a must buy if you are making or have custom sub boxes
Date published: 2012-05-09
Rated 5 out of 5 by from Precision Port brings an end to chuffingthe 4" precision port is awesome! I installed it in a 1.4ft^ft3 box tuned to 32hz (port length unchanged) with 2 8" subs (at around 200W). The air movement was at around 19m/s (which might creating port noise) but this port does not chuff at all and sounds decent! Tried playing around by putting a sheet of paper near the port, it rips it with ease. :)Instead of using PVC glue, I used the ABS glue, which bonds them together permanently. ABS literally melts the plastic on contact, so don't apply too much.It's a solid port, and I would highly recommend it.
Date published: 2011-06-30
Rated 4 out of 5 by from easy fast goodI put one of these in a pro bass cab. it had a small port and was chuffing at high volumes. I was also dissatisfied by the LF power and color.This port tube did the trick. the cab is warmer, smoother, and has MUCH better LF response- the low B is kickin.Install was easy and I found cutting the tube to their recommended lenth (calculation sheet included) was the best of all the different lengths that I tried. I needed to use speaker gasketing tape (also available here at PE) to seal the vent. My only recommendation is this- instead of 4 screws to mount, 6 screws would be more secure. That is easily done with a drill and screws. . .
Date published: 2011-04-22
Rated 4 out of 5 by from Very nice, FragileWorked great, little PVC glue and away you go! Be careful not to over-tighten the screws used to hold it in, it doesn't give much and will crack...personal experience.
Date published: 2011-03-14
Rated 5 out of 5 by from Great Sound,Even Better Price!!Same as a PNR Port or Aero Port. These give you much cleaner bass than regular ports and raises your decibals. I used one port for One High Excursion 600W RMS 10" and it sounds great now i just need a bigger amp ;-)
Date published: 2009-12-17
Rated 5 out of 5 by from These are terrific, I bought 8 of them!Great Product !They have a website at that will calculate the total length of the ducted tuned port. The first number is without the flares attached & the second number is with the flares attached. The difference between the 2 numbers is the length of pipe you need to fit between the flares!
Date published: 2009-12-02
Rated 5 out of 5 by from These ports are hugeThese ports do the job. I had 2 12" Polk momos in a sealed box in my car. I decided to buy a pair of these and port a larger sealed box I already had. Installation was simle, if you have a drill and a jigsaw. The hole needs to be very large, it is actually the same size as the inner flare, as you use that as a template. Instructions include the math on how to obtain the correct length of the tube, but you need to know the volume of your box and the desired frequency you want the tube to be tuned to. I don't hear any port noise at the max volume I listen to.
Date published: 2009-11-05
Rated 5 out of 5 by from best portI have had many subwoofer boxes mostly slot ported boxes this port is great i have three in my box for a 15" monster subwoofer and the quality is great i will always buy these ports for my boxes in the future. the first to i bought i paid 60 for the pair, i needed one more so i started looling on the net and found this web sight and found them for 13 so this is a great deal.
Date published: 2009-11-02
Rated 5 out of 5 by from Great alternative to slot portingI purchased this to replace a standard cardboard port in an enclosure I built for a Diamond Audion D6 15" sub. I am very happy with the cosmetics of the tube. The face does have some texture to it, which may not be appealing to some, but not that noticeable. It does require you to cut a larger hole, near 6.25" for the 4" port so if you are building your enclosure ahead of time, remember to allow enough room for the flange. Flange is much larger than it appears in photo.
Date published: 2009-08-10
Rated 4 out of 5 by from least amount of noise possibleI have used this product before on a sound quality system i used 2 in fact 1 for each 12 inch megaloud subwoofer and it was phenominal!!!!!!!!
Date published: 2009-06-27
Rated 5 out of 5 by from works every time.......I've used these ports a few time and they sound great. I install car audio and used to do slot port boxes, but now its areo's all day baby!!
Date published: 2009-06-10
Rated 3 out of 5 by from Cheap, solid, but uglyThis port tube is very solid, and I imagine it would work well. However, sine I am going to be veneering my subwoofer, I want something that looks classy. This does not. If you look at the picture, you can sort of see the front flange has this fake leather appearance embossed in the plastic. It is hideous. This might be a good choice if you are using a rear port, or don't care about looks.
Date published: 2009-04-25
Rated 5 out of 5 by from Solid ProductI was impressed by the quality of this tube. Very nice quality, sturdy, solid, and sounds great!
Date published: 2009-04-01
Rated 5 out of 5 by from A MUST HAVE!!This is well worth the money. The plastic is thin and feels flimsy at first. However, it is a non-issue considering the flares provide maximum airflow. I used a very thin cord of sealing putty to ensure that it was airtight. I also painted mine a textured silver color and then painted the outer rim metallic black. I even painted the inside part of the box black. The section of interior wall directly behind the flare. Otherwise you can see the MDF through the port. It looks SICK this way. Much, Much, Much better than a slotted port...go for it
Date published: 2009-03-26
Rated 5 out of 5 by from Qualtiy 4" port for less!Most 4" areo ports cost anywhere from $10-$20 dollars more. You can find them cheaper but they are not the quality of these I have purchased 4 so far and will be buying more!!!!!
Date published: 2009-03-05
Rated 5 out of 5 by from great productsthis is my first time using aero ports and im impress with them i can rally hear that my system is alittle bit louder to the ear and on the mic
Date published: 2009-02-19
Rated 5 out of 5 by from Good productCould have added the size of the mounting ring, it is about 6 1/2".
Date published: 2009-02-09
Rated 5 out of 5 by from Easy flaired portEasy to install. Just make sure that your openings are 6.25" in diameter.
Date published: 2009-01-27
Rated 5 out of 5 by from Great Product - Instant Bass UpgradeThis is an awesome port. It really gets rid of port noise, as compared to slot ports.The installation of this 4" port does take some effort to cut the 6.25" hole. I couldn't find a hole saw for this size, so I had to cut it with a jig saw. But the result is worth it.
Date published: 2009-01-09
Rated 5 out of 5 by from Great ProductLoved the ease of installation and performance. I would highly recommend the to anyone who is a serious builder.
Date published: 2009-01-04
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Product Q&A

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Precision Port 4" Flared Speaker Cabinet Port Tube Kit

can I set port length for this at 14" or is it just 17" long

Asked by: wayne4444444
This port can be cut to 14".
Answered by: MattP
Date published: 2015-07-06

What is the length? Thanks

Asked by: jonne
The overall length of this port is 17".
Answered by: MattP
Date published: 2015-07-06

If I see correctly, the full 17", port with flares actually accounts for 22", of port length? Just trying to plan ahead. Thanks.

Asked by: Orly
The total length of the port with flares is 17". The total useful length of the straight part of the port is roughly 12" because of the flares.
Answered by: MattP
Date published: 2015-07-06

I calculate I need a 4.129 in. straight length and 4 in. port. With inside and outside flares minimum length is 5 in. Do I use the inside flare (5 in.) or outside flare only with straight tube (4.129 in straight length)? Pros/cons of each please Thanks!

Asked by: TPK1
You can either couple the flares together without the tube for a total port length of ~5" and drop your tuning frequency very slightly, or not bother with the inside flare and add about 1-5/8" of tube to the outside flare to get closer to the desired length. Depending on the size of the woofer, not having the inside flare will hardly affect anything.
Answered by: MattP
Date published: 2015-07-06

do the flared ends add length? so if I need a 15" long port i'd cut the 17" long tube to 15" to make a 15" port or do the flared ends add length?

Asked by: ParkerN
Yes the flares do add usable length to the port. We recommend cutting the tube itself 5" shorter than the design length calls for for the same tuning frequency once the flares are added.
Answered by: MattP
Date published: 2015-07-06

I need a 10 inch long port can I use two  5 inch ports for the same results?

Asked by: jtwig
No, two ports that add up to 10" will not give you the same results as a single 10" long port. You can contact our tech support to model port dimensions and box volumes if necessary.
Answered by: MattP
Date published: 2015-07-06

How does the flare affect the overall port length. I know back in the day we used 0.5x the diameter for the length of the flared piece. For example, if using a 3" port, and plans called for a 15" port we would cut the tube to 12". Is that true here also?

Asked by: Neptunes
It really depends on the flare itself, but in this case that rule can apply without a problem.
Answered by: MattP
Date published: 2015-07-06

what is the displacement of your 4 inch diameter flared port tube,, I was going to put it in a subwoofer box an I need to know so I can calculate my internal volume

Asked by: bobby35
We can help calculate that for you. The displacement will depend on the length of the port. If used as the full 17 inch overall length, the displacement is 0.14 cubic feet.
Answered by: Chrisf
Date published: 2015-07-06

What difference does the inside flare make. Cause I can't use it in my situation. Unless I cut the port really short. And I do not want that. It's for a 18 so a lot of air will be moving.

Asked by: derek82
Not adding the rear flare could add slight chuffing or unwanted port noise but it will allow for a shorter port tube.
Answered by: MattP
Date published: 2015-07-06

how short can the tube be ?

Using the port calculator for my speaker cabinet project the difference is only one inch .Is this enough to attach the two flares to ?Is there a minimum tube size requirement to adequately attach the flares together with the pipe ?I can't go to a smaller port size
Asked by: Smokey Lynx
The shortest affective port length you can have is with both flares coupled together (excluding the tube completely) and this will result in a port length of roughly 3-1/2", not including the flared ends.
Answered by: MattP
Date published: 2015-07-06

Does a port always have to be inside the cabinet?

What I mean can I put a port outside rather than inside and sill function the same as if it were inside?
Asked by: VusstoppyPro
No the port does not need to be on the inside, it will do the same thing if it were on the outside of the cabinet.
Answered by: MattP
Date published: 2013-01-14

What glue to use besides PVC Primer/Cement?

I know the instruction say to use PVC Primer/Cement or ABS Cement, but is there something else that would prove to be just as good and a little easier to work with like rubber cement, gorilla glue, etc. Thanks.
Asked by: cnp112
Rubber cement or Gorilla glue will probably work but probably wont last very long. I didn't have any pvc glue so I used some glue for building model cars. Basically anything that will melt the plastic will work and last. Super glue might work well.
Answered by: Mseries
Date published: 2013-01-13

Can I extend this port kit to a longer length with 4" PVC Pipe from my local hardware store instead of buying the PSP-4TB plus the connecting rings.

Asked by: cnp112
Yes, this will work fine. However, it would be prudent to bring these flares with you when shopping for your PVC pipe. PVC wall thickness varies according to it's schedule rating, and 4" pipe does not have a have an inside, or outside diameter of 4", it's actually 4.5" outside. The schedule (wall thickness) then determines the inside diameter. Schedule 40 PVC has a wall thickness of just under a quarter of an inch (.237"), so it's inside diameter would be just over 4" (4.026"). That would be your best bet, but I can't definitively tell you that the port flares would fit on the PVC pipe.Another option would be black ABS pipe for a better aesthetic match. Use ABS cement if you use ABS pipe, and PVC cement if you use PVC.You can also buy PVC or ABS "elbows" so you can put bends in your port, allowing you to get more creative with your port placement, since it is so long.The real value of this kit is the flared ends which reduce port noise and turbulence. Whatever type of tube you put between them is inconsequential as long as it is sturdy and of the right length for your tuning.One last thought, you may want to consider using a smaller diameter port, as it will not need to be so long. Remember that the more volume your port takes up, the less useful volume your box has.Whatever you do, have fun!
Answered by: Travis Rysdam
Date published: 2012-12-06

what can i use to make this port 25 inches long

Asked by: andrewb
You could buy 2 kits and secure two lengths of tube together with a solid external collar brace to achieve the necessary legth. You could use some left over tube, slit it down one side, and secure it around the junction of the 2 pieces you are joining with ABS cement. You could even do that twice, one from the top, one from the bottom for a really secure hold.Though, honestly if your tuning requires such a long port length you may want to look at using a smaller diameter port in order to reduce the necessary port length. A 3" port would need to be much shorter to achieve the same tuning frequency.For example with a 1.5 cubic ft box and a desired 28Hz tuning a 4" dia. port needs to be 25.875" long. Whereas a 3" dia. port only needs to be 14" long to achieve the same 28 Hz tuning in the same box.
Answered by: Travis Rysdam
Date published: 2012-07-09

What is the "flare radius"?

I have a program (Flare-it) that tells me if I will have port noise. I'm trying to calculate the "flare radius".
Asked by: Ess OH ELL
7.250" OD according to the description. Radius is half that, 3.625"Flared ports don’t necessarily provide any advantage over straight tubes. What would make a difference is if you stuffed the tubes with soda straws to “columnate” the flow like a LASER or Vegas water-fountain nozzles.This WOULD reduce vortex effects but still may not make a noticeable difference. You would have to have expensive analyzing equipment to denote the actual effect.If someone were to give me some of these, I would whack off the front flare mostly, to keep the hole in the baffle smaller. Meanwhile I use PVC or ABS tubing as a default. They are cheap and you can make a "tunable port" by placing a smaller tube inside a larger tube to make a sliding port. Then glue or cut a new one to length. Keep the tunable one as a tool.
Answered by: Fanden
Date published: 2012-10-05

Is there a way I can assure the tube will be 16" long?

looking at 2 of these and the tubes needs to 16" long to tune my enclosure to 32 Hz i have 3 10's i am putting in a single enclosure
Asked by: careless
The quick answer to your question is...measure twice. The serious answer is...this kit comes with a 17" tube and two flared ends. Therefore you will need to only cut off an inch of the supplied 17" tube before permanently gluing the two flared ends to your newly created 16" tube.I hope that helps you.
Answered by: Anonymous
Date published: 2012-01-08

Does this kit come with the tube itself or just the post ends? What length tube?

Asked by: Vinnie
It comes with a tube and the ends. Usually the tube is 14-16"
Answered by: paragv
Date published: 2011-10-10

4" tube diameter? And is the max diameter really 7.25 in?

Asked by: Audiophile77
Yes 4" ID and 7.25" OD of the outside flare.
Answered by: mtg90
Date published: 2012-11-18

So when i cut the hole to install this port it should be 6 1/4" in diameter?

Asked by: nick23parker
Yes, this product requires a 6-1/4" cutout.
Answered by: RussR
Date published: 2015-12-28
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