PDA

View Full Version : 4345 duct tubes



quindecima
12-19-2015, 11:42 PM
What have you guys that DIY with 4345's use for the duct tubs? I did a search and couldn't come up with anything.

tjm001
12-20-2015, 08:58 AM
What have you guys that DIY with 4345's use for the duct tubs? I did a search and couldn't come up with anything.

Assuming they are 4 inch diameter as my L300 boxes I have found the thin wall PVC drainage pipe sold at Lowes works perfect. It's like $10 for a 10 foot length. The outside diameter is exactly 4 inches and is a tight fit when tapped with a mallet into a accurately cut (with a router jig) hole. You then use the strong stick hot glue on the inside of the baffle to permanently hold them in place. You have to paint the inside with special paint for plastic. Use KRYLON FUSION paint. It is made just for plastic. I used flat black in my situation. I think once they are painted with this paint as a primer you could then use a normal paint on top of it of your choice of color if different.

Tom

http://www.krylon.com/products/fusion-for-plastic/

quindecima
12-20-2015, 10:40 AM
I thought about using that stuff but the ID of the tube is 4 in. I don't know if it could possibly make that much of a difference. I believe that JBL just used cardboard (gasp) when they made them.

tjm001
12-20-2015, 11:09 AM
I thought about using that stuff but the ID of the tube is 4 in. I don't know if it could possibly make that much of a difference. I believe that JBL just used cardboard (gasp) when they made them.

Yes, you are correct. I incorrectly said OD was 4 inches. I reviewed my notes and the diameter of the holes I made was 4 3/16. I do remember now of having to run a drum sander on the end of a drill around the inside of the holes just a few times to get the good tight fit that I described. It really worked good.

Tom68847

quindecima
12-20-2015, 12:00 PM
I think I am going to get some heavy duty poster board and a 4in. form and see if I can roll my own.

BMWCCA
12-20-2015, 12:11 PM
Plenty available online in large quantity. I'd check at a craft store or packaging store.

http://www.uline.com/grp_74_heavyduty/Heavy-Duty-Kraft-Tubes

http://www.yazoomills.com/mailing-tubes/heavy-duty-kraft.aspx

I would assume the cardboard would offer less possibility of undesirable resonance than the plastic pipe, and it is what JBL uses.

quindecima
12-20-2015, 12:54 PM
Much Grass :bouncy:

just4kinks
12-21-2015, 11:03 PM
I used 4" ABS from Home Depot, press fit into a precisely routed hole. The hole was stepped so that you can't see the cut edge of the ABS from the front of the speaker.

No glue, I wanted the flexibility to retune the cabinets. They're tight, not going anywhere.

RedCoat23
12-22-2015, 02:09 PM
I also used 4 inch ABS from home depot in my B460 clone
Inside diameter is 4 inches. It does indeed 'ring' a little. I stepped the cut in the baffle so it seats at the bottom and used resin to fix. To stop, or at least limit the 'ringing' I wrapped the pipe in a dynamat type material called FatMat essentially the same but much cheaper. When snapping my fingers at the end of the tube, pre and post wrapping you can tell that it largely stopped the resonance.

ABS Pipe (http://www.homedepot.com/p/Unbranded-4-in-x-10-ft-PVC-Sch-40-DWV-Plain-End-Pipe-531103/100156409)

Acoustic deadening (http://www.amazon.com/gp/product/B003TUNRGM)

Had I done a bit more due diligence I would have probably gone the cardboard tube route in hindsight just for ease of use.

quindecima
12-22-2015, 02:22 PM
I can get the heavy duty Kraft tubes online, just have to get more than I need but if anybody needs some I will have them, Got my speaker labels from SPEAKERDAVE today very, very nice indeed. I'm going to get the plywood tomorrow and start making them into sawdust.

quindecima
12-24-2015, 05:20 PM
I have 7 extra tubes 4in. I.D. X .150 wall. Brown paper. I had to order 10 to get what I wanted so if anybody needs some I've got them. they are 20in. long

gcarlberg
12-25-2015, 09:14 AM
For whats its worth;

At the 2nd Heritage Awards Dinner, Greg Timbers mention he would use flared ports if one were making mods to a 4345.

Merry Christmas,
george