Pictures of speaker project so far; got a few questions

[ikonetic]

This is where I am at in my speaker build, These have a Dayton Esoteric 7" woofer, Neo 8 mid and Dayton AMT tweeter. You can see the installed xovers and I have padded with acoustic panel and strategic egg crate foam. They are ported with a 1" port. I have constructed the boxes out of 3/4 MDF and as soon as I reinstall the front and rear panels, I will sand them smooth and then I intend to veneer them using the iron on method of veneering. I have to fill the holes where the screws holding the panels and some small gaps on the edge where the panel do not quite match up by maybe a 32nd or less. I was wondering what would be the best thing to use to fill those holes and gaps. I have heard everything from Glue and sawdust mix to Joint compound. The joint compound would be easiest, but I would like to hear from some body who has tried this if possible. Also, can you fuse a speaker line so, if the wiring is wrong, it won't fry my amps or should I just buy a cheap amp to test them with?

[Pete Schumacher]

Re: Pictures of speaker project so far; got a few questions

This is where I am at in my speaker build, These have a Dayton Esoteric 7" woofer, Neo 8 mid and Dayton AMT tweeter. You can see the installed xovers and I have padded with acoustic panel and strategic egg crate foam. They are ported with a 1" port. I have constructed the boxes out of 3/4 MDF and as soon as I reinstall the front and rear panels, I will sand them smooth and then I intend to veneer them using the iron on method of veneering. I have to fill the holes where the screws holding the panels and some small gaps on the edge where the panel do not quite match up by maybe a 32nd or less. I was wondering what would be the best thing to use to fill those holes and gaps. I have heard everything from Glue and sawdust mix to Joint compound. The joint compound would be easiest, but I would like to hear from some body who has tried this if possible. Also, can you fuse a speaker line so, if the wiring is wrong, it won't fry my amps or should I just buy a cheap amp to test them with?

Bondo.

[chrisn]

Re: Pictures of speaker project so far; got a few questions

Bondo, spot putty, spackle, joint compound, all will do the job. If it's a really big chunk or large gap I'd lean towards bondo, the others are more practical for smaller blemishes. Wood glue, thinned with water, works well on the edges of MDF.

[thekorvers]

Re: Pictures of speaker project so far; got a few questions

Is that an error or are you seriously considering using a 1" port with a 7" driver?

[tomzarbo]

Re: Pictures of speaker project so far; got a few questions

Bondo would be the easiest next to joint compound... but I'd rather not use joint compound.

I've used sawdust from the base material and glue to fill holes/divots and it has worked well. The repair will shrink as the glue dries out or evaporates its water content, but if you overfill it, it should be fine. I've made plenty of repairs like this and since you are essentially using the base material as filler, it doesn't really show up later on under veneer. Do make sure you use enough glue if you use this method, if it's too dry, the repair may crumble.

The comment about a 1" diameter port is a valid concern, it looks like a red flag actually. Whatever box program you are using, check to see if there is a 'vent velocity' or 'port speed' tab. If the vent velocity is too fast then you will have some un-musical noises coming from the vent, commonly called "chuffing." I'd expect a 7' woofer to need at least a 1.5" diameter port if not 1 3/4" to 2". I know larger diam. ports tend to be a lot longer, but that's the trade-off unfortunately.

Your cabinets/crossovers look very nice, and it's obvious you've spent a lot of time planning things out, nice work!

TomZ

[Paul K.]

Re: Pictures of speaker project so far; got a few questions

I had the same question!
Paul

Is that an error or are you seriously considering using a 1" port with a 7" driver?

[ikonetic]

Re: Pictures of speaker project so far; got a few questions

1" is the best I could do due to port length.

[isaeagle4031]

Re: Pictures of speaker project so far; got a few questions

Even under moderate power, a 1" port is going to exhibit a lot of chuffing or port noise. Can you share your dimensions or sim?

[DanHine]

Re: Pictures of speaker project so far; got a few questions

1" is the best I could do due to port length.

Speaking from experience as someone who tried to get away with a port which was too small, you ARE going to wish you had figured out a different solution. I'd suggest waiting to seal everything up until you've exhausted every option on how to fit a larger port. Maybe a slot port running along the bottom?

[Face]

Re: Pictures of speaker project so far; got a few questions

Speaking from experience as someone who tried to get away with a port which was too small, you ARE going to wish you had figured out a different solution. I'd suggest waiting to seal everything up until you've exhausted every option on how to fit a larger port. Maybe a slot port running along the bottom?

Or rear mounted passive radiator(s).

[ikonetic]

Re: Pictures of speaker project so far; got a few questions

I will finish this build and test before I put on the veneer. If I have to enlarge the port, it will have to go directly behind the woofer, and I was trying to avoid that. As it is it is located up on top in back at the top of a chimney that has staggered eggcrate foam in it to break up the airflow. If you look at the pictures, the chimney is where the xovers are mounted, so there is a 90 there as well. Box size for the woofer is .6 cubic feet with a tuning freq of 37hz. 1" flare port I have says 2.58" for this.

[Chris Roemer]

Re: Pictures of speaker project so far; got a few questions

Most "typical" limit for port air velocity ( from WinISD at www.linearteam.org ) is Mach 0.15 (and MANY consider THAT too high).
Your 1"d port will be about double that, maybe Mach 0.30 or so. Not good. Even a generous roundover won't do much here.

I've heard Dayton's 6-1/2" "Classic" woofers chuff through a 2" id port (and YOUR woofer's got 65% more Xmax avail.).
MY BR-1 clones are in about 0.5cf, and I fit a 2-1/2"id x 14" long port in the box. Ran it right out the top (w/some hardware cloth on the bottom end so I can dump out any "stuff" that kids toss in there).