|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Re: 4Pi Rough concept [message #88191 is a reply to message #88161] |
Sat, 16 June 2018 22:04   |
ggnarley
Messages: 21
Registered: May 2018
Location: Ohio
|
Chancellor |
|
|
Installed cleats on back board of cabinet to guide brace going from front to back. Slightly tapered the front edge so it will funnel the brace into position. Will put two screws through back and into brace for extra support. On the front side of the brace I used some Kreg pocket screws.
Brace going from side to side is also held in place by pocket screws. Each brace is just a hair longer than needed to give a compression fit.
Port sides are 1/2 baltic birch I had lying around. Glued up port box separately on it's end and stapled with finish nails. After it dried I glued and screwed it to the front face, then added some 2 inch screws.
I'm on the fence with the black foam tape I used for sealing the speaker back. I screwed the back in while I was fitting the braces, and when I took the back off, the foam stayed about completely compressed. I guess I was expecting it to bounce back a little bit.
I have some black speaker grill from parts express and wanted to mock up what the final speaker would look like. Plan on wrapping 3 sides with the cloth. Tried some walnut and it was ok. Liked the maple pictured here a lot better. As of now, my plan is to build a solid 2" thick slab that overlaps a bit on all sides. I will recess the center around 3/4" so it stays in place and covers the top edges. Will oversize a bit to allow for seasonal wood movement. I may also run a maple board about 5" to 6" down the back of each side as pictured. It breaks up the blockiness of the mass. (Hat tip to Josh).
Here is the lumber I will use. It is the last of some maple and walnut I got about 20 years ago. My wife and I refer to that time as BC - (before children). Anyway, still working out exact details of how to attach everything. Noodling a couple ways to be able to remove the grill without too much hassle.
I would like to add some extra protection to the woofer. First,
these may be moved and used for various school, church family functions. Second, our house is a bit crazy at times. We have gone through fazes of inside roller bladeing, skateboarding football and soccer. I've looked at various official metal type speaker grills, and even forming my own from hardware cloth. It doesn't have to be pretty as it will be covered by the grill cloth. Then I saw our pizza screen used for baking pizzas and thought it might work. I can get a 15" one for about 3 dollars. If it doesn't work, we use it for cooking. If it does, I will change the speaker name to pizza pi. 
Paul
|
|
|
|
| Re: 4Pi Rough concept [message #88245 is a reply to message #88191] |
Sun, 24 June 2018 20:59 |
ggnarley
Messages: 21
Registered: May 2018
Location: Ohio
|
Chancellor |
|
|
The goodies from Wayne came in. I purchased the x-overs and wave guides. I only have one set of drivers (JBL 2226 Midbase and B&C 250 cd) at this point, so time to get one up and going.
Placed the waveguide in cutout to mark for mounting holes. Drilled and inserted t-nuts. Somehow I got one of the holes a hair off so will have to pull t-nut, ream hole and reinstall. But that can wait.
Wayne suggests putting something under x-over to keep it from vibrating. Took a tour of our basement and found and old snow sled that would work great. It is just a thin piece of plastic laminated to 1/8 foam.
Measured and cut with utility knife and it worked great. Had to enlarge x-over holes just a bit to allow screws through. Mounted it and resistor to bottom of cabinet.
Have been doing a little more electrical work than normal lately. Finally got some crimpers to make electrical connections and wishing I had bought them years ago. They make really strong professional looking connections. I crimped all the wires for one speaker. I would think spade lugs would give a better connection, but both drivers had only spring loaded connections, so I used those.
Time to listen to some music now. Still don't have insulation in place, but want to hear how it sounds. Got my son to help carry it into the living room and hook it up. They are heavy!
WOW!! I have the 4pi on one one channel and my existing bookshelf speaker on the other channel. Sounds like there is a pillow over the bookshelf speaker compared to the pi. The two things that stick out to me right away are the vocals and percussion. Etta James "At Last" sounded like she was in the room. This is even with just one channel. Percussion was equally impressive. Night and day difference from the bookshelf speaker.
Wife and son also really liked the sound. My younger son then wanted to play something he likes that was only on spotify. It was some current pop song, but you could immediately tell how compressed it was. I stuck to CD rips for the rest of the listening session. Played classic rock, blues, classical, vocals and it was all like listening to the music the first time.
Currently I am running an old NAD 3020 amp I got in college many many moons ago. Only has 20 watts and can barely drive the book shelf speakers to a somewhat loud level. At 1 watt my one 4pi sounds much better. Played a few songs at about 10 watts when rest of family was away and it sounded incredible.
It will be hard to unhook this speaker to finish it up.
Paul
|
|
|
|
|
|
Posting Rules
Members
Search
Help
Register
Login
Get a T-Shirt!
