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Pensil Pics, lets show 'em!

Just moved into a townhouse after being relocated for work and got the setup mostly done. Still need to build a center channel when the design is done for an A12 or A10.2. I spread the speakers another 2" wider and 1" out on each side and its made a big difference and is throwing a better phantom center. Yes I know the drivers aren't even; the cabinet on the left is correct the one on the right is too high. Stupid person constructing them measured wrong ;) OOPS!

CRW_1133_RJ-medium.jpg


CRW_1145_RJ-medium.jpg
 
that'll disappear once the grilles are on


is the the final location? that would be helpful to know when it comes time to design the center channel enclosure

I'm going to rout out the wrong front panel and build a new one and glue it in. Shouldn't be TOO tough I hope! LOL!

You mean is the TV in the final location? No. I'm actually going to build a mount that brings the TV to the front and tilts it down a little. I'm hoping to make the center shallow enough to be able to mount below the TV. Could look kinda cool I think.

Scott
 
Well, a week later, they are finished (almost). I still have to secure the bases and install carpet spikes...but I wasn't going to let that stop me from listening to them last night.

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Cabinets were built from 3/4" birch ply from Home Depot. Mitred joints were used to save on veneer. The only face that has veneer is the front, which is birch from Parts Express. 2 coats of Danish oil dark walnut stain. 2 coats of wipe-on poly. One coat of finishing wax and buffed to a semi-glossy finish.

I still don't have the polyfill right. They've got a tad too much bass on certain songs (not necessarily a bad thing) which is usually OK, but sometimes can be distracting. I'm also experimenting with room placement. They will be in the corners, but how far in, and how much toe I use is to be determined.
 
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chuyler - play with getting them as far out from the corners boundaries as much as can - with the driver's BSC compensation and the excellent performance of Scott's design, these will likely need far less "help" than you're used to.

I'd be vewy vewy careful with spikes on the carpet - after damaging both deep pile carpet (mine) and edge-grain solid fir floor ( Dave's) I've long since eschewed spikes altogether in favour of granite slabs on carpets and felt slider pads on vinyl/laminate and hardwood floors.

nice work, and now just enjoy the damned things
 
Well, a week later, they are finished (almost). I still have to secure the bases and install carpet spikes...but I wasn't going to let that stop me from listening to them last night.

An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.


Cabinets were built from 3/4" birch ply from Home Depot. Mitred joints were used to save on veneer. The only face that has veneer is the front, which is birch from Parts Express. 2 coats of Danish oil dark walnut stain. 2 coats of wipe-on poly. One coat of finishing wax and buffed to a semi-glossy finish.

I still don't have the polyfill right. They've got a tad too much bass on certain songs (not necessarily a bad thing) which is usually OK, but sometimes can be distracting. I'm also experimenting with room placement. They will be in the corners, but how far in, and how much toe I use is to be determined.

Wow, those are nice. I am considering the pencils and thanks for the tip on the mitered joints as I am looking at the same ply you made yours out of and was thinking I was going to have to clue on a solid wood trim edge. What type of joint or means of securing them did you use? Thanks
 
chuyler - play with getting them as far out from the corners boundaries as much as can - with the driver's BSC compensation and the excellent performance of Scott's design, these will likely need far less "help" than you're used to.
I've noticed. They sounded best in the middle of the room...but sadly, they've got to be pushed back a little for the WAF.

I'd be vewy vewy careful with spikes on the carpet - after damaging both deep pile carpet (mine) and edge-grain solid fir floor ( Dave's) I've long since eschewed spikes altogether in favour of granite slabs on carpets and felt slider pads on vinyl/laminate and hardwood floors.
Well the last set of speakers only moved when it was time to vacuum, and even then I usually just vacuumed around them. So once I get the right spot, they'll stay. The carpet came with the house and will be replaced eventually (we're just letting the pets destroy it first).
 
Wow, those are nice. I am considering the pencils and thanks for the tip on the mitered joints as I am looking at the same ply you made yours out of and was thinking I was going to have to clue on a solid wood trim edge. What type of joint or means of securing them did you use? Thanks
Some build pics are a page or two back in this thread. Mitred joints for all the sides, then butt join for putting the front on. Wood glue was used all around, no nails or screws...except for the back panel which is removable.

You've got to be very careful with the plywood as it comes with a very thin veneer that can easily chip. I cut the pieces to the outer dimensions then mitered them afterward. Use scrap wood beforehand to make sure the table saw is set precisely. I had a few chips but I filled them with stainable wood putty. I could point out the spots to the average viewer, but standing a food a way you wouldn't notice. My woodworking skills on a scale of 1 to 10 are about a 6 or 7...but I know enough about hiding mistakes that the final product is passable.
 
chuyler - play with getting them as far out from the corners boundaries as much as can - with the driver's BSC compensation and the excellent performance of Scott's design, these will likely need far less "help" than you're used to.

I'd be vewy vewy careful with spikes on the carpet - after damaging both deep pile carpet (mine) and edge-grain solid fir floor ( Dave's) I've long since eschewed spikes altogether in favour of granite slabs on carpets and felt slider pads on vinyl/laminate and hardwood floors.

nice work, and now just enjoy the damned things

(This is probably a bit off-topic, but here we go anyway....)

Proper room placement can reinforce bass particularly in the very low regions. Allen Perkins has an interesting paper (re-penned by Joachim Gerhard in 2009) on speaker placement that I think applies very well to single-driver systems. I have not spoken with either Allen or Joachim regarding changes to Allen's original work.

http://www.immediasound.com/Speaker%20set-up%202009.pdf

This might not be the end-all / do-all for speaker set-up, but it might be worth a try or even a starting point for some. In my experimenting, the soundstage and imaging improved by moving away from the back wall a bit, but the boundary effect bass was reduced. It made for an interesting experiment in system performance tuning. YMMV.
 
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Alpair 7 is the 4" fullrange driver with 20w nominal power. Are you sure they can handle the 25w / side.

I use a pair of Herron M-150 mono amps on a pair of bipole CAA FR125SRs (that's 150 watts on each speaker). It's not the amount of power that's available, it's how its applied and the frequency used. 5 watts at 500hz is a lot different than 2 watts at 20hz.
 
In the Alpair 7 thread it is noted that driver height is important in the cabinet design. Would it then be unreasonable to expect a Pensil 10.2 cabinet with the same internal volume and vent dimensions to perform less successfully if it were taller but less deep?

The reason I ask is that, like to individual making comment on the Alpair 7 thread, I prefer a driver that is quite a bit higher than the various Pensil designs call for. My personal preference is for midrange drivers to be between ~ 40" / 1 meter and 50" / 1.25 meters above the floor.