Finalist Build With a Couple of Wrinkles

[cfbuck]

Staining Complete

I have finished the staining after many trials. It is as close as I can come to the furniture match. But it is interesting that the bookmatch stains differently on the two bookmatch sides. The leaves were opened face to face and then jointed as a bookmatch on each large side of the speaker. Visible in the photos, the stain took differently on the two leaves, one darker than the other. Anyone know why?

The bottom photo was taken with a combo of incandescent and fluorescent lighting. The first two used the same lighting and the camera flash and are closer to the actual apparent colour. Sorry, not an expert photographer.

The staining process used a honey amber aniline dye followed by a Georgian Brown aniline dye both purchased from Lee Valley. A couple of light wash coats of 1lb cut shellac was used to seal the dyes. Then two coats of Varathane Special Walnut Gel Stain was rubbed onto the surface. This coloured the open pores to the dark brown and eliminated the orange pores that were left from the aniline dyes.

I am in the process of applying General Finishes Enduro Water Base Urethane Gloss Finish. It will be rubbed out to a satin finish later.

[AdelaaR]

Looking good!

[cfbuck]

Been away for a two week vacation. Nothing happening re the finish yet. Foam ordered for the damping material.

[knowledgebass]

The nature of book-matching results in two pieces of wood with grain in opposing directions (~90° off). This results in the book matched pieces reflecting light slightly differently.

[cfbuck]

Finally Finalist Finished

Due to life obligations and attempting a new finish technique, I have taken four months to finish the speakers.

My son does a lot of woodworking and he has used a finish technique (from Fine Woodworking) which involves applying a lot of coats of waterborne poly and then using mechanical sanding and Mirka mesh and foam-backed sanding disks. After 10 coats, a sanding with 220 to level the finish, then applying four or more coats letting dry for 14 days and then progressively sanding with 320, 400, 500, 600, 800, 1000, 1500 and higher if a piano gloss is desired. It was a bad choice of finish for this oak which has deep cavities where the open grain dominates the surface.

I used 14 coats to attempt to fill up the open pore areas. It still wasn't enough and I burned through the finish and the stain trying too hard to attain a level surface. This required restaining the burned through area and then rebuilding the initial finish coat. After 24 coats and a couple of more burn throughs, I was able to level the finish. Won't use this method on oak again, but I will on close grained woods that are not stained. The method sounds laborious, but on flat surfaces, the mechanical sanding makes it go very quickly once the initial build of finish is done. The results, I think are very good.

Here are a few photos which I took in the shop. I can't get good results there. Whether it's the lighting or my photography I can't determine. But you should be able to see the resulting fine surface. The darker photos are with the camera flash and are not true to the colour. I stopped sanding with 1500 grit on the sides and 2000 on the front baffles for a semi-gloss finish. The poly is General Finishes Enduro. It is supposed to form a harder surface than the usual off the shelf waterbased polyurethanes.

[impala454]

Great job! :T

[cfbuck]

Back Tunnel Treatment

]I can't remember what I had intended to do with the rabbet at the tunnel exit. I think that I was going to have replaceable plugs or open rings to fit in the rabbet. I couldn't figure out a sophisticated method of holding either plug or ring onto the speaker. I have decided just to fit a wooden ring and glue it in the rabbet. Then I will turn a plug to fit the ring and seal the tunnel for the near wall configuration



So, I have turned a ring similar to the vent tube above the tunnel. It had to fit over the rabbet and glue to the inside of the MDF. One rabbet had a slightly larger diameter than the other, so the rings were not quite identical. this was caused by a slightly sloppy pin I use on the Jasper Jig. Since I am turning them, the size difference is not an issue.

I had the baffle cutouts in oak from the front woofers of these speakers and some other larger cherry cutouts from other speakers. The cherry was glued on top of the oak concentrically. The oak will be on the inside and glued to the MDF rabbet. The cherry will form the outer and larger portion of the ring. I painted the rings flat black to match the vent tube.

You may notice a slight defect on the rightmost ring edge at the bottom. That was actually a slice cut from the ring edge so that the ring would overlap the vent tube and fit flush to the speaker back. The two holes were too close to each other, necessitating that the ring overlap the vent tube.



Here is a photo of one ring installed with a foam plug inserted. I found that I could cut the foam very accurately with the bandsaw. The owner will have the choice of a foam plug or a sealed wooden plug. I hope that is what Jim intended.

[Jim Holtz]

Whatever works in your room.

I would suggest placing them 18" from the wall behind without any plug for the maiden voyage. The mid tunnel should be lined with 1" foam regardless of open or closed back. I like mine 6 1/2" and flush at the back of the mid tunnel in my room. I also taper the driver end of the foam at a 45 degree angle for a smooth sound wave transition.

I'm looking forward to hearing your thoughts about how they sound. ;b>

Jim

[cfbuck]

Whatever works in your room.

I would suggest placing them 18" from the wall behind without any plug for the maiden voyage. The mid tunnel should be lined with 1" foam regardless of open or closed back. I like mine 6 1/2" and flush at the back of the mid tunnel in my room. I also taper the driver end of the foam at a 45 degree angle for a smooth sound wave transition.

I'm looking forward to hearing your thoughts about how they sound. ;b>

Jim

Hi Jim,

If you look at the first photo in the post above yours, can see the tunnel with the foam installed. I have followed your advice but the foam stops .75" from the back of the speaker because I had to install a ring to cover the rabbet that I put in the tunnel at the back. But I think that will be close enough to your specifications. It is tapered at the driver end at 45 degrees and is 6.5" long. perhaps I should shorten in to 6"?

The speakers are intended for my brother-in-law and they will be mounted unconventionally close to the wall for the time being. Hence the need for the plug. Would you suggest a sealed plug rather than the foam, in this case? I have both.

I listened to them in my room, yesterday, sitting a bit high--26" off the floor. There was no plug installed. There is a small ss receiver there, a 30 wpc NAD 7030. My CD player was skipping around and causing some frustration at first. It was difficult to concentrate on the qualitites of the speakers with the skipping going on. But I don't think that 30 wpc can drive them to their capabilities.

To-day I dragged in a 120 wpc Leach. The CD player behaved. They opened up just fine--filled the 13' x 24' room. Image like crazy, very high accuracy, transparency, smooth transistion between the drivers, nice bass. I was impressed. More about this when the owner hears them.

Thanks Jim and Curt

[Jim Holtz]

Hi Fred,

The foam in the mid tunnel should be just fine. The foam can be adjusted for different rooms and placement. The purpose of telling what I did is to give a base line of sorts to start from. Once your brother-in-laws gets them positioned in his room, experiment with both the foam and solid rear plug. either way, the foam should stay in with the wood plug to prevent reflections.

Good feedback! It sounds like you're off to a good start with you're initial listening impressions.

BTW, your woodworking is superb! I wish I had your skills.

Jim

[benthe8track]

Those look fantastic!

[cfbuck]

Thanks benthetrack and impala454

[cfbuck]

The Tunnel Plugs

Here are the turned wooden plugs. I just used some pine and painted them black to match the rings. They are tapered and fit nicely into the ring.



If you look closely at the photo where they are standing on end, you will see a rabbet on the inner side of the top plug but on the bottom one, the window seal foam gasket is applied. This seals the tunnel quite well.



I have attached a knob in the centre to insert and remove them easily.

[cfbuck]

Owner's Comments for Jim and Curt

For Jim and Curt

The speakers are hooked up in my bedroom. To the Luxman - 33wpc a channel. It seems to be driving them fine, although, as you say, there is the impression they are champing at the bit. I will follow up with your suggestions..

Still listening, but the sound is fabulous. Lows and highs are quite amazing.. hearing things on cds I've had a long time that I've never heard before. The loudness button on the Luxman actually makes a big difference to the mid range, esp pop music... which leads me to think that a more powerful amp of the right sort will make a big difference. For classical, quite beautiful already. .. thrilling actually. Feel such gratitude.

The speakers require a bigger room, and so obviously I will have to move.

[Jim Holtz]

For Jim and Curt

The speakers are hooked up in my bedroom. To the Luxman - 33wpc a channel. It seems to be driving them fine, although, as you say, there is the impression they are champing at the bit. I will follow up with your suggestions..

Still listening, but the sound is fabulous. Lows and highs are quite amazing.. hearing things on cds I've had a long time that I've never heard before. The loudness button on the Luxman actually makes a big difference to the mid range, esp pop music... which leads me to think that a more powerful amp of the right sort will make a big difference. For classical, quite beautiful already. .. thrilling actually. Feel such gratitude.

The speakers require a bigger room, and so obviously I will have to move.

Awesome! :T I'm really pleased to hear that you're enjoying The Finalists and that the sound matches your fantastic cabinetry work. However, make no mistake, Curt is the one with the brains and is totally responsible for the sound quality you are hearing. I just do the heavy lifting.

PS: The more clean quality power you provide The Finalists the more you'll like them.

Jim