First time builder- micro Fonken

scooterdad

Member
2008-01-23 1:29 pm
Hello,

I am new to the forum, and I thank many of you for teaching me a lot already through past discussions. I am attempting to build the microFonkens (thank you Dave for kindly supplying the plans!) with the FF85 K drivers.

I plan to use these as a computer/nearfield set up at my desk at work. They will come reasonably close to the hard drive on my iMac, and will be paired with an inexpensive T amp(Sonic Impact Gen 2) at least to start. I had a few questions.. hoping for some help.

1. Do I need to worry too much about my computer hard drive with the unshielded FF85K?

2. Any recommendations for mounting the drivers to the cabinet? Do I need to use some sort of tape/sealant/foam?

3. I am using baltic birch plywood 1/2 inch, and my woodworking skills are pretty rudimentary. I plan on painting the speakers some version of black to hide my mistakes. Any suggestions for an easy black finish, preferably with non-toxic or low toxicity paint?

Thanks for your help! I will add photos and listening impressions when done.
 
scooterdad said:

I plan on painting the speakers some version of black to hide my mistakes. Any suggestions for an easy black finish, preferably with non-toxic or low toxicity paint?

This could quite possibly be the worst color choice to cover a mistake. Have you ever noticed how dirty a black car looks?

I'd suggest a dull grey, or a nice dark stain. Black is pretty hard to get right, and involves a lot of sanding.

Good luck on the build!
 
Speakers and hard drives

With a little looksee around the interwebs, It seems that it should be no problem. the driver magnets will have to get through the shielding of the hard drive. Then overcome the really strong magnets in the hard drive themselves.

Here is a page that addresses it somewhat. http://www.dansdata.com/gz009.htm

Here's a pic of a pair of surplus hard drive magnets lifting a 50lb weight. http://www.wondermagnet.com/item2demo.html

Can the FF85K lift 50lbs? :)
 
scooterdad said:
Hello,

I am new to the forum, and I thank many of you for teaching me a lot already through past discussions. I am attempting to build the microFonkens (thank you Dave for kindly supplying the plans!) with the FF85 K drivers.

I plan to use these as a computer/nearfield set up at my desk at work. They will come reasonably close to the hard drive on my iMac, and will be paired with an inexpensive T amp(Sonic Impact Gen 2) at least to start. I had a few questions.. hoping for some help.

1. Do I need to worry too much about my computer hard drive with the unshielded FF85K?

2. Any recommendations for mounting the drivers to the cabinet? Do I need to use some sort of tape/sealant/foam?

3. I am using baltic birch plywood 1/2 inch, and my woodworking skills are pretty rudimentary. I plan on painting the speakers some version of black to hide my mistakes. Any suggestions for an easy black finish, preferably with non-toxic or low toxicity paint?

Thanks for your help! I will add photos and listening impressions when done.



1) unless they're sitting right on top of the drive, I'd think an older CRT monitor would notice the flux more. Although that is a good question for anyone using an iMac, or external backup drive.

2) the stock Fostex screws (Phillips drive) will certainly work, but I prefer #6x 1/2" pan or button head square head screw.
If your driver hole is snug, the stock (very thin) gasket is adequate

3) For a tolerable black finish on BB, I use the following technique:

Fill exposed edge plys and minor chips with DAP or equivalent latex based spackle;
Sand with 180-220 G;
2 coats shellac based sealer stain hider (Zinsser BIN), sanding between coats with 220G;
3 coats of Painter's Choice semi-gloss/satin acrylic latex paint, applied with a short nap fabric roller. Black, or for that matter white or primary red/yellow isn't so much the issue, as is attempting a gloss finish, particularly on plywood. Provided you don't have ugly knots, stains or patches on the veneered panels, there's a lot to recommend a clear or lightly tinted top coat, such as:

http://img378.imageshack.us/img378/9417/img0968hu1.jpg
 

ronc

Member
2003-03-08 2:22 pm
I am just too intregrated into industry. About the last thing i consider is appearence, if ever.
1. Will it work according to the requirements.
2. Is it cost effective.
3. Does it require trained techs.(Simplicity)
4. Will it be reliable.
.
.
.
100 . What is the appearence.

ron
 
Thanks for all the helpful suggestions. As to finishing, I guess I'll try sanding a lot and see what happens before I decide anything. Easier to paint later than to regret painting and want a more natural finish.

I did come across this and was intrigued trying to match the iMac's style.

http://www.liquidstainlesssteel.com/

My guess, though, is that this finish could look particularly bad if done improperly. Plus it will be way more expensive than other options.
 
scooterdad said:
Thanks for all the helpful suggestions. As to finishing, I guess I'll try sanding a lot and see what happens before I decide anything. Easier to paint later than to regret painting and want a more natural finish.

I did come across this and was intrigued trying to match the iMac's style.

http://www.liquidstainlesssteel.com/

My guess, though, is that this finish could look particularly bad if done improperly. Plus it will be way more expensive than other options.


smallest quantity available is "craft kit" 4sq ft = $12.

I'd imagine if your prep wasn't perfect, you could kiss the boxes goodbye.
 
ronc said:
I am just too intregrated into industry. About the last thing i consider is appearence, if ever.
1. Will it work according to the requirements.
2. Is it cost effective.
3. Does it require trained techs.(Simplicity)
4. Will it be reliable.
.
.
.
100 . What is the appearence.

ron


Fair enough Ron - since I rely on boffins* like yourself and Scott / Dave to get the design right, I can concentrate on making them pretty enough that my wife won't throw them out of her living room

*I heard that term used on a radio interview the other day, and couldn't help myself - although you're not restricted to just slide-rules or mechanical calculators these days, the image just made me smile
 
Well, my build is coming along slowly. I received the drivers today... hefty little suckers for their size! I also ordered binding posts that were too short. Live and learn I guess

Is it critical to recess the driver into the baffle? Is this important for sound quality or more for aesthetics? I don't think I have the proper tool to do this part correctly ( a router?) The brace that is supposed to touch the back of the driver isn't close on my box. I haven't glued that piece in yet so I can always cut a bigger brace piece if the driver is ok sitting on the surface rather than recessed. Any advice appreciated.
 
scooterdad said:
Is it critical to recess the driver into the baffle? Is this important for sound quality or more for aesthetics? I don't think I have the proper tool to do this part correctly ( a router?) The brace that is supposed to touch the back of the driver isn't close on my box. I haven't glued that piece in yet so I can always cut a bigger brace piece if the driver is ok sitting on the surface rather than recessed. Any advice appreciated.

Flush mounting the driver should make a difference, We did do the 1st 2 pair without a rebate and they sound fantastic (no chance to get at the CNC). The brace should be firm against the magnet, but not so much as to strain.

dave