KLF-10 into Center Channel

[Mlstrass]

I know a few on here have converted a KLF10 or 30 into a center channel speaker. I didn't find much doing a search so I'm hoping someone will respond here. I just picked up a single KLF-10 from e-bay for a good price with the sole purpose of making it a center channel.

What is involved in removing the front panel?

What did you do for video shielding?

I know it wont' be the same as HornEd's KLF-30 CC, but it should be an improvement over my C7, besides it was too cheap to pass up.

Any tips/advice would be GREATLY appreciated....Mike

This message has been edited by Mlstrass on 04-05-2002 at 02:31 PM

[HornEd]

Mlstrass, congratulations on joining the "Sensible Center Club"... and converting a KLF-10 is even easier than a KLF-30 (one less horn cut-out to make)! The best way I have found is to buy a piece of MDF... I prefer the 3/4" at Lowes to the current MDF at Home Depot... but either will work.

CAUTION: MDF dust is very fine... you should use at least an inexpensive dust mask to protect your lungs and eyewear to protect your eyes.

The first step is to remove the grill and take out the speakers. They are mounted with screws. Detach the positive and negative wires and use masking tape and a pen to label them. The wires will fit the new speaker positions without a problem. My technique uses the old motorboard as a template to make a new one.

the motorboard is attached with Liquid Nails to the speaker cabinet. I use a rubber mallet called a "Dead Head" (it bounces less thereby putting more force to the task at hand) and hit the motorboard along the edges by reaching into the speaker holes. Try not to mar the edge of the speaker cabinet by prying. With patient whacking... the motorboard should come out in one piece. If it does break, you can still use it as a template.

Mark the center of the motorboard on the horn end.

Lay the MDF on a flat surface and use the motorboard as a template and trace around the outside. If you use the two good edges of the MDF for one side and the bottom. Mark at one edge the center of the MDF's longest side.

Line up the vertical center mark on the old motorboard with the horizontal center mark on the MDF. Slide the motorboard so that the edge is even with the edge of the MDF. Use a carpenter's square (or the equivalent) to be sure that the motorboard/template is square... then trace the inside of the horn cutout.

Next, draw a line on the MDF 2½" from each side of the horn cutout. Lay the motorboard/template atop the MDF as you did to trace its outline. Slide the motorboard/template horizontally until the inside edge of the mark (that is 2½" from the horn cutout trace) and trace the cutout for the first woofer. Then slide it further to trace the cutout for the second woofer.

Using a compass, trace a line 3/4" outside of all the marks for the speaker cutouts. This mark will be the outer limits of a 1/4" deep router run that will hold the woofers by their flanges.

Cut out the cutouts. Rout out the flange areas. At this point you may want to make the holes for the Klipsch method of holding on the grilles. These ball type grille holders may be purchased by calling 1 800 KLIPSCH and ask for Trey. You will have to use a special drill bit to match the factory's flat bottom to the hole... or just use a regular bit and chisel it somewhat flat. Or, you can just use some industrial strength Velcro from a craft store.

When all the cutting is done, wipe the MDF down with a tack rag (just want to get the fine dust off of it) and spray paint it with several thin coats of flat black. Allow sufficient time to dry between coats. This protects the MDF and cuts down reflections. The factory applies many coats.

Lay down a continuous (unbroken) bead of "Liquid Nails" on the lip of the cabinet. The intent is to have the liquid nails form a barrier to preclude air from escaping from the sides and making "embarrassing" noises in the middle of your music. Lay the painted new motorboard in the cabinet. I make it a press fit... but that is probably tighter than necessary.

Re-attach the appropriate speaker wires to the speakers. Laying each speaker in its appreciate cutout and screw them down. (I usually put the speakers in first, line them up neatly... and trace the openings in the speaker flanges on the new motorboard. I then drill pilot holes to facilitate mounting the speakers (motors to the engineers).

Put the grille on, put it atop your TV (if you can) and tilt it slightly forward aiming at a head in the sweet spot.

I did this in a hurry, so feel free to ask questions. -HornEd

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Photo update soon! -HornEd

This message has been edited by HornEd on 04-13-2002 at 08:53 AM

[Mlstrass]

HornEd,

Thanks soooo much for the "Legendary" advice!!!

I'm almost done building my DIY sonosub, so I'm VERY versed on the ins/outs of MDF and routing. Should be a piece of cake.

One more question: what about shielding, as I'm putting this on a 36" tube TV. Did you use bucking magnets or shielding cups??

Thanks again...Mike

P.S. Also have a bid going on a pair of 20's to replace my 10's as surrounds.

[HornEd]

Neither, the KLF-30 Center is atop a 65" Mitsubishi RPHD and the distance to where the sensitive part of the TV is makes shielding unnecessary. However, I suspect for your application, bucking magnets should do the trick. A thin piece of low carbon sheet metal interposed between the TV and the magnets can also help.

I am somewhat busy this evening and have not had a chance to proof my earlier post. Basically, you mount the woofers on either side of the Horn... that keeps the sound properly anchored to the screen and seems to help with speech intelligibility.

I'll try to get back to this as soon as I am free. -HornEd

[Mlstrass]

Thanks again HornEd. I had planned on ordering the bucking magnets.

I'll have to look into getting a piece of low carbon sheet metal. Would that be like roof flashing do you know? Something I can get at the local Home Depot?

[Mlstrass]

One more question: should the horn be vertical or horizontal on the motorboard? At first I was going to do it vertical like the C7, but I see your 30 is horizontal, and also read that the C7 would have better dispersion with a horizontal horn.

What do you think? Thanks again...Mike

[HornEd]

Mlstrass, my intent was to make the "KLF-30 Center" sound as much like a floor standing KLF-30... and so I kept the horn orientation consistent. There is however, a slight shift in timbre probably caused by the change in proximity of the floor.

Most sheet metal is low carbon steel but if you check with a sheet metal shop you may be able to get some "ultra low carbon" steel that will be better for your shielding purposes.

Keep up the good work... especially the thinking part! -HornED

[Mlstrass]

KLF-10 arrived today, so tonight it's surgery time!!

Been thinking again (can be dangerous) and am considering mounting the horn vertically like the C7.

Just wondering if mounting it horizontally might actually spread the soundstage too much and bleed over the L&R mains. Or is a wider dispersion more desireable? For now it'll be sitting atop a 36" TV, probably a 57" WS in the future. Viewing/listening distance is about 10' away.

Any opinions on this??

P.S. Amp for DIY sub is shipping today. Pics to come...

[boa12]

m, guess that depends on your situation, but i would think having it verticle (as klipsch designed it) is best for that very reason - minimal bleed over. jmo.

verticle works great for me, but then again I don't have the physical seperation i'd like between the mains (space limits).

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My Home Systems Page

[Mlstrass]

boa12,

Thanks for the feedback. Always nice to hear someone else's thoughts to help keep me on track. I'm going with the vertical mounting like the C7.

Front baffle is out and I'm scraping out the old glue. Will be making some MDF dust soon.

Had a problem with the X-over and posted about that in another thread.....Mike

[Mlstrass]

I screwed up the first board on the last cut, router guide came loose....not fun.

Ended up making another one that came out nice. I decided to go with a horizontal mount for the horn: one because it was easier to make and also when I get a dedicated HT I'll be able to move the mains apart and will probably like the wider soundstage.

Painted the board "hammertone silver" and it came out VERY nice. Almost hate to put a grill on it. Speaker is Mahogony, but has some dents/dings on all the corners, so I'll probably end up fixing those and painting it black to match the 30's.

Of course now I'm on the look-out for a 20/30 to convert to a center. Does the madness ever end

[montigue]

Ed if your reading this, I hope that maybe you can give me some advise. I was thinking about making a center channel out of a KG 4.2. Although the problem is that the 4.2 only has one 10" driver and one 10" passive radiator.

Can this be done with a KG series speaker and sound right?

Monty

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Klipsch 5.2 mains

Klipsch 4.2 rears

Klipsch KLF C-7 center

Mitsubishi 55" HD widescreen tv

Toshiba pro scan DVD audio player

Sony Hi-Fi VCR player

Harman Kardon AVR 65 receiver

SVS 20/39 subwoofer w/Samsom S1000 amp

[HornEd]

Mlstrass, in the centers I have made I rotate the horn so that it has the same relationship with the room that the vertical standing Mains have. Remember, we are trying to preserve the timbre by making the horizontal speaker as much like Mains as possible!

Question... Won't the Hammered Silver paint job reflect through the grille?

Monty, I think you can do it by balancing the horn and woofer in the middle (to keep sound anchored properly to picture action) and then cut out a hole for the passive radiator on the other side of the horn. That should do the trick. -HornED

This message has been edited by HornEd on 04-13-2002 at 03:06 AM

[HornEd]

Mlstrass, you seem to be making good time on your center project. I have had a surprising number of requests on how to do it... so I have a favor to ask given your degree of woodworking skill. I would like to streamline my instruction set so that I can respond to center conversion requests with an email. So, I would appreciate some DIY input from your experience.

Such as:

1. Once you got into the project, did you find the outline I gave you helpful?

2. Did you have any difficulty tapping out the motorboard?

3. Did you take photos while you worked?

4. Did you find using the old motorboard as a template a workable strategy.

5. What tools did you use.

6. What surprise "sticking points" did you find?

7. What steps or warnings would you add to benefit the average DIY.

Mlstrass, thanks in advance for any insights you may share. For the above set of tips, the assumption in my advice was that you are a competent woodworker equal to the task at hand. I am hesitant to encourage people not used to precision cutting and the use of routers... but to my mind the process of converting center speakers is not very difficult... particularly when you don't lose a router guide!

As a general comment, I might add that changing Klipsch speakers for an altered use goes against my grain and respect for Klipsch engineering. However, the evolvement of mixing trends for HT, and to a lesser degree, multi-channel music, to the point where having a horizontal center that is the near-equal to one's Mains has become IMHO far more important than most people realize.

Of course, Klipsch might have a marketing dilemma if they tried to carry a horizontal version of their most popular Mains in this era of WAF fed "Twiggy" speaker trend. In all due respect, PWK was my inspiration for the KLF-30 Center... it doesn't take long listening to a pair of Khorns with a Belle in the center to realize that a robust center creates a world of difference.

Now, if only we could come up with a "bigger is fashionable" rationale to go along with the audio truth that "bigger is better" at center. Hey, it worked for the NFL! -HornED

This message has been edited by HornEd on 04-13-2002 at 09:52 AM

[Mlstrass]

HornEd,

After thinking it over the horizontal mounting of the horn makes more sense and you second that opinion, so I feel good about that decision.

Never thought about the silver color showing through the grill, but it looks SO good that I'll probably leave the grill off.

Now to answer your questions:

1. Once you got into the project, did you find the outline I gave you helpful? Yes it was pretty straight-forward, although I mainly was concerned with how to remove the original baffle as I wasn't sure how it was attached.

2. Did you have any difficulty tapping out the motorboard? Ended up using a 2# hand-held sledge hammer. Somebody at the Klipsch plant was VERY generous with the glue in a few places!

3. Did you take photos while you worked? Never gave it a thought, but will if/when I do a KLF-20 CC....

4. Did you find using the old motorboard as a template a workable strategy. Unfortunately the old motorboard came out in 2-3 pieces due to the massive amounts of glue in certain areas, otherwise that's a great tip.

5. What tools did you use. Bosch plunge router, 3/4" straight bit, tape measure, cordless drill/bits, 1/8" pegboard for homemade circle jig, Skilsaw for horn cutout, putty knife to remove the old glue. That's about it.

6. What surprise "sticking points" did you find? Only surprise was a broken cross-over that happened during shipping. ReturnBuy is reimbursing me for it. Conversion process is VERY simple. I am still not sure about the foam that was behind the speakers though. In the original configuration it was behind the horn and top woofer, not sure were I'll put it now. Actually I have 3 pieces so I'll probably put one behind each speaker. Also wonder if the port needs to be moved as it's pretty much behind one of the woofers now.

7. What steps or warnings would you add to benefit the average DIY. You can drill the grill mounting holes all the way through on the old board and use them as a template for the holes in the new board. Route the flushmount's first, then cut the holes out, that way you don't need a rabitting bit.

Seeing as C7's are still going for around $325 on ebay, and you can pick up scratch & dent KLF-10's for around $150 or less I think that all Legend owners should give this a try. Only looking at about $20 for the MDF and about $75 for the magnets (if putting on a regular TV) and you can usually borrow the tools you don't have. Probably looking at about 4-5 hours labor time.

Over-all it's very simple and should sound great. Just waiting on the bucking magnets/cross-over and we'll see how it sounds. Should be up and running by the weekend. Happy listening...Mike

This message has been edited by Mlstrass on 04-15-2002 at 10:33 PM

[boa12]

m, congrats on the new klf-10hec. guess we now have a case against klipsch using too much glue.

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My Home Systems Page

[Mlstrass]

boa12,

Only problem was that I had HUGE amounts of glue in some places, and none in others. Not hard to see why some have had problems with the Legends coming loose/vibrating. No big deal to fix though.

I am pretty lucky in the WAF as mine is totally understanding: as long as the sound is LOUD and CLEAN. Obviously the Legends fit the bill.

Now my DIY sonosub that's 30" diameter and almost 5' tall is another story. Of course once she hears the deep/clean bass she'll love it, especially on some of the Techno stuff she listens to. I listen to action movies at/near reference and she NEVER tells me to turn it down, and my 3 & 5 year old sons sleep right through it....HT nirvana

This message has been edited by Mlstrass on 04-15-2002 at 10:42 PM

[HornEd]

Mlstrass, I trust you will keep us posted on your DIY 30" Sonotube Sub (inc. photos?) during its construction. I have considered a four-driver 30" custom tower to go with my Heritage music system.

It has been said that people who build their own speakers are usually very happy about the results... even if everyone else is not impressed. From your above comments, it looks like we might need a Supplemental WAF Report on the finished project! -HornED

[Mlstrass]

Update:

Bucking magnets & x-over FINALLY arrived. Klipsch parts dept. charged my MC, but never shipped. Took a little while to straighten things out, but all is OK now.

Tonight I'll be installing the x-over and glueing the new baffle in place. Will also install the speakers and let it dry overnight. Still need to drill the holes for the grill mounts. Will get to demo it tomorrow night

DIY sonosub is totally kicking butt!! Wife and mother-in-law actually like the way it looks in the room, and the sound is incredible. My neighbor 2 houses away gets freaked out when it shakes her windows...seriously. EVERYONE who has heard it can't believe the amount of sound it puts out, I can give the low-rider/ricer "bass" cars a run for their money! Still have to make a test disk to get some SPL readings and need to take some pics.

Also need to sand/paint the amp box I built, but right now just enjoying everything. Take care...Mike

This message has been edited by Mlstrass on 05-07-2002 at 04:12 PM

[Underhanded Penguin]

MIstrass, you have a wife that listens to techno??? That is probably the coolest thing I've ever heard. Can you tell me whereabouts you found her? I would like to get one like that.

-UP

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