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My $50 Cornwall Project


RobC63

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25 minutes ago, moray james said:

Thanks, guess I should have read the first post and not just looked at the picture and the responses, they should turn out to be a nice set of verticals. carry on.

How many times have i thought or or writen something along those lines as well... ^^ You´re welcome.

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STEP 2: FABRICATING THE (REMOVEABLE) GRILLES

 

Materials Needed:

 - (2) 36" X 30" X 5/16" Masonite Boards (dry erase board) / $4.88 ea.

 - 16 oz. can Guerilla Glue All- Purpose Spray Adhesive / $5.99

 - 2 yards of Speaker Grille fabric (Ivory) / $22.99

 - 20 feet X 1/4" square wood dowel @ $0.29 per foot / $5.80

 - 12 oz. Guerilla Glue Clear / $2.99 

 - 4 oz. container White Craft Paint / $0.99

 - 4 oz. container Ivory Craft Paint / $0.99

 - (2) 4" Klipsch OEM style Logo badges / $15.99 for both

 

Total Cost for this Step: $65.50 plus tax

 

Labor Time Needed:

 - Approx. 7 total hours to trace / cut grille pattern & fabric; glue fabric to board, secure w/ staples, cut / paint / attach 1/4" dowel trim and logos

 

 

Masonite Board, Guerilla Glue (both types) came from Home Depot

Grille Fabric was ordered from Amazon (they had about 20 colors to choose from) 

Dowels and Craft Paint came from Hobby Lobby

Logos were purchased off eBay

IMG_7528.JPG.f53f52f52bf456809f8b48417bfbb4df.JPG          IMG_7530.JPG.5191a8e7eda84a0ba430c6cae91155ec.JPG

 

 

Found a grille pattern right here on the Klipsch Forum for Vertical Cornwall speaker grilles. Transferred the measurements to the masonite board using a thin line marker.

Cut the openings using a drill to start each opening, and a jig saw to complete the cuts.

Wasn't too difficult; I read that you could use a router to get more professional looking results. Didn't have a router, LOL . I am satisfied with the hand cuts, since they will be covered with grille fabric anyway.

 

IMG_7527.JPG.021800ddbf6c22ff260438f1c65413c0.JPG

 

Cut the fabric so that there was a 2" - 3" overlap on every side. Cut the corners diagonally to avoid too much excess fabric in the corners. Spray a 1" wide swath of glue onto the edge of the masonite from end to end. Wait about 1 minute for glue to set tacky, then lift the fabric overlap onto the glue and press down the entire length. Glue holds pretty well after about another minute. After securing the first side, place something heavy on the freshly glued side. Go to the opposite side and lay down the glue. Be sure to gently (but firmly) pull and stretch the fabric before pressing down on the glue. The goal here is that the fabric should be taut over the entire grille front face; you don't want any sags, lines, creases or lumps. Sounds difficult, but actually was pretty easy (these are the first grilles I have ever made from scratch and I didn't have any issues getting it tight and uniform).

 

IMG_7531.JPG.7fe3894df37119ead838a059264e29c2.JPG

 

IMG_7534.JPG.54142d5b2c60492275a8ce3f84679768.JPG

 

Once all sides are glued down, secure the glued areas using a staplegun and 1/4" staples.

Then, take the scissor and cut off the excess overlap (whatever parts are not glued / stapled down).

 

 

IMG_7535.JPG.cddf02162af50cec279b9f9547921345.JPG

 

Your semi - finished grilles should now look like this from the front side:

 

IMG_7536.JPG.0ea8cdf7af582d32385a97b6cd82b5b6.JPG

 

Unfortunately, I forgot to take photos while doing the grille trim work. It wasn't difficult, and if you follow the directions below it should all make sense even w/o photos...

 

Next, measure and cut the 1/4" square dowel to fit as trim around all 4 edges of each grille. Mock it up (don't glue yet) to make sure there are no gaps or overly long trim pieces.

Then paint the dowel trim on 3 sides (the 4th side will be glued down to the grille) and let dry. In my case, I mixed a little of the Bright White and Ivory together to get a color that matched the fabric. 

Once the dowel trim pieces are completely dry, glue in place based on the mock up you did earlier. Allow the glue to thoroughly dry.

 

Last, attach the grille logos. Some will have adhesive backing, some will have to be screwed on (mine were screw on).

 

Here's a shot of the finished product. In hindsight, I got the "large" logo badges; probably would have looked a little more 'factory' with the smaller size (2" I believe).

And you are going to have to wait until the end to see them actually on the speakers, LOL

 

But again, not too difficult to make these - and I think they look decent for under 70 bucks and a days labor...

 

IMG_7876.thumb.JPG.ce849e47efaf338f97e990ec35d37521.JPG

 

 

 

Edited by RobC63
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STEP 3: BUILDING A PAIR OF RISERS

 

Materials Needed:

 - 14 linear feet of 3" X 1" oak plank (actual measurements 2.5" X 0.75") @ $0.59 per linear foot / $8.26

 - (16) #8 X 1.5" stainless steel wood screws / $4.88 (for 100 screws)*

 - Leftover Black semi-gloss paint (from painting the motorboards) / $0.00

 

Total Cost = $9.04*

 

Total Time Needed:

 - Approx. 3 hours to measure / cut wood sections; drill / screw together and then paint the risers

 

* Total Cost reflects $0.78 for the (16) screws needed to assemble the risers. The remaining screws will be used to secure the back panels to the speakers (the original screws were badly tarnished and some were missing).

 

Putting these risers together was very easy - I kept the design super simple to keep the costs down, and also because in my particular situation I don't plan on moving my speakers around very much. If easy movement is important to you, I would suggest adding caster wheels behind the risers for mobility - or even swapping the risers out altogether for some suitable sized casters.

 

Anyway, this really was pretty quick and easy -

 

Start by  measuring out the riser pieces. For Cornwalls, the speaker dimensions are 25" wide and 15 1/2" deep... you want the riser to be slightly smaller than that, so the the speaker overhangs the riser by about an inch on all sides (no functional reason for that, it just looks better - more like a short pedestal -  than if the riser was flush with the edges of the speaker all the way around)... so I went 23" for width and 13" for the depth:

 

IMG_7871.JPG.9f6713ee39e8c88daa498c3fe288b1d6.JPG

 

I used a jigsaw to cut the pieces (the piece with the "X" will be scrap)

 

IMG_7872.JPG.04aba1d92b6ea342806c0515153eb305.JPG

 

 

Next, drill (4) holes in each corner of the longer pieces, about 1/4" from the corner edges. Use a 1/8" diameter bit.

Once you have the long pieces drilled, mock up the shorter pieces perpendicular on the ends; then drill again into the same holes until you have drilled about 1/2" into the side pieces

 

IMG_7869.thumb.JPG.529474f6f018dd30aa9d5c081694a169.JPG

 

Then,  insert a screw into each hole and tighten until the side pieces are firmly secured.

Repeat on all 4 ends until the frame is completely put together and tight

IMG_7870.JPG.12dfc50c7fd37a4d5815328af21c65ee.JPG

 

IMG_7873.JPG.df75d06fffb2e214953f25220b7ce22f.JPG

 

Use the leftover paint to paint the riser outer panels and top and bottom edges. Don't worry about painting the interior of the riser, you will never see it.

I used the leftover paint so it would match the motorboard, but you could stain these to match the speaker veneer if you wanted to

 

IMG_7874.JPG.e0a9bc8755e20d12355e76f2a4f0b205.JPG

 

All done and ready to attach to the bottom of the speakers - but you are going to have to wait until the end of the Project to see how that looks...

IMG_7877.JPG.c58a6fabc3cc972ce83e7ad2012f3b69.JPG

 

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For anyone keeping score -

 

The running tab so far comes in @ $131.47 (plus tax); so just under $140 (and 15 hours of labor time) for all the cosmetic work so far. The only thing left cosmetically is to remove the white paint splatter from the rear panels (probably with a little 'Goo Gone') and maybe touch up the original brown painted surface a bit.

I think it's safe to say that the total tally for all cosmetic restoration will come in a bit under $150... so, right now, for $200 total (including the purchase price) I've got a very nice looking set of Cornwall cabinets, complete with new removable grilles and nice 2.5" risers..

Of course, the key is getting these back to where they sound like the classic vintage Cornwall. 

To that end, I have found 2 vintage K-33 woofers on eBay. One has arrived already (2 different sellers) and one is supposed to arrive today or tomorrow. I know that Bob Crites stocks OEM-spec drivers that I have heard are very good quality; in the end, however, I decided that I wanted the real (vintage) deal, if I could find decent, functional examples (and I did). Didn't really save very much money vs. buying new from Crites - but in this case it really wasn't about saving money.

I have placed an order from Bob for repair kits for the original Klipsch "B" crossovers, as well as some of those rubber gaskets for the midrange horns. 

In the mean time, I will start the cleaning / inspection work on the drivers I have and hopefully no unpleasant surprises along the way...

 

 

 

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One thing you might do on the risers is attach some corner triangle braces which helps their solidity a lot.  That's also a way to attach mitered corners without screws showing and is popular/common in furniture.  

 

Here's a link to Crites website showing his risers and how that's accomplished.  (no affiliation)

 

https://critesspeakers.com/heresy-slant-risers.html

 

Looks good!

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STEP 4: CLEANING THE REAR PANELS

 

Materials Needed:

 - leftover 400 grit sandpaper / $0.00

 - Howard's Restor-A-Finish 16 oz. container / $8.99

 

Total Cost:  $8.99 (plus Tax)

 

Total Time Needed: Approx. 2 hours to sand and refinish

 

Not really a full-fledged "step" in this resto, but I thought it might be good to document it anyway.

Task here was to remove the massive amount of white paint splatter that had somehow gotten on the rear panels at some point in time.

 

Tried "Goo Gone" and that was a bust. I'm guessing because the paint splatter had most likely been there for decades.

Ended up doing a light sand over the entire panels - minus the label areas. Used the 400 grit sandpaper leftover from the rest of the cabinet work:

 

IMG_7883.JPG.f422cec4aa72461d3a0005bbff9109ce.JPG

 

 

Next, a wipe down with a damp cloth to remove any residue

 

IMG_7884.JPG.6c22ff9dc43be0461eb8d62c55e4eaf7.JPG

 

Lastly, 2 coats of Howard's Restor-A-Finish applied with a clean dry cloth. The lighter tone finish was perfect here

 

IMG_7885.JPG.44bb3f3a5d8d380b3304ad5e5d079e91.JPG

 

Had to go over a couple of light colored spots a third time. Then let dry for bout 4 hours of until dry to the touch. 

Here's a couple of Before & After shots:

 

                                                                 BEFORE                                                                                                                                                           

SPlat.thumb.jpg.06526b9e1c0bba318802c9b32f68c0d0.jpg 

 

 

 

                                                                                              AFTER

IMG_7887.JPG.a60ec8730cac232a85c2cb6b741a7e81.JPG

 

 

Not perfect... but definitely a large improvement :)

 

 

 

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3 minutes ago, RobC63 said:

 

                                                                                                                                                                                                                                       

Not perfect... but definitely a large improvement :)

Looks great to me ,  these are turning out to a great looking pair of Cornwalls ---

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While waiting for my crossover parts to come from Bob Crites, I figured it's a good time to clean up all the drivers.

 

As I said earlier, I found (2) K-33 Woofers to replace the subs that had been installed sometime in the past. Interesting to see the differences between the OEM woofers and the aftermarket subs:

 

IMG_E7891.JPG.fae0f4b25039b5c224152ffa31e7e9e8.JPG 

 

IMG_7892.JPG.66e61a6d997ac9180b6956b18f468b0a.JPG

 

Pretty obvious that the originals are substantially better built; and with significantly larger magnets. Should be an interesting upgrade to the sound profile.

 

Got all the internals cleaned up and ready; now we just wait for those crossover parts...

 

IMG_E7899.JPG.8e2759b11454b358311a8b442a3acd0d.JPG

 

 

 

 

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9 minutes ago, RobC63 said:

While waiting for my crossover parts to come from Bob Crites, I figured it's a good time to clean up all the drivers.

 

As I said earlier, I found (2) K-33 Woofers to replace the subs that had been installed sometime in the past. Interesting to see the differences between the OEM woofers and the aftermarket subs:

 

 

 

IMG_E7899.JPG.8e2759b11454b358311a8b442a3acd0d.JPG

 

 

 

 

Rob  , What brand are these tweeters ------do you have a close up picture   ?   -

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STEP 5: REBUILDING THE CROSSOVERS

 

Materials Needed:

 - Crossover Rebuild Kit, Type "B" Klipsch / $57.00 (plus $9 shipping)'

 

Total Cost:  = $66.00

 

 Time Needed:

 - Approx. 1 hr. to remove and replace crossover capacitors.

 

With all the cosmetic work now completed, and a pair of OEM Klipsch K-33 woofers secured and the other drivers all cleaned up... time to get to work on restoring the sonic capabilities of these Cornwalls back to their intended specifications.

 

The last remaining piece would be the original Klipsch crossover networks. To that end, Bob Crites sells crossover rebuilding kits specifically designed for the Klipsch Cornwall speaker (as well as kits for pretty much every other Klipsch speaker ever made). It's very easy to figure out which kit you need; Klipsch has the crossover 'type' right on the label.

 

My Rebuild kit came with 4 capacitors / 4 capacitor holders / 4 cable ties; and a schematic drawing that shows the wiring of the new caps. Though it's really easy if you simply remove 1 old cap at a time, and replace with the equivalent value modern cap. Each Rebuild kit has all the parts for a pair of speakers.

 

Again, this is a very easy thing to do, provided you have the right tools and a soldering iron. You don't need to be an electronics expert to recap a crossover - at least not these large and simple Klipsch crossovers.

 

Here's what the original crossovers looked like, right out of the speaker cabinets:

 

IMG_7935.JPG.33ac00e0bbbb02fe028afc4c8cf4f708.JPG

 

Cut the leads to the first cap. Be sure to mark which lead goes to which cap terminal.

 

IMG_7936.JPG.91ae8fd35f4f348e95ba1e93daebb97b.JPG

 

Unscrew the cap from the base

 

IMG_7937.JPG.30100287a130a7251478bf35e4b33e3b.JPG

 

Use a wire stripper to strip the leads

 

IMG_7940.JPG.3cf82b39f6e9393b82e1d7096f5aa590.JPG

 

Attach the new cap holder using an existing screw and hole

 

IMG_7943.JPG.c772695d0359a534c1e5efcc4f12ec51.JPG

 

 

Examine the old cap to find the correct replacement

 

IMG_7938.thumb.JPG.a60a2ed9a5b45ece387ba75ba567fa6f.JPG

 

Choose the correct replacement from the rebuild kit

 

IMG_7942.JPG.7aeb376164a0e4789f2815325785c9e6.JPG

 

Secure the replacement cap to the board

 

IMG_7933.JPG.f379d06546dff85bb313ff1c93b6a015.JPG

 

Solder the lead wire to the capacitor lead. Clip off the excess lead on the cap. Repeat to solder the second lead to the other end of the cap.

Repeat the process for the second capacitor replacement.

Then repeat the entire operation for the second crossover board.

 

End result below:

IMG_7934.JPG.f91f61cd8049611cc1fcf0a4042d376a.JPG

 

 

I'm going to keep the original caps stored away in case I ever decide to sell these speakers (in case the next owner is a fanatic about 'original parts')

 

 

 

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1 hour ago, avguytx said:

 

I thought the same thing.  Definitely not the size of K-77's or any iteration I've seen either.

 

What I was told from the original owner was that those tweets were a special order on the original build back in 1971. The caps were added apparently when the son replaced the original woofers with those car subs, as the owner said they were not installed originally - just the standard "B" crossover.. And, for whatever reason, the kid actually bypassed the Klipsch crossovers (and the midranges) and direct wired the subs and the tweeters straight from the speaker terminal. So these were running like a 2 - way instead of a 3 -way when I bought them.

I only found this out after I got them home and hooked them up and realized the mid horns were silent. I opened one of the cabinets and saw the 'hack job' wiring that had been put in place. I called the seller back to ask a few questions but since the seller had given them to his son sometime in the 1990s he was a little short on details as to what had actually been done to them. He guessed that maybe the crossovers went bad and that's why the son bypassed them. No explanation as to why the mids had been bypassed - especially since they worked fine when I tested them... maybe the kid was a 'basshead' or something?

 

Normally I would have demo'ed the speaker first before buying; but these were in a storage unit for (I was told) maybe a decade... and, for $50 I wasn't about to "demand" that I be able to test them before I bought them, LOL

Edited by RobC63
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27 minutes ago, RobC63 said:

 

What I was told from the original owner was that those tweets were a special order on the original build back in 1971.

--ROB  ------These tweeters are not bad at all ,  these are Atlas Alnico HR-3 ,as per your reply  - metal horn, very good sounding from what is said  on the web and they extend higher if not just as high than the K77 -  the difference is  they are 16 ohms ,  which means they draw 2x less power , you can't overload them  which is a weakness of the k77 and it could the reason for swapping these , since the earlier k77 from Klipsch was also a 16 ohms tweeter ----just plug them in the right way , test them , they sound good to you , call it a day -

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