Vol'ti - v. - to turn over a new leaf; to move forward

2010 note: please keep in mind as you're reading through this photo-essay, that it was written in 2007, before I was in business and before I discovered the larger midrange horn format for Khorns.  A lot has happened between then and now!

"M" Khorns
A Restoration By Greg Roberts
July 2007

These poor Khorns need help!

These are in good solid condition overall.  I've noticed some water marking on the bottoms, meaning that they have seen a little bit of moisture somewhere along the way, but upon close inspection, the plywood has not delaminated at all, and everything seems o.k. to me.  The structure of the upper and lower cabinets is sound.  These are perfect candidates for a re-veneer job.

Everything works.  They have the preferred vintage round-magnet tweeters and the K-55V midrange.  They came with K-33V woofers, which I've never seen before.  I don't think these are original.   They look like K-43's in their construction, more of an industrial woofer with higher power capacity.  I am going to purchase new K-33 replacements.

They have the older style AA crossover networks which work fine but could probably benefit from an upgrade, which we'll talk about later.

The model as shown on the stickers is K-C-FR.  The "K" means Klipschorn, the "C" is the style of the cabinet (more on that later), and the "FR" means Fir Raw, which means they were made with Fir plywood with the top veneer layer being Fir and they were delivered to the customer without any finish on them.

The serial numbers are 5M680 and 5M681, consecutive.   The "M" in the serial numbers indicates that they were built in 1974.

When Klipsch delivered "Raw" speakers, they didn't finish the backs either.   When Klipsch finished speakers, they would paint the backs black, which really looked nice.  This is going to be done as part of this restoration.

The grill frames are in great shape, as is the grill cloth, although I think black grills will look the best with Santos Rosewood, so they will be changed to black

Here's some more pictures of these speakers in the "before" mode, including detailed shots of the bad spots.  Please do not be alarmed by the pictures of the chipped veneer and bad corners, this is all easily repairable with high quality fillers.   One of the most important jobs I do when restoring these speakers is to make sure the cabinets are completely sound before installing the veneer.  I spend hours carefully removing chips and any loose wood and filling those voids back in to make sure that the cabinets are as sound as possible before putting the veneer on.

What To Do

So, here's what I'll be doing to restore these speakers.

  • Completely break down the speakers, take out all components and dismantle the various parts to prepare for the restoration.

  • Check all structural elements of the individual cabinet pieces and repair where necessary.

  • Check the tweeters and midrange drivers for proper operation and physical condition.

  • Thoroughly clean and detail those components.

  • Purchase two new replacement K33 woofers.

  • Replace any stripped screws.

  • Paint the midrange horns if necessary.

  • Sand all wood parts in preparation for new veneer.  This includes checking for voids and filling, removing any loose veneer and filling, and basically prepping the wood parts so that all edges are re-squared and solid and ready for the new veneer.

  • Make risers and new plywood pieces to turn these into "B" style cabinets (more on this below).

  • Fix any hardware issues, like the connections of the top horn cabinets to the bass bins, or replace any missing feet on the bottoms of the bass bins, and replace the missing logo.

  • Install new veneer, sand, detail.

  • Install trim boards of solid Rosewood on the front bottoms of the bass bins, as Klipsch did on their finished "B" cabinets.

  • Detail the backs of the speakers and install a primer and satin black paint to the backs of the bass bins and the insides of the upper horn cabinets.

  • Apply several coats of Minwax Wipe-on Polyurethane.

  • Install black grills.

  • Re-install the tweeters, midrange horns and drivers, and the woofers.

  • Clean all connection points and install new wiring for all drivers.

  • Install new "A-type" crossovers built by Bob Crites.

  • Do a final Fit and Finish of the assembled speakers.

  • Test the speakers to make sure they are functioning correctly.

"C" Style to "B" Style

The speakers right now are the "C" style cabinets, which means the top horn cabinet sits directly on the bass bins. Here's a picture:

The "B" style cabinet has an extra riser, which lifts the top horn cabinet up off the bass bin by about one inch.

Here's a picture of the "B" style, which is what I plan to change these to.

See how the top horn section is lifted up with an extra spacer?

The first job is to disassemble the speakers.  The top horn sections unbolt and unscrew apart fairly easily.

Here are the bass bins by themselves.

I have plenty of storage for parts.

The filler I use is Minwax Hi-Performance Wood Filler.   It's kind of like Bondo, but made specifically for wood restoration.

The repairs made with this filler are stronger than the wood, and they do not chip off like the wood edges.

Here I've made the new parts for the "B" style risers.

It takes several rounds with the filler to get everthing perfect.

Bass bins sanded and getting the first layer of filler.

The veneer is paper-backed, Santos Rosewood from Oakwood Veneer

I really think this 10mil paper backed veneer is going to work a lot better than the raw wood veneer I've been working with.  I'll have to be careful about not getting glue on the face of the veneer because I can't do as much cleaning and sanding as I've been doing.  The veneer is already sanded very smooth, and if I keep it clean, all I'll have to do is a finish sanding with very fine sandpaper.

I've still got some filling to do on the bass bins to prep for veneer, but I'm going to start the veneer very soon, probably Monday.  Right now I'm figuring on an April 6th finish date.

Here's a couple of photos of the veneer.  Imagine this on the front of the bass bin!

Like liquid rosewood poured over the cabinets!

There are multiple coats of wood filler and I've done lots of sanding on the bass bins.   I'm spending a lot of time working on the backs of the bass bins that will only be seen by the new owner before they are installed in the corners!  But I think it's going to be worth it.

Even the bottoms are being filled, sanded, and painted.

I found a couple of major voids in the plywood.  I always check all the panels to find things like this.  Once I start to uncover a void, I follow it until it ends and then fill it.  This large void has been there since the speakers were new.  I wonder what affect that had on sound quality?  It was right in front of the woofer.   It's better now, and that's my overall goal, to make these better than new.

The stickers are carefully taped off so the black paint will go right up to them.

I've finally got the bass bins all filled, sanded, and primed.  It was a lot of work doing this, and probably not worth the amount of time I put in.   But the backs of these speakers will look very nice indeed.

I think I will put a coat of black paint on before I veneer them, and then a final coat after they are veneered.

I've also removed all of the old cloth from the grill frames.  There were at least 41,000 staples holding that cloth on!

The paint is all on the bass bins now.

I've started working on the grills too.

The first piece of veneer being glued up and ironed on.

Looking good!  This is the piece that I'll rip up to make the riser pieces out of.

I found a nice tool for working with the grill cloth to stretch it.

Here's the first one done.

Glueing up two panels.

I tape down the veneer so the glue doesn't get on the fronts.

The roller is a must to keep the amount of glue even and it results in a flatter panel.

This new glue that I'm using seems to be working really well.  It's available from www.joewoodworker.com

I've ripped down the small panel that I veneered last night into 1" strips for the risers, and I'm glueing them together in a picture frame clamp to make the risers.

2 panels all veneered, trimmed and ready for edgebanding.

Large batch ready for glue

Bass bin front veneer pieces.

I made the front pieces of veneer for the bass bins a little wider than needed and cut the sides off to use as the edge band.  This way the grain lines will be very simlar going from the front over the edge.   I've glued the edges and ironed on the edge band in this picture.

The edgeband overlaps all sides, but I actually kept it very close on the bottom edge because it's hard to get in there to trim it back.

Tricky.  Very carefully.

Another very careful step.

A sanding block made with a 120 grit belt makes a great tool.  I only push the sanding block one way, not back and forth or it will chip the veneer.

I use this handy trimmer on the edges that go with the grain.

Using the sanding block for the underneath edge.

After using the sanding block on the top edge to clean it up, I put a small bit of glue down the edge with my finger.

Here you can see the beautiful front bass bin pieces.  Man these are going to look killer!  When I trim long end cuts, I don't take any chances on the straight edge slipping and having the knife cut into the veneer, so I clamp the straight edge in place.

Right now I have about 45 hours of work into these, not including the work on the grills.

I currently have all the panels veneered and all I have left to do with the veneer is edgebanding.  Oh, and the Klipsch Heresy speakers that I have enough veneer left over for!  Anyone for matching rosewood Heresy rear surrounds?

Tomorrow I'm going to assemble and disassemble the tops and work on edgebanding.

Here I'm starting the assembly.  The birch colored ones are for a customer who had the "D" style Khorns with no finished top and no grills.   I figured I might as well assemble them all at one time.

Only one word will do.  WOW.

Here's a couple teaser photos.

A little miscellaneous information.  Someone asked for this info on the materials I've been using.  It took two 4 x 8 sheets of veneer to do the Khorns.  I got the veneer from Oakwood Veneer.   Cost was about $350.  It took a gallon of glue for the veneer on this project, which was about $50 with shipping.  I've gone through about 20 spray cans of primer and paint at a cost of about $5 each, and I've got a lot more to do.  20 or so razor knife blades, lots of sanding discs, about one container of Minwax hi-performance wood filler, a couple of band-aids, about $100 for promotion so far on ebay and Audiogon, I bought a nice Santos Rosewood board to make the trim boards out of, which was about $100, tape, screws, lightweight plastic.  I guess that's all I can think of right now.

I was lucky and made contact with someone who wanted to trade my woofers that were in the Khorns originally, one of them blown, for a pair of beautiful original K-33's.  I'll get a picture of them before I install them in the bass bins.

I made some real good progress.

All of the veneer is now installed, including all the edgebanding, and the initial sanding of the veneer is done on all ten of the top horn pieces.   They are all masked off and ready for paint.  The painting process takes some time because of the waiting involved between coats, so I'll be doing the grill work that I have to do while the painting is being done.

Putting the veneer on before painting, means that the edges of the veneer will be painted too.

It takes about 20 minutes to mask off each of the six large top horn pieces.

The bass bins are in the paint room getting a touch up of black paint.   Once that's done, they'll get a final sanding of the veneer and I'll install the woofers.  I purchased really nice wire for the internal wiring of the Khorns.  I'm also using nice banana binding posts for the woofer connections.

All the pieces are painted now.

Next, I'll do the final sanding on all the veneer.

Other materials or items that I used for this project, continuing from the list from before (someone asked):   Cleanwoode, which is a mixture of solvents, I bought new filters for my respirator today for $30, sanding sponges, blue tape, polyurethane glue, dust masks, cleaning rags.  That's all I can think of right now.

I've been working on a pair of Heresy's for the last couple of days and I've got them in the paint room right now.  Tomorrow I'll be starting the finish sanding on the Khorn pieces.  Wish me luck, there's always the risk of sanding through the veneer.  UGGGGGGHHHH!

Here's a couple of pictures of the Heresy's.  I had just enough veneer left over from the Khorns to do three sides of each of these.  I don't usually do Heresy restorations because they don't sell for enough money to cover the hours that it takes to do the work.  But I decided to do these ones because I had the veneer and this particular pair came to me in pretty rough shape, just calling to me for help!

The Heresy's have all the veneer on now and they're getting painted tomorrow, so they'll be caught right up with the Khorns.

It's getting exciting, I'll be putting finish on the Khorns and Heresy's next week!

The sanding is done, I've cleaned the shop thoroughly, and I've got all the speakers and parts set up and ready for finish.  Sorry there's no new pictures, I didn't see the sense since they don't look any different.   I'll take pictures after the first coat of finish goes on.

I'm going to put urethane on all the various pieces of the Mkhorns, the rosewood Heresy's, a pair of Walnut Heresy's that I refinished recently, and another pair of rosewood Khorns (Tkhorns) that I restored about two years ago, all at the same time.

I originally put an oil finish on the Tkhorns but I didn't like the way the finish came out, so I've been letting them dry in my dry house for the last two years and it's now safe to put a urethane over them.  The Tkhorns have also been sold to a gentleman in Boise, Idaho.

All of these speakers and parts will get various levels of cleaning and prep for the urethane and I should be able to get the first coat on tomorrow.   For the next 4 days, my shop will be very "still", to keep the dust down while doing this finish work.   I'll sand with 400 grit between coats and put a coat of urethane on once each day.

The pictures today aren't very good because of the lighting, but I think you'll get the idea.  The grain really POPS now with the finish.   There's just nothing like Rosewood, it's formal, rich, tasteful, interesting, and just plain beautiful.

Update 5/1/07
Rain the last few days and the finish wasn't drying good.  But today things dried right out and I got the second coat on.  I use 400 grit sandpaper to lightly sand between coats, then use my hands to rub and clean the wood before the next coat.  They really are hand-rubbed.

The "T" Khorns made it into the shop today and got their first coat.   These are Khorns that I re-veneered a while ago, in raw wood veneer.

These really have some beautiful veneer.  This is raw wood Brazilian rosewood, and I did have issues with bubbling veneer when I installed it.   The glue and the raw wood veneer just didn't work well together.  The paper-backed veneer with the Heatlock glue that I'm using here on the "M" Khorns really does work a lot better.

Glare from the lights, but notice the wonderful grain pattern.

I think the finish is done now.  I'm going to make a close inspection this weekend and if they need one more coat I'll wrap it up this weekend.  Next is the assembly of parts.  We're waiting for the new mid horns, new tweeters, and new crossovers to be delivered, which could take a few weeks.

5/5/07 update
I did put one more coat of finish on everything and it's taking quite a bit of time to dry.  I've started making cane grills for the Tkhorns and I'm telling ya, it's a smash hit, the contrast between the light colored cane and the dark rosewood.  Wait till you see it!  I can't take my eyes off them.

5/13/07 update
I did the cabinet assembly yesterday.  New felts on top of the bass bins.

There are three different options on these for the front bottom trim.   Klipsch originally had a straight piece of solid hardwood trim at the bottom of the bass bins, about 1/2" thick and 2-1/4" tall.  I've done something a little different, but it will be up to the new owner as to which he would prefer.

Option #1 is with no trim.

Option #2 is with two trim pieces like this.  These are solid rosewood trim pieces, ripped at a slight angle to represent the horn-loading of the speakers.  The edges have a very slight bevel applied that create a tiny "V" where they butt together.

Option #3 is with the two trim pieces like this.

Which do you prefer?  Please email below and let me know.

I'm testing and installing drivers next.

I've been cleaning and assembling parts.

Here's a few pictures of what the woofers look like.  This was a lucky find, a great old pair of K33's.  Thanks "speakerfritz".

I installed screen on the backs of the bass bins.

Installed a small wood trim piece to cover the staples.

Gold plated connectors all around, and new 12ga twisted-pair wiring.

The Trachorns showed up the other day, but I haven't unpacked them yet.   I'm installing all the original components and I'll test the speakers that way first before I get into installing any upgrades.

5/21/07 update
Finally got everything assembled today and got the speakers up and running.

I found some great material to seal the backs of the bass bins into the corner walls.  This is a garage door weatherstrip made of very soft rubber.

I made new brackets to hold the midrange horns.

I'm using a pair of Bob Crites "A" crossovers for testing.

Internal woofer wiring is soldered.  External wiring is 12 guage twisted pair and gold plated connectors.

The front bottom trim is permanently attached now.

Not quite in the corner tightly, but they fill my 24 x 32 room very nicely just the same.  I got about 60 or 70 watts into them with the HK930.

I got the Trachorns unpacked today.  These are from ALK Engineering, and they are very nicely made.  The workmanship is first rate.  My only critique would be that I think there should be more staples holding the grill cloth on.

I just got word that the ES networks will be shipped next week.  Still waiting on the Beyma tweeters from Italy.

With the new owners permission, I'm going to be able to move the Khorns to my house for testing with the various components.  Thanks Sergei for letting me do this.   What a great opportunity to try out the ES networks, the Trachorns, and Beyma tweeters, all in various configurations with different power amps.  I'll have to set aside most of a day for all of this and send the wife out shopping.

Here's a photo of the crossovers in my living room just waiting for the Khorns to arrive.  The Khorn in the background is a 2/3rds scale mini Khorn, built just like a real Khorn but with a 12" woofer, a smaller midrange horn, and "B" crossovers out of Cornwalls.  They really sound nice, but they need a little more power than my SET amps put out, and they are not imaging well in my 22' long living room.

The Beyma tweeters finally showed up.  I was surprised by how big and heavy they are.  They seem nicely made.

Bob Crites was nice enough to send me a pair of his CT-125 replacement tweeters for the Klipsch K-77 to try out during my testing.   These are highly regarded by the Klipsch Forum members who have purchased them.  It will be interesting to compare to the Beyma's.

I also decided to get a pair of Bob Crites cast-frame woofers that are made to replace the K-33's.

Update 6/23/07
Finally, I got to do some testing today.  My brother-in-law helped me move the Khorns to my home, and it took most of the day to move things and get everything set up.  I gave my wife some money and arranged to have the house to myself all day and early evening.

Here's a picture of the living room full of speaker parts and furniture moved all around to give me an unobstructed audition of the speakers.

First of all, I have to say that these speakers look spectacular in my living room.   It's different having them in a home environment than it is to have them at my shop.  I've had Khorns in this room for over 15 years, so I've gotten used to seeing them in the corners, but none have looked as beautiful as these.   I'm referring to the wood grain of the veneer more so than the workmanship.   Sorry for the horrible pictures, but the lighting in my living room is not good for photography.

I squeezed a few more components in with the regulars to do the testing.   I'll be using the same source for all my testing.  It's a combination of a Denon 1650AR used as a transport (which weighs about 20 lbs.), a MSB Link DAC III with Full Nelson upgrade, HDCD card, 24 bit/96khz upsampling, a separate P-1000 power supply, and a Monarchy anti-jitter box.  I'll be using a Creek Audio OBH-10 passive remote controlled attenuated volume control for all testing.

I decided to do the bass listening tests first and change out the K-33 woofers for the new Bob Crites replacements.  I wanted more power for this, so I used a McIntosh MC2100.  I was going to use a McIntosh C28 preamp too, but decided against it, so there is no preamp with this system.  Signal goes from the CD player to the remote volume to the amplifier.  I set the volume pots on the amplifier so that the remote volume control would be at full.  This way I would be comparing the same volume level for all songs and for both woofers.   I played 4 different songs, switched the woofers over in about an hour, and listened to the same 4 songs again.

First was "Sail On Sailer" off of the CD Pete Levin "Deacon Blues" 2007.   This is a great sounding CD with lot's of Hammond B3.  The particular song I chose has a nice combination of 5-string bass guitar, a strong kick drum, and the low percussion of the B3.
Next was a very nicely recorded jazz piece called "When A Woman Loves A Man" by Bennie Wallace - Moodsville.  This is on a Sony Demonstration disc SACD.   This piece has very nice low tenor saxophone sound that you feel as well as stand-up bass with a big fat sound.
Next was "Your Good Thing" recorded by Boz Scaggs on his "Come On Home" CD from 1997.  I'm not a Boz Scaggs fan, but this CD blows me away every time I listen to it.  This particular track is a good test of how well a speaker is balanced between beaming vocals and the really well recorded bass and kick drum.
Lastly was "Summer Fling" by Spyro Gyra from "The Deep End" CD 2004.   This track has great low bass and kick drum.  Spyro Gyra is a large group, so there's always a lot going on when you listen to their music, and it's a challenge for any system to reproduce it.  Very well recorded stuff.

Right away I noticed an improvement in bass response as compared to my last Khorns I had in this room.  Perhaps sealing the backs of the bass bins against the walls does help.

I did not notice much of a difference between the old K-33's and the new Bob Crites replacement woofers in the amount of bass or the extension of low frequencies.  But there was one noticeable difference, and that is with the upper bass and mid-bass frequencies.  The Crites woofers blended better with the mid horns.  Instruments like horns, organ, and guitar playing in the lower registers all sounded warmer.  I particularly noticed the difference with the saxophone in the Bennie Wallace piece.  Nice sounding woofers, but don't expect big improvements by changing woofers unless yours are damaged to begin with.

Update 6/24/07
I just spent the last four hours comparing new "A" crossovers with the ALK ES Networks.

I used two different amplifiers for this test.  I started with my custom JFL Horus 2A3 Single Ended Triode Tube Monoblocs.  These put out about 2 watts per channel and they have the best midrange sound I've ever heard.   No preamplifier.  The Khorns had the stock K55/K400midrange and K77 tweeters, the new Crites woofers, and new Crites "A" replacement crossovers.  Now, my SET's don't have the best bass output, so I kept my music selections pretty light weight.   I started with a Chesky production of Beethoven Symphony No.9 recorded in 1961, remastered in 1992.   I listed to the third movement, about 12 minutes long.  I then played a couple of Jimmy Ponder tunes, "Since I Fell For You" and "Sunshine" from "Something To Ponder", 1996.  These have terrific electric jazz guitar sounds.  Lastly I chose "Blue Rondo A La Turk" and "Take Five" from Dave Brubeck Quartet "Time out".  This recording is and older recording, so it's another good test to see which crossovers gave the most pleasant sound.

After listening to those tunes, I then switched over to my rebuilt Scott 299 A integrated amplifier.  This is a great sounding unit that puts out about 17 watts per channel.  I tweaked the bass up +1 and left everything else flat.  Music choices became more demanding.  I played "Gaslighting Abbie" from Steely Dan's "Two Against Nature", a song I'm very familiar with.   It has a very tight and pronounced kick drum sound, deep bass, and intricate layering of instruments and vocals.  Then I put on "Back In The High Life Again" by Steve Winwood.  This disc is a Mobile Fidelity Sound Labs disc that is really well recorded.  This particular song has a great mix of synthesizer sounds, and it is a very crisp recording.  I ended with a tune called "Stolen Car" off the "Sacred Love" CD by Sting.  This CD has loads of great bass, and this particular tune has a huge synthesized bass and kick drum.   The bass is over the top and a real good test.

So I listened to these six tunes on the two different systems with the "A" crossovers and then switched the crossovers out for the ALK ES networks.  It only took me about 10 minutes to switch the crossovers.  After the switch, I kept the Scott hooked up and played the last song first.  I was very excited because I had heard so much about the ALK networks and here I was finally getting a chance to hear them.  So on comes the Sting tune and immediately I can tell that the sound is different.  The midrange is softer, maybe smoother, but I can't really tell for sure.  Then I'm thinking that the bass is more laid back too, not as punchy.  The highs seem very smooth and nice sounding.  So is this an improvement?  It wasn't readily apparent to me.  I listened to the Winwood tune and really felt as though the bass wasn't punching through as much, and I also felt as though the lack of midrange was taking away from the impact and dynamics of the music.

So after about 10 minutes, I switched the crossovers back to the "A" replacements and listened to the same songs again with the Scott amp.  Immediately the music seemed to have more impact, more punch, but at the same time it had a harshness to it.

So I switched back to the ALK ES networks, still with the Scott amp and this time I stuck with the Winwood song to try to figure out what it was that I was hearing different.  It was then that I realized that the bass was actually extending deeper.  I don't know how this can be, but the ALK's definately extend the bass deeper than with the A's, but it seemed softer and less punchy, so again, I don't know if this is an improvement.  The midrange is also less harsh with the ALK's, sort of like they equalize out the upper midrange a bit.   The "voicing" of the speaker was now lower, deeper, and more laid back.   But is this having something to do with my perception of less dynamic sound?  Maybe it's just that the midrange horn output is lower and that is what seems to be smoothing out the midrange.  I'm still left with the question of whether this is an improvement.

Next, I switched over to the SET amps and listened to Beethoven's Symphony No.9 again.  Now this sounded better to me.  Just a tad more bass than the A's and the sound really did seem a lot smoother.  I then put the Ponder and Brubeck tunes on again and noticed the same improvements to midrange smoothness and extended bass.   So at this point I'm thinking we have an improvement, but I'm also wondering what the ALK Universal networks sound like.

Next up were the Bob Crites replacement tweeters with the ALK ES networks.   The tweeters went in very easily using the same holes as the K-77's.  The magnet just barely fit under the top, scraping against the top as I pushed the front grill back into the Khorn top.  I was not able to detect much difference between these replacements and the K-77's.  That is to say, both sounded very good to my ears.  Now, my ears are older and it's possible that I don't hear very high frequencies as well as some others.

The last thing I changed today was the midrange horns to the ALK Trachorns, and the tweeters to the Beyma CP25's.  The switchover went fairly well and only took me about an hour.  I had to very carefully push the wood horn back into the Khorn top, as it just barely fit under the top brace.   I had to move one of the braces that holds the top of the speaker at the back so the midrange horn could fit in.

I think at this point I was getting tired.  After playing with the midrange and tweeter output on the ES networks, I really didn't notice a lot of difference in sound quality.  I'm going to do some more listening and tweaking through the week before I give my final thoughts on the sound of these upgrades.

By the way, every combination of music, amplifiers, and speaker components that I listened to today sounded terrific.  The Khorn is an amazing speaker that is capable of reproducing sound in a very dynamic and moving way, whether with stock components or with these different components.  I believe Paul Klipsch knew exactly what he was doing when he chose the components and crossovers for the Khorn.  He had decades of time to work on tweaking the Khorn, and he changed very little over that time span.  As I said before, maybe it's just that I'm fatigued, but if someone were to ask me to summarize my experience today, I would say that in the end, after all the upgrades were installed, the sound was just different, not necessarily better than the stock Khorn that I started with this morning.  If better, not by much.

As I think about what I heard with the ES networks, I'm left wondering if simply putting a resistor in line with the midrange driver to lower the output, or tweaking the transformer taps to lower the output might not have the same affect.  I do think the low bass extended deeper with the ES networks, but I also think the sound lost some punch and dynamics.  The Trachorns just seemed like they were putting out less sound too.   After I tweaked the crossovers to turn the horn back up, it pretty much sounded just like the K400, which means it's really the same stock K55 driver that I'm hearing.   The Beyma tweeters did sound nice to me.

I'm very tempted to do another listening session with all the upgrades and then change everything back to stock and listen again.

Update 7/7/07
Over the last couple of weeks I've been able to listen to the Khorns about ten times with all the upgrades installed.  Just before writing this, I read through my notes above, and I don't know that I have much to add.  The Khorns certainly sound wonderful.  Every time I sit down to listen, I'm impressed with how solid the bass is and how loud and clear they play.   They have such a lively, dynamic sound that really brings all the detail and impact of the music right in your face.

But this description is consistent with how I would describe stock Khorns too.   I'm still not convinced that all these upgrades are actually making much of an improvement in the sound quality.  I'm noticing differences that could be interpreted to be improvements for sure.  

There is a difference between speakers that sound nice and speakers that are accurately reproducing the input.   I've had people listen to my Khorns and other Klipsch speakers and not like the sound of them.  One person in particular who I've known for quite a few years, prefers his Vandersteen speakers to my Khorns.  If you've ever heard Vandersteen speakers, you know that they are a great sounding speaker, and very different from horn-loaded speakers.  I would describe them as being "nice", "pleasant", and "soft" sounding.  I can fully understand why someone would prefer them over the sometimes "harsh", very "real", "dynamic", "live", "in-your-face" horn-loaded Klipsch speakers.

I think these upgrades that are installed in the Khorns, especially the ES networks, are actually changing the voicing of the speaker a little towards "nice", "pleasant", and "soft", and a little away from "harsh", "dynamic", and "in-your-face".  Is that bad or good?  Only the listener can be the judge.  In my opinion, some of the dynamic impact goes away as the character of the Khorn is changed to be "softer" and "nicer" sounding.

I've been asked if there are any of these upgrades that I would consider a "must have" for anyone who owns Khorns.  My answer has to be no.  It's going to depend on how much money you are willing to spend, and no matter what I or anyone else tells you about the upgrades, it's still going to be an experiment, because we all hear sound differently, and we all have our own idea of what sounds best.

But I will say this.  My experience with each of these upgrades has been positive, in that they all were very well engineered, very well built, and were easy to replace.  The people who are doing this very specialized work to provide us Klipschophiles with unique possibilities are to be commended.  Bob Crites is providing really good replacement crossovers and crossover cap kits at very reasonable prices.  He's providing us with a very good quality replacement tweeter, that to my ears sounds every bit as good as the K-77, and perhaps even a tad better.  The cast-frame replacement woofers that Bob sells are very nice, and after a couple weeks of listening to them, something is producing more bass output than I've ever heard from my Khorns.  It's either the crossovers or the woofers, or both.  I'm not one to believe in "break-in", but that may be my experience with these woofers, because they sound better now than when I first installed them.

The Trachorns are very well built wooden horns.  I've changed so many things over that it's hard to say for sure what impact these are having on the resulting sound quality when compared to the ES networks for instance.  My only complaint with these is that I think the grill cloth should be put on a bit straighter and with a few more staples.

The Beyma tweeters sound great.  Lush is the word that comes to mind.

I have mixed feelings about the ES networks.  First, they are incredibly well built and the sheer number of components is impressive.  If there's ever any question about why they cost so much, that will be put to rest when you unpack these things and arrange them on your kitchen table.  They should cost more than they do.  So there's no doubt that you're getting your money's worth in engineering, parts, and labor, but what about improved sound quality?   Again, this is a subjective thing, and to my ears, the sound was just different, not necessarily better.  I really liked how you could change the tweeter and midrange horn outputs.  I settled on the next to the highest setting for the tweeter, and the 2-5 setting on the midrange.   I certainly noticed a correlation between how loud I had the midrange set and how much dynamic impact I was getting from the speaker, which leads me to wonder if simply finding a way to adjust the midrange output on the stock Khorn wouldn't also provide similar results but at a far lower cost.  One last thought on the ES networks, with louder volume levels or less-than-high-quality recordings, the "softer", "more pleasant" sound was appreciated.  I believe the same could be said about Vandersteen or similar nice soft sounding speakers.

I have to say that there's something that I like about the simplicity of the "A" crossovers and how they just let the music through, unfettered, open, dynamic, and yes, sometimes harsh.

I'm sorry for being so long-winded, or for any contridictions that there may be in my analysis of all this stuff.  This was a lot to take in, and I've tried to give you my impressions of these upgrades as honestly and objectively as possible.

I am currently without any of my own Khorns, having sold the two pair that are shown here in these webpages.  I have another pair ready to restore for myself.

So will I include any of these upgrades in my next pair of Khorns?

I think I'm convinced that the woofers are a nice upgrade, especially since K-33's can be sold on ebay for good money, making the net cost output for the new woofers fairly low.  I loved the Beyma tweeters and I will probably try to incorporate those into the next set of Khorns.  But as far as the crossovers and midranges, I don't know right now.  I think I'll start with a pair of ALK Universal networks and see how those sound.  If I ever want to sell them, I can do so and not lose much money.  The Universal's allow for adjusting the midrange output, which is something I'd want to experiment with.  I've never tried damping the metal horns, nor have I tried the plastic replacement horns that Klipsch sells, but I think I will on this next set of Khorns.  Someday I'd like to experiment with a larger midrange horn and driver, like a 2" throat horn/driver combo and see how that sounds.   I think it would be nice to be able to adjust the horn and tweeter independently from the bass bins.  I also would like to build sides onto the next set of Khorns and enclose the bass bins as was done by Klipsch on the 60th anniversary Khorns.  I've got a few other ideas too, and when I do the project, I'll make a webpage for them.

Update 7/28/07
The speakers are back at the shop now.  I'm securing the crossovers in the tops, cleaning and installing the grills, and a final cleaning on everything before crating them up.

Crating materials

Update 8/20/07

Here's some photos of the crating process.

The crate weighed in at 835 pounds!

Here's the "Glamour Shots".

These speakers were sold to a gentleman in Moscow, Russia.   This next series of photos had me smiling from ear to ear!  It was very exciting to see my crate being opened up half a world away.  I could sense the anticipation on the other end as they were opening it up.

The crate wasn't designed to be on it's side, but I guess it worked fine.

The speakers arrived in perfect condition.  The crate was NOT opened during it's journey, which took about 2-1/2 months.

They had to go all the way up to the third floor.

Sergei is building a beautiful new home in a village just 15 miles from Moscow, right on the Moscow River.

Here, a worker is making one of the false corners.

Here they are in the listening room.  A temporary setup as the home is still under construction.

The buyer's first email to me after receiving the speakers:

Dear Greg,
At last today I received the Khorns!!!! everything went fine, it was easy to pick them up, then unload and bring them to the top floor. Now I'm listening to them - the sound is FANTASTIC!!! It is much better, than I expected. My cables are not very good, some adjustments are neccessary, but all the same, the Khorns are SUPER!!! and BEAUTIFUL!!!! Special thanks for so perfect package, and!!! the book!!! and assessories. I had no time to read the newspaper yet, first thing tomorrow(or today, since it is 3AM now). I cannot stop listening to my music which sounds absolutely different- much, much better!!!! As live music. I took some photos, I'll send tomorrow. The crate surprised everybody, so perfectly speakers were packed. And the book!!! I'll send photos tomorrow and thank You again!!! Best regards, Sergei

The newspaper Sergei is referring to is the Rolling Stone magazine that has "THE" Klipsch article in it.   The book is an autographed copy of the PWK Biography.

Overall this was a wonderful project to work on.  I can't thank Sergei enough, he was such a pleasure to deal with.  The results are what matter most to me.  I have a happy customer who's enjoying a pair of great sounding and great looking speakers.  I got to save another pair of Khorns and I made a few bucks doing it.

I appreciate that so many of you have clicked the email link below to let me know that you've viewed this webpage.

If you've viewed this page and would like to let me know, please send me an email.   No need to say anything, just click and send it.  Thanks.

Volti Audio - Klipsch Khorn V-Trac Upgrades and Restoration