Thoughts on Forte's

[dougdrake]

Edster - Thanks for the tip. I know I'll immediately want them when I do, and then we'll have the domino effect again - Fortes to another room where the KG4s are, the KG4s to the bedroom where the KG3s are, the KG3s to the kitchen, and on and on

Actually, I had the chance to pick up a pair of Cornwalls recently, but I just don't have the floorspace for them the way our living space is laid out. So for now, anything bigger than Forte is out of the picture (although I am eyeing some Chorus's).

[Cruzer]

Go for the Chorus!!!!!! You will love them!!!

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Cruzer

[aabernathy]

Doug,

I'm glad you purchased the Fortes. Are they the original Forte or Forte IIs? I have modified several of these great speakers and have finally reached Forte "nirvana". Take those beauties and fill the base with sand and enclose with a false bottom. Next, replace the interior wiring and upgrade the x-over network with new caps and inductors. Thanks to AL Klappenberger's advice, I finally found the magical mix (Hovland caps, Harmony Bypass cap, Solen litz air core inductor, and Solen solid wire inductors). To top it all off dynamat and mortite the horns and woofer cages. What you end up with are the most hot rod pair of Fortes around. The differances are astounding. I have a pair that are left unmodified so that I can remember how they used to sound. Basically, what I'm saying is if you like them now, just wait. Update your resting beauties!

[dougdrake]

EEGADS, Aabernathy - You'll notice that my postings are conspicuously absent from any of the technical discussions on this board (LOL)!!! I was following you up to the part about filling the bases with sand and putting in a false bottom. From there on out, I'm in the ditch.

To answer your question, they are Forte Is.

[aabernathy]

Doug,

In that case, just enjoy! The original fortes are my favorite, so you made out like a bandit. If you ever get tired of those guys just let me know.

[Steve Phillips]

Hey Andrew are the unmodified Forte's the ones you got from me?

[aabernathy]

Hey Steve,

No, your old fortes are now my heavily modified pride and joys. They were great before but now they are just more...well it's hard to describe in words...transparent, dynamic, accurate. You know what I'm talking about you have done all of these mods to your Khorns, minus the sand in the base. The x-over mod had the most profound effect.

[dougdrake]

Of course you realize, Andrew, that now you've planted the seed of "what if." Knowing I could have supercharged Fortes, and not doing anything about it, is going to kill me.

I could probably figure out the electronic part of what you were describing with the help of a friend (are you reading this, Ross?). But would it be worth just doing the non-electrical mods - the sand and the dynamatting?

Doug

[aabernathy]

Doug,

I know how you feel. I was content with the Fortes before I found this BB, now I can't stop thinking about ways to improve my setup. Welcome to the obsession. To answer your question, yes, I think the non-electrical mods were beneficial. The sand in the bass, although subtle, does appear to have given a little more accuracy in the bass department. It tightens it up a little.

I used mortite on the tweeters and squawkers and dynamat on the woofer and passive cages. This mod seems to have mellowed the highs out. This is also a subtle mod. I'm not thoroughly convinced that plastic horns need this level of dampening. However, I have had several different pairs of Fortes and repeatedly I continue to do this mod. Remember that obsession thing. Because at this time you already have the horns out of the speaker enclosure it is best to go ahead and replace the internal wiring to whatever wire you use from your amp. No reason to use great wire from your amp only to get to the x-over where less desirable wire connects to the drivers. I use Silver Sonic Q-10 on the bass and T-14 on mids and highs. This mod has a very noticeable effect. I highly recommend doing this mod. The result was a better soundstage, imaging, and overall accuracy. You do have to use a soldering iron for this mod, but it is great practice for what is to come with the x-over mod. I think the nonelectrical mods are subtle but when you combine them together they are noticeable and desirable.

The Fortes, like most Klipsch, are very sensitive to the equip they are used with. The best mod I ever made was purchasing a new amp from Enlightened Audio Designs. Although the x-over mod is a close second. You can do these mods. If you want I can send you detailed directions on how to perform each one, just let me know. If I can dig them out of my Klipsch File, which is now overflowing, maybe I'll post them here on the BB.

It's frustrating knowing that your speakers could sound better isn't it! Let the games begin.

[dougdrake]

Andrew - I'll take this under advisement. Haven't held a soldering gun since I was a kid, when my dad and I put together a Heathkit engine test meter and a timing light. (He built a Heathkit tube "mono block " amp before that, without me. Wonder what that would sound like today??)

I'll let you know if I need more info. A couple of questions, now, though. What is mortite? Is it a cousin of lesstite? And where do you find it? Also, regarding the sand in the base, does it need to raked in a certain direction, and do the silicon crystals need to be oriented towards Hope, AR? (Just kidding about the sand...).

Doug

[cyberman9000]

Can you post the crossover mod or send it to me? Thanks, Trip

[aabernathy]

Sorry, guys. I left town for a couple of days and did not get a chance to check back with this topic. I will post detailed instructions tomorrow for those mods.

[aabernathy]

Ok Guys and hopefully gals,

I have had so many e-mails on the subject of Forte mods that I have decided to post them as promised on the Klipsch BB - so here they are. Depending on free time I will post one today and a major one tomorrow.

In and effort to tighten the bass on the Fortes, I placed sand in the riser bases and created a new bottom. Some people use spikes, but I have beautiful hardwood floors that I didnt want to mar.

Forte Mod # 1

Materials All materials were purchased at a local Home Depot.

1. Clear Silicon for caulking gun

2. 36 - 1 1/2 wood screws

3. 36 ¾ wood screws

4. 7 ½ of oak 2 X 1 wood

5. 2X4X1/4 Red oak plywood (Home Depot lists this as ¼ B-4 Rot Red Oak 2X4 CFP)

6. 20lb bag of horticultural grade sand (playground sand)

Instructions

Note: After reading through instructions please recheck measurements. This was written down from memory, although I have performed this mod on seven different sets of Fortes.

1. Flip the Fortes over so that the riser bases are facing up and you can see inside them.

2. Cut the 7 ½ of oak wood into eight pieces (Four that are 13 and four that are 8 ½ long)

Use the 1 ½ screws to secure these pieces of wood one at a time into the interior walls of the riser bases making sure that the 2 side is flush against the riser wall.

3. So, looking down into the riser bases you will see the 1 side facing up toward you make sure that this side is flush with the top of the plastic corner braces of the riser base. This is done so that the plywood you are going to use, as a bottom will sit level on both the plastic corner pieces and the rails you have created. You are securing the rails through the 2 sides into the riser base walls.

4. Silicon the interior cracks where the riser base meets the speaker and the riser base corners. Smooth with finger.

5. Cut the plywood to make two pieces that measure 15 X 10 ½. The 2 X 4 plywood will make four of these bottoms, so go buy more Fortes to modify.

6. Fill riser bases with sand and level with a ruler so that the top of the sand is level with the top of the rails and corner joints.

7. Place plywood piece in place and use smaller screws to secure in place. Secure plywood piece into the rails that you have created. This creates a bottom that should be completely flush with the Forte riser bottom.

8. If you are a real anal retentive, obsessive compulsive Klipsch freak like me, you can even stain the plywood bottom so that it matches your speaker cabinets - although no one will ever see it.

9. Silicon the cracks between the riser base walls and the plywood bottom to keep the sand from leaking.

10. Let dry. Turn the speakers over and enjoy until the next rainy day when you can tackle the next mod.

[aabernathy]

After finishing the last post, I realized that I did not mention that these mods are all viable for the Forte II and the Chorus series. The only exception to this is the x-over mod, where the values of the caps and inductors would change. I highly recommend calling Klipsch and asking them for the schematic on whichever one of these speakers you have.

The next couple of mods involve opening up the Fortes by removing the passive radiator, woofer, mid horn, tweeter horn, and speaker wire post box from the speaker cabinet. Simply unscrew the Phillips screws that hold these items in place and gently remove. It is easiest to perform all of these mods at the same time, so that you do not have to continuously remove these items.

The first of these mods was to dampen the horns and woofer cages. I used rope caulk (mortite) on the tweeter horn and sqwuacker horn. On the woofer and passive radiator cages I used dynamat.

It is my belief that whatever speaker cable you use, especially if you use higher end speaker cables, that you should replace the internal factory wiring from the x-overs to the drivers with that wire. This holds truer on the older Klipsch models. I use silver sonic Q-10 from my amp, so inside the speaker I ran silver sonic T-14 to the mid and tweeter and I used Q-10 to the woofer. I also soldered these wires in place using a silver solder from Welborne Labs. There are wire harnesses on the sides of the cabinet that can be used to restrain the wires and prevent them from slapping the cabinet.

The last and final mod to my Fortes was to replace the caps and inductors on the x-over. The parts cost $108 per speaker. It is important that you not be overwhelmed by this step. I knew very little about soldering or x-overs, but it really was not that difficult. Much credit must be given to Al Klappenberger, who over the course of time has answered many of my questions and after much experimentation had already comprised a magical mix of caps and inductors for his AlK networks. I simply borrowed his selections and applied them to my speakers. For the Forte these are:

From Madisound at madisound.com

One-1uf Hovland cap

Two-1.5uf Hovland caps

From North Creek at northcreekmusic.com

One-1uf Harmony Bypass cap

From Solen at solen.ca

One-3mh 10 gauge air core litz wire inductor part # 103.0

One-.16mh 14 gauge standard wire inductor part # S14.16

One-47uf Solen Fast cap part # PA4700

The difficulty with the x-over mod for the Forte comes from the fact that the inductors are too large to fit on the area where the old x-over was mounted (the back of the speaker terminal posts). Therefore, you need to cut a new board that will fit down into the speaker case right behind the old x-over. I cut one that was 4 X 8. Take a look at Als at www.web-span.com/alk/klipsch.html. The screw down posts and barrier block if you choose to use them can be purchased at Radio Shack. Essentially all you are doing is recreating the x-over on the back of the Forte terminal post onto your board. You will have to borrow the autotransformer from the old network. The Harmony bypass cap is to be used in parallel with the Solen Fast Cap. Al recommends using a silicon glue to attach the caps with flexible leads to the board, so that they will not vibrate. I used wire harnesses on the inductors that secured though pre-drilled holes in the board. Once you have completed your new network, according to the schematic and simply by glancing how the old one was put together, you will need to mount it inside the cabinet. I used L brackets and screws. Next, solder you internal speaker wires in place onto the network. You will need to remove the old components from the speaker terminal posts back and solder speaker wire from the back of the posts to the network. Of course, I used silver Sonic Q-10 for this. Finally, screw everything back in place, pick your favorite song and get ready to be blown away. Remember, there is a little burn in time involved.

If you need the values for the Forte II, I have those as well, but I believe it is in your best interest to ask Klipsch for the schematic.