Klipsch Forte IV crossover values - Chart

[Dave C]

Anybody know who manufactures Klipsch capacitors?

 

[Tom Brennan]

Since the speaker was voiced with its existing crossover can't "improving" the crossover degrade the intended sound?

I heard the new Heresys the other night and was very impressed with the sound and I hate the old Heresys. If the new Fortes are akin to the Heresys I'd just leave the goddam things alone. You Klipsch guys just have to screw around even when the speakers sound great, eh?

 

[BigRiver]

Since the speaker was voiced with its existing crossover can't "improving" the crossover degrade the intended sound?

I heard the new Heresys the other night and was very impressed with the sound and I hate the old Heresys. If the new Fortes are akin to the Heresys I'd just leave the goddam things alone. You Klipsch guys just have to screw around even when the speakers sound great, eh?

Absolutely -- it can 100% degrade the existing sound; it can also improve it, it can also be a lateral move to a different but perhaps not better sound, it can also do absolutely nothing.

I get the "leave the damn things alone" mentality, I tend to leave some higher end things alone.

However, Klipsch is not one of these things and has a history of significant performance gains both through upgraded crossover components as well as proper bracing. I can tell you that the Forte iv's are great, but I can hear the cabinets vibrate with a tiny Sherwood s5000 integrated.

I think it's cool that you like to keep things as they are, many do and can be happy with it, kudos.

Then there are those who savor the process of experimenting on, making mistakes/having successes with and ultimately understanding in a different way the things they choose to fill their lives with.

 

[BigRiver]

Anybody know who manufactures Klipsch capacitors?

See automojo -- response #11 in this thread.

 

[twiiii]

Well it makes it easier for me to understand why the new series IV is a better sounding speaker system than previous models. Shown here is a very sophisticated crossover yielding great results from a much improved midrange and tweeter assemblies.

 

[BigRiver]

Well it makes it easier for me to understand why the new series IV is a better sounding speaker system than previous models. Shown here is a very sophisticated crossover yielding great results from a much improved midrange and tweeter assemblies.

It is my understanding that the Forte iv and the Forte iii both use the K-100-TI 1” Titanium diaphragm compression driver on a K-79T horn, although I think they did add a phase plug The mid driver is new and the crossover completely reworked to voice it closer to the bigger Heritage speakers.

 

[SitBack]

Thanks OP for providing X-Over resistor values. I ordered Vishay 1% Wire Wound 10 watt resistors from Mouser Electronics. Mouser had 13 ohm resistors but no 8 ohm and no 5 ohm resistors. I parallel connected two 16 ohm resistors for each 8 ohm spot and two 10 ohm resistors for the 5 ohm spot. I took me an hour to remove and replace the resistors. In addition to removing and replacing the resistors, I applied Kilmat Sound Deadening membrane to portions of the cabinet interior, midrange horn, bass drive frame and passive radiator frame. I removed the steel lock washers and steel nuts from a pair of input jacks and replaced those two pieces with brass washers and brass nuts. Lastly (since bi-wiring is not an important feature for me), I removed one pair of input jacks and I combined the two sets of input wires to a single pair of input jacks.

 

[BigRiver]

Nice work SitBack. I think getting those resistors replaced was a good call, this crossover project should be coming up soon and I have also considered dampening the horns and spiders. The resistors appear to have gone on really clean, they look great. Do you think you will do any further updates? I have heard that the v-cap odam capacitors are excellent in the Cornwall iv's and expect that since the voicing is so similar in the Forte iv's that they may be a good choice here too.

I reached out to Klipsch to ask for inductor values, but he was definitely not going to give them to me, but did end up having a nice exchange none-the-less. Although as an engineer on this project he was less than thrilled to hear I was interested in upgrading some of the passive components.

Thanks for sharing and posting pics, hopefully I will be adding some before too long as well. Would definitely be interested in any thoughts you might have as to changes due to your work on them if the chance arises.

 

[SitBack]

Thanks to you, BigRiver, I was inspired to modify the Forte IV’s.

What helped to make the resistor removal and replacement project so easy was how closely the Vishay/Dale 10 watt, 1%, wire wound resistors match the size of the stock resistors. One goal of my Forte IV x-over project was to work within the footprint of the original x-over circuit board. The limited real estate of the original x-over circuit board prevents me from considering installing the much larger air core inductors and high performance capacitors. For now I am stuck with the stock iron-core inductors and entry level capacitors.

My description of the input jack mod is unclear, so here are images of modifications of the input jack connection.

The modded Forte IV’s initially sounded a bit congested/compressed. As I get more playing time on the speakers, I note that they are beginning to open-up and are becoming a more enjoyable listening experience.

 

[r100tsl7]

I just scored a used pair of these forte 4's. Very nice job. I noticed the crossover pics so I looked at mine. I think the crossover is very good quality but I need to get those small caps replaced by some soviet oils and aluminum foils which sound excellent to me. I was surprised to see the smaller inductors were not air core. It wouldn't have been that difficult to mount those.
If anyone has a schematic it would be nice to see. I'm not tempted to rebuild the entire thing since aircore inductors will most likely have different dc resistance values and may throw the steep slope circuit off. They sound fantastic as is. Probably just the three smaller caps and perhaps any small inline inductors to the mid horn where in my experience the majority of the music is and the most sensitive part of human hearing. Many heresies have shown me that as I figured out crossover mods.