Klipsch Forte IV

Floorstanding Speakers - Pair

Klipsch Forte IV

Floorstanding Speakers - Pair
From $4,998.00
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Overview

First introduced in 1985, the Forte quickly established itself as the most popular Klipsch model. The elegant design and outstanding performance made the Forte a standout among its competitors. In 2017, Klipsch re-introduced the Forte as part of the Heritage speaker series. The new Forte IV features updated cosmetics and the latest advancements in acoustic engineering while maintaining the original charisma that made the Forte so popular.

Sold as a pair.

Model: 1069161

The High Notes
Built on Tradition

Built on Tradition

You’ll get 75 years of Klipsch tradition in the Forte IV. This revised new model is made to sound more like the speaker that started it all, the classic Klipschorn. Experience more of the sound Klipsch lovers rave about with the Forte IV.
Let It Rock

Let It Rock

When you are ready to bring the concert home, crank up the Forte IV. With their ability to produce astounding loud full-range sound free of distortion, the Forte IV will make you think the band followed you home. Plus, they are so easy to drive, it only takes a small amount of power to get them rocking!
Proudly Crafted in the USA

Proudly Crafted in the USA

Own part of a legacy from the craftsmen at Hope, Arkansas with the Forte IV. From book-matched veneers to meticulous hand assembly, these are made with pride by people who have been making heirloom speakers for decades.

Company & Product Overview

The year 2021 is going to be very special to the folks at Klipsch as it represents their 75th anniversary. In 1946, Paul Klipsch sold his first speaker out of a small tin shed in Hope, Arkansas, and launched what has become one of the world’s most popular speaker brands ever. Back then, Paul enlisted the help of a local cabinet maker and the Baldwin Piano Company to produce the first few speakers, before hiring his first full-time employee. Today, that original location is the home to the Klipsch museum, and Klipsch employs hundreds of music-loving people while being sold all over the globe.

Paul Klipsch believed in 4 design principles that lead to his first speaker, the Klipschorn. Those are high efficiency, low distortion, controlled directivity, and flat frequency response. Every Klipsch speaker made today still adheres to those same guiding principles and if you ever visit their headquarters in Indianapolis, you’ll see them everywhere!

old school photo of Klipsch
old image of Paul Klipsch

To celebrate the 70th anniversary of Klipsch and due to huge demand from their fans, Klipsch introduced their Heritage series in 2016. The Heritage models brought back new and improved versions of most of the original Paul Klipsch designs and made Klipsch fans all over the world very happy! The Forte III was added to the Heritage lineup in 2017.

To celebrate their 75th anniversary, Klipsch is introducing a new Forte model, the Forte IV. We thought it would be fun to take a dive into what makes up a Forte speaker and do a comparison between the current Forte III and the new Forte IV.

When we first got word of the upcoming Forte IV, we got Klipsch to agree to send us a pair to play around with before their introduction. We will first go over the basics of the Forte model, then go over the improvements the Forte IV offers. Then, we’ll let you in on what our ears experienced when we compared the two models for ourselves.

Design and Build Quality

Most of the early Klipsch speakers were known for being quite large in physical size as it does take a large cabinet to have a complete horn-loaded design. The Forte was introduced in 1985 and was a great way to get that classic Klipsch sound in a much smaller cabinet. The Forte went on to become one of the most popular Klipsch speakers ever made but was discontinued just five years later in 1989.

When you look at a Forte next to the top of the line Klipschorn, there is no question, it is far easier to fit into a room than the Klipschorn, La Scala, or Cornwall. Those models have quite an imposing footprint with big sound to go along with their large size.

Even though the Forte stands at 3’ tall, the ratio of its dimensions (only 13” deep and about 17” wide) gives it a smaller look that enables it to fit into most living rooms. We think it is the best value in the Heritage series as it too can sound very big and powerful, yet can blend into a space far easier. Just make sure and have some help around for your new pair as they are 72 pounds each out of the box!

forte iv finish options

You have four choices of finish on the Forte IV with grills designed to match each one. They are American Walnut with Salt and Pepper Grille Cloth, Natural Cherry with Salt and Pepper Grille Cloth, Black Ash with Salt and Pepper Grille Cloth, and Distressed Oak with Lambswool grille cloth. Our favorite is the Oak with the light-colored grill as it just has this classic retro look we feel is fitting for a speaker with a 75-year heritage.

All of the Heritage series models are made in the USA at their Hope, Arkansas factory. There, skilled craftsmen, who in some cases have been with Klipsch for decades, make each and every Heritage model by hand. Each pair is serial number matched just like the book-matched real wood veneers that grace the speaker cabinets. A pair of speakers even travel together through the factory to assure you get a beautifully matched pair of speakers. You can rest assured, a Klipsch Heritage speaker will last a lifetime and be something your next generation will likely enjoy as well.

klipsch forte iv oak lifestyle

Features & Technology

The Klipsch Forte IV is a 3-way design with a horn-loaded tweeter, horn-loaded midrange, and 12” woofer on the front of the cabinet. The rear has a 15” passive radiator.

The Forte IV is rated at a 99dB sensitivity which makes it a super-efficient speaker. You can drive these with anything from a tiny tube amp to a big McIntosh or Mark Levinson solid-state amp with no issues. With the ability to output an SPL level of 116dB, these can rock!

Starting with the tweeter, the Forte IV uses a titanium compression diaphragm driver coupled to a patented Klipsch horn. All tweeters like to beam as the frequencies increase. Klipsch has updated the phase plug to improve the linearity of the high frequencies. In effect, it ensures controlled uniform directivity all the way up to the high frequencies. This has a dramatic positive effect on sound staging.

forte iv american walnut front

The midrange compression driver is a new model using a polyimide diaphragm. This driver was developed for the recent Cornwall IV. We were curious as to what exactly a polyimide was and did a little digging. It turns out to be a pretty exotic plastic polymer that has a very high resistance to heat. Polyimide is used in high-tech military applications and high-temperature fuel cells. The midrange driver is coupled to a modified Tractrix® horn. The horn uses Klipsch’s patented Mumps tech which gives you extremely even sound in the listening area.

The 12” woofer is made of a fiber composite cone material. To extend the bass even deeper, Klipsch adds a rear-mounted 15” sub-bass passive radiator. Passive radiators enhance the bass from the active woofer. The Forte IV gets down to 38Hz. We also love the solid binding posts on the rear that are big enough from some massive speaker cables and are set up for bi-wiring if you wish.

forte iv rear

Klipsch decided to voice the new Forte IV more like their top-of-the-line Klipschorn and La Scala speakers. These use a steeper slope than the other models and are used in the Forte IV. They also upgraded the quality of the components used in the crossover. While you never see a speaker crossover, it is a critical link in the chain as it splits up the incoming signal and sends different frequencies out to the drivers. A cheap or poorly designed crossover can ruin the sound of a speaker. From the tech used in this new crossover network, it appears to be first class.

As you might expect from a Heritage series Klipsch, the cabinet is very solidly built, in the case of the Forte IV it is made of ¾” MDF, then the matched veneers are applied.

Technical Differences in the Forte III and Forte IV

We love the fact that Klipsch, like just a small handful of other speaker manufacturers who actually make their own speaker drivers, spells out the actual driver name they use for the speaker components. This makes it easier to compare model to model and to see what they have changed when a model is upgraded.

Tweeter
Both the Forte III and Forte IV use the K-100-TI 1” titanium diaphragm compression driver on a K-79T horn. The phase plug was changed on the Forte IV for more linear high-frequency dispersion.

forte iv horn detail

Midrange
This is where there are some big changes as the new Forte IV uses the same compression driver developed for the more expensive Cornwall IV. The driver is the K-702 model while on the Forte III they use the K-70 model that uses a titanium diaphragm as compared to the polyimide material on the K-702 version. We should point out Klipsch also uses polyimide for the tweeter diaphragm in the La Scala and Klipschorn. Both the Forte III and Forte IV use the same K-703-M horn.

Woofer and Passive Radiator
These are both identical on the Forte III and Forte IV.

Crossover Network
Klipsch made some big changes here, using both more expensive components in the crossover network and changing the slope to more closely match what they do in the La Scala and Klipschorn. The crossover points remain the same at 5.2kH and 650Hz. It appears the goal was to get the sound of the Forte IV to be closer to a Klipschorn!

Cabinet
While the Forte IV is ¼” shorter in height than the Forte III, this is due to the redesign of the base the speaker sits on. All new Forte IV color versions have the same matte black base.

Performance Testing and Comparison

We set the Forte IV and Forte III up in our listening room to test the Forte IV and how it compares to the Forte III. We did an asymmetrical setup so each speaker would be the same distance apart and in our rectangular room would be just a mirror image on distances from the side walls.

We pulled them off the wall about 25” and used a tape measure to get them exactly the same for both models. To power them we used a McIntosh stack consisting of their MT5 turntable, C-49 preamp, MC152, and MCD350 CD Player.

It is always important when comparing things to perfectly match levels, which was a cinch with these two as they are identical in sensitivity.

We decided to make this an all-analog comparison and pulled out some classic records from years gone by, which of course plays right into the legacy behind the Forte. For our testing, we listened to one of our all-time favorites the Getz/Gilberto with The Girl from Ipanema, the Amanda McBroom Dreaming Album, a very old Direct-Disk of the Neophonic String band, and finally the Persuasions No Frills album.

You probably noticed a focus on midrange here, which is where we expected to hear most of the improvements in the new Forte IV. First, it is totally clear the Forte IV is an evolution of the Forte III. The sound profile between the two is similar, but the differences we heard were pretty big to our ears.

On the Getz/Gilberto we heard a big difference in just how much more effortless the voices and saxophone sounded on the Forte IV. When we flipped back to the Forte III, they almost sounded strained.

The title cut Dreaming was even bigger. Her voice floated in space and sounded very natural on the Forte IV, and when we switched back and forth to the Forte III, we felt her voice had almost a coloration to it. We actually had to do a double-take and pull the grills off to make sure the horn itself was not different on the two as it sounded like we were hearing some horn resonance on the Forte III in comparison. Our theory is the new midrange driver and steeper crossover slopes are a much better match to the horn itself.

Next up were the Persuasions, who are an acapella group, and we heard the same differences in the midrange improvement but even more so with multiple voices going on.

On every single cut we had tried up to this point, the stereo image was also wider, deeper, and more precise in space on the Forte IV. But when we switched to the next album, that difference became huge.

The Neophonic String Band is a great old bluegrass record. On the Forte IV, everything was perfectly in space, spread out very well. When we switched back to the Forte III, it was like the image just went back into the two speakers.

Needless to say, we were very impressed with the new Forte IV. We did not even cover here how both models have great bass impact and have such a high sensitivity, you can run them with a very small amp.

We have to give Klipsch some kudos for taking a speaker that was already really good and making it much better in our opinion.

klipsch forte iv lifestyle

Overall Recommendation

The Klipsch Heritage Series covers a wide range of prices from the Heresy to the top-of-the-line Klipschorn. With the new changes, the Forte IV sounds a lot more like the top-of-the-line Klipschorn than it did before. We think this probably makes it the very best value in the Heritage Series and should be on the list of anyone who wants to recreate the feeling of a live band in your home. And what music lover would not want to do that!

Details & Specs

HIGH EFFICIENCY, HIGH-PERFORMANCE LOUDSPEAKER

The Forte IV hosts a three-way design utilizing a 12” woofer and horn-loaded midrange and tweeter. The Forte IV incorporates an all-new K-702 midrange compression driver, featuring a polyimide diaphragm for exceptional detail and dynamics. The K-702 midrange is mated to a modified Tractrix® horn — featuring Klipsch's patented Mumps technology for even polar response of mid frequencies, giving you more consistent sound throughout the listening area. The titanium diaphragm high-frequency driver has an all-new wide dispersion phase plug for providing exceptionally even high-frequency dispersion for a wider, more accurate sweet spot.

PASSIVE RADIATOR YIELDS FULL RANGE PERFORMANCE

The Forte IV’s well-extended bass is found in the use of a rear-mounted passive radiator. A mammoth 15” (38 cm) in size, this sub-bass radiator operates on acoustic pressure generated by the active woofer for greater bass output and extension.

NETWORK

The Forte IV has been completely revoiced from its predecessor, utilizing premium componentry in an all-new high-fidelity network — minimizing electrical degradation throughout the circuitry — for truer to life sound with best in class efficiency and power handling. The new network draws from the classic three-way steep slope design of the legendary Klipschorn and La Scala speakers.

BI-AMP INPUT PANEL AND BINDING POSTS

The Forte’s premium, aluminum input panel accommodates large, high-quality speaker cables. Strong, versatile, and quality binding posts provide the capability for bi-wiring or bi-amping.

BOOK-MATCHED WOOD VENEER

Klipsch only uses book-matched wood veneers for the Heritage series. The veneer leaves are kept in order as they are delicately sliced from the timber and precisely arranged to provide a mirror image at the splice joint — like turning the pages of a book. This gives each speaker an aesthetically appealing and consistent appearance that is treasured more than any other cut of wood veneer.

MATCHED PAIRS

Every pair of Heritage series loudspeakers are grain-matched using wood veneer panels that come from the same timber. Each cabinet is carefully matched so that each speaker in the pair is practically indistinguishable from the other. The speakers move seamlessly together through the factory, and each finished product is inspected and labeled with sequential serial numbers, ensuring that your Heritage series speakers leave the factory as a meticulously crafted set.

BUILT TO LAST

While each and every component of the Forte IV is built to last, Klipsch has always recognized the unique and critical role of a loudspeaker’s cabinet in the sound reproduction process. From the craftsmen in Hope, AR to the engineers in Indianapolis, IN, Klipsch has always put an extraordinary emphasis on cabinet design. The Forte enclosure is assembled using only the highest-grade adhesives and fasteners. This is a speaker you will hand down from generation to generation.

FREQUENCY RESPONSE (+/- 3 dB) - 38Hz – 20kHz

SENSITIVITY* - 99dB @ 2.83V / 1m

POWER HANDLING (CONT/PEAK) - 100W / 400W

MAXIMUM SPL - 116dB Continuous

NOMINAL IMPEDANCE - 8 ohms Compatible

CROSSOVER FREQUENCY - 

  • HF: 5.2kHz
  • MF: 650Hz

HIGH FREQUENCY DRIVER - K-100-TI 1” (2.54cm) Titanium diaphragm compression driver on a K-79T horn

MIDRANGE - K-702 1.75” (4.45cm) Polyimide Compression Driver mated to a K-703-M horn

LOW FREQUENCY DRIVER - K-281 12” (30.48cm) Fiber-composite cone woofer, KD-15 15” (38.1cm) Passive cone radiator

ENCLOSURE MATERIAL - 3/4” MDF

INPUTS - Dual binding posts / bi-wire / bi-amp

HEIGHT - 35.75” (90.81cm)

WIDTH - 16.63” (42.24cm)

DEPTH - 13” (33cm)

WEIGHT - 72 lbs (32.7kg)

*Sensitivity in average listening room


Reviews

Customer Reviews

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m
m duke
great speakers

bought a pair of klipsch forte 11 in 1986 for 1300.00 a pair. still going strong. don't know what they are worth but have been offered more than i paid for them. will not part with them. GREAT SPEAKERS