Klipsch Forte IV loudspeaker

No one taught me more about the heralded tone of Ortofon SPU cartridges, the magical pacing of idler-drive turntables, or the dynamics and speed of horn-loaded speakers than Art Dudley, Stereophile's late deputy editor. His equipment reviews and monthly Listening columns weren't merely tutorials on how to review audio equipment with insight and an individual voice; they were also an entertaining, informative immersion into the kind of hi-fi he loved. We also shared many conversations, though too few.

Whenever Art lacked the time or interest to review a horn-loaded speaker, I pounced. Between May 2017 and August 2019, I reviewed the Volti Audio Rival, the Burwell Mother of Burl, the Klipsch Heresy III, and the Klipsch Forte III. In my review of the Forte III, I praised its reproduction of percussion, writing, "the entire drum set had its own distinct stage, each decay, cymbal ring, and drum resonance part of a larger percussive whole that poured forth from the Forte IIIs with exhilaration." The III offered solid "bass reproduction, some CDs or LPs creating visceral yet agile, creamy yet forceful" sounds. The Forte made the most of jazz trios: "I could easily hear the moments of contact between Ray Brown's fingers and his bass strings, [Shelly] Manne's sticks and drums, [Barney] Kessel's pick and guitar strings—those instants when action becomes visceral music."

The Forte IV
On its surface, the Klipsch Forte IV appears almost unchanged from its predecessor (footnote 1), and the IV's specifications are identical to those of the III. Both are three-way, horn-loaded, floorstanding loudspeakers. The frequency range of both is specified as 38Hz–20kHz, the sensitivity 99dB/2.83V/m at 8 ohms nominal impedance. The dimensions are very close: The IV is ¼" shorter (now 35.75"; 908mm) and 0.13" wider (now 16.63"; 422mm) than the III. Both are 13" (330mm) deep, and both weigh 72lb (32.7kg) per speaker. Both models come in American walnut, natural cherry, black ash, or distressed oak. The IV is priced at $4500/pair, $500 more than the III.


There are other important differences. On the IV, the high-frequency driver—a titanium-diaphragm, K-100-TI 1" (25.4mm) compression driver affixed to a 6" × 4" K-79T horn—has added an ABS phase plug "for a wider, more accurate sweet spot," Klipsch says. There's a new midrange: the Celestion-made K-702 1.75" (445mm) polyimide compression driver paired with a 10" × 7" K-703-M horn. The combination is said to ensure "exceptional detail and dynamics." The two bass units—the K-281 12" (305mm), fiber-composite cone woofer and, on the back panel, a KD-15 15" (381mm) passive cone radiator—are unaltered.

What else? Klipsch says that the 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 crossover network, Klipsch says, was influenced by the crossovers in the Klipschorn and the La Scala. "When I first came to Klipsch, Paul [Klipsch] was working on steep-slope networks," designer Roy Delgado told me during a phone call. "Paul evolved with his science on speakers. When he got the anechoic chamber, that created possibilities to get a lot more resolution. He would do tests and over the years update the networks, because he felt you would learn something new about the combination of drivers we had.

He felt that the weakest link was the crossover.

"We brought in the steep slope, which we also use in the Klipsch cinema speakers," Delgado continued, "because I wanted to make them efficient in their bandwidth; it also added a protection that wouldn't mess up the driver because of its strictly limited bandwidth. So, when we were redoing the Heritage series, I designed a steep slope crossover for the Forte IV." The specified crossover frequencies remain the same, and yet, Delgado told me, "The difference in the networks between the Forte III and Forte IV is not subtle."

I wanted to hear that for myself, so I wrestled the Forte IVs from their boxes, furloughed my DeVore Fidelity Orangutan O/96 speakers to the hallway, and pushed the Forte IIIs into the living room.

I used a variety of equipment in various combinations with the IVs, with Tidal streaming via Roon from my laptop to the preamp section of an Ayre EX-8 2.0 integrated amplifier (in for review). After that, the signal went either to the EX-8's amplifier section or to the LKV Research Veros PWR+ class-D power amplifier (specified at 200Wpc into 8 ohms). A 2m run of AudioQuest Forest USB cable connected laptop to preamp's internal DAC, a 2m pair of Triode Wire Labs Spirit II interconnects joined the preamp to the power amp, and an 8' run of AudioQuest Robin Hood speaker cables linked the IVs to whichever amplifier was in use. I used A/V Room Service Equipment Vibration Protectors (EVPs) under the IV's 2"-high support pedestal.

Listening inside the box
I immediately heard in the IVs a refinement and poise that the IIIs, for all their virtues, lacked. The IIIs have a little bit of the character of the fat-boy, low-rider Klipsch Heresys: energetic, dynamic, and just a little rough around the edges. The IV sounded smoother and richer than the III from the midrange through the upper treble, and the soundstage was deeper.

I listen to Fortes toed in so that they fire directly at my listening seat 66" away, with the speakers 61" apart on center. The IIIs could sound beamy in that configuration, but with the IVs,

I never heard that; instead, I heard a slightly wider soundstage and a more open, transparent top end. The IVs sometimes sounded a wee dark overall, which I didn't mind.

Footnote 1: The Forte III is still available.—Ed.
Klipsch Audio Technologies
3502 Woodview Trace, Suite 200
Indianapolis, IN 46268
(317) 860-8100

georgehifi's picture

"Inserting the Parasound Halo Hint 6 integrated amplifier (160Wpc into 8 ohms) brought further surprises. The soundstage was smaller than with the LKV Veros, but now everything on stage was more precise. I heard more top-end air, giving ride cymbals dimensional resonance and "ping," and acoustic bass notes sounded more concentrated, hence more emphatic."

This tends to be the difference I've heard when experimenting between the two different feedback configurations on SS amps I've made, when LKV is local feedback and the Halo is global feedback.

Cheers George

Jack L's picture


AudioBang's picture

I remember purchasing the original Forte after reading a positive review by the late Julian Hirsch when I was in my early twenties. Originally paired with a 60W Onkyo receiver, it was my first serious upgrade from a Heathkit AR2020 Quad receiver and four Radio Shack two-way speakers with 8" woofers. I bought a Crown Macro Reference for my bass guitar rig and later found myself on occasion pumping 600W/channel [according to the Macro Reference's power display] into the Klipsch's rated 96dB sensitivity playing the Back in Black album. It was so ear-bleeding loud it reminds me of the effect from the mind scanner on the original Star Trek "Dagger of the Mind" episode. I recall telling the salesman at the White Plains Lyric HiFi store how the sheer volume had the effect of purging the mind while making the hair on my neck stand straight up. He was setting up a Genesis V listening session for me and correctly remarked, "That's not what HiFi is all about". I remember the grin on my face when I responded, "Yeah, but I like it!"
Fast Forward to today, I'm reminded of Red's final parole hearing in Shawshank Redemption where he is asked "So do you think that you have been rehabilitated?" and Morgan Freeman replies, "That stupid kid is long gone [and this old man is all that's left...]" - I consider myself a young 59. Obviously those Forte did much more than this adolescent story I share.
I think of those original Klipsch Fortes with only fond memories like my first girlfriend. What a memorable product.

tsampson123's picture

Good review but a direct comparison of the Forte IV and Volti Razz is a
a missed opportunity! The difference in price is only $500 and a natural to have a reviewer's input on since the Razz rec'd a great review by you as well. Can you add a follow up please?? Thanks.

John Atkinson's picture
tsampson123 wrote:
Good review but a direct comparison of the Forte IV and Volti Razz is a missed opportunity!

The Razz has long since been returned to the manufacturer.

John Atkinson
Technical Editor, Stereophile

rlo's picture

Why no measurements with this one? Will they be provided later? Was very curious about the measurements for the IV vs the III.

John Atkinson's picture
rlo wrote:
Why no measurements with this one? Will they be provided later?

The report on the Klispch Forte IV was originally prepared and published in print as a Follow-Up and I don't usually measure products for Follow-Ups.

John Atkinson
Technical Editor, Stereophile

wilbur's picture

What review Is this a Follow-Up to? The Klipsch Forte III? Given that the high frequency drive is modified, the midrange drive is new, as is the crossover, and the comments in the review about the difference in sound between the two models, it seems like that's enough of a difference to warrant measurements of the current model.

Erin's picture

*cheap plug alert*
I measured this speaker and have the data here:

John Atkinson's picture
Erin wrote:
I measured this speaker and have the data here: https://www.erinsaudiocorner.com/loudspeakers/klipsch_forte_iv/

Thanks Erin.

John Atkinson
Technical Editor, Stereophile

Erin's picture

Glad to help. Was a bit worried it might be seen as "spamming" so I appreciate you letting the link stand.

wilbur's picture

Thanks, Erin! That was terrific.

tonykaz's picture

I'm supplicating myself in an attempt to have a pair of these Forte or Cornwalls.
Wifey would rather an attractive tiny transducers mounted on the floor behind the Sofa-Bed.
So I'll buy Abyss Diana & a high performance music system for my bicycle.
I don't have a basement to hide-away in.
Tony in Venice Florida
ps. if I lived in Europe my wife would love a nice MBL system
ps.2 ). Decades ago, I took a trade-in pair of Klipsch Corner Horns in Rosewood. hmm, can I get them back?

wilbur's picture

"...low end was full and weighty and, in my room, sometimes lacked a little definition. That would improve in a larger room..."

Ken, how large is your listening room? Thanks.

Wavelength's picture

I always found the klipsch horns a little off. Then someone told me pull the horns out and put modeling clay on the back of them so they don't vibrate because of the woofer. Man a completely different speakers. Hope you are well my friend!

ejlif's picture

nice. This seems like an obvious comparison. Chances of getting to hear both and then make a purchase decision seems unlikely for most.

dcolak's picture

Why do we see more and more "reviews" without measurements?

laxr5rs's picture

Thank you.

laxr5rs's picture

Get real here. Klipsch speakers usually measure horribly. Horrible measurements lead to horrible sound. What is the use of some writer with flowery words? Not much. You get a review with someone who's perennially over-confident in their severely flawed human hearing perception ability. Perhaps something like, "Hey, I liked them!" We should notice when cars are being measured no one says, "it measured horribly, but is fantastic anyway!" THAT'S what you get with "word reviewers." There's no use to this "review."

MatthewT's picture

feel sorry for you measurement geeks. I can see you at an art gallery with your colorimeter, bitching about that, never mind what you see.