Just How Good Can a 75-Year-Old Design Really Sound in 2025?
For years, I thought my hi-fi journey had reached its end. My system felt completely balanced, expressive, and capable of everything I asked from it. Then, I met the Klipsch Heresy IV. What began as curiosity quickly turned into revelation. Few loudspeakers manage to rekindle the excitement of first discovering high-fidelity sound; the Heresy IV not only did that it redefined what I thought I knew about dynamics, immediacy, and musical presence.
Heritage and Design
The Klipsch Heresy name stretches back to 1957, when Paul W. Klipsch sought to create a compact center channel speaker for the Klipschorn. When his team questioned why he’d design a sealed box speaker instead of a horn-loaded one, his tongue-in-cheek reply was simple: “Because it’s heresy.” The name stuck — and so did the spirit of rebellion that has defined the Heresy line ever since.
Now in its fourth generation, the Heresy IV blends mid-century charm with modern engineering refinement. The cabinet is beautifully hand-finished in book-matched real wood veneers, available in walnut, oak, cherry, and black ash. It retains the familiar angled riser base and retro silhouette, but subtle updates, including a rear Tractrix port, modernize both looks and performance.
At 24 inches tall, it’s compact by Heritage standards, yet radiates the same craftsmanship you find in the larger Forte IV and Cornwall IV. Brass nameplates, magnetic grilles, and solid cabinetry remind you that this is a product designed to last for decades, not just seasons.
Technical Breakdown
The Heresy IV is a three-way loudspeaker featuring a 12-inch fiber-composite woofer, a midrange compression driver coupled to a Tractrix horn, and a titanium diaphragm tweeter also horn-loaded. For the first time in its lineage, Klipsch introduced a rear Tractrix port, transforming low-frequency behavior while maintaining the taut, rhythmic qualities fans love.
Internally, the crossover network has been redesigned using audiophile-grade components and air-core inductors. The nominal impedance remains 8 ohms, and the sensitivity, a staggering 99dB at 2.83V/1 m, means the Heresy IV can be driven effortlessly by as little as a few watts from a quality tube amp. Yet it scales gracefully with powerful solid-state amplification, revealing layers of texture, air, and control.
The frequency response is rated at 48Hz–20kHz (±4dB), but don’t let the numbers fool you: the Heresy IV’s presentation is all about speed and presence, not subsonic rumble. Bass is lean but articulate, and every note is delivered with conviction.
Setup and Placement
Placement with the Heresy IV is key. These speakers are designed to sit low on their risers, angling sound slightly upward toward the listener. A modest toe-in of around 15–20 degrees tightens the imaging beautifully. While they can sit close to the wall thanks to the controlled porting, a bit of breathing space (say, 8–12 inches) allows the midrange to open up and bloom naturally.
In smaller rooms, their forgiving dispersion makes them remarkably adaptable. In larger spaces, they scale with surprising authority. Whether paired with a 300B SET amplifier or a high-current solid-state integrated amplifier, they convey music with immediacy and realism that borders on live performance.
Listening Impressions
Once connected, the Heresy IV doesn’t just play music, it performs it. Vocals leap forward with tangible presence; brass instruments blaze with texture and bite; drums have the snappy impact that startles you out of routine listening.
On acoustic recordings, the Heresy IV captures the breath of the performer and the shimmer of strings with unfiltered directness. Jazz and classic rock feel like they’ve been given new life. Snare hits snap, guitars growl, and pianos carry a percussive clarity that feels utterly alive.
What sets the Heresy IV apart is its dynamic honesty. It doesn’t smooth over transients or soften edges. Instead, it exposes the raw energy of the performance, not harshly, but truthfully. At lower volumes, it retains body and excitement; at higher levels, it turns your living room into a stage. It’s the kind of experience that makes you rediscover your music library, track by track.
Comparisons & Context
Compared to the Heresy III, the IV represents a significant evolution. The rear port adds much-needed depth and warmth to the low end, while the new crossover smooths the transition between drivers. The soundstage is broader and more coherent, imaging sharper and more refined.
Versus its larger siblings, the Forte IV and Cornwall IV, the Heresy IV is more intimate and focused. It may not plunge as deep in the bass, but its speed, clarity, and rhythmic drive make it addictive. It’s the most fun-sized member of the Heritage family, ideal for rooms where the Cornwall might be overwhelming, but where you still want that unmistakable live Klipsch sound.
Verdict and Conclusion
The Klipsch Heresy IV is not just another loudspeaker; it’s a statement of what makes hi-fi thrilling. It embodies the rebellious spirit of its founder, balancing heritage craftsmanship with modern acoustic refinement.
I genuinely thought my system was complete. The Heresy IV proved otherwise. It reminded me that great audio isn’t about perfection, it’s about emotion, energy, and engagement. Every note feels alive. Every listening session feels personal.
If you believe your system no longer surprises you, the Klipsch Heresy IV might just reignite that spark.
Klipsch Heresy IV Specifications
| Feature | Specification |
|---|---|
| System | 3-way, rear-ported loudspeaker |
| Frequency Response | 48Hz – 20kHz (±4dB) |
| Sensitivity | 99dB @ 2.83V / 1m |
| Power Handling | 100W continuous / 400W peak |
| Nominal Impedance | 8 Ohms |
| Drivers | 12” woofer, 1.75” midrange compression driver (Tractrix horn), 1” titanium tweeter (Tractrix horn) |
| Crossover Frequency | 850Hz / 5kHz |
| Cabinet | MDF with real wood veneer |
| Dimensions (H × W × D) | 24.8” × 15.5” × 13.25” (631 × 394 × 337 mm) |
| Weight | 45 lbs (20.4 kg) each |
| Finishes | American Walnut, Natural Cherry, Black Ash, Distressed Oak |
Pros & Cons
Pros:
- Legendary live, dynamic sound
- Superb efficiency pairs with tubes or solid-state
- Beautiful handcrafted cabinetry
- Upgraded ported design improves bass depth
- Immersive and engaging presentation
Cons:
- Bass extension is still limited versus floorstanders
- Not ideal for listeners who prefer ultra-smooth, laid-back tuning
Final Verdict:
The Klipsch Heresy IV is a timeless loudspeaker that bridges vintage soul with modern precision. It’s bold, emotional, and unashamedly alive proof that “finished” systems can still surprise you.
