Klipsch Heresy
1957 – Present
Klipsch designed the Heresy in 1957 as a center channel speaker for Klipschorn stereo systems. The name came from Paul Klipsch himself, who considered it "heretical" to build a Klipsch speaker that didn't use a corner horn. It became a popular standalone speaker anyway, and it remains in continuous production, which makes it one of the longest-produced speakers in history.
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Specifications
| Type | 3-way, acoustic suspension/sealed enclosure |
|---|---|
| Woofer | K-22 12" (30.5cm) fiber-composite cone |
| Midrange | K-55-V, K-55-X, or K-53 2" (5cm) phenolic diaphragm compression driver on K-700 or K-701 exponential horn |
| Tweeter | K-77, K-77-M, or K-77-F 1" (2.54cm) phenolic diaphragm compression driver |
| Crossover Frequencies | Low-Mid: 600-700 Hz, Mid-High: 5000-6000 Hz (varies by generation) |
| Nominal Impedance | 8 Ω or 16 Ω (early models) |
| Power Handling | 100W continuous, 400W peak (vintage models rated at 105W) |
| Sensitivity | 96-99 dB @ 1W/1m (varies by generation) |
| Frequency Response | 50 Hz – 17 kHz (±5 dB, vintage models) |
| Dimensions | 21.375" H x 15.5" W x 13.25" D (54.3 x 39.4 x 33.7 cm) |
| Weight | 75 lbs (34 kg) per speaker |
| Enclosure Material | Birch plywood with book-matched wood veneers |
| Finish Options | Walnut, Cherry, Black Lacquer, Raw Birch (HBR) |
Design Overview
The Heresy breaks with the fully horn-loaded approach of the Klipschorn. Paul Klipsch needed a compact center channel that could sit horizontally between two Klipschorns. So he gave it a sealed enclosure and a direct-radiating 12" woofer (the K-22) in place of a horn-loaded 15" woofer.
The midrange and tweeter are still horn-loaded, like the rest of the Heritage series. The K-55 compression driver on its exponential horn gives exceptional clarity and presence. The K-77 compression driver handles the high frequencies in detail. The bass is direct-radiating and the midrange and treble are horn-loaded, and that mix gives the Heresy a unique sonic character.
The sealed enclosure (acoustic suspension) gives tight, controlled bass, even with a smaller woofer and cabinet than the Klipschorn. The angled front baffle is meant for horizontal placement as a center channel. Many owners run Heresies as standalone stereo speakers anyway.
Generational Evolution
- Heresy (1957-1985): Original design with Type E crossover, K-22 woofer, K-55-V midrange, K-77 tweeter
- Heresy II (1985-2005): Updated crossover, improved K-22-E woofer, new grille design
- Heresy III (2006-2019): Major redesign with new drivers, thicker cabinet walls, slant riser for vertical positioning
- Heresy IV (2020-Present): New K-107-TI titanium tweeter, redesigned Tractrix horn, rear port for extended bass
Historical Context
Stereo recordings became popular in the mid-1950s, and owners of Klipschorn-based systems needed a center channel speaker for phantom center imaging. Paul Klipsch designed the Heresy for that job. It matched the efficiency and tonal balance of the Klipschorn and was compact enough to fit between the main speakers.
Paul's own view was that a Klipsch speaker without horn-loaded bass was heretical, and that is where the name comes from. The speaker sold well enough that it stayed in production long after its original purpose became less relevant with the rise of discrete multichannel audio.
Over the decades, the Heresy built a reputation as a superb near-field monitor and small-room speaker. It is efficient, compact and has exceptional midrange clarity. Audiophiles with modest amplification and listening spaces took to it.
The Heresy has seen a resurgence in popularity in recent years as vintage audio enthusiasts discover it. Well-preserved vintage pairs, especially consecutive serial number models, command premium prices on the used market.
Special Versions
- Heresy HBR (Raw Birch): Unfinished birch plywood cabinets, often oiled or left natural
- Industrial Heresy: Black painted finish for commercial installations
- Heresy 1.5: Transitional model between Heresy I and II with some updated components
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Listening Impressions
The Heresy is renowned for its exceptional midrange clarity and presence. The horn-loaded midrange driver delivers vocals and instruments with a palpability and immediacy that few other speakers can match. While the sealed 12" woofer doesn't reach as low as larger ported designs or horn-loaded speakers, the bass it does produce is tight, articulate, and well-integrated with the midrange.
The Heresy excels as a near-field monitor or in small-to-medium rooms. Its high efficiency (96-99 dB) means it can be driven to satisfying levels with just a few watts, making it an excellent match for low-powered tube amplifiers. Many owners pair vintage Heresies with vintage Marantz, McIntosh, or Dynaco tube amps for a classic high-efficiency system.
Documentation
- Heresy IV Technical Specifications (PDF)
- Klipsch Heritage Series Brochure (PDF) - Includes Heresy information
- Official Heresy Product Page
External Resources
- Klipsch Museum of Audio History - Official museum in Hope, Arkansas
- Klipsch Audio Community - Official forums and community
- HiFi Engine Heresy Manual - Scanned original documentation
Related Models
- Klipsch Belle (1985)
- Klipsch CF-3
- Klipsch CHORUS
- Klipsch Cornwall III (2006-)
- Klipsch Cornwall IV
- Braun AUDIO-1 (1965)
- Braun AUDIO-250 (1965)
- Magnavox Component Systems (1972)
- Acoustic Research AR (1967-1976)
- Acoustic Research 11