The loudspeaker has not changed much in concept since its earliest days. Improvements have been made and new configurations developed, most significantly the line array in recent years. But developers and engineers still strive to find the next move forward. Among them is George Krampera, who, over a long career in pro audio at several big name companies, continues to pursue the best possible sound.
This quest led to him establishing KV2 Audio, which has eschewed the line array trend to produce single-point source cabinets. Based in the small Czech Republic town of Milevsko, in southern Bohemia approximately an hour and a half ‘s drive from Prague, the company is based on chief engineer Krampera’s philosophies of sound. It began in the early 2000s with the ES Series, which was followed by the smaller ESD and EX ranges, the K-RIG, the large-scale SL and the high performance VHD touring and installation series.
Further evolution came this year through the VHD5.0 constant power point source array and the ESD Cube ultra compact passive loudspeaker. Krampera says it was his ambition to have his systems, particularly the VHD5.0, sound like tube technology. His fascination with this old tech goes back to his youth, when his father worked as a technician. “I was born around tubes,” Krampera explains. By the age of 10 he had built his own radio set and at 14 made power amps for local Prague bands.
While Krampera enjoyed a successful career designing audio equipment in Czechoslovakia (as it was then), the political situation there led him to leave the country with his family in 1983. After a short time in Austria they moved to Canada, where Krampera worked at Yorkville Sound, designing not only guitar and keyboard amps but also processed loudspeaker systems.
Later he ran his own company, Rexx, but returned to Europe in the early 1990s and took up a job at Italian loudspeaker manufacturer RCF. From 1991 to 1998, Krampera worked to improve RCF’s transducer design and also conceived the ART series of active speakers. When the company was bought by Mackie, he left to join fellow Italian manufacturer B&C Speakers, where he continued his work on transducers.
At the end of the ’90s, Krampera returned to what had become the Czech Republic and set up audio design firm Class A. Later he and former RCF colleague Marcelo Vercelli established a new company, FUSSION. The company’s large-scale speaker system then came to the attention of Greg Mackie, who invited Krampera to rejoin RCF. During his second period there Krampera continued to work on the FUSSION range and designed loudspeakers for Mackie.
Staying with RCF until 2001, Krampera teamed up again with Vercelli to launch KV2 (the ‘K’ standing for Krampera, the ‘V’ for Vercelli and the ‘2’ signifying it was their second venture together) in 2002. Working in a small cottage in Milevsko, he began designing what would become the ES Series. Vercelli left the new company in 2005, after which Krampera’s son, George Junior, became chief executive. Part of his brief was to expand KV2’s market reach. A significant element in this was moving to a new factory in 2009, which allowed for more centralised design, manufacture, testing and administration.
Originally a shirt sewing factory during the Soviet days, the cottage has been fitted out in an ongoing, staggered programme over the years. Dedicated areas include the paint shop, a sample workshop and mechanical and software design departments. The cabinets are handmade from Baltic birch, although routers and CNC machines are used. Toroid coils are wound on the premises, which Krampera Junior says “has a massive effect on the sound.” Components and finished cabinets are tested in a special area containing acoustic treatments and a microphone to measure frequency performance. “It’s all about the testing and we have very strict tolerances,” explains Krampera Junior.
This applies equally to the electronics for the amplifiers, with test equipment designed in-house and dedicated burn testing areas. Electronics assembly is again by hand, although a wave soldering machine is used for the circuit boards and is the only mechanised part of the process.
There is an in-house R&D department but George Krampera Senior has his own lab, which his son describes as his father’s “play room”. This features a selection of technologies, including old reel-to-reel tape machines and CD players, plus a full selection of KV2 systems, doubling as a demo area until a permanent area is built. Next to this is the top of the company’s anechoic chamber, which, at 10x10x10 metres, is claimed to be the biggest in Europe.
All of this embodies what KV2 director of sales David Croxton calls a “unique approach” to loudspeaker technologies. Croxton is a 30-year veteran of pro audio and helped establish an international distribution network in Europe and the Americas. Leading sound designers – including Bobby Aitken, Richard Brooker and John Shivers – have specified KV2 systems on major productions such as Cirque du Soleil, Kinky Boots, Mamma Mia! and Fiddler on the Roof. KV2 is also seeing uptake in territories outside traditional territories. “We’ve been very successful in the third world and developing countries,” Croxton explains.
Croxton comments that live sound has largely been based on the idea of “more is more”, resulting in ever bigger rigs. In general, it is KV2’s aim to have fewer boxes making up a rig, regardless of the venue size. “Because we’re doing point source type systems, less equipment is required to cover an audience area,” says Croxton. “That leads to a lower capital outlay, which is a better return on investment. One of the reasons we’ve grown so dramatically in the theatre market is that we can provide a high quality production at a considerably lower price point than our competitors. Not because of using cheap components or electronics but because we do it with less equipment.”
KV2 sees this as helping lower installation costs, while its rejection of DSP for tuning systems results in shorter set-up times. This is a major difference between KV2’s approach and that of line array companies, which use DSP programmes to tune their equipment.
Among Krampera’s criticisms of line array technology is that the time-shifts involved in a multi-point source results in the sound from the different elements arriving at different time. (Although line array developers have always maintained this is controlled by ‘coupling’ the cabinets to produce a single output). “Line arrays did improve the sound but introduced destructive interference between the sources,” Krampera says. “The biggest problem is the movement of air, which is a fluid medium. Point source systems are more resistant to changes in air movement.”
Krampera and Croxton are equally critical of the systems that went before line arrays; stacks of different cabinets that were put together to throw out as much sound as possible. Looking at the VHD5 in particular, there is the thought that point source is a different way of doing what had been done in the past with bin and horn systems. Krampera stresses these are two different things: “They were multi-point sources and had problems with air movement with acoustic pressure turning to heat, which loses the high frequencies. Our horns are very shallow and do not suffer losses like that.”
Another element that KV2 sees as an improvement over other types of loudspeakers is its use of trans-coil technology – or active impedance control – for its transducers. “Transducers increase the force of the speakers and the sensitivity,” says Krampera. “And because there is only one source, it cannot be cancelled out.”
The transducers play a key role in what KV2 claims is a new standard for live sound: SLA (Super Live Audio). This comprises: Super Digital (based on the Super Audio Compact Disc – SACD – format developed by Sony and Philips as an audiophile version of conventional CD), which has 20MHz sampling for extreme resolution, more than 120dB dynamic range and low non-harmonic distortion; Super Analogue, with super-fast circuitry (including a settling time of 1μ) and an ultimate headroom of 200kHz; and Super Acoustic to offer a true point source with active impedance control and low distortion.
One of the aims behind SLA is to reproduce high sound pressure levels in large areas, while maintaining dynamic range and source representation. Another is to deal with what Krampera sees as the limitations in source material, including the mixing console, which he feels has not benefited from the move to digital. SLA utilises the Direct Stream Digital (DSD) technology in SACD as its conversion process to increase the sampling rate (encoding at 2,822,400 samples per second), thereby improving the audio quality.
“I don’t hate digital,” Krampera concludes, “but mixing desks really stopped developing in the 1970s, apart from just adding faders. With all the technologies we’re using we have ended up with a system that is loud and sounds like a tube, although it is solid state.” Whether or not KV2 can turn the tide against line arrays, Krampera can certainly say he has stayed true to his audio and technological roots.