Rolf Gemein: the Heart of the Matter
I'm not sure why, but people tell me things. Maybe it's because they realize I listen. They reveal themselves, sometimes in charming and unexpected ways. So I was almost prepared for my three-way conference call with the designer of the Symphonic Line Kraft 400 power amplifier, Rolf Gemein, in Germany and Indianapolis-based importer/distributor Klaus Bunge. I started by asking Rolf about his design philosophy:
Rolf Gemein: Hi-fi systems in general are not able to reproduce natural, live sound. We're not even getting close to the intimate experience of an opera house, for example. There are three inherent problems in reproducing a musical experience through a hi-fi system:
First, the vast majority of amplifiers and loudspeakers don't distribute the energy correctly. There is enough energy in the bass frequencies, but this energy is somewhat lacking through the mids and the highs. However, the human ear is used to the large amount of energy that musical instruments can producelike a trumpet, for instance. Most hi-fi systems can produce the tone of the trumpet, but not the necessary energy.
Second is the phasing. Correct time coherence of all frequencies is inherent in music. This means that the sound of a human voice, for example, is time-coherent in all frequencies in a waveform that in itself is a specific time unit. Most hi-fi systems rip apart the timing of a tone into a slower bass frequency and faster high frequencies. So the sound pattern is unnatural and can't be identified correctly.
Third, the sound pattern must have a comprehensible body, which should create a visual illusion of a certain instrument. As transducers, loudspeakers have to make place for emotions. The radiation pattern of each frequency determines whether or not a tone is free and airy in the room, seemingly out of nowhere, or if it seems that there is a music system playing. And you know, the research can't be done alone with measuring instruments.
In fact, at this time there are no suitable instruments for measuring these very complex correlations. They can only be grasped and interpreted with the ear and a sensitive nervous system.
Jonathan Scull: [Usually more talkative] Uhhhhh, huh.
Gemein: Then and only then can one transfer the emotional results, so to say, into the technical side of it, and not vice versa. Once all these three factors act in unison, a natural and three-dimensional sound pattern can be possible.
Scull: As I understand, you place great importance on equal energy distribution throughout the frequency range.
Gemein: To come even close to the musical reproduction of a live experience, a power amplifier must evenly distribute a tremendous amount of energy, far and above the normal listening spectrum, with absolute and correct phasing with no distortion. For instance, internationally there are a great number of very powerful amplifiers on the market. It is, however, common knowledge that the smaller amplifiers produced by these same manufacturers sound much better. So, the bigger brothers do something wrong. Why?
Scull: [laughing] I was just about to ask!
Gemein: [laughs] Ja, first of all, it is because of the general layout of an amplifierespecially the size of the output boards. If you throw away all the advantages of a small, compact board layout and distribute the signal path over a square foot or two, sonically most of the fine inner details are simply gone to hell. This is the reason why we have invested so much time in bringing down the size of the main output board to an extremely small 5.6" by 6".
Anyway, for a truly natural reproduction, you can't do without pure class-A operation. We're talking true, natural sound here, not just the hype and marketing opportunities of class-A. Feeling this way, I have searched a long, long time for the perfect heatsink. To the best of my knowledge, our customized heatsink holds the world record. It has the sensational K-value of 0.1!
Scull: Wow! A K-value of 0.1! Rolf...what the hell does that mean, please?
Gemein: [laughs] It's very easy. You can say this special aluminum heatsink allows for about three to four times better heat dissipation than, say, those of Krell and Levinson.
Scull: Okay, I'll buy that.
Gemein: This incredible heatsinkor each individual 'sink let into its structuremade it possible for me to run the amp in pure, high-bias, class-A operation without fans or other tricks. We incorporated the same excellent, very fast pre-driver transistors we use in the smaller Symphonic Line units. Most of the other powerful amplifiers on the market resort to bad-sounding, sluggish transistors so they will be stable under high voltages. And, very important: I'm using a type of capacitor that has been produced specifically for Symphonic Line. It has a totally even distribution of energy, without favoring any specific frequency. Internally, we also use special Symphonic Line cables and an extremely rare kind of silver solder.
Scull: Tell me, Rolf, what drove you to make these statement amps, the Kraft 400s?
Gemein: You know, as long as I've been doing hi-fi, I've had the feeling that, in existing amps, there's something like a brake that holds back the energy necessary to make a total, complete sonic picture. Especially the energy in the region where people think you don't hear it, like over 20kHz. Believe me, to get it right way out to there, you can't have enough power. If I could, Jonathan, I would build my amps three times as big to get even more class-A out of them!
Scull: I see...(I see Rolf is having a breakdown. Just kidding!)
Gemein: You see, it's a real important part of reproduction to make the sound palpable, realisticto make it emotional. To achieve this, it's important to consider what is beyond the range of human hearing. This beyond 20kHz range is the most difficult and most overlooked area. This is how you will notice the art of the amplifier designer: by their handling of the region beyond the human ability to hear. This includes not only frequency, but also coherency of phasing and time, distribution of energy, and any distortions up there.
Scull: All right. Anything you'd like to leave us with? Besides a huge electric bill?
Gemein: I will tell you about something very important to me, and this is the first time I'm saying it officially.
Scull: [To Kathleen Benveniste] See? They tell me stuff!
Gemein: I believe every living thing on earth has its own resonance factor. For a human, it's the heart chakra. If you're a designer and you take this into account, you can be successful no matter if you are making a speaker, an amp, or a race car. That is, if you're capable of hitting exactly this pointthe heart chakra. Then everything can resonate, perfectly balanced on all sides.
Then you'll succeed, because the whole universe, everything around us, is perfectly balanced and working on the same basis. Like our solar systemthe sun is the chakra, and everything else is perfectly balanced in their orbits around it. That's my way of thinking, and it defines my approach to the entire situation.