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Music, Sound, Acoustics, Electronics and Physics for Car and Home Music Reproduction. From the fun stuff to the extremely technical; all for the love of music.

Soon after my arrival to England, we became acquainted. At the time they were supporting a competing importer. So our relationship was cordial but at arms length. Yet, things changed soon after I went to work for the company selling the products they promoted.
After my move, I started coming to their incredibly gorgeous country house to watch Formula One races. Yes, not much NASCAR over at the old continent. Inevitably, the subject of improving their cars came up. I am not one to make people spend money for the heck of it. So I advised to keep the general structure of the cars and simply improve the areas that were either seriously under-performing or that had never been addressed at all before.
Nonetheless, I ended up breaking my promise since I did modify their electronics. As everybody knows, improving existing electronics is an art with very few participants to call for help. And since it is such an important aspect of a good system, I cave in.
One of the problems often found with waveguides is the fact that it is hard to match their efficiency with that of most midbass systems. This is specially true when midbass drivers are placed on the doors. Considering an asymmetric seating position, which is normal in a car, it is inevitable to prevent synchronous right and left signals from canceling over a broad range of frequencies centered around 400 Hz. Bigger cars shift the cancelling range down slightly but still display the same phenomenon.
But what to do when you cover most of the musical range with incredibly well executed speakers? You match them with similar bass speakers located in the ideal location: the doors. To do this, the doors must be seriously rigid. We all have sat in cars where the doors vibrate. The feeling is terrible. Jay's car was the exception. This left the Dynaudio woofers to do their magic. When used in front of the listener, woofers tend to no longer bump. Listen to a high end home audio system, one where the speakers cost more than say $50,000. Notice that the bass is not the usual car audio bumpy sound. In fact, there seems to be no more bass; just instruments reaching all the way into infra-bass. This is why I love bass on the doors so much. It is so transparent that you can play it much louder in absolute terms and still sound boom-free. You see, bass in any other place in the car is coupled to the vehicle's surfaces and crevices. This coupling increases efficiency but at the cost of increasing audible color. Such color is what car guys recognize as bass. It is just that they have never heard real unamplified music. So, it is often hard to get this sort of bass to score as well as it should if other things are not in place. But when everything is right on, the degree of transparency leaves even the most skeptic of them all feeling a high degree of insecurity from daring to lower any of the sound scores. As a result, judges eventually come around.
In the case of Jay's car, both interconnects and speaker cables were over-built to display proper characteristic impedance and dampening factor. We made sure to reduce inductance in all cable applications to a minimum while keeping capacitance in check. Also, things like skin-effect-induced electron migration and quantum electron tunneling were deciding factors when selecting materials.
But the sound improvements actually started at the source. No, I am not talking about the head unit.
No, the source was instead one of the changers in the back. The transport picked the digital signal and, after buffering it with a high bias precision op-amp, it sent it away from the factory circuitry and towards a custom preamplifier located just two inches-of-wire away. The Lanzar six channel preamp was gutted. The larger than normal power supply was made more stable. Then, rather than using stereo op-amps, precision mono units where used.
This made the already quiet surface-mount Rockford amplifiers even more scary. It also meant that there was no Punch curve, Fader, Bass & Treble controls, etc., throughout the system, to damage the integrity of the music signal. The noise floor was also very, very impressive. Musical instruments would float in space surrounded by nothing more than the room they were recorded in. The short signal paths and attention to every capacitor, wire, inductor and connector detail resulted in waveguides that sounded smooth before being equalized. Anyone who knows about waveguides knows that these are beasts that must be tamed or else run the risk of constant threat. Waveguise love to eat listeners.

Why, then, is it that so many cars use the technique so successfully? Well, it all depends with what you call successful.![]() |
| Miniature Instruments |
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| Polar response for tweeters in "A" pillars and mids in kick panels |
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| Polar response for tweeter and mid in kick panels |
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| Polar Response at 10KHz between tweeters in the "A" pillars and kick panels |
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| Is Reflected Sound Evil? |
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| French Horns mostly do reflected sound |
Now let's go back in time to Dallas, Texas. Some time ago, James Feltenberger, the fabulous Dallas Symphony trumpeter, gave me the honor of listening to his fantastic trumpets played a few inches from my face. At the time, I anticipated getting my ears ripped off. After all James has quite the lungs and trumpets are often regarded as bright instruments. But to my surprise, I never reached anywhere near the threshold of pain. On the contrary, the sound was sweet and full-bodied.![]() |
| MBL 101 Omnidirectional Speaker |
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| Mies Van Der Rohe's Barcelona Pavilion |
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| Royal Festival Hall, London, UK |
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| Veritas Waveguide |
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| Double Slit Electron Experiment |
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| Construyendo un piso falso y los paneles para el sonido (abajo), López mantuvo la mayoría del espacio en el portaequipaje (arriba). |
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| López reconstruyo los paneles de las puertas cubriéndolas con un paño de lana y un vinilo gris. Cada puerta tiene un woofer de 8 pulgadas. |
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| Las redes pasivas de crossover para las bocinas en las puertas fueron montadas en la cubierta de atrás (abajo) y cubiertas con rejas (arriba). |
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| Caparazón construido a la medida para cada panel contiene un tweeter de 4 pulgadas, medio alcance y 0.75 pulgadas. |
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| Un lugar no muy común para poner los crossover pasivos. Bolsas pequeñas con cremalleras en las sillas contienen redes pasivas crossover para los paneles de las bocinas en el piso. |
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| Caja que se puede ver através debajo de la cubierta de atrás contiene dos subwoofers Dunaudio de 12 pulgadas. |
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| Piso falso en el portaequipaje tiene amplificador, equalizador y bloque de fusibles. El panel e la pared derecha del portaequipaje tiene una caja para los capacitores. |
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| La pared izquierda del portaequipaje tiene el Epicenter pintado a mano e interruptores. |
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| No estos no son de fabrica. López hizo al radio CD Denon parecer "Nissan." |
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| Diagrama del sistema. |
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| Cover Car Audio & Electronics Magazine Special Edition in Spanish |
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| Index Car Audio & Electronics Magazine Special Edition in Spanish |
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| Bajale al Boom Article Pages 48 and 49 Car Audio & Electronics Magazine Special Edition in Spanish |
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| Image of Bajale al Boom Article Page 50 Car Audio & Electronics Magazine Special Edition in Spanish |
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| Bajale al Boom Article Page 52 Car Audio & Electronics Magazine Special Edition in Spanish |
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| Bajale al Boom Article Page 54 Car Audio & Electronics Magazine Special Edition in Spanish |