Monday, August 31, 2015

A Family Business

Imagine doing what you love with those you love. That was the case of the Bow family. Jim (dad), Geraldine (super mom), Jay (son) and Sasha (daughter) made up the most competitive sound off family in the United Kingdome. Their love for music was only matched by their love for their family.
When I entered the picture, they already had two very competitive cars that were winning right and left. Jay competed with his Ford Escort while Sasha run her Peugeot through the lanes. Both were very good. 
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.
Since I had completely fallen off the installation wagon, I was not to touch their cars. All the installation had to be done by someone else. It is a real shame but the name of the installer escapes me. If you know the name, please share it with me so I may give him proper credit.
So, I was simply to design and to instruct the work. Then, when finished, I would help with the tuning. 
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. 
As the days and weeks passed, the cars begun to take shape. Jay's Escort matured tremendously from a very good car to an incredible one. 
Jay added waveguides. Lots of work had to be done to make their mounting surface rigid. Rigidity is something often overlooked by most, so called, professional installers. Many improperly confuse resin-over-felt with fiberglass, for example. They miss the fact that their concoction is missing the whole 'fiberglass' thing. just because the resin hardens into a glass looking rock, they think that it is the right stuff. Let's make it clear. if you take glass that is shaped as short strands and then you apply as little resin as possible, you now have fiberglass and not resin-ed felt. By the way, resin is a plastic.
These lost souls also miss the natural rigidity of fiberglass; especially when used as a constriction layer within a composite structure. When rigidity is done well, speakers that already display a high degree of transparency become as airy as the best electrostatics or plasma drivers. Of course that tuning the mouth of the waveguides following the art-form initiated by the Holdaways was key.
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. 
As should be expected, cancelling midbass at 400 Hz, just an octave below the crossover frequency of most waveguides, renders the combination useless at best. To solve this, we designed a system where the path length of the midbass drivers was greatly increased. This reduces the amplitude of the cancellation and moves it to a much lower frequency; one that can be much more effectively dealt with through the use of a rigid and well sized enclosure. But since the ideal location needed to satisfy these goals was the floor of the car, using an exceptional speaker with a low physical profile lead us to the incredible Dynaudio speakers. Too bad that this manufacturer seized to sell their raw drivers to the many high end enthusiasts who revered them.
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.
To make all these speakers work, we deployed the best in conductor material and cable geometry I knew at the time. I know that many car guys think that car-wire is more than enough and that there is no right argument for the use of expensive home cables. I agree with them that I too don't like to pay a lot for anything. But where we disagree is on the issue of giving up performance just because the good stuff is more money than the garbage. I have conducted dozens of blind audience listening sessions where neophytes had to identify A or B in an A, B, C comparison. While they were often unable to eloquently explain the difference in performance, what they could easily see was the fact that there was a difference. So much for expert disagreement. 
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. 
Then came the electronics. I already said that everything was hot-rodded. If I only told you that the 30 band Lanzar equalizer operated at such high bias that it run very hot to the touch at all times. Translation, this close-to-class-A performance made the eq very sweet. It was very much like a tube equalizer would sound. 
But the sound improvements actually started at the source. No, I am not talking about the head unit. 
There was none. There was only a display at the dash and a pair of door-mounted controls anywhere near the listeners. 
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. 
The high power supply rails and their low impedance made it possible to operate the opamp at an insanely high voltage output level. We are talking well into the double digits and without attenuation throughout the system components. The motorized volume controls were placed right before the amplifier's pre-drive. 
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.
Well, not in Jay's car. His sound was as smooth as that from the best softdomes. No matter how much each equalizer band was increased or decreased, the constant system characteristic was that of total smoothness. Yes, rare indeed!
As I left the British kingdom to pursue other goals, things went very well for the cars at first. Unfortunately, the family later went through tragedy. Geraldine, the gravitational center of the family's soul, passed away. This broke everybody's heart, but specially those from her husband and kids. For all of us, Geraldine was as warm and mild as anyone can be. For her family, she was as stable and robust as the time-tested Greek columns that still support the Parthenon. No one like Geraldine.
Jim moved with the kids to his homeland of Australia. The love for each other remains strong, just as mom would have wanted it. But their sound-off years went to become just a memory; albeit a fantastic one. The Bow's will for ever be my friends no matter where they live. The three of them and their mom are perpetually in my heart.








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