 |
 |
 |
|
|
Brief History of Solidyne
The invention of the bar-graph displayAbout Solidyne...
The
invention of the digital VUmeters
|
|
|
The original invention arises in 1959, before Solidyne was founded. We have been working in film sound recording. This technique uses a light beam moved by means of a galvanometer. The control of the peaks of audio was very strict and the needle VU meters do not have enough fast action. Then, a system of optical lens was necessary to set the correct recording level, using a microscope of difficult reading, to see the light beam. The solution we found was an electronic system, without mechanical parts, formed by 10 steps marked in decibels. We created therefore the first light bar VU meter, without inertia and over impulse, that measures the true peak of the audio signal |
|
 |
Since LEDs had still not been invented, each indicator was illuminated by a small neon lamp; that was placed in the back part of the VU meter and was handled with 250 volts from a tetrode tube. |
|
From 1962 we replaced the neon illuminators by incandescent lamps used in telephony, of very long useful life. You can see in this console of 1967 the use of bar graph VU meters, which were excited by transistors |
 |
|
| At the beginning of the decade of 1970 Solidyne manufactures equipments with the new bar VU meters, like this audio compressor for AM radio. |  |
|
| The indication of the input and output levels, as well as the compression level, was given with great exactitude by the bar graph VU meters. The scale was linear in dB. For that time no other manufacturer of the world used this technology |  |
|
|
When reliable LEDs reaches the market, we start manufacturing the 3rd generation of bar graph displays; that were used in 16 and 24 channels consoles for recording studios, as this unit of 1976 | |
 |
This console 2000X of 1978, for 16 channels recording, uses a complete turret with 24 VU of modular construction, that supported different ways of reading (peak, average, rms) At that time, our patent was expired, and this device began to be used for a lot of companies of USA and Japan, in professional products and home audio. The manufacturers of integrated circuits began to produce units to excite the LEDs. |
|
 |
At this moment, the evolution of our ideas derives in the concept of the Integrated Display VC180, which indicates not only the peak level of a stereo signal but the stereo Vector of Phase. Available from 1997 to the present time, this technology allows the user interpreting an audio signal in a total way.
|
