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Art For Engineers


Well mandala-1we all like and enjoy beautiful things of life. Art is a fine example. Engineers however are a kind of  different animals. They enjoy looking at bizarre things. I do as well. What you see on the right is a fine example. A “painting” made out of electronic elements. Almost every possible type of electronic device is used and I think it’s amazing.

No deep thoughts about this. I’m not an art expert. Some might find it ugly, some might find it strange or whatever. I just wanted to share this with everybody.

If you like this be sure to check out this website.






Original and Reproduced Audio

Define Original and Reproduced musical and audio contents

reproduced_soundIn general we listen to musical performances in two basic ways. The first one involves an actual attending to real live music events (a concert, an opera, ballet music festival etc.). In this case the musical content we perceive is called ORIGINAL musical (audio) content (OAC), unlike the REPRODUCED musical (audio) content (RAC), which we perceive by using electronic and electro-acoustic devices. For the purpose of this article I will use the terms original audio content and reproduced audio content.

The reproduced musical contents are generally divided by two groups depending on the time we listen to them.


The first type is the so called synchronous audio contents. Those we get when we listen to any LIVE broadcasting over the TV, radio and live internet streams. This type of musical content is characterized by the fact that it occurs simultaneously with its original prototype but at a different place.

Unico CD Primo. High Fidelity of High Pleasantness?

unico_cd_primoSo it was a pleasant weekend. Just a few folks gathered together to listen to some good music. Well not only. It’s always about listening to something in particular and test it against something else. In this case one of the guys had brought his beloved CD player – the Unico CD Primo by Unison Research.

Well I had to say that I was rather suspicious about this testing. The first thing is that this CD player has a really good looking tube output stage. Having noticed that it was clear that this fellow has nothing to do with the neutral and transparent sound. However I kept my thoughts to me and we all sat down and listened.

Grounding System In Power Amplifiers

Here is a very good schematic showing a tipical power amplifier grounding system. I have tried it ina many of my projects and it works every time. No hum, no ground loops no noise. Dead silent. Of course a proper power supply routing on the main PCB is critical. If done properly some very very high performance could be achieved.

Update 18.10.2014

The schematic was proposed by D. Self in his book “Audio Power Amplifier Design”. For any further info, please check out his work.

Power Amplifier Design by P. Baxandall Part 2. Negative-feedback Concepts.

In the January issue the concept, and possible consequences, of slew-rate limitation were discussed, with particular reference to one cause, in which the first stage of an amplifier is unable to supply the current demanded by the collector-to-base feedback-stabilization capacitor in the second stage. With suitably modified circuit designs such effects may be made insignificant. Before specific circuits are discussed in later articles, the present article will deal with some basic ideas about negative feedback and transfer functions.

Baxandall power amp design part2 – >>>LINK<<<

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