DIY audio blog for projects, schematics, PCB's, designs, electronics, mods


Simple JFET Preamp

A JFET preamp for beginners. Simple yet elegant. Low noise.

The following is an example for a very simple and high quality JFET preamp. You can use this to amplify a very low signal sources. FET transistors are usually not used independently in preamplifiers. In most of the cases they are paired with bipolar transistors.

simpe jfet preamp

Soft start, Speaker Protection by Audio Workshop

Soft start. Speaker Protection. Speaker Delay

Soft start. Speaker Protection. Speaker Delay

We have completed this module this week. It is a custom build by order of a customer. The module has many specific functions. It can be used for speaker protection, speaker delay, toroid soft start and others.

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.

Page 3 of 11

Powered by WordPress & Theme by Anders Norén