After some waiting for Sonica 1’s PCB they have arrived. As usual, the quality was very good. I had made a few mistakes, but nothing serious. I will take a few minutes to explain what I had to fix and how the assembly and rebuild of the original amplifier went. The end result was as expected, no change in sound quality.
A month ago I started thinking about rebuilding my good old headphone amplifier with TPA6120A. I didn’t realize it was that old until I decided to translate the original article in English. It’s been 7 years and I though it was 3 or 4. Time passes quickly, it seems. I spent some time thinking how to improve it. Now the PCB and components are ordered and once I get them, assembly will take place in the same chassis. What’s new and improved? A number of things in fact.
The list of updates is as follows:
- Single PCB to include all blocks except input and output connectors
- Encapsulated toroidal transformer for PCB mounting
- Double the capacitors in the regulator (2x2200uF for each polarity)
- All electrolytic capacitors are now Panasonic FR series (newer and better than FC)
- All 100nF decoupling capacitors are now polyester WIMA MKS02 (smaller, allowing them to be closer to TPA6120A). Not as great as the polypropylene Panasonic, but more than sufficient
- ALPS Blue Velvet potentiometer
- New heatsinks for the voltage regulators
- All possible components switched to SMD
- Rectifier diodes changed to 2A model
- Delay On circuit has now its own voltage regulator
- Delay On circuit error fixed – output was switched off when the large capacitors discharged, now this happens when the switch is turned off (well, around 50ms later)
- Delay setting trim potentiometer is replaced with Bourns precise model for easier setting of desired delay
- Power LED will now turn on and off together with the headphone relay
- The new PCB has option for 115V in addition to 230V (supported by the new transformer)
- New volume knob
Let’s take a closer look at the design decisions made, updates and why they were needed.
Continue reading “Sonica 1 – Headphone Amplifier With TPA6120A Part I – Schematic And PCB Design”
Somehow I forgot to translate this second part of the Headphone Amplifier project from Bulgarian to English. Better late then never 🙂 The project has been finished in March 2010 and all relative time references should be linked to that date. That was quite a while ago. It seems I have lost track of time or I’m just getting older. I am building an updated version at the moment and I will post an article about it soon. Now let’s go back to the finishing of the first version.
Time has come to finish the project, started long ago, headphone amplifier with TPA6120A. After I finished the assembly of the PCB for the amplifier and performed some tests in August 2009, I just didn’t have an opportunity to finish what I have started. Now everything came in its place and one PCB became a finished product. The final version combines the amplifier together with toroidal transformer, voltage regulator and circuit for delayed output enabling in a nice aluminum enclosure. Continue reading “Headphone Amplifier With TPA6120A Part II – Finished Product”
Recently I started updating my sound and home cinema system. Most of it of course I bought from different shops, but some things I like to do myself. It saves money sometimes and counts as a hobby. What did I do? Well, I didn’t have enough time to design and build my own amplifier or another pair of nice speakers, so I ended up making my own speaker cables. What’s so special about that? You just get some cable, strip the ends, put it in the screw terminals on the speakers and the amplifier and you are done, you say. Not when you try to achieve high performance. Here is what it looks like.
It isn’t very difficult to make such nice looking cable and it saves money. Continue reading “Hi-End Speaker Cables”
Two years after the beginning of my MLTL speakers project with Jordan JX92 it has finally come to an end. I made some finishing touches but nothing significant. The speakers now are freshly painted, has new spikes and second pair of terminals are added for choice of connection schemes. The photos following show the finished speakers.
My MLTL speakers project with Jordan JX92 was waiting for final touch with some paint or veneer, but it ended up with HiVi Research RT1.3 ribbon tweeters instead. As good as JX92 are, we all know that there is nothing perfect. It was absurd to think that 4-inch driver is capable of reproducing 30Hz perfectly and it is the same with the high end of the audible spectrum. That is why I decided to add ribbon tweeter to improve the highs after I cut the bass port to improve the lows, sacrificing those below 40Hz. The good thing is that I chose project which allows me to add second driver – second generation 35″ MLTL. Although I didn’t use Aurum Cantus G2 as Jim Griffin did, the final result is OK with me for now. The photo below shows the tweeter already mounted in the speaker. Its front panel isn’t the most beautiful but at least it sounds good.
After a long pause it is time for something new in simple my web site. At one moment in time I decided to make some good speakers, which will be pleasant for listening and at the same time cheaper than a small car like those you can buy in audio shop. I chose the notorious JX92s by Jordan. This small driver is widely used in DIY as well as commercial speakers. After half year thinking over countless enclosure designs I ended my search at Jordan’s website and its second generation 35″ MLTL.