Bartekh, Brisbane (2026)

09/04/2026

With the ground loop issues resolved, I moved into deeper testing to see what was limiting performance.
One thing that surprised me was just how much the power supply was affecting the amplifier.

When running the amplifier from a lab supply, I measured an SNR of around 109 dB. However, when switching back to the original PSU, performance dropped noticeably. The main issue was ripple and supply noise (primarily around 100 Hz) coupling into the signal path.

It also became clear that I had not spent enough time ensuring truly clean rails for the preamplifier and input stages.

For this reason, it was back to the drawing board. In this newest iteration, it had the three big improvements:
1. Added RC decoupling networks:
These help isolate the small-signal stages from the high-current output stage, reducing ripple and preventing supply noise from modulating the signal.
2. Introduced dedicated regulated rails (+15V, +24V, -15V):
This provides much cleaner and more stable supply for the preamp and control circuitry.
3. Improved thermal design of the rectifier stage:
Added large copper pours on both sides of the PCB with thermal vias to better dissipate heat from the bridge rectifier diodes and improve long-term reliability.

This iteration should significantly improve noise performance. This means there should be no noise at all coming from the speakers when the amplifier is turned on but no audio is playing. Stay tuned!

31/01/2026

At last, some good news!

The ground loop issue for the power amplifier has been resolved, and we are back in business!

This photo is about me enjoying the fruits of my labour. Today I got to sit down and actually use the amplifier for what it is designed for – listening to music! We are always chasing numbers and sometimes lose track of what it is all for. It is to have something where you can just sit down and enjoy.

This is the Hans Zimmer – Time (Inception – Live in Prague). This image is an Australian made amplifier and Australian made speakers! Let me tell you, this is a match made in Heaven as it is such an enjoyable experience.

03/01/2026

Happy New Year everyone!

I have been quiet and not had any updates as I only wanted to report back when I had positive news to share. Unfortunately, it is bittersweet news.

The good news is that the new custom made heatsinks, enclosure and electronics have been assembled. Everything fits and looks great! Please note: the pictures are just a prototype, and the cables still need to be tidied/polished up.

The bad news is – there is a ground loop
This is the biggest challenge people like me face with designing an audio amplifier. It is also a difficult task to identify the source. I have been tinkering for weeks trying to find the root cause of issue. Sadly, I am still banging my head into a wall with frustration - but I will keep on trying!

03/10/2025

Isaac doing the quality assurance inspection on the new enclosure!

Note I am still waiting for the new custom heatsinks to arrive, so I only have one at the moment.

30/09/2025

The first prototype panels are complete! It is a surreal feeling to have them physically here after all that time spent looking at them on the computer screen!

02/08/2025

Good news all around! I have found a local manufacturer to make the enclosure, and it is being built right now!

While that’s underway, I have finished the 12V trigger in/out PCB design.

Why would this amplifier need 12V trigger in and out?

1. It means equipment that has a 12V trigger out can turn on this amplifier. An example would be a network music streamer. Using your phone, you can turn on the streamer. The streamer will automatically turn on the amplifier through the 12V trigger interface. This means you can turn music on and off from your phone without having to go and physically turn on the equipment!

2. It can automatically turn on other equipment such as a subwoofer – saving you from having to turn on multiple devices.

This board has been a bit of a challenge since it handles mains voltage. However – I think this feature brings into the modern streaming setup!

29/04/2025

Here is render of the enclosure! It is pretty surreal looking back to where it all started. I started reading theory from electronics textbooks from the very beginning (I am talking Ohms law V=IR).

But now:
1. The electronic circuits have been simulated and designed,
2. The electronic circuits have been built and tested,
3. The amplifier as a while has been tested and sounds amazing, and
4. There is a render of how it could potentially look.

What a journey - I hope you all love the design!

Currently I am reaching out to suppliers to get this enclosure fabricated.

21/04/2025

I am so proud of the enclosure progress, and I just couldn’t resist posting a sneak preview of how it is coming along.

The concept behind the enclosure is:
1. It will have the chassis that will provide the strength and support the large heatsinks.
2. The heatsinks will be easily removable to allow for repairs on the power amplifier boards (these are mounted to the heatsink as shown in second image).
3. The enclosure will use plates and folded sheet for the outer skin. The outer skin will be mounted to the strong chassis. There are some features that I think you will all love but it took a lot of work in the design to make it work.

Please note that the image does not contain all the plates as I have to leave something for you all to look forward to!
I am just adding all the finishing touches and will be sending it out for quotes to bring it from a design in CAD and onto the bench space for some testing!

30/03/2025

There haven’t been any updates in some time as I have been busy:

1. Getting a new workstation computer for 3D CAD,

2. Getting a new 3D modelling package and learning how to use it to design the enclosure,

3. Spending lots of time on coming up with an enclosure idea.

The thing you may be wondering is how can it take so long to come up with an enclosure?

Established companies can use a variety of manufacturing techniques such as extrusion and machining to create any design they can draft up on the computer. However, as a small start-up, we don’t have as many options to choose from when it comes to manufacturing techniques. It limits it to folded sheet metal. This limits what geometry and profiles you can have for the panels, and you cannot just design anything in your CAD package.

It is not all bad news as you can have some amazing designs with folded sheet, but you just need to spend some time to consider:

1. Design for manufacturability – will it be possible for a local fabricator to make this enclosure. It is not just about making it as a one off. It is about being able to replicate each enclosure. This is about having consistency, so you don’t have fitment issues.

2. Design for assembly – will the enclosure be easy to assemble? To make a product affordable, it has to be simple and fast to assembly as excessive build time means higher costs to offset the labour.

3. Aesthetics – it has to look good. The goal of the amplifier is to have an enclosure that you would be proud to display. Having a great sounding amplifier is one thing, but you also want it to look nice in your home.

The initial enclosure concept is done and now I am working out the finer detailers in the internal frame. I reckon everyone will love it and be very pleased with the outcome once I get it made!

19/01/2025

This post is for those who just love numbers! I don’t mean that in a bad way as I personally am a numbers kind of guy.

Prototype 02 has been tested using the following equipment:
1. QuantAsylum QA403 audio analyser, and
2. QuantAsylum QA451 programmable 4/8 ohm load
I have provided a summary of the results and some screenshots from the audio analyser graphical user interface (GUI). I honestly couldn’t believe how good the results turned out to be. I actually wanted to cry from happiness. I will not compare them to other products on the market and go into detail – but you can see for yourselves how they compare to amplifiers on the market. I think you will also be quite impressed with what you find!

So, what next?
My favourite part – the enclosure design!!

Bartekh

09/04/2026

31/01/2026

03/01/2026

03/10/2025

30/09/2025

02/08/2025

29/04/2025

21/04/2025

30/03/2025

19/01/2025

Address

Website

Alerts

Shortcuts

Share

Category

Listing takedown request