21 Mar

The Dawn of a New Society – Blockchain & Artificial Intelligence

The dawn of a new society is upon us in the form of Blockchain and Artificial Intelligence. Here, I try to explain how these two technologies coupled together can impact society at the roots and enable both the public, businesses and the government to work effectively together to bring about significant benefits to society.



13 Feb

Volumio with Raspberry Pi as a music streamer

In my journey towards home automation and more recently the topic of wireless audio, I have researched, experimented and built some kits around first using the google Chromecast audio and now the Raspberry Pi.


The Raspberry Pi setup was fairly challenging and naturally being open-source required some level of understanding how how the innards worked. Chromecast audio was a sinch to setup since all it required was the Chromecast audio itself, along with 12V, 5V power supplies and of course a power amplifier all supplying a speaker. It was a fun project and something I will post at a future project.


For the Raspberry PI, I wanted to have the same setup as the Chromecast but needed a few items to accomplish this.

Raspberry Pi (I had the Pi 3, Model B)

Hifiberry DAC+

SD Card to mount Volumio (Music Streaming Platform server)


I initially experimented with RuneAudio which immediately took me to a screen where my mouse would not work. I used the keyboard (Alt tab) to select the items needed to set it up and could not get the wireless to be setup as I did not have an ethernet connection. The RuneAudio server did pick up the wireless connections but I could not save the WLAN setting. Although later on I found how to setup the WLAN in the network/interfaces setting which I may try again down the line.


Having played with Raspberry Pi now for a week, I can see how some people can become extremely frustrated with the lack of documentation and help. You literally have to wade through many forums and type the right questions into google to get to your solution. Luckily for me I was versed with some command line usage in the Linux environment so knew how to get around even if no help is around. To make the matter worse the ‘open-source’ community of software development have a ‘nerd-like’ feel which pretty much rules out many novices in experimenting with things. Although the Arduino community seems to be striving really well with a strong base of users and community support. I have yet to dabble in this space, but keen to venture into it as I have many IoT projects in mind including home automation.


Getting back on the subject of Volumio, my first step was to download the Raspberry Pi build from their website…




I followed the instructions for creating the image and writing to the SD card on my laptop and then plugging into the Pi. I used the hotspot of ‘Volumio’ that appeared against all other wireless networks and selected that in order to setup the actual wireless connection through ssh. Once in ssh, I setup the wireless connection according to the page instructed here…




I then rebooted the Pi and switched to the network that I was using and then pulled up the volumio.local on my laptop which appeared to show a page. I also added the actual IP address to make sure I was on the right page. The bloody thing kept hanging with the familiar icon spinning with the faint background of the actual page sitting pretty at the back. I researched google to find out the issue and found several topics that related to this issue. One resolution was that it would work only for Mac or Linux, so I switched to a Linux machine and tried but to no avail. Apparently, it seemed that many people were having this issue and Volumio folks were not being very helpful and hence the reason for this post.


By the way, I already pre-tested the Hifiberry on the Pi by manually setting up a mpd as provided by the instructions here…




I was surprised with little time I got the hifiberry to play a sound. Unfortunately, the sound was deafening as I had fed this directly into my amplifier input which has no gain control (it’s just a small amp module). I researched on how to control the volume and some suggestions were using alsa mixer whereas others were referring to hifiberry hardware control. The findings were all sketchy and did not give me a clear solution on how to achieve this and so I decided to go for a pre-made media server like Volumio.


Having tried all sorts of things in trying to get the Volumio work, I had an epiphany.. which was to use a previous version of the Volumio. You won’t be surprised to learn that even finding a previous version was difficult. Why on earth would the volumio site not put up previous versions of their software? They are doing a terrible injustice to the people (and also their product) who are diligently trying out their software but failing all because they cannot be bothered to update their website. Anyways, I have learnt (now) that when you are dealing with open-source software, your best origin of information is not the cnet.download or sourceforge but the github repository where all the development is going on. I managed to track down a previous version that I know would work since I saw the whole process being shown on a youtube video. The image version I obtained was the following…




Whereas the version (latest) shown below DID NOT work for me and I suspect many other folks who are using the Raspberry PI 3, Model B.




Naturally, one should try as much to rule out issues related to installation such as a bad copy, potentially firmware issue etc. The fact that a previous version worked without issues suggest there is something wrong with this new version and Volumio should address it ASAP.


Anyways, I hope you find some solace and peace that the issue with the latest Volumio build for the Raspberry Pi may not be necessarily your fault.


My next tasks are to setup the Volumio player and maybe decipher what is going wrong with the latest version. In addition, I want to test out the hifiberry DAC+ to see how well this sounds. Stay tuned for more upcoming posts on this subject!

Volumio with Raspberry Pi

Volumio install for Raspberry Pi


5 Feb

Compare In-Wall Speakers – Micca, 652W, VM Audio

Recently, I got very interested in building speakers and as a result, I google my way around everything there is to know about speaker building. I was intrigued to find that there were many people who are also passionate about this subject and there is a whole science and art behind it. Being a technologists and avid maker of things, I was comfortable in picking up some of this knowledge and turning it into a project.


As with all creative projects, it requires money, dexterity, knowledge gathering & application, and a great deal of perseverance as well as patience. I understand that not everyone are inclined to work and think this way but they do care about what they buy and hence this article. It is directed towards folks who are looking for the best in-wall speakers but are not able to make the decisions as they don’t have any information regarding it’s sonic performance against other comparative products.


The tests in this post compares three top-selling in-wall speakers that can be found in Amazon. Unfortunately, there are no side by side comparison of these products in terms of sonic performance for users to make a productive decision regarding cost vs sound quality. In this post, I summarize a test rig that I prepared that will hopefully help you in arriving at this decision.


Under the tests were the 3 units shown below which appear to be to top sellers on Amazon and have received favorable ratings.


 Micca M-6S 6.5 Inch 2-Way In-Wall Speaker (referred to as ‘Micca’)



652W Silver Ticket 2-Way In-Wall Speaker (referred to as ‘652W’)



VM AUDIO Shaker 6.5 2-Way In-Wall Speaker (referred to as ‘VM Audio’)




The test lab for comparing the speakers

Like all good experiments, it is important to have an experimental bed that will be constant for all test conditions for the speakers. Effectively an environment that can be kept constant whilst feeding the same audio source and determining the sound profile. Note that I have not used any measuring equipment to do this comparison and might spark debates from audiophiles. However, the end goal was simply to measure the sound from the speakers for the same consistent input and determining it’s quality against each other. It can be said that everyone has a preference towards a particular taste in music but that would not detract from the fact that you are judging the same music coming out of each of those speakers. As long as my feet are on the ground and not dancing vigorously to the music, I felt the tests were going to be an objective one.


were simply my ears with everything else being constant including the passage of sound to my ears and all furniture as is.


The test rig…

For the test rig, I made a rigid plywood box with an open front that will comfortably sit the speakers flat and taped with duck-tape to minimize sound leakage. This set-up was fine since the requirement for a tightly sealed box or sound deadening material were not an issue as the speakers were subjected to the same conditions under listening tests. The speakers connected to the in-house amplifier, chromecast audio and power supplies (Fig. 1).


I was already somewhat familiar with the VM Audio speaker whilst building out the amp rig and had a general feeling of what this sounded like. I plugged the Micca speaker as I was anxious to hear this speaker considering all the rave reviews received in Amazon. I was immediately awestruck by its sound, and all the music I pushed through it on my Android tablet (google music player) sounded pretty good.


However, the speakers were stored in a cold room (NYs inclemental weather) and so I knew they needed to be warmed up for a good test. Some folks also recommend a break-in period of 2-3 days of continuous music before you can fully appreciate the sound. However, you can argue that all three speakers under test were subjected to the same temperatures and break-in period and a direct measurement one after another would not skew the tests. One could also argue that the materials used may have very different properties to each other requiring different levels of break-in before they are fully ‘cured’. I won’t into the details of this so I thought it would be best to let the speakers sit in room temperature for a few days and conduct a protracted listening tests for all three speakers.


For the tests, it is important to make sure that speaker placements are exactly the same ie. position on table, from the wall and any other objects nearby. It was important that I was also listening from exactly the same position of where I was sitting. I was also aware of the fact that resting hands behind your heads would compromise the tests. If you don’t believe me, place your hands facing forwards behind your ear and you will see how different all the sounds appear. Such were the lengths I was prepared to go to in order to pick out the various nuances of sound emanating from the speakers. In case you were thinking, I was not exactly a sitting robot 🙂 It was the only way towards appreciating and optimizing a product as I have further audio projects in mind for my new found passion.



After subjecting all three to protracted listening tests I have provided the following results for the readers. Keep in mind that the applications for these speakers are for in-wall application and subjective tests such as this only qualifies its rendering capability of sound. It would be hard to say how the speakers will sound on your wall and according to the room size and your furniture placement. Equally, the type of amplifier you choose, will all add up to give the final overall sound that will come out of these speakers. Sound engineers call the in-wall environment as an infinite baffle whereas the closed-box tests is how I am conducting these sound tests. It is safe to say, the quality of the listening tests are arguably the same for each speaker and any deficiency in particular frequencies, distortions of the sound would be a faithful measure of the ability of the speaker to render sound.


Initial testing…



Warm sounding, less distortion (well matched to this amplifier).

Whitney Houston, OTOWAA voice, dialog

  Some timbre distortion evidence when changes gear, otherwise voice clear, good mid range and appears to have more bass than VM


 lower sensitivity (but that is ok, the 60W more than capable at listening to high volumes)

need to show the loudness at mid-point of the chromecast


$25 625

 Treble (bit grainy (harsh) and high), whereas Micca sounds like together

 However, broke in is about half hour whereas Micca broke in 1 hr

 Micca warmer and more enjoyable to listen, feels like you could listen to this for a long time without being fatigued

Sharpness in the higher frequency that is noticeable

VM $10

Surprising good, does not have the deficiency of the mid priced one


I was quite surprised by the results of these tests as the addage, ‘you pay for what you get’ would naturally apply but not so for these batch of speakers. The V652 has a harsh treble that you just could not discount from all the listening tests. The Micca sounded more warm across the frequency range and was enjoyable to listen to as it depicted no harshness like the V652 and also had a good soundstage. I was most struck by the performance of the VM Audio which for the price point has to be a bargain for what it delivers. It holds itself up against the Micca very well and has a muscular quality to the sound. Although not as warm sounding as the Micca, it did not have any harsh qualities throughout the frequency band.



After subjecting the speakers to a break-in and listening to the same music repeatedly through each speaker, I was able to reach the following conclusions.


Sound Quality:

 Micca, VM, $25



 $25, VM, Micca


Overall (value for money):

 VM, Micca, $25


Your money will go a long way with the VM but if you are really picky about sound and like a more restrained (or mellow) listening experience then you can opt for the Micca.

Bear in mind that this speaker is almost 4 times as much as the VM speaker and as everyone says, sound is a subjective quality.


Further work:

I hope that this post benefits some of the readers in deciding what in-wall speakers to choose since ratings are not always the most accurate measure of picking out the right ones. My next tasks will be to see how these speakers sound like with the proper optimization of other parameters such as sound box dimensions, rigidity of box, fibre materials, amplifier matching etc. Like I said the acid test would be to hook these up to your own walls and see how they sound but based on these tests you can get an idea of the quality of the sound that each produce.


25 Aug

Why are bluetooth devices so awkward to use?

I am not sure if I speak for many of the readers when I say that I have had hit or misses when it comes to pairing bluetooth devices.


bluetooth devices from china

Bluetooth devices can be a bugger to get working


Bluetooth has been around for a fairly long time and it was back in 2004 that I actually purchased one of the miniature headset that are in large supply today. So the other day, I decided to purchase one of these cheap headsets for literally under $5 from ebay. The first one I ordered was a tiny unit that simply sits inside your ear and of course it has a tendency to fall off.


I was able to pair this device to my Samsung Galaxy Note 4 fairly easily and it wasn’t too long I was listening to some youtube channels through the headset. However, the sound from the thing was very faint so I thought it would be a useful device that I can keep in my ear and listen in the background whilst I do work. However, since the device had a tendency to fall out of my ear, I thought I would check another one out that could stay in my ear. I forked out another one for just a shade under $5 and this one had a hook that wraps around the earlobe and stop it from falling.


I was very surprised that the second unit that had supposedly come all the way from China took just 7 days to arrive. I was creating all kinds of scenarios in my head as to how they did that ie. passenger planes – throw it in with the other bags, freight planes etc. Still I was dumbfounded as to how they can possibly offer free shipping with the unit priced under $5. This would be almost unheard of if you go back 20 years and probably told never in a million years.


I still have to figure out how you can ship one item with next to nothing all the way from China. However, I do have a hunch that there is one operator who takes shipments from all the distributors and puts them into a larger shipment and is able to offer the cost savings to the distributors. Anyways, I am sold in buying from China and I already have a few more items coming from there. After all, Apple has its stuff made in China and so far I have been happy with the smaller items from China and ready to order some higher purchase items. Call me a traitor but it beats the prices you get here in the US.


So going back to the subject of bluetooth devices, I found that keyboards are even more difficult to pair. Apple surprisingly does makes very easy task of this affair with couplings of the mouse and keyboard, but maybe it doesn’t use bluetooth, I would need to check. As I am exploring the bluetooth devices ie. configuring, uninstalling, reinstalling, pairing and unpairing, I expect to have useful information for my readers on upcoming posts.


Stay tuned for more!