Saturday 28 May 2016

Analogue vs. Digital Audio

I've just read this: An interesting fairly well balanced view of Analogue vs. Digital reproduction of music.

I am not what I would call an audiophile, but I do appreciate the "quality" perceived or imagined of music. The emotional quality and as the Techrepublic article puts it the emotional response to placing the needle of the turntable on my beloved vinyl recording.

However to add my little bit to the debate, it has come to my attention that dynamic range seems to be the thing that has taken the beating. I even did my own experimentation with this and pulled an MP3 recording that seemed washed out and very difficult for the singer's vocals to be heard.

I pulled a dynamic range app (TT Dynamic Range Meter) from the Internet and also ended up here: It seems I am not alone in spotting that the music industry has been making music louder at the expense of what I feel is "quality". You need to hear the tinkle of the symbol and the bass of the drum and the full range of frequencies and loudness levels to get the "texture" of the sound.

You also (IMHO) need to have something decent to provide the reproduction of the source material, LP, MP3, tape, CD. I have to admit to having a very old circa early 80s Sony separates system, which still has its original Amp, Deck and an addition of a circa 1993 CD player.  Playing various sources, new and old Vinyl and new and old CDs, and MP3 via the AUX input from my phone, I can hear the difference between older reproductions where the dynamic range is wider.

That also takes me on to a recent discovery, not a complete revelation for some I am sure, but new and surprising to me. I recently tested a soundbar - Thank You Richer Sound for the week trial. I get fed-up with not being able to hear the dialogue from movies.

I have a very nice Logitec Z5500 surround system. Which I plug into my blueray/DVD player and we have a family movie night using a projector on the wall. The dialogue is loud and proud using this set-up and full on 5.1 THX certified sound a pleasure to listen to....... So with this as my baseline, I figured that the less than perfect speakers in my flat panel LG TV could be improved on with a soundbar. Now I didn't go top of the range, or the bottom - I thought lets shoot for the mid-range and one that has won a What-HiFi award.

Let's just say I was disappointed. Where was that Centre Dialogue - still not there!!! even using the Direct Digital input from the HDMI cable. So the soundbar went back to the store.

Last weekend we did a movie night but, not on the projector and DVD, but streamed from Amazon. I plugged my Z5500 into the Optical out of the TV and "WHAT!" where's the 5.1 audio gone? It seems the compressed audio format for streaming media required my Z5500 to be manually switched to decode in Dolby Prologic II. SOOO that explains a little of why unless you go with a soundbar with all the bells, you're still gonna get poor dialogue. Also to my surprise whilst looking at soundbars, there nearly all 2.1 - unless you pay a lot more and then well quite frankly - save your money and stick with a proper decoder like my old Z5500, half or a third of the price of a top notch sound bar and SOOO MUCH more sound for the money.

Thursday 30 July 2015

Dell Studio Windows 8.1 to Windows 10 (Free upgrade)

So did the Windows 10 upgrade - OK first impressions looks like what I know, but wait a minute - Dang my Bluetooth mouse isn't working...???

OK no Bluetooth in control panel... RUBBISH - deleted the drivers I only just put up there from Lenovo - so re-install... YEAH! Bluetooth back...

Hmm ATI Radeon drive - MS own flavour doesn't have the right mode to drive my LG monitor (1080p) via VGA connection... Hmm more work to do here....

Re-installed these "old" drivers and rebooted, fingers crossed... Nope No luck - looks like I'm stuck with my Windows 10 default drivers - work fine on the inbuilt panel - 1920x1200 - so will have to do for now... Hmm HDMI port - might be a better choice - but gonna have to get the soldering iron out - this is not the most robust connection and mine is loose from repeated use.

Saturday 25 July 2015

Dell Studio 17 Windows 8.1 Broadcom Bluetooth solution

This post is as much for my own sanity as the community at large. Having taken the step back to Windows from my Mint desktop on my Dell, the Bluetooth driver from Dell failed badly and Windows 8,1 Pro flatly refused to detect my Dell 370 Wireless card.

Then I found:

Which led me to:

Downloaded and installed the Lenovo Driver and all working just great - Bluetooth Mouse and Keyboard connected and writing this article with them!!!

Come on Dell!!! Easy fix if Lenovo could do it!

Friday 10 October 2014

Part 2: SIP Based Call Centres - 12 years on - Time for a light weight cloud approach to contact centre architectures

So what does a cloud architected contact centre look like? I guess looking at from an architectural requirements:

  • No Single Point of failure
  • NoSQL Database for "Big Data" based Agent and caller statistics (not mandatory but useful)
  • Scalable transaction engine for orchestration of resources - linking customers with agents and agents and supervisors (We used to call this a queue and scheduler - or just the ACD)
  • Media Relay/Anchoring so that recording of the session can take place.
  • Light weight client applications (HTML5, CSS, Javascript, WebRTC).
  • Elasticity on demand compute - to scale for more sessions, more agents etc. Or for that matter less.
  • Some form of orchestration to be able to dynamically scale the platform based on either dynamic demand or customer requirements. Dynamic demand is an interesting one here as it implies the platform can "self-scale".
  • Multi-tenancy, so we can accommodate multiple customers without them "bleeding" into each other.
  • Support for SIP Signalling (to be able to connect to telcos using SIP trunking)
  • Transcoding of codecs voice (& video).
  • Conference bridge/RTP mixer, to make supervisor passive monitoring of agents  possible.
So that's the high level requirements out of the way.  How might you lego-brick build such an idea as a prototype? I'd start with Freeswitch and Kamailio/OpenSIPS, and I think I might even look at commercial SIP to WebRTC gateway like Genband's SPIDR.

For the Virtualisation piece I guess I would start with OpenStack and/or Xen hypervisors.

That's my shopping list. Next time some pictures of the components and glue-ing them together.

Online homework and social media pose parental dilemma - What!

Is it just me or do articles like this, on the BBC website make you annoyed too?

** Parents face online homework dilemma **
Parents feel unable to make children study by blocking internet access, as homework often requires online research, a survey suggests.

The problem here (IMHO) is education - not the children you understand, but the parents, there are so many ways to protect and inform children about the Internet, and most of them are free.

The best free tool around I have found is OpenDNS, this give parent control of not only every device in the house, but also allows you to protect friends children too who Bring Their Own Devices.

Windows and iOS have darn good parental controls too, its just about setting them up and discussing it with your children. - Even Google and YouTube - if you create an account can be set with parental controls too.

There are no excuses... BUT - we need to educate the parents.....

Wednesday 9 October 2013

SIP Based Call Centres - 12 years on - Time for a light weight cloud approach to contact centre architectures

Back in 2001 - Wow that seems a long time ago now that I sit here in Oct 2013, I wrote a white paper which was published back then by the International Engineering Consortium in their Annual Review of Communications, called SIP Based Call Centres - A vendor independent architecture for multimedia contact centres and thanks to the Internet can still be found out there.

In the paper I sang the virtues of open standards and SIP for building contact centres capable of meeting the needs of a modern multimedia environment (voice, video and Instant messaging and presence). Since then (IMHO) SIP has become quite frankly bloated by extension after extension, and one SIP doesn't necessary work with another SIP, so SBC now have to mediate between different flavours.

I think its time to revisit signalling and communications in modern contact centre, after all the point is to let customers reach someone who can help them in whatever way best suites the customers need, in an efficient no frills way.

On reflecting on what I wrote 12 years ago and the current surge of interests in WebRTC and all things HTML and cloud, it struck me. Now is the time to rethink the way we build multimedia contact centres both for the customer and the business that uses them. Actually it wasn't too new a thought - I'd already put some top level architecture ideas together about a year ago when looking at a new approach to telecare with some colleagues over at Inmezzo. The approach for the next generation of contact centres means a much lighter footprint - no complex clients to use for the agents, no nasty plugins in the browser for customer, integration with the PSTN, voice, video and text chat from desktop or smart phone.

What doesn't change is the basic requirements for session queueing and routing, or the ability to present information about the contact.

So what does this new architecture look like.... Well I'll leave my thoughts on that for the next blog entry.

Monday 7 October 2013

We are entering a new era of software defined communications

What now feels like a life time ago back in the dim and distant past ,OK - not so dim and distant 1980s, I was a young apprentice engineer with my training and interests firmly focused on Hardware (micro electronics more specifically). In 1987 I made the bold step towards software engineering as a choice, since it seemed, back then, that software was the way forwards to creativity and new solutions for communications. Having "converted" to software engineering by way of a degree in Computer Science at Aberystwyth University, I then continued in that vain becoming a professional software engineer. I still didn't forget the electronics that got me started, and this combined with software engineering put this to good use as a telecommunications engineer. Moving through the heady days of Nortel Passport Frame Relay Switches, Cisco AGS and MGS routers and Cabletron hubs.

Then the Internet happened.......

For the telecoms engineers out there (like me), in my humble opinion (IMHO) SDN is the networking equivalent of softswitches? The OpenFlow API is what MEGACO/SIGTRAN is to soft-switching and the so-called Orchestration layer the Stored Program Control Logic from the switch fabric and routing fabric. The media gateway is the Hardware forwarding platform (L2 switch fabric being physical of logical vSwitch, Microsoft Network Virtualisation and Virtual Subnet Identifiers), not to mention MPLS enabled VPLS and the rest of the MPLS "family".

And now in the telecoms field we're getting all excited about Network Function Virtualisation (NFV - . This is really about extending the Virtualisation platforms/techniques like those provided by VMWare ESX and Microsoft HyperV into the telecoms space and placing the Functional elements of the NGN network on these virtualisation platforms. As the ETSI White paper states:

"leveraging standard IT virtualization technology to consolidate many network equipment types onto industry standard, high-volume servers, switches and storage."

This allows the economies of scale that the enterprise networks are gaining through "cloud compute" to the telco space, by implementing these traditionally custom hardware based elements (such as media gateways, firewalls, SBCs, Routers, CSCFs) in standard (commodity Servers) architecture servers and a hypervisor layer, utilising the same virtualisation tools which enable flexibility of deployment of these elements in more standard environment, enabling features such as live migration of network functions under failure, multiple instances of a network function on the same hardware elements, and more interestingly (from my perspective) the ability to create multiple instances belonging to different customers (or even carriers) on the same hardware platforms.

Time to re-write the architecture rule book.