Aug 132016

There do seem to be folk who actually read this / stumble across the blog perhaps through searching for random tech stuff in spite of me rarely promoting it I thought I’d post an update and what I hope to do with this space..

Unfortunately last year I had to deal with a family bereavement as well as health problems/tiredness/burnout; often after I have finished with work-related tasks (which I try and prioritise my energy towards as I am lucky to have a very understanding and accomodating employer) I am way too tired for much else, such as music/creative stuff such as photography and tech/electronic projects.

Also slowly realising I am getting older and have had to make some different lifestyle choices; much less partying and late nights compared to my nearly two decades as a raver, DJ, party promoter etc. All good fun but starting to get a bit much in the end.

This has slightly reduced my enthusiasm for “harder” electronic music, so I have temporarily removed the online radiostation VFR Europe from here (as I hadn’t got the time to curate, upload and schedule content, let alone work on my home studio) although it will hopefully return in the future.

For those who want music there is still plenty on

The good news is I am slowly regaining energy as well as getting into a better routine of sleep patterns, eating etc than in my “youth” (I still don’t consider myself to be old!) and there are still things I get up to I can blog about so hope to be posting here more often.

I don’t do “social networks” much – I (re)tweet occasionally at @vfrmedia (when I get round to it will add the twitter sidebar) and have no desire to become a “social media star” so this blog isn’t going to contain the latest “hip” technology; but will reflect my diverse tech/engineering interests (including “retro” stuff such as my reignited interest in fountain pens) as well as nature/and environment related content….

Jun 282015

Finally got some time to test these loudspeakers, albeit in a different location to where I ultimately plan to deploy them in EPC1 (my studio and workshop).

Tannoy Mercury V1i loudspeakers / luidsprekers / Lautsprechers / enceintes

What they look like from the front; standard rectangular box shape (unlike the Wharfedales which are curved and bulkier)

Tannoy Mercury V1i loudspeakers / luidsprekers / Lautsprechers / enceintes*

he rear binding-posts – complete with clear plastic covers on them (some type of EU safety rule?). Unlike the Wharfedales they do not have the bi-amping links, fine by me as I don’t use two amps – these are my house systems; not a rave rig 😉

Tannoy Mercury V1i loudspeakers / luidsprekers / Lautsprechers / enceintes

What they look like with the front covers off.

As I am still tidying up EPC1 (my workshop and studio) I tested them in my bedroom, in roughly the same position the Wharfedale Diamonds are situated.

I connected them to my Sony AV receiver (made in Malaysia in 2009 – more an “Aiwa” in a less brash case.

It has a traditional 1980s era design with a linear PSU and 100W RMS output per channel

I used the output of my laptop and a Raspberry PI B connected to a cheap C-media USB soundcard (better than the internal soundcard which is noisy and a bit “flat” sounding).

This room is smaller, my previous experience of Tannoy LS units (there are some at ICR-FM studios used as studio monitors) is that they need room; otherwise they sound “muddy!”  The good news is these ones do not suffer from this flaw – I tested them with everything from German Christian folk music and speech content from Radio Maria Nederland to 80s synthpop and hard techno!

it did seem I had to “give the amp some gas” compared to the Wharfedale Diamonds to get the same sound level (even though the sensitivity of these LS units are supposedly the same) – I haven’t done any “proper scientific” tests but I think the Wharfedales are heavier on the bass than the Tannoys. – but when the tannoys were given the right power they were strong and clear; sounded perfect for radio production. they may not be pro monitors like the reveal but to my ears they aren’t too far off

The Tannoys are way more directional and need to be positioned well – this could be an advantage in EPC1 as it will reduce noise nuisance to outside. So everything works out just right as I intend to use the Wharfedales for general listening [as an upgrade to “Japan” midi system (again made in Malaysia!) and the Tannoys as monitors for DJ mixing and studio production.

Jan 272015

I want some bright lights to flash in the studio when the VFR extension rings (rather than bells sound). The analogue telephone circuit uses a ringing signal of 80-90V AC at 25 Hz (it is quite strong; if you accidentally hold on to bare telephone wires it can definitely be felt!) – and all sorts of random signals can come down a phone line.

So I had to build a circuit to isolate the phone line from any other equipment; not let through any DC electricity (or the phone line will be permanently engaged) and reduce the voltage from the line to trigger an optoisolator.

first video is internal PABX call

second is external call

the circuit is here – the zeners are 10V and capacitor (to block DC and not seize the phone line) 470nF.

The PNP transistor switch is used as the opto is connecting to ground – the 10K resistor which also acts as a check for the opto output (as those 6 LEDs will eventually be in another unit elsewhere) also is a pull-up resistor for the transistor switch. The LED LD1 still glows very dimly even when the circuit isn’t active; maybe I should remove the 220K resistor (that was recommended in the original transistor switch design) as there is actually only 18k resistance between the 12V supply and the “active” LED and possibly leakage current gets through.

That said TBH it works and provides the signals I want so I may leave it at that…


telephone ringing detector + LED driver cct

Nov 302014

short update – had to swap the positions of the Soundtech Series A console and my electronics maintenance workbench – stil loads more to do but here are a few pics

displays by night timeEPC1 by night


DSCF1341Studio clock / monitor signals from Raspberry PI (which can also be used for stream monitoring/silence detection) connected to the cheaper of the two HDMI TV sets (and old one my mum brought with her) that doesn’t have as much resolution [she got the slightly larger and better picture quality LG set that was previously in this position, as she actually watches TV 😉 )

I had to deal with altering /boot/config.txt and all sorts of other settings to get a half decent picture on it; its just about good enough for a clock..

output of soundprocessing