RIAA Preamplifiers on a Budget

Pre-amp Circuits for turntable MM or MC reproduction

Apologies for the lack of updates over the last few weeks, our scribe has been off ill for a few weeks. Here’s to a new session of articles and hopefully a little bit of invigoration to our framework.

The true value of Vinyl

It’s amazing how times change – I was recently given a treasure chest of CDs, DVDs and records (vinyl) from my brother whom has left our shores for the UK and guess which media carries the most value?

In line with this and the comparative interest from local folk to listen to vinyl (read: huge interest) we thought it relevant to add some words on the subject. Continue reading “RIAA Preamplifiers on a Budget”

Parts for Vintage Equipment

Where to get vintage gear spares?

Over the last 6 months I have received quite a few mails from desperate individuals wishing to restore their old radios, tube and semiconductor, integrated amplifiers, turntables and tape decks.

Honest Sam's Top Notch Sales - Cars in Unbelievable Condition
Honest Sam’s Top Notch Sales – Cars in Unbelievable Condition

Belts and power supplies and many semiconductors have equivalents but we get stuck with Germanium, decals, knobs and switches with most gear and then the mechanical parts to decks and turntables. In South Africa we have to turn to eBay where often shipping charges become exorbitant. Continue reading “Parts for Vintage Equipment”

Ampacity and Current Handling of Conductors

Live shows, domestic and industrial power – it’s all about Ampacity

Report: 2013:- South Africa has approximately 60 000–80 000 unnatural deaths per year, with an average of approximately 70 000 per year. There are currently 36 registered forensic pathologists in South Africa. An electrocution death is considered an unnatural death and is, therefore, referred for autopsy
examination in South Africa. Continue reading “Ampacity and Current Handling of Conductors”

What’s in a Vocoder – voice synthesisers and Robots

Kraftwerk, Styx and My Vocoder – Shaping human voices

Generating and shaping audio and RF wave patterns has long been an interest for many and is seen in the medical, military and commercial industries.

Not wanting to re-invent the wheel but rather looking at another spin, what is the appeal?

Although there are many makes and models, dedicated or otherwise two entry level but well rated models are the Roland VT-3 and the Paia Vocoder designed by Craig Anderton. Check out an upcoming series as we attempt to build our own.

An off-tuned SSB received signal through the BFO will create vocals which sound like monkey chatter or off pitch. It doesn’t take radio students long to see the multiple effects ring modulators and different tones have on the output.

Circuits and Kits

Instructables – Build and Analog Vocoder by Planetone

MFOS – Music from Outer Space / Article / Makezine

Ghetto Talk Box

Muffwiggler / Elektor 10 channel vocoder

And of course….

Crank That Soulja Boy Talk Box (from Ghetto Talk Box)

Audio Tools

Two of my favourite audio tools would be Audacity (free) -multitrack recording which allows effects and of course, Reaper, a fully equipped DAW.  Free for 60 days then although not crippled, $60.00. You will not find this kind of software anywhere for this price.

Both the above allows vocoder inserts and with proper manipulation are exceptionally good.


Further Reading

How Vocoders work – Craig Anderton (Paia)

Patch Bays or Mixers

Patch Bays and Mixers, sometimes the obvious isn’t so obvious.

There are lots of posts on the forums where users are either attempting to build their own patch bay or trying to switch a mic signal through a patch bay. The general feel is never to switch phantom power through a patch bay.

Allen and Heath Xone DB4
Allen and Heath Xone DB4

A studio mixer with sliders all facing the horizontal axis is often one of the best solutions as long as the mixer as enough line outs to feed a patch bay. What happens if you have a rack mounted console with combo receptacles (XLR/TRS) at the rear of the unit?   Continue reading “Patch Bays or Mixers”

RCF Near Fields – Ayra Series

RCF Active Near Field studio monitors – the Ayra series

RCF have been around for some time, almost 70 years to be exact. Named after the initials of the first three shareholders (but also formerly known as Radio Cine Forniture?), the company invested in the manufacture of ribbon microphones. With concerts becoming more electronically amplified RCF soon turned their art to the manufacture of transducers and the release of OEM devices for loudspeaker manufacturers in the USA and Europe.

RCF Ayra 8 - Active Near Field Monitors
RCF Ayra 8 – Active Near Field Monitors

When one does feel the urge to find out more about this company and their products the internet is strangely quiet. My first experience was actually in trying to get my hands on a pair of Yamaha or Behringer Truth monitors but the sales person motivated the sale of the Ayra 8s.  Pressed for time and knowing nothing about RCF except their use in large stage arrays I only did research after I laid out the cash.  Look, in all honesty the audio industry is amok with clueless critics tearing apart well known brands without thinking of the consequences (forum trolls, trap bait and undeserved criticism) – but I hardly see RCF comment.  Continue reading “RCF Near Fields – Ayra Series”

Focusrite 18i20 Revision One

Focusrite 18i20 Release One

As an avid user and lover of the Focusrite mic preamps I recently found my preamp had a broken button for the +48V phantom supply.  As one part of the button had broken off I tried to find the missing part and try a quick fix. Since I had to open the unit I’ll share some thoughts.

The 18i20 uses Cirrus Logic CS4272 114 dB, 24-Bit, 192 kHz Stereo Codec A/D DACs, JRC4565 (New Japanese Radio Company) and HEF4053 triple single pole double throw analogue switches.

Although I paid way over market RRP for the unit they were in scarce local supply when ordered so I wasn’t too surprised. As a DAC it’s absolutely incredible and although giving spec lower than some of the others giving a more optimistic SNR there is absolutely no audible noise.  I use Eltax Millenium 500 speakers in the sound system as the main drivers along with some cheap arsed Sansui’s and although the Eltax speakers are supposedly entry level and bass heavy I have not found this to be the case. As a rule this website is not critical of other products, we aren’t a Phile Critics Zine Zone, the Eltax 500s perform very well on higher powered amplifiers. I also use RCF Ayra 8 monitors for mixing.  The Focusrite – Behringer NU6000 mix makes for good listening and although the Golden Eared fraternity may cringe I think the match is pretty good. The Eltax btw handle an input power of about 400W admirably with absolutely no audible distortion.


The first revision 18i20 may not have the newer GUI of the newer version, neither the latency but it doesn’t really make a difference in the grand scheme of things. But you should be able to pick up the older version now quite cheaply which makes it a very attractive purchase. I have read a lot about out of box failures etc but if you are on the lookout for an 8 input mixer I cannot think of one thing which is against the Focusrite.  Oh, I wish they had used alloy knobs and buttons, plastic doesn’t do this product justice. Let ist cost more, this is a beautiful product.

Focusrite 18i20 1st Edition top cover removed
Focusrite 18i20 1st Edition top cover removed

As far as DACs go, I cannot fault the unit. I don’t particularly like the mixing software, more to get the hang of  the I/O but it’s not a difficult learning curve. I believe Numero Dos (and no, not the “gonna have a number two” kind) has what I would term more efficient software, shorter and more understandable mixing software.

If you are planning to purchase a digital mixer in the near future to do recording/mixing through USB, give it a try. All of the models are similar except of course for the amount of available channels.

More info coming up in a future column.

The MicroKorg and other Best Selling Synth

Korg M1 - By Deepsonic, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=66234414

Best selling synthesisers of all time

Just in case you may have the MicroKorg don’t be too surprised to know that it may just be one of the best selling synthesisers of all time.  Without having the data from any manufacturer readers may not be entirely convinced but considering that they have been manufactured since 2002 reflects the popularity of this model series.

The pure versatility that digital or DSP driven synths brought to the market ensured a very quick surge in sales especially in the home and garage band amateur and pro space. Having purchased a CZ1000 in the mid 80s whilst in Yokohama it became more a showpiece until a musician friend showed me the full potential. Sadly it was stolen about two years later, possibly as a result of its popularity. 😈  Continue reading “The MicroKorg and other Best Selling Synth”

Why Behringer?

Behringer X32

Why do we promote Behringer as a brand?

Shane in Kenwyn sent a mail to us about three weeks ago asking why we tend to promote Behringer as a brand?  The quick and nasty reply would be yes we do, no we don’t. Actually we don’t have any bias towards any manufacturer but we do stick up for brands that may be getting an unfair reputation.  We need to look at the trend towards Asian manufacture and then our own demographics.

Behinger EP4000
Behinger EP4000 2 x 1kW into 4 Ohms

Over the last 20 years or more China has become the hotspot for European, Japanese and American manufacture of electronic products and for the sake of this article we concentrate on professional and consumer audio gear, laptops and computer monitors.  Through early years there has been countless reports of manufacturers battling with quality control and R&D, more often than not still in the country of design.  This has changed tremendously.  We mustn’t kid ourselves, both Taiwan and the ROC have moved up the ladder to a deserved #1 spot in many fields.  Recognised as copycatters, this role may well be reversing.  Chinese engineers are some of the best and highest paid in the world, so much so that manufacture is looking at Indian manufacture to remain competitive. Continue reading “Why Behringer?”

More about DACs – the A/D Converter

M-Audio Fast Track Duo

The A/D Converter – pushing vinyl to digital

The common and garden DAC can be picked up cheaply at most electronic stores, ready to run straight from your CD player through optical (Toslink) or coax and used to drive your analogue only system.

Although these little units are cheap by comparison to high end products being portable they can be used in most cases where a device does not have an analogue output so you really don’t have to trash your vintage equipment.

Going higher end there are literally hundreds of different brands to choose from, most having bidirectional data lines through USB which allows one to input binary and output analogue or vice versa through ADAT (Toslink) usually.

Behringer U-Phoria UMC20
Behringer U-Phoria UMC20 – Audio Mart and Sound Select

For anyone wishing to record vinyl to their computer one would need a RIAA spec preamplifier. For tape or cassette deck the line outputs would suffice but in most cases non-professional decks would need further amplification. Why? Continue reading “More about DACs – the A/D Converter”