Tantek Tanrak

Tantek's Tanrak system offers a whole host of audio processing units in a convenient custom-built rack. In the first instalment of a two-part review, we examine some of the modules available, assess their usefulness, and find out if they're good value.

So many women and so little time. Sorry! So many units and so little space. The mind does tend to wander at times. The problem is intrinsically the same, however: how to fit them all in. Less of the Waughle and down to business, I guess.

Tanrak is a 19-inch wide, 4U-high sub-rack which can house up to 11 plug-in modules plus a DC power supply. The rack is aluminium with a textured black stove finish. The modules themselves have anodised grained front panels with orange switches and lettering. When you're spending a few hundred pounds on your studio, it's nice to get something attractive as well as functional, and the Tanrak range certainly looks impressive. Very professional.

For those handy with a soldering iron, the modules are available in kit form at a saving of between 20 to 35 per cent. The kit parts are the same as those used in the finished modules, and they look very easy to build - though I speak as one who hasn't actually put soldering iron to PCB. If you do run into difficulties, Tantek will put right your mistakes for a standard charge of 20% of the kit price, which seems a very fair deal.

Just a few more words about the nature of the rack and the modules before plugging them in and working them out. The whole Tanrak system has been designed to be flexible. A bus on the back of the rack distributes power to the modules and interlinks the audio lines so you can rearrange the modules' positions while maintaining connections. Each module also has its own set of quarter-inch jack sockets at the back, and the rear PCB houses a Key bus. All modules have been optimised for operation at -10dBv but should operate just as well at 0dBm. It handled all my home studio equipment with ease.

The manual suggests five different ways of connecting the system:

1) Put a signal in the left-hand module, run it through the units and take the output from the right hand module. Individual modules can be switched out so the signal need not run through every one.

2) Using the optional Input and Output modules, perform option 1 from the front panel.

3) Use the rear sockets as a patchbay. While this is certainly feasible, you'd need easy access to the back of your rack. Difficult if it's tucked away neatly in a corner.

4) Extend the rear sockets to a patchbay. This obviously gives you ultimate control over the units but the smaller studio, particularly the one-man kind, will probably be able to manage quite well with option 1 or 2.

5) Use a Mixer module and run the outputs from certain modules onto the stereo virtual earth bus, extracting them with the Mixer, for example, to combine the outputs from several Mic Preamp modules. To do this in stereo, you'd need two Mixers. I never actually had the urge to do this during the review - apart from the fact that I wasn't supplied with a Mixer - but the option is there, and you may just find a problem or two which this method of combination and separation solves, especially if you want to work in stereo.

That's the introduction over. If you've scanned ahead to see how much the system costs, you'll want to know how Tanrak performs. Read on then, gentle reader.

Mic Preamp
Surrounded as we are by mountains of electronic instruments, it's easy to forget the human side of our music - the vocals. I plead guilty, too. As in life, nothing is easy and the best mics are the ones which need a little help to get up to line level. The Mic Preamp does this - and a little bit more.

The basic module provides a 12V power source which will suit most microphones, but it can be set to provide 24V or 48V via the Phantom Power module if necessary. It accepts a balanced XLR input and boosts it to line level. Unbalanced mics can be used, too, by making up an XLR-to-jack lead.

A Sensitivity control adjusts the gain, and an LED shows when it reaches 0dBm, but this is just a guide as you can crank the gain up further. If you do get headroom problems, the -20dB Pad can be switched in to help. Thoughtful stuff.

Up to nine Preamps can be used (eight if you use the Phantom Power module), and the outputs can be collected by two Mixer modules. The Mix control on the Preamps determines their level in the mix, while stereo position is set by the Pan control. The Phase Reverse switch ensures you don't have to spend hours re-wiring plugs because some wally (probably you) wired them up wrong in the first place. We've all done it.

The module also has an Effects Send and Return, so you can plug it in and out of anything else that might take your fancy. In a multi-mic setup, you could even give each Preamp its own EQ module. The permutations go on. And so must we.

Input Module
Surrounded as we are by mountains of electronic instruments, it's easy to forget the human side of our music - the vocals. I plead guilty, too. As in life, nothing is easy and the best mics are the ones which need a little help to get up to line level. The Mic Preamp does this - and a little bit more.

The basic module provides a 12V power source which will suit most microphones, but it can be set to provide 24V or 48V via the Phantom Power module if necessary. It accepts a balanced XLR input and boosts it to line level. Unbalanced mics can be used, too, by making up an XLR-to-jack lead.

A Sensitivity control adjusts the gain, and an LED shows when it reaches 0dBm, but this is just a guide as you can crank the gain up further. If you do get headroom problems, the -20dB Pad can be switched in to help. Thoughtful stuff.

Up to nine Preamps can be used (eight if you use the Phantom Power module), and the outputs can be collected by two Mixer modules. The Mix control on the Preamps determines their level in the mix, while stereo position is set by the Pan control. The Phase Reverse switch ensures you don't have to spend hours re-wiring plugs because some wally (probably you) wired them up wrong in the first place. We've all done it.

The module also has an Effects Send and Return, so you can plug it in and out of anything else that might take your fancy. In a multi-mic setup, you could even give each Preamp its own EQ module. The permutations go on. And so must we.

This gives you front-panel access to the rack. A stereo jack socket and a Key bus input save you messing around at the back of the unit, but all the inputs and outputs are there should you need them. Ten LEDs give a visual indication of the level, which can be boosted or cut. External inputs can be applied to the unit to check levels (now why didn't I think of that?). It really is a boon, being able to check and boost some bits of computer-related music paraphernalia. It's when you get to play with units like these that you realise how useful they are.

The input impedence is 1Mohm, so you can plug just about anything into it. I ran it through my gamut of input busters - and it didn't. Great for DI'ing a bass and other awkward instruments. As with the other modules, it passes its output to the module on the right, eventually ending up at the...

Output Module
This collects the signal from the module to the left of it and offers a handy output from the front of the rack along with stereo headphone monitoring. The line level output is only in mono, but there are stereo ins and outs at the back as usual.

To compliment the Input module, this has a very low impedance (less than 0.5ohms). Impedance matching is rarely an insurmountable problem in the smaller studio, but these two units should be able to handle most eventualities.

The Input and Output modules are not essential to successful processing, but they do make it easy to route a signal through the rack. You could even patch them into your mixer's send and return.

Pro-Gate
This is in fact a noise gate, though Tantek's literature makes a point of not using that phrase in describing the module, mainly to stress its creative uses. Noise gates are often used to control the spurious noise (usually of the white variety) produced by every kind of electronic instrument, the sort of noise which lingers in the background when no notes are being played. You never notice it live, but in the studio, it can make it sound as though your gear's acting up.

A noise gate, if you want to be technical about it, is an amplifier whose gain is unity when the input level is above a pre-selected threshold level. In other words, it monitors the input signal and cuts it off if it falls below a certain level, effectively preventing low-level residual noise from reaching the output.

Applications include keeping an instrument's output silent when it's not playing, and preventing extraneous noises filtering in through microphones. These gates can be a godsend when miking drums, and are handy to have around when someone turns up with a noisy amp and refuses to be DI'd.

The Pro-Gate has been optimised for operating levels of -10dBv (the Input module can adjust levels, should it be necessary) and has variable Attack, Release and Hold controls. The Threshold ranges from 0 to -60dBm, and should be able to handle anything you throw at it.

In the creative department, you can switch in an input from the Key bus so, for example, you could make a bass track follow the bass drum for a tight sound. The controls need to be set carefully to avoid a glitch when the gate switches off abruptly, but that bit's up to you.

Having a gate 'in the system' means you can channel signals through it automatically, and it even helps cut out the noise on digital synths.

Compressor-Limiter 2
Another useful and at times indispensable unit. A compressor reduces the dynamic range of a signal by progressively attenuating the level as the signal gets louder. A limiter reduces over-the-top signals, too, and is frequently used to prevent the odd peak getting into the system where it might over-saturate a tape. It can be a great help when recording vocals, especially when they're performed by singers with little mic technique, and it will also control a signal (from a guitar, say) in which certain harmonics or notes tend to peak above the rest. Both help get 'more signal' onto tape.

Compression is normally in the range of 3:1, so that a 3dB increase at the input would result in a 1dB output level. Limiting, on the other hand, is commonly in the range of 20:1. In both cases, there's a threshold level below which no attenuation takes place.

The Tanrak's Comp-Lim 2 has an adjustable Slope control, giving compression or limiting from 2:1 to 20:1. An LED glows from green to yellow to red to indicate the level of compression taking place. The unit has variable Attack and Release controls and a Key input.

Apart from the sort of merely practical applications discussed above, the unit can be used in an envelope-shaping capacity for creative effects, such as extending decay times and making sounds more percussive. It was easy to use and did its job well.

Infinite Flanger
I like effects units. Even with the almost infinite variety of sounds modern instruments can produce, there's still nothing like putting your latest creation through an effects unit. Flanging is an old effect now, and I hope most readers will know what it sounds like because, as it's impossible to describe, I'm not even going to try.

The Infinite Flanger takes its name from its (nearly) infinite flange ratio, ie. the ratio between the shortest and longest delay times. Clearly, a lot of thought has gone into the design of the module. The dynamic range is rated at 103dB, and the unit has two Bucket Brigade Devices (BBD), one of which is set by a Shift control to produce an offset delay. The Regeneration control strengthens the flange effect, while Mix controls the mix between the original and the delayed signal. There's also an Antiphase function which hollows out the sound.

The flanger can be swept manually with the Man control, or you can plug in (at the back) the Modulation Oscillator or another CV source for automatic effects. I'd say an external modulation source is really essential to get the best from the unit, and you should consider the Modulation Oscillator (see below) as a more or less compulsory addition.

The Infinite Flanger kept me busy for ages. It produced everything from vibrato (used on pianos), phased vibrato (and phased vibrato with funny bits) to wild and whirling sweeps up and down the harmonic spectrum. As it doesn't have a utilitarian function in the sense that gates and compressors do, you tend to feel guilty playing with it for hours instead of doing something productive. Still, all in the cause of a review...

Modulation Oscillator
This produces a CV modulation (0 to 5V) which can be varied from a sinewave to a rising or falling ramp wave. It has two outputs with independent Depth control. It also has a switchable Key/CV input, which automatically adapts itself for either an AC key signal or a DC CV, permitting effects such as amplitude-dependent vibrato, or the creation of complex new waves by external CV modulation. A cycle can be triggered by a Key input such as that from a drum unit or a synth, and there's an Envelope Follower output, too.

The frequency range runs from 1 cycle every 30 seconds to 12Hz. On a dial ranging from 0 to 10, all the vibrato settings occur in the last sector, so tuning can be a little on the tight side.

The module can be used to control any CV device, but as I've said, it's a fine match for the Infinite Flanger just discussed.

We conclude our two-part review of Tantek's Tanrak system of signal processing units, with the promise of yet more modules to come in the near future.

Dynamic Noise Filter 2
Noise is the studio's public enemy number one. One day, of course, all studios and recordings will be digital and quantisation will be numero uno but until then - and until small studios can afford it - we're stuck with analogue signals and noise.

The Noise Gate can help in certain areas, the Compressor and Limiter can help in others. A good noise reduction system is a help all round, but what about recordings you made before you could afford all these goodies?

The Dynamic Noise Filter could be the answer. It's basically a low-pass filter whose cutoff frequency rises when presented with high-frequency signals above a certain level - a similar idea in principle to a reverse compressor. When high-frequency signals are present they tend to mask the noise; when they drop, the unit cuts down on the noise level.

I thought this was too good to be true, but it does work. You can leave the unit permanently patched in to the end of the recording chain, or you can process incoming signals through it. All this is possible in stereo, too.

An LED shows when the unit is filtering, and the Threshold control needs to be adjusted carefully to find the optimum level for the signal; if you set it too severe, glitches can occur as it clamps down on noise during quiet sections.

The device works better on some material than others. If you can hear noise in a piece containing high frequencies, you're pretty much stuck with it unless you resort to filtering.
I used the Filter to clean up some old recordings and threw in a bit of Enhancing (see next unit), too. It won't remove every trace of noise in a piece, but it can reduce it and it is difficult to tell if the signal proper has been tampered with.

Really noisy pieces tend to be the product of much bouncing, and the Filter can help tidy them up if, like me, you're a messy bouncer.

Psychoacoustic Enhancer
Bit of a weird one, this. When the first such enhancer hit the market some years ago at around £1000, it was very much a black box. Listeners agreed it did something to the sound, but no one could quite say what. Research has since opened the box (and took the money) and there are now several budget enhancers on the market.

Tantek thoughtfully tell us how their Enhancer works: it's a mixture of high-frequency boost, compression and harmonic generation. You can hear the HF boost even on so simple a sound as a flute, but is there something else there as well?

Well, sound is all about subtleties, and never is this more true than in the use of the Enhancer. The controls must be set carefully, as you soon learn that it's possible to enhance noise, too. The manual says there is an optimum setting for every situation, but finding it is the trick, as adjusting one control usually affects the others as well.

The Enhancer is particularly useful for giving tired recordings a new lease of interest; the sort of mixes which have been EQ'd and bounced so many times, they sound like rubber cheques. You can place the device anywhere in the recording chain; in a mixer's send and return channel, or direct to instruments as they are being recorded. Plug a drum unit into it, vocals, a synth. Basically, you can enhance anything.

The Psychoacoustic Enhancer works with mono signals only; you need two to process a stereo signal.

Parametric Equaliser
Every recording setup needs good EQ facilities. They should be at the top of your shopping list - after a mixer, a tape machine, and a mic. A Parametric EQ allows you to select a certain frequency, and then cut or boost it. It can emphasise the kick of a drum, control the ring of a cymbal, or trim the sizzle out of a string sound. The dividing line between using EQ for corrective and creative purposes is very thin. My line vanished years ago, so now I just EQ a sound until it sounds right. If you're a purist, slap my wrists.

The Tanrak Parametric covers an impressive frequency range from 3Hz to 37kHz, with cut and boost ranging from ±10dB at high bandwidths, to ±30dB with narrow bandwidths. The figures are automatically optimised by clever circuitry.

A neat unit and a worthwhile addition to the rack, though if your mixer already has comprehensive EQ facilities, you may not consider it as important as some of the other Tanrak modules.

Digital Sampler-Delay
Well, this is the biggy. It's twice as wide as the other modules, and has twice as many controls. The audio signal is not patched into it directly; you must go round the back and do that yourself. It also has Gate In, Modulation In and CV sockets.

At full 15kHz bandwidth, the Delay/Sample time ranges from 15mS to 1.4 sec. This range can be raised from 90mS to 8 sec with reduced bandwidth. The Length control sets the time and the Trim control fine-tunes it, reducing the bandwidth at the same time. Lower bandwidth settings are reflected in the reduced quality of the echoes, and it's a loss that can become quite noticeable, especially with many repeats when the Regeneration control (feedback) is turned up.

The usual impressive, useful and interesting delay effects can be produced - along with some pretty horrible sounds if you twiddle the knobs (in)correctly. You can plug in the Modulation Oscillator for vibrato effects or just to add something extra to the delay, so long as you're careful that the modulation doesn't cause distortion. Increasing the Trim helps combat this, but at the expense of reduced bandwidth. The Mix controls the balance between the dry and processed signal.

Sampling is easy. Set the sample time and play the sound. The unit triggers automatically (though you have the option to apply an external trigger) so split-second finger movements are not required.

A sample is played by pressing the trigger button, applying an external trigger or by a signal at the audio input. The CV input is calibrated to accept a 1V/octave signal from an analogue synth, and a Tune preset can be adjusted to scale the keyboard if required. This allows the sample to be triggered by almost anything, so long as it has compatible CV and Gate sockets on the back.

The Start control lets you skip any unwanted bits at the beginning of the sample; they can appear at the end, but the Length control can then be used to shorten the length of the sound. The Decay control helps extend a sample with an abrupt finish, and is most effective during looping, as it controls the rate of decay of the loop.

Looping, however, is something you should contemplate only if it's absolutely essential. It can take a while to find a suitable looping point and some sounds, of course, insist on glitching no matter what you do. In the (admittedly limited) time I spent with the Tanrak, I never managed to produce a loop which didn't glitch at all, but I came close. The loop only plays when it is retriggered, and every time it's gated a length of sample at zero memory is played, so the initial attack of the recorded sound is preserved.

An Overdub button allows you to mix the existing sample with a new one using the Regeneration control. You can build up new sounds and effects quite easily this way, and I succeeded in putting together my own orchestral stab from a variety of motley sources. It weren't 'alf bad.

You can store different samples in different parts of the memory by using the editing controls to select start and finishing positions. At full bandwidth this doesn't give you much time to play with, and as you increase the time you reduce the quality. Situation normal.

Finally, you can save and load samples to and from tape just as you record and play a sample into the unit.

All in all, this is a super module that really is fun to use. It does produce some background noise, though, which seems to be par for the course for an eight-bit companding system these days. My guess is that, with noise at its present level, the Tantek sampler wouldn't meet a professional studio's demands. Whether or not it falls short of yours only you can say, but it's worth remembering (a) that this sampling delay really is incredibly cheap, and (b) that since I tested the Tanrak, the designers claim to have redesigned the circuitry so that noise levels are now reduced by about 10dB.

The Other Modules
Yes, there are more. The Phantom Power module, a Multi-Delay module, a Mixer module and a Panner-Fader. I didn't have any of these to review, but they must be mentioned for the sake of completeness, and I have no reason to doubt that they're built to the same standard as the other Tanrak modules. Tantek are aiming to produce a new module every two months, so buyers have plenty to look forward to, including - and this is a piece of hot news - a MIDI-to-CV converter.

Most of the Tanrak units can be used with stereo signals, and although I suspect many home users will tend to record in mono and create their stereo image after (or during) much mixing, there are many applications suited to stereo processing - in these cases the Tanrak won't let you down, though be warned that you may have to reconfigure your patches and some of the modules. The flexibility is there, and it must be welcomed and applauded.

Conclusions
The Tanrak system was developed and designed for the home and semi-pro studio, a market that always has one eye on the price-tag and is keen to appreciate value for money. Well, Tanrak must get 10 out of 10 for value. If you buy the kits, make that 11 out of 10.

Let me put it like this. If I were just starting my studio, Tanrak would be on my shopping list, and probably somewhere near the top. But then, if I hadn't seen the competition, I wouldn't know what a bargain I was getting. At the very, very least, send for details of the Tanrak modules and if you don't buy them, let me know which system you found to be superior.

SOURCE:
https://www.muzines.co.uk/articles/stack-in-a-rack/1928
https://www.muzines.co.uk/articles/stack-in-a-rack/1949" rel="ugc noopener" target="_blank"> https://www.muzines.co.uk/articles/stack-in-a-rack/1949
BUILDPLAN:
https://www.muzines.co.uk/articles/modular-effects-rack-project/4210
https://www.muzines.co.uk/articles/compressor-limiter-project/6299
https://www.muzines.co.uk/articles/dynamic-noise-filter-project/6320
https://www.muzines.co.uk/articles/parametric-equaliser-project/6342
https://www.muzines.co.uk/articles/multi-delay-project/6358
https://www.muzines.co.uk/articles/modulation-oscillator/6379
https://www.muzines.co.uk/articles/input-module-project/6403