Previewed at Frankfurt earlier this year, the Elka-Orla X-50 portable organ is now just starting to appear in the music stores up and down the UK. We've managed to get hold of one of the first units to arrive in the country, and so we thought that we should 'take it apart'.

There has been a good deal of rekindled interest in single manual portable organs over the past two to three years. Especially with regard to recreating the old Hammond tone-wheel sound. As I expect you know, Hammond stopped producing tone-wheel organs in the sixties as a result of the very high costs involved in producing an electro-mechanical instrument. They've moved on to electronic and LSI instruments which serve the home organ market better. With the exception of the B3000, and the latest of their portables, Hammond seemed to have neglected the sound that they created and that became so fashionable.

The only portable organ that really seemed to come anywhere near the Hammond sound, up to five years ago, was the Crumar Organiser, which although suffering a lot from hum and noise, had a very nice sound to it. A couple of years ago Korg introduced a single manual instrument known as the CX-3, and at almost the same time, Roland came out with their VK-1 portable, both instruments using the nine drawbar system (see later) and with similar features designed, in essence, to recreate the tone-wheel sound.

Now Elka have come out with a single manual portable, which offers much the same features to prevent the Japanese from having everything their own way. Have they succeeded? Read on and find out.

Why then, do so many manufacturers strive to recreate an 'old fashioned' sound, and why is this sound so popular? Well firstly, as in most aspects of music, a natural sound is more pleasing than an electronic one. Electronic organs, by their very nature do not produce natural sounds, but there is a difference to be realised between an electric organ and an electronic one. Many of you will, I'm sure, be familiar with this point. The Hammond tone-wheel instruments were the 'Rolls Royces' of the electric organs and they functioned by spinning a series of metallic wheels, shaped rather like a 50p piece, in front of a magnetic pick-up. There was a separate wheel for each tone — most Hammonds using 95 tones — and each wheel was set on a common shaft, so that just one motor was required for spinning all the wheels. The shape of each wheel was such that it generated a perfect sinewave signal in the pick up.

The beauty of the Hammond system relied on the fundamental principle of the superimposition of sine waves; which basically means that you can create any waveform by adding together sine waves of different frequencies and amplitudes. This is the principle on which most computer based systems (such as the Fairlight CMI) function. For each note of the Hammond organ there were nine harmonically related sinewaves which could be mixed together in varying amounts using drawbars; so with a nine drawbar system, each drawbar having nine different positions, it is possible (so I'm told, but I can't see how the figure was arrived at) to create 253 million different musical tones! It is clear now why the drawbar system lives on. Other characteristics of the tone-wheel sound will become clearer as we look more closely at the instrument in question, which we must now do.

The X-50 is a portable organ, so the manufacturers claim, meaning it should be relatively easy to move around, as well as being able to withstand the knocks and biffs it will undoubtedly receive if it is gigged for any period of time. I can report that it is portable measuring 40" x 15" x 6" when it is in its carrying case. The X-50 is actually built into its case, which is what I would call a road-case. That is, it isn't heavy duty enough to be called a flight case, but it still is rigid enough to be taken on the road to protect the instrument. A hinged lid sits over the top of the unit, and can be fully removed ready for action.

The control panel surfaces are rather interesting in terms of material and design. Surprisingly they are a moulded plastic, but which have been sprayed in a textured metallic grey paint. This gives the impression that the panels are in fact anodised aluminium or similar, and make the instrument 'feel' a lot more substantial. The X-50, overall, seems to have something of a Gothic character about it, which I suppose is rather appropriate for an organ.

The X-50 has several different types of control mechanism. We have the nine drawbars, which can be seen quite clearly in the foreground of the internal photograph. These have a very positive action, and feel as if they would last for years. They are numbered, as were the original Hammonds, '1' through to '8', thus each has nine positions (the ninth being fully in). Situated just above the keyboard — for fast changes, are a series of momentary push switches each incorporating an LED indicator. The switches are fast and efficient to use, and ideally suited to their task, which involves the selection of drawbars or one of the seven presets, and for introducing one or more of the four harmonic percussion options. The X-50 has no rotary controls whatsoever, all the other adjustments, and parameter changes are made using laterally mounted slide switches positioned above the momentaries.

The X-50's keyboard is, by obligation, a 61 note (five octave) C to C type. Anything less just wouldn't be enough, and the Korg and Roland would leave the Elka standing. I must say that I liked the action of the keyboard. In a way it is similar to that of the Hammond, though a bit more plastic. The action is lightish, so glissando slides up and down the keyboard leave your fingers more or less intact. Internal examination revealed that the Elka uses single spring contacts and LSI switching.

Voicing

Well now, what about the sound of the X-50? My main complaint comes not so much with the sound of the instrument, but the balancing of the tones across the keyboard. For example, if I start with the 8' drawbar alone fully extended and play a simple scale of C up the keyboard, it is possible to hear the change in amplitude between the B of the proceeding octave, and the C of the next. Now we all know what is happening here don't we? No, well for those who haven't twigged I shall explain.

As with most electronic organs, the sinewaves are obtained by filtering square or sawtooth waveforms. If you pass a waveform through a low pass filter it will remove all the harmonics, and if the waveform is filtered heavily enough only the fundamental sine-wave will be left. It is a relatively expensive business building filters for every tone, so they share filters, in this case one filter per octave of tones (12), which means that the higher notes are being more heavily filtered than the lower ones, consequently, they suffer a decrease in amplitude, so that when the next tone of the octave above is compared to the top tone of the lower octave there is a discrepancy in their amplitudes.

In the case of the X-50 the amplitudes vary by around 50%, but because of the logarithmic response to volume of the ear, this difference doesn't sound as bad as it sounds (if you get my drift). Anyway, the overall effect of this, especially if you have had your attention brought towards it, is somewhat distracting, especially if you are playing just single notes. I also felt that the upper octaves of the keyboard were less powerful than the lower ones. To my mind they should be given a larger amplitude. True there are separate treble and bass tone sliders, but the effect is not exactly the same. The actual purity of the harmonic drawbars themselves is not in question. They sounded good, and 'scope examination revealed them to be around 97% sinewaves, with the hint of extra harmonics in fact giving some extra body.

There are a series of eight push buttons associated with the voicing of the keyboard. One activates the drawbars, whilst the remaining seven proffer various preset combinations of the drawbars. After much frustration, I managed to work out that these presets were composed as follows:

Full Organ	888888888
Vox I	808080888
Vox II	558880000
Vox III	888000500
Theatre	808808008
Bright	800000448
Jazz	808000000

These are as close as I could determine the preset voicings. For those unfamiliar with the system, the numbers refer to the setting of each drawbar with the first number being the 16', the second 5⅓ and so on through the nine — 8', 4', 2⅔', 2', 1⅗', 1⅓' , and 1'. So if you possess a drawbar organ you can try these settings out for yourselves.

The remaining four momentary switches are used to introduce harmonic percussion. Not many organs offer this many percussion footages. I found it rather nice to use the 5⅓' setting, the others being 4', 2⅔', and 2'. The decay rate and percussion volume can be adjusted by the sliders.

That then is the backbone of the organ, however there are several additional effects that serve to enhance the organ's sound, and to further simulate the old tone-wheel sound.

Extra features

Firstly there is a slider marked Noise Attack, which is more often known as key click. The origins, and desirability of such an effect are rather interesting to analyse. Originally manufacturers did everything in their power to eliminate the noise made by the bouncing of the key contacts when they 'made'. The Hammond Organs were initially amplified with their own custom system which had a bandwidth of only 6 kHz. Consequently much of the key noise was removed. When wider bandwidth amplification systems were used, this noise cut through loud and clear, but such was the music of the time that this clicking gave the sound an added percussive bite, and therefore became very popular. With the advent of transistor switching these clicks were eliminated, but to retain the old sound electronic click simulation circuits had to be included, and that's the reason for this feature, and I must say that Noise Attack certainly does add some guts to the sound of the organ. 'Noise Attack' summons up images of a futuristic sonic weapon confrontation — quite an apt description of certain bands' outputs.

Tube distortion is a similar phenomenon. Transistor amplifiers are too clean and pure to simulate the overdriven Leslie timbre, so Elka have to build in a distortion circuit to muddy things up. Unfortunately, they don't really seem to come too close to the mark with this one, tube distortion sounds more like a cheap fuzz box, than the 'warm' distortion of an overdriven valve amplifier.

Finally, we come to the rotary cabinet simulator. This consists of two switches (rockers) to the left of the keyboard — an ideal position for this effect which corresponds, to some extent, to the pitch bend or more strictly modulation performance controls of the synthesiser. The simulation is as good as any I've heard, with breaking and acceleration between the two speeds (fast and slow). A slider can adjust the relative rotation speeds as necessary.

On the rear panel is a master tune control, and an output line socket (jack) and a DIN connector for the opto swell pedal. A bit cheap having a DIN plug for this type of instrument, I thought. The swell pedal is a standard accessory, whereas the leg assembly (with carrying bag), is extra.

So, at £595.00, is the Elka-Orla X-50 a worthwhile investment? Well I must say I liked it a lot, despite some of the relatively minor criticisms I had of the instrument. It's well built, looks okay, nicely laid out, and above all sounds pretty good. As to whether it is better than the Korg CX-3, or Roland VK-1 and VK-09 is debatable. It is a bit more expensive now than its rivals, but otherwise there is little to choose between them, in particular between the X-50 and CX-3, which in terms of features are almost identical. Still, at least the organ lives on — I'm very pleased to say.

The X-50 is distributed by Elka-Orla (U.K.) Ltd, (Contact Details).