Development of the Sound Studio

(by Kai Tachibana)

This device is closely linked to the beginnings of my development activities. How could that happen?

Rockman X100

At the beginning of the 80’s Tom Scholz (guitarist from the US Band “Boston”) developed the Rockman X100. This was a plastic box that sounded good for electric guitars and was quite expensive for those days! The X100 contains 8 pcs. AA batteries, but after a short playing time (a few hours) were already empty. Well, for the portability he was built: With the clip you could attach it to the belt and operate close to hand. The guitar was connected with a short cable and the headphones to one of the two 3.5 mm output sockets.

Here is a functional overview:

The sounds had it all! In a small space you had a great selection ready. Here is the description of the features and functions:

  • The input stage: Only later, a small gain adjuster [Trimpot] was installed. That had to be, because the X100 quickly tended to overdrive guitars with too loud pickups. No! – Not with distortion – even with the CLN sounds. Of course that was stupid, because in the first versions it was only possible with the return of the volume control on the guitar.
  • A compressor – always on and unfortunately not adjustable. If the effect was too strong, it just helped to turn back the guitar volume knob.
  • A four-step selector for two clean and one overdrive and one distortion sound each.
  • For the different sounds, especially for overdrive and distortion, there were three cascaded fixed filters, which were a kind of speaker simulation. This allowed the guitarist to go directly into the mixer or recording device and had studio-ready sounds available.
  • To top it off, there was an effect section with an analog chorus and reverb. This was done with BBD chips (bucket brigade device). Proper digital delay/reverb was impossible at that time with batteries! The reverb essentially consisted of seven different delays, which were alternately mixed left and right on the stereo output panorama. That would in principle be the original circuit of the manufacturer who had published the circuit as an example in the datasheet (MN3011). Tom Scholz has now pre-hung another (seventh) BBD stage (MN3007) as a „pre-delay“ and as we know today, the application is then pending…
  • The chorus was, as usual at that time, analogous to a BBD chip (MN3007) built. Thus, the player immediately had good sounding sounds on call. Unfortunately, the two stereo effects were compulsive. That is, there were only three possibilities: „Chorus – Chorus and Delay – Delay“. Yes, unfortunately that was not completely switch off …

The concept was good in itself and Tom Scholz has immortalized on various records. As a headphone amplifier also included a matching stereo headphones.

The ESP Pocket Studio

Of course, products that sold well awakened the curiosity of some Asian manufacturers. In this case, the Japanese manufacturer ESP. So it did not take too long and they brought the blue pocket studio PS-10 on the market. In principle, a Rockman copy, but with quite improved features:

  • Chorus (6) and Delay (8) could be turned on or off individually. An overlying LED indicated the respective state. The volume of the delay could be adjusted with a trimpot.
  • Also new was the additional „Normal“ sound (5) – that was the same sound as the first clean sound, but without speaker simulation, so really a „normal“ sound.
  • To this normal sound a quartz-stable 440 Hz tuning tone (5) could be switched on. A great idea that I later did in the development of the Streetman SM-15, a portable, battery-powered 2-channel mini-amplifier for e.g. Street music, also built-in!
  • Two large (6.3 mm – 1/4“) output sockets (10). Left and right, or mono

To switch the sounds, there was a 6-way selector on the front with the following options:

  1. Normal Sound, with 440 Hz tuning tone
  2. Normal Sound
  3. Clean 1 Sound
  4. Clean 2 Sound
  5. Overdrive Sound
  6. Distortion Sound

The volume was adjusted with a slider (4). Completely musician-friendly, the ESP people had finally integrated two large 6.3 mm (1/4 “) jack sockets in addition to the small 3.5 mm stereo headphone jack (7) (10, 11). So you could connect the output with a normal and standard jack cable to a mixer or amp.

With power supply!

Also new was the power supply with two voltages (+6 V and -6 V) on a 3.5 mm stereo jack plug. Unfortunately, there was the problem that with only half plug plugged this power supply burned down … Well, simple transistor stabilization, which was not short-circuit proof. Since the housing was glued, you could forget a repair…

Import to Germany

The ESP was not much cheaper than the Rockman, but offered the better features. So it was interesting for the musician. Bernhard Kurzke, owner of the legendary No1 Music Center (retail) in Talstraße, Hamburg/Germany, and MS Music Service (wholesale) and founder of the Nobels brand, contacted ESP in the mid-80s and imported the Pocket Studio to Germany. It was sold through wholesale. The ESP Pocket Studio was also exhibited at the Frankfurt Musikmesse (NAMM).

The ESP problems

Unfortunately I got a lot of broken Pocket Studios on the table within a short time. At that time I was the repairer of No1 Music Center (today No1 Music Park) in Hamburg/Germany. As customers there were the Scorpions, Alexis Korner, Pete Townsend, Frank Zappa, Lake, the Hollies, Otto Waalkes, Rolf Zuckowski, etc., just to name a few that I can think of.

As I said, the ESP Pocket Studios died in rows, especially the power supplies. For some fundamental errors of the ESP Pocket Studio I made some suggestions for improvement, which Bernhard Kurzke then passed on to Japan. And – hard to believe – the Japanese improved the production accordingly.

The Rockbox

Suddenly there was the rumor that there was another, similar device and even made of metal, which would be an improvement, since unfortunately the ESP had only a rather soft plastic housing. The screw connections e.g. went down very fast. And supposedly, this new model should be only half as expensive as the Rockman or the ESP Pocket Studio.

Bernhard got such a part, the „JHS Rockbox“ and gave it to me for evaluation. Then he informed the Japanese: „Either the ESP Pocket Studio is drastically reduced in price, or it would lose the rights in the market.“ The Japanese were persuaded and finally gave up the production of the Pocket Studio. John Hornby Skews (English wholesaler: short JHS) had the Rockbox developed by designers based on Rockman and Pocket Studio. At the Taiwanese manufacturer Phonic – at that time still a manufacturer of medium size – he had commissioned the production. Not only did I recognize the improvements of the Rockbox in the analysis, but I also noticed some quirks that would disturb guitarists. I then made a list of improvements.

Sound Studio 1

Bernhard sat down with John and offered to let us make our improvements available to JHS. The fit, the JHS had great interest with a mature model exclusively to serve the English and Irish dealers.

And so the two devices emerged: „NOBELS Sound Studio 1“ (SST-1) and the „JHS ROCKBOX“.

Sound Studio 1X

Meanwhile, there were problems with the Taiwanese manufacturer Phonic. Our devices suddenly came as a copy with different color and imprint on the market. As a result, we naturally had to part with Phonic. Luckily we had already made new contacts in Korea before. To stand out from the Phonic era, we developed the Sound Studio 1X. So X like extra! The devices were then manufactured by the Korean manufacturer Muse Inc., who later also produced the effect pedals.

For the new functions we came up with many ideas that we could quickly implement. For example, we built a controllable noise gate. Or made the last of the three fixed filters (treble ~ 4 kHz) in the peak frequency (Tone control, front) adjustable. Then an additional mini-pots for the drive intensity (Overdrive, Distortion).

Yes, these mini knobs are pretty much … there have not been any reasonable mini-pots so far. So mini-knob with the right button. Unfortunately that was a problem as these buttons often broke off. They simply were not designed for continuous operation. Only later there were the good and stable V9 controller (Alps, Alpha, etc.).

The absolute highlight, however, was the installation of an electronic signal switch with remote socket, which could be switched from any set sound of the selector switch (for example, to Clean 1) to Distortion.

Headroom +

Finally, we modified the dual power supply with very simple means, so that instead of +/- 6 volts delivered now +/- 6.6 volts. After all, a total of 1.2 volts more headroom!

Comparison of the devices

Rockman ESP Rockbox SST-1 SST-1X Funktion
X X X X X Battery operation
X* X X X X Gain control (* later version!)
X X X X Normal Sound
X X X X Effects individually switchable
X X X X 440 Hz tuning tone
X X X X Large jack sockets (1/4“) for the output
X X X X Send/Return Effect-Loop
X X X X Control for Delay
X X X X LED for Chorus
X X X X LED for Delay
X X X X Control for Delay
X X X Different LED colors for Chorus, Delay
X X X Control for Compressor
X X X Control for Chorus
X X Short circuit proof power supply
X X Overdrive, distortion adjustable
X Remote input to switch to distortion
X Higher output voltage (+/- 6.6 V)
X Noise gate, adjustable
X Peak Treble Filter, Freq. adjustable

Here you can see the functions that have been built into Sound Studios over time. Surely that is not an outstanding engineering knowledge yet. But due to my experience as a technician and the regular contact with the customers, I could add some valuable features with relatively simple means, which made the SST-1 and later the extended version SST-1X internationally successful for a very long time.

If you want to hear and see the SST-1X, you can watch this video from Oliver Hartmann (YT: hartguitar)! Thanks to Oli for the great performance!

And? – What happened next??

Yes, that was the beginning for me in the world of electronics developers. It was so much more interesting than repairing broken devices. We tried out, wrote instructions in German and English, traveled to the Far East, developed test methods and much more!

And it went on rapidly, because at the same time, a young man (Heiko B.) worked as a temporary help in the keyboard department. His enormous skills as a programmer quickly became apparent. Since we had the completely crazy plan to make the Sound Studio 1X programmable. And then we really immersed ourselves in the development of products for musicians.

What has become of it? Well, the legendary Sound Studio 19 (SST-19). The world’s first programmable effects unit for guitarists! What we were allowed to experience is enough material for many more blogs…

SST-19X

SST-19 „- The first programmable multi-effect device for guitarists