This is perhaps one of the most peculiar magnetic delays ever mass-produced; instead of relying on a traditional tape transport, the heads are resting on a spinning magnetic disc, somewhat similar to an old-style computer floppy. It is, to my knowledge, the only device of its kind.
I own both a Univox and a Melos unit. Both units have extremely low wow & flutter and a very crisp, bright delay signal. The tone quality is very different from tape-type delays, which makes this unit precious and unique. The inputs distort really nicely, and the unit is very reliable. For this reason, the Echo-Tech was my main stage delay for many months, back in Canada when I was playing live a lot. On the negative side, whevener I send the unit into self-oscillation (which can happen very quickly), it always winds up oscillating on a really high-pitched, ear-piercing note, not pleasant at all… I’ve hit that note a couple of times during concerts, and could feel the whole audience cringing!
The condition of the disc is critical to the sound quality of the EM-200. The disc that came with my Univox was in great condition, so the delays are clear and not noisy. Unfortunately, I can’t say the same about the disc my Melos came equipped with; it has many dents and scratches, which makes one of the heads very noisy to use (think of the sound of a worn-out, scratched vinyl record; if you enlarge the picture above, you can clearly see the damage). I do have a replacement, brand new disc, but unfortunately it’s in Canada, and I’m in Tokyo… Next time I visit I’ll grab it and bring it back, unless I can find a replacement here, or fix my disc with the instructions in the next section.
One interesting feature of the EM-200 is the “two-knob” speed control, which is also unique to this unit. One knob is a 6-position selector, for rough speed adjustment, while the other one allows for minute speed variations. With the fine-tuning knob, I’m able to get flanging tones very easily and reliably, without messing up my main delay tempo. Really cool.
Other points of interest are: an overload LED indicator and a mix knob for the two heads. You can go from head A only, 50/50 at 12, to head B only. This was also very fun to tweak live.
Technical Info / Service Notes
The disks used by the EM-200 are becoming very hard to find. Fortunately, they seem to last a long time, so chances are if you buy an EM-200 you won’t have to change the disk, but be aware that they may be scratched. One way to check is to plug the output of the unit in an amp, put the ‘echo balance’ knob at 10, the ‘echo repeat’ knob at 0, crank up the volume of the amp and listen to both heads using the ‘head mixing’ knob. If you hear strong popcorn-type sounds, you know the disc is damaged…
I’ve written a short article about the disk on the tape media page, which you can access here.
I recently opened up my Melos EM-200 to check out the condition of the disk, and to see if perhaps I’d be able to flip the disc upside down and use the other side. I was very surprised when I found out that, actually, there are two discs sandwiched together. So the picture above doesn’t show two replacement discs, but actually one pair, both of which need to be put together in the machine. I don’t exactly why this is so (perhaps one layer isn’t thick enough to support the head’s weight), all I know is it doesn’t seem to be possible to flip one, or both of the disks, in order to get a ‘clean’ surface. One reason why I can’t do it is that the tiny mounting screws positioned all around the disc are recessed, their head flush with the metal rim, and only 1 of the discs, on 1 side, has the necessary recessed holes to accept the screws.
I was fortunate enough to be given digital copies of documentation for the EM-200 , which I now make available for everyone to share. One document that was given to me was an Email transcript from an engineer that used to service these units. He describes a procedure to refurbish old disks and remove dings and scratches. I haven’t tried it yet; when I do I’ll post the results here.
“The life of the disk really depends on the speed of rotation, so a very fast delay wears the fastest and a slow delay makes it last longer. As long as the heads aren’t scratched up, the disks should last a couple of years, depending again on speed and rotation time. If they are scratched, use a #6000 grit mylar lapping tape and polish out the scratches. One of the principles for the design of the machine was ease of replacement of the media and no need for alignment of the heads. That’s about all I can remember about it – sorry! We didn’t get a lot of them back for servicing.”
Here’s a copy of the owner’s manual, schematics and disk replacement instructions.
|Manufacturer||Melos Electric Co., Ltd. (Japan)|
|Date||Late 70s / early 80s|
|Transport type||Magnetic disc|
|Motor speed||Variable, 6-speed selector + fine-tune knob|
|Head selection||Mix knob
|Delay time||Short/mid range|
|Wet output only||Yes, mix knob goes 100% wet
|Remote Control||Echo on/off footswitch jack|
|Related models||Univox Echo-Tech, and other rebrands.|