These are "long geometry" ribbon mics with an obvious internal resemblance to the AEA R-84. They were commissioned by Nady Systems for manufacture by a large microphone vendor in China and are now sold under various brand names. They can be improved significantly with some quality control and modifications.

The stock ribbon motor is really quite decent. But many layers of wind blast protection were added to these mics to reduce the likelyhood of return. These layers sure do work - but the stock sound is slightly muffled, bandwidth restricted and has slew rate limitations.

This is Michael Joly writing, the guy behind OktavaMod. You're invited to contact me directly to discuss your mic needs and discover if modifying your ribbon mic is right for you.

The OktavaMod upgrade removes these mechanical filters and adds acoustical damping. Subjective impression of frequency response extension is improved by about an octave at each end. These modifications produce a great-sounding mic for drum overhead, guitar cabinet or vocal use.

Next, a Lundahl transformer upgrade makes these mics sound more like an expensive classic ribbon microphone. The Lundahl transformer excels at conveying harmonic complexity cleanly, reduces the somewhat "ringy" sound caused by the stock transformer, cleans up mid range confusion and provides picking transient detail not heard with the stock transformer.

Ribbon Sag

Finally, the ribbon is adjusted for proper tension and the ribbon motor mounts tightened. About 30%-50% of the two hundred or so mics of this type I've seen have come from the overseas manufacturer with improperly tensioned ribbons - often with 80% of the ribbon length sagging out of the magnetic gap. (see below).

Stock Mic with Ribbon Sag

This can cause mechanical "banging" noises when the mic is moved - the ribbbon is so slack it scrapes the magnet pole pieces. A slack ribbon also creates a resonant frequency in the single Hz range thus making the mic very sensitive to footfall vibration and can also reduce output if the ribbon is bowed out of the magnetic field. Likewise, the ribbon motor mount is often loose and can wobble in its frame.

You can check your mic for ribbon sag very easily. Listen to it in headphones and gently tip the mic back and forth so first the front face, then the back face comes to rest parallel to the floor. If you hear a sudden "clang" or "clunk" this indicates a severely under tensioned ribbon flopping about in the magnet gap. Not good.

Click "Add to Cart" to purchase the Premium modification - you'll get an immediate confirmation email of your order. By the close of the next business day you'll receive a personal email with your scheduled modification and return ship dates. Questions? Just click "Contact Me" - best, Michael

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Award-winning Microphone Design by
Michael Joly