Treatment of shortwave sounds

G`day everybody,

I`m working a lot with shortwave-radio sounds. Thanks to an excellent radio the audio-quality is quite acceptable. My problem is, some of that recorded material that I find highly interesting, contains too much hissing.
I have experimented a lot with equalizers, notch filters, gates, compressors etc. but the results are not really satisfying.
I suppose, the physical problem lies in the fact that the white noise is spread over the complete frequency range. So as soon as I filter resp. eliminate specific frequencies, e.g. a voice sounds like being spoken into a tin can or otherwise artificial.
Usually I help myself with adding a small amount of reverb to it. This helps a bit but makes it often tougher to get the voice more dominant in the mix.

Don`t get me wrong: I enjoy the dirt & inadequacies that come with this medium & want to maintain its character but need to reduce the noise a bit in order to achieve e.g. more language comprehensibility.

Anyone out there who also works with that sort of “difficult” material?

Any suggestions regarding your experience with combined use of special plug-ins, smart equalizer adjustments whatever are higly appreciated.

Best wishes


I have a friend who did some extensive work in editing shortwave signals for a song he did. Much of the time, he left atmospheric static in there for effect because it was “supposed to sound like a shortwave radio”, but he may have a few tricks up his sleeve to bring out and improve the quality of the broadcasts.

However, I think much of it will have to do with the same types of operations to the link Ulf provided.

Hello Ulf & John!

I remember I have read about the IZOTOPE restoration bundle lately & it got an excellent reception.

Indeed that might be a rewarding investment.

Thanks you guys!


I’m a big fan of Izotope. They put out some really inventive stuff. I currently have Ozone and Spectron and am planning on getting Nectar once I research how it stands against the big players in pitch correction.

Dear John,

I think Stutter Edit does some nice things, too, though the article I read about Nectar didn`t sound too promising.
The delay often seems to cause cracking sounds when the delaytime gets changed. The doubler-module that creates additional voices sounds quite artificial. Also the author of this article complains about the graphics: Nectar displays tiny pitch variations and vibratos as a multitude of graphic bars which need to be “re-collected” later syllable by syllable to work efficiently with them. Not sure, if IZOTOPE provides demos to test those things.

Best wishes


Hi Joan,
I got a response from my friend.

The long and short of it (pun somewhat intended) :slight_smile: is that, if you are working with signals you have already recorded, then the process is pretty much what we have already gone over.

But if you plan on recording more shortwave signals, here’s what he said: (pardon the lack of male / female distinction).

It actually sounds to be that the problem he has is a low carrier-to-noise ratio. That is, the amplitude of the RF radio carrier signal is not of a sufficient strength to differentiate itself against the noise floor. It’s like being too far away from your favorite radio station. the signal is just too weak and you get a lot of noise and bleed over from other signals.

Unfortunately there’s nothing you can really do about that for the stuff you have already recorded. It is what it is. If he is trying to get new signals off the air with more clarity I would suggest a hi-gain horizontally spaced yagi antenna appropriate for the specific meter bands he is looking to capture. Or even a medium gain antenna will get another 5-8db of signal strength off the noise floor.

I haven’t tried it yet but this guy is making yagis for the 2 meter band frequencies out of PVC piping and old metal tape measures. It’s actually pretty kick ass - portable and not too expensive. It’s a great way to increase the reception of a SWR.


Hi John,

thanks so much for your investigations! I appreciate that a lot!

The fact is, most of the material I use had been recorded in the late 80s/early 90s, mostly on cassette-tape.
At that time I have experimented a lot with various kinds of antennas to improve reception, I even talked to one of my all-time heroes, Holger Czukay whose music had drawn my intention towards shortwave radio. Hes a very kind and witty person but he was not in the mood to have some "tech talk" about treating shortwave sounds... I got a huge archive, so I believe Izoptopes RX 2 should be the perfect choice for me.

Nowadays I have no problems with catching a strong wave for I live out in the country, which means less neighbours = less electro smog & my recording equipment is much more sophisticated.

Again thanks for your time & all the best!