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NEW FM PROCESSOR

Even if it took an expensive soundcard or a seperate soundcard that could be directly injected FM Extra support would be something you could hang your aht on. The receivers are out there but the encoder is 10k.

Make it it;s own product for a second computer.

Ready to purchase.
 
Leif,

I'm a ham radio enthusiast as a hobby and was thinking about your processors over the weekend while I was on the air. I have a bunch of boxes (accumulated over time) that are in by air chain. I use a Rane VP12 with an old passive Kahn Symmetra-Peak www.w3am.com/SymmetraPeakBrochure.pdf and a Hughes VIP 110 intelligibility processor in the side chain as my mic processor. I high pass at 180 Hz and low pass at 3KHz. The VP12 has a parametric equalizer that I peak in the middle of the standard intelligibility curve. This combination gives me a fairly concentrated speech level that cuts though the noise when folks are trying to copy me during deep fades and weak S/N conditions.

I'm not sure of all of the details inside the Hughes however it really improves intelligibility and density on speech. I once sold one of these for a large high school arena. They were wanting to replace the sound system because the pubic was not able to here the announcements clearly over crowd noise. The sound system was a large-formant JBL horn system that was covering the seats very well. The combination of a Crown Differoid microphone and the Hughes processor improved the system so much the speakers were kept (still being used today). From what I understand the Hughes processor http://www.google.com/patents?id=7XEiAAAAEBAJ&printsec=abstract&zoom=4&dq=klayman+intelligibility#PPA5,M1
Does some form of spectral analysis on the audio and acts as a multi-band processor automatically adjusting an optimum ratio between vocal formants of vowels, consonants, fricatives and plosives. These are all weighed and adjusted for best intelligibility. It works without clipping or increasing the average level that would affect noise pickup or feedback over a speaker system.

What I'm getting to is I would bet you could develop a ham radio software-based processor with "dumbed down" features and restricted frequency response that hams would purchase at a modest price. The only software based ham processor I'm aware of is this one http://www.dxatlas.com/VShaper/ . This software works however it's audio quality and performance is limited.

It would be nice to have a processor with limited frequency response (100Hz-5KHz with variable high and low pass filters), voice-smart noise gate, multi-band agc with bands optimized for the voice range and distortion canceled clipping. Many hams also record there audio in phrases that they can playback (contesting) so they don't have to be constantly on the mic calling over and over. Most users operate SSB however there are a number of "audiophile" AM operators on 160 and 80 meters. Some of the new Japanese radios have some of these features in DSP however they are the high end and are fairly expensive. There are a lot of operators out there using lesser or older equipment.

Just some thoughts.
 
Speakerman, interesting idea!

The Hughes processor appears to be a 4-band compressor tuned for voice, shouldn't be too hard to make Breakaway do something similar. I might look into it once I have a lower latency version.

What price do you consider modest?

///Leif
 
konbaasiang said:
Speakerman, interesting idea!

The Hughes processor appears to be a 4-band compressor tuned for voice, shouldn't be too hard to make Breakaway do something similar. I might look into it once I have a lower latency version.

What price do you consider modest?

///Leif

Ham radio folks tend to be cheap so around 50 bux would be about right. There is probably some magic price that the average person feels is mad spending money (about he cost of eating out casual dining for 2).

If you restrict the frequency response on the low end and high end you would not cannibalize any of your high-end work to date. Having user adjustable eq also with record and playback for listening to tweaking changes would be handy.

A buddy who does RF design made an RF speech clipper that converts the audio into a modulated 455 kc sideband signal...seriously hard clips...filters through a Collins 455 kc mechanical filter then demodulates back to base-band. This filters out the clipper caused harmonics and provides a loud acceptable voice signal with a high average level. It is a basic RF speech clipper. I would imagine the software based distortion-cancellation clipper could do as good or better.
 
AM sideband -> hard clip -> filter -> demod

..sounds a lot like what Bob Orban was trying to emulate with his Hilbert Clipper!

It does work well for speech, but it's really not that different from how my look-ahead limiters work.

I'll bet I could do even better with look-ahead limiting followed by just a bit of distortion cancelled clipping at the end for loudness. This way I could keep delay to a minimum as well, so that it could be used for realtime conversations (which is a necessity of course) :).

Breakaway HAM.. Has a nice ring to it! I might have to follow with Breakaway CHOP and Breakaway BACON too, but I'll worry about those products later ;).

Will still be a while before I can start thinking about it though. I'm currently developing Breakaway Live, and making further improvements to BBP, and I have a few more things in the pipeline after that.. It just never ends!

How would you suggest marketing to ham radio folks? How would I reach them?

///Leif
 
konbaasiang said:
How would you suggest marketing to ham radio folks? How would I reach them?

///Leif

You could either partner up with an existing ham company ( I will E-mail some possibles to you if you like) or you could simply set your web pages describing the software to show up on searches. In ham radio, the word gets around quickly when a hot new mouse trap hits the scene. Word of mouth would take you a long way. Other advertising could happen later if necessary.
 
Hi Leif:

I have watched your development with much interest. Great job!

On the Hilbert Clipper....

I had an Optimod HF 9105A for ham radio use and found it to be a very interesting processor. I'd like to get one again. I spent much time figuring out the Hilbert clipper. Basically it is a clipper that produces IM distortion instead of harmonic distortion. If you look at a spectrum analysis of the result of the HT clipper, when there are say two tones sent into the HT clipper, other mathematically related (i.e sum and differences) tones are created. Sonically this sounds a little like an audio transformer or tape being saturated. The resulting added frequency components end up adding power to the audio as the frequency spectrum gets denser. This is good for voice, but bad for music, and thus has limited application.

A standard amplitude clipper would not be able to create this same result. However performing a Hilbert transform is childs play in the digital realm as you know. Then you could clip that and un-Hilbert it.

If you add such functionality, please PM me. I'd enjoy hearing more about it technically.

Wish I had the time to study DSP more. I'd love to design audio code to to these things.

Thanks!
Dan
W1DAN
 
Hi Leif,

Just a quick question regarding sound cards.

I tried your software with an M-Audio 192 Sound card and was impressed with the stereo seperation from the MPX output coming off air. Then I tried it on a 192khz capable on-borad sound card from an Asus (HD Audio) motherboard, as listed on your website as a compatable sound card for MPX out on breakaway and I was unimpressed! The seperation was virtually non-existant! In fact, it actually sounded better switched to Mono.
Is there any way of making less exspensive sound cards like this, sound any good for FM? Or breakaway only good with specialist after maket audio cards?

Regards
 
Hi Bigrig!

I have been able to get excellent stereo separation from on-board HD audio.

However, it will depend on what model audio chip is on the motherboard.

For example, Realtek HD Audio 662 supports only 96 kHz sampling rate, whereas 663 supports 192 kHz. Only 192 kHz capable chips can do MPX.

Even for the models that support 192 kHz, you probably have to force the card to run at 192 by setting the Digital S/PDIF output sampling rate to 192 kHz in the sound card's control panel.

What's the exact model number of the ASUS board? (They have a million and one different models). If you give me the model number I'll look up the specs for you.

Best,
///Leif
 
hi Leif,

It's an Asus P5KPL-AM motherboard, i'm not sure how the S/PDIF works but I'm just choosing HD audio with a setting of 192khz in the breakaway control panel for the MPX output and the pilot light is coming on but seperation is very bad.

Regards
 
No wonder! The P5KPL-AM is for AM radio, you should have bought P5KPL-FM :).

Just kidding. According to the specs, this chip DOES support 192 kHz. The only thing missing is to make it actually run at 192 kHz. I don't have a motherboard with a VIA chip to test with, so I don't know exactly where to find the setting, but there is probably a control panel app specifically for the audio chip. In that app you should be able to select 192000 Hz. Usually it'll be the same setting that controls the S/PDIF output rate!

Remember, the Pilot tone is only 19 KHz -- a relatively low frequency. If the chip is locked to 48000hz sampling rate, BBP's signal will be downsampled by the audio drivers. The 19 KHz pilot will still get through, but the stereo subcarrier (23 - 53 kHz) will be completely obliterated.

Remember Nyquist's theorem -- the highest frequency that can be represented in a signal is HALF the sampling rate, minus a few percent for filtering margin. Half of 48 is 24 kHz, and they likely use a filter with a 4 kHz stop-band, so that the true available bandwidth is 20 kHz. There's room for the mono and the pilot, but no more!

If you can make it run at 192000hz, there is no reason at all why you couldn't get perfect stereo separation, just as good as a more expensive card.

When it comes to things like signal-to-noise ratio, on-board audio comes up short compared to better sound cards, but to be honest, this isn't much of an issue when dealing with a processed FM MPX signal. Remember we're squeezing the maximum loudness out of the signal already through compression and clipping, in order to overcome the noise inherent to the FM medium. This technique works just as well against on-board audio induced noise!

By the way, new version of BBP is out:

http://www.claessonedwards.com/beta/breakaway_broadcast_setup_0.90.64_beta.exe


AND, the first alpha of Breakaway Live:

http://www.claessonedwards.com/beta/breakaway_live_setup_0.90.64_beta.exe


Live is a low latency processor with ASIO support, and can be used to feed processed audio to the DJ cans, while BBP's longer latency signal hits the airwaves.

///Leif
 
I'm using Breakaway on a Dell Inspiron 6400 laptop, win xp, with an EMU0202 card.

While the laptop is a dual-core, the machine really needs to be on land power and prefers playing audio from the internal HD, as opposed to a USB drive....the 0202 is a USB external card. WOW! Incredible! I, too, have to lock the EMU card every time upon playing to 192khz.

Breakaway has a very unique sound all it's own. One of the best AGC's I've ever heard. Dying to tweak a full-control version. Dying over here, I tells ya.
 
I hear you, Sgeirk. Loud and clear.

Breakaway Live and Breakaway Broadcast are both entry-level versions.

Next on the roadmap is the midrange version, with intermediate controls (probably similar control detail to full control of an 8200), high-quality FM and low-latency studio processing integrated, touch-screen support, tcp remote, stereo enhancer and other new features.

After that, the flagship full control version.

One thing at a time, though -- I am only one person ;).

///Leif
 
Sorted, it's as if they don't won't you to run it in 192 mode, I found a driver file and had to manually change the code to 192 as there was absolutly option for it in the GUI.

Also Leif I am just trying out Breakaway Live and I'm impressed, you sure this isn't good enough for broadcast?
 
Bigrig, it's plenty good enough for digital broadcasting! That is, you could process for web streaming DAB, DAB+, IBOC (HD2/HD3), DRM, satellite radio, you name it.

However, it's no good for Analog broadcasting. It's a digital-only processor, and is optimized to do *that* job. As such, the signal has the exact same shortcomings (from an FM engineer's point of view) as an 1100, 6300, or a ONE with the streaming software would:

No inter-sample peak control. The built oscilloscopes look nice and tight, but that's because they are (intentionally) not oversampled in Breakaway Live. (In BBP, the oscilloscopes ARE oversampled).
If you hook up an external scope, you will see tiny little micro-peaks above 100%, up to 140% or so, due to them slipping by *between* the samples. This is irrelevant for digital broadcasting, so Live doesn't do anything about it. Fixing that would only use CPU power.

No pre-emphasis, and no pre-emphasis limiting. If you apply 75us pre-emphasis after, for example in an external stereo generator, you'll see peaks over 500%.

Look-ahead limiters - no clippers. Nice, clean, very cpu efficient, but unsuitable for pre-emphasis. Look-ahead limiters simply cannot create the density required to "cut through" todays crowded FM band. On FM it would be several dB quieter than BBP and other proper FM processors, and it would still sound smashed and dull! For an example of what it sounds like when you do this, try Sonos III.

There's also no tilt control or any other analog-type calibration features, since they just aren't useful in live, so I felt it better to keep the gui nice and simple.

All these things can of course be dealt with ... And then we'd end up with BBP. Deja-vu ;).

///Leif
 
Re: NEW FM/AM PROCESSOR checked on actual old oscilliscope

I finally hooked up the ol' Tektronix 454A to see exactly what my modulation density looked like with BBP on the AM signal.

Mercy gracious! I've never seen the ring on the Lissajous circle grow quite so convincingly. ( thanks to +150% )
And the balance between "open circle" and "closed circle" is quite satisfying.
I made a digtal videotape capture of some disco music to show the throb, but really don't know where I could upload it.
I guess it's time to figure out You-tube posting. If I figure it out, I'll post a link.

I continue to be delighted after extended listening.
 
Awesome, Tom!

Yes, youtube is a good place to do it. Should be pretty easy too, as long as you get it into the computer first.

///Leif
 
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