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We’re getting closer to a releasable version!
Slow Sweep added. This sweep is affected by de-emphasis, so if you have no choice but to use an external stereo encoder with pre-emphasis built in, you can now use the L/R PEQ and the slow sweep, look at an off-air modulation monitor, and adjust the PEQ for maximum flatness (that is, constant 100% as the sweep goes from low to high).
Multi-threading improved: On dual-core and HyperThreading systems it will now run the clippers in a separate thread from the rest of the audio engine, for better load balancing. BBP didn’t run properly on my Pentium-D 3.0 GHz before — now it does, even in maximum quality mode.
Multiple instances (purchasable option) added! The installer now lets you choose the number of instances (up to 4) to install.
Added "I/O Configuration" button to the Settings page! (Why didn’t I think of that?) Thanks to Matt (Switch1197) and Rick (RRP) who each pointed it out separately.
Uninstaller improved — doesn’t forget files anymore.
Feature-wise, BBP appears to be done. If anyone can find any reproducable bugs, or have any ideas for how to make it more user friendly, please speak up! 🙂
http://www.claessonedwards.com/beta/bre … .90.49.exe
///Leif
It’s just getting better and better… 😀
I have two requests that may be worth adding.
1. Test tones:
A. Could a 30Hz/40Hz tone be added to test external exciter AFC control (or lack of it)?
B. Burst mode where the tones are turned on and off for short intervals like 1/2 sec on/ 1/2 sec off. This would be handy with request A. Low frequency overshoot due to AFC instability is a common problem with many pro and homebrew FM exciters. Booty bass can sometimes make an otherwise clean signal sound lousy when the exciter AFC is motorboating around trying to deal with the ultra lows. By checking the AFC control the user can adjust the BBP bass enhancements that is best suited for their exciter hardware (external of course).
C. Add a Left only or Right only option for testing each channel seperately for signal path imbalance or phase error (for checking distribution amps, mixer consoles, air chain signal path ect…)?
D. This request may be a bit over the top from a technical sense and may not be useful to most BBP users but I’ll ask anyway 😐 . Add a noise generator output (white) filtered to 16kHz (linear-congruential algorithm to generate a pseudo random signal output) to check FM channel occupied spectral bandwidth. This method basically fills up all of the alloted spectrum uniformly for easy analysis of the FM channel (both the main channel and MPX). I find this process aids in checking the bandwidth of antennas relative to the radiated signal. Narrow band antennas can skew (or tilt) one of the FM sidebands if it’s not tuned to center frequency causing a loss in loudness and generate splatter in the sibilance frequency region. Asymetrical sideband radiation makes multiplath problems within the coverage area that much more pronounced.2. BBP & BA Live display enhancements.
A. For the multiband AGC bar graph add the frequency band information either at either the top or bottom of the window. it would be nice to know this information breakdown when switching between various presets.💡 Here is a possible future option that in my opinion would be hugely useful. 💡
Create short specially encoded mp3 files that can be placed into a play list that can tell BBP or BA Live to switch presets on the fly. This to me would be really useful if changing music types on automated systems ie. from R&R to Dance, Jazz to classical… you get the idea. 8) Free form FM radio plays eveything under the sun. It sure would be nice to maximize the sound quality that BBP offers by automatically adjusting it to the music style of the DJ.Hi Sparky!
These are EXCELLENT suggestions!
30 Hz sine test tone and 30 Hz burst mode (30hz sine for 0.5 seconds, silence 0.5 seconds, 30hz size inverted for 0.5 seconds, silence 0.5 seconds) will be excellent additions.
Left/Right is certainly possible, but complicates things a bit for composite output. Should the composite output just stick to mono perhaps, as I would otherwise have to run the test tones where this is applicable through the stereo encoder.
Noise generator is also valid, but complicated in practice:
I could use the clipper algorithm to generate extremely compact band limited white noise, it would stay perfectly within +/- 75 kHz deviation and within the allotted frequency band. The complicating factor is that this assumes mono transmission. An FM stereo channel can potentially use an extreme amount of bandwidth (imagine a 57000hz tone at +/- 75 kHz deviation — not a common usage scenario, but still). Some countries (The Netherlands for example) use spectrum mask standards (ITU-R SM.1268-1 for example) to enforce the amount of bandwidth a given station is allowed to occupy. But, I digress. 16 kHz white noise may not be adequate — would we need 0 – 54 kHz white noise, or perhaps 16 kHz noise into the stereo decoder?
There’s no room to add the frequency band information in the gui, but I could add it to the tooltips. Would that work?
All of the above, I’m willing to add to the current $199 BBP, provided I can wrap my head around some of the things.
Dayparting is something I’m already planning for the more advanced future versions of Breakaway Broadcast, but you have an EXCELLENT idea. Imagine a "Save Preset as WAV" option, and all you have to do to recall that preset is to play the resulting 1-second wave file. Naturally, it would have to use some kind of audio encoding scheme to survive mixers and whatnot, but I figure, if C64 programs could survive on cassette tape, why should BBP be any worse? 🙂 Holy 1984, Batman, but I like it!
More than a few people have told me I’m insane for releasing an algorithm of this caliber for $199, but I keep answering — just wait for the more advanced versions, there’s no shortage of useful features that can be added to make the more expensive versions worth buying. I’ve set the bar high for myself, but not unrealistically so, and I do like a good challenge 🙂.
Best regards,
///Leifquote :“30 Hz sine test tone and 30 Hz burst mode (30hz sine for 0.5 seconds, silence 0.5 seconds, 30hz size inverted for 0.5 seconds, silence 0.5 seconds) will be excellent additions”Cool. I would imagine the DJ’s would like this feature too for the BA Live. It would be a simple way to set the PA system max volume without hitting that magic point where you get woofer overextension. Go beyond that point and damage can occur. It’s nice to know where the sonic limitations are for the hardware you’re working with (crash points).
Future thinking on this subject, it might be valuable to offer a few different on/off times. 1/4 sec, 1/2 sec, 1 sec, 2 sec, 5 sec. I would imaging lots of users might find the array of differing times useful.
Also why limit the on/off function to only 30Hz tones? Why not make it available to all tones in the setup tool suite?quote :“Left/Right is certainly possible, but complicates things a bit for composite output. Should the composite output just stick to mono perhaps, as I would otherwise have to run the test tones where this is applicable through the stereo encoder.”This does not need to be used with the internal BBP stereo encoder. I was thinking it would be more useful for applications where the MPX signal would not be needed. But if it can also be applied to MPX composite the more the better. Great feature for checking sub-to-main and main-to-sub modulation x-talk on the mod meter.
quote :There’s no room to add the frequency band information in the gui, but I could add it to the tooltips. Would that work?Sure, or have a tool tip window pop up when you place the cursor over the bar of interest. Just a thought.
quote :“Noise generator is also valid, but complicated in practice:”Ya!… no kidding. I keep forgetting that you generate the composite MPX in software.
quote :“But, I digress. 16 kHz white noise may not be adequate — would we need 0 – 54 kHz white noise, or perhaps 16 kHz noise into the stereo decoder?”I guess the best way to envision the big picture to help you sort it out is look at it from a hardware perspective. The white noise is applied directly into a hardware MPX generator L&R inputs. The 16kHz white noise modulates both the L+R and L-R channels equally. Left and Right gain flatness is crucial. The objective here is to check FM occupied bandwidth with the MPX operating normally. White noise stuffed into the L+R L-R matrix pushes the exciter, RF chain, and antenna bandwidth pretty hard and can reveal tuning mismatches or other lurking nasties. But again this may be beyond most users needs. Perhaps as a more useful tool is having a white noise source as a stand alone test tone, or for testing hardware setups where the composite is generated by dedicated hardware (no BBP MPX). Or as another use the BA Live DJ can use it to blast the dance floor to wake every one up (or send them home at closing time as a sonic cattle prod???)
quote :“Dayparting is something I’m already planning for the more advanced future versions of Breakaway Broadcast, but you have an EXCELLENT idea. Imagine a “Save Preset as WAV” option, and all you have to do to recall that preset is to play the resulting 1-second wave file. Naturally, it would have to use some kind of audio encoding scheme to survive mixers and whatnot, but I figure, if C64 programs could survive on cassette tape, why should BBP be any worse? Holy 1984, Batman, but I like it!”Doubly cool.
You can take a couple of different approaches in developing specialized signaling for this task.1. Borrowing from the FM transmitter remote control play book. Back in the day transmitter control feed back was done using sub audible tones 10-20Hz riding on SCA subcarrier. Data was encoded using MSK (Minimum Shift Keying) techniques on these tones. Basically changing the sub audible tone phase (like FM) allowed a simple way to send binary data. In the case of BBP & BA Live it does not have to be a very lengthy message. A few cycles is all that is needed.
2. Cycle burst. The wave file uses a predetermined and number of tone cycles and predefined tone frequency to indicate which preset to switch to. BBP & BA Live could be made to "look" for these freq cycles and use them as a means to accomplish the task. The beauty of it is, BBP and BA Live with its look ahead processing can detect and prevent this specialized waveform from passing on through to the output where it’s never heard. But at worst a few cycles of say 1kHz amounts to an tiny audible click.
3. Phase comparison. Using a few cycles of a predetermined tone, encode the left and right channels with it but vary the phase of one. The phase difference between the left to right determines which preset to use.These are just a few ideas I cooked up. With more time to think about it I probably could come up with more. Need any help trying these ideas just PM me. It would be fun to help in this regard.
Cheers
Sparky
Howdy!
The one major reason I can think of for not simply adding another control for "burst mode" for all test tones, is that I want to make it as simple as possible for the user. It’s much easier to explain in the documentation to "Select 30Hz Burst" than to have to set three controls correctly, especially since the other controls may then be left in the wrong state for other operations. Interesting application for BA Live too, I’ll definitely think about it 🙂.
There’s already tooltips that pop up when you place the cursor over the bar of interest. There have been all along. Geez, doesn’t anyone notice all the effort I spent on these little things 😀.
For white noise to modulate L+R and L-R equally, the noise in L and R must be completely uncorrelated. Easy enough to do, perhaps! It’ll be a useful feature indeed — BBP is a broadcast processor after all.
For the Save Preset as WAV, I was thinking somewhere along the lines of encoding data with multiple tones at the same time. With an FFT it’s easy enough to decode that, and it’s indeed easy to mute the output so that the tones are never heard. I was thinking of transferring the entire preset this way, but this may be over-ambitious — it would be much easier to just recall a saved slot! If Breakaway Broadcast Pro Ultra Plus Advanced (no, I don’t know what to call it yet) had 8 preset recall slots, and I include 8 ready-made MP3 files to recall these slots, I would save myself a lot of grief. For one, I couldn’t export MP3 without licensing an MP3 encoder, but if I just include pre-encoded files, we’re home free. Also, the detection could be very quick and basically fool-proof this way — the chance is basically nil that music would have exactly that combination of frequencies, especially if I make it a multi-stage sequence. This could be really really useful — even more so than dayparting/scheduling. Simply embed the sequence into the theme/intro of the show, and it’ll be all automatic.
Breakaway Broadcast indeed has plenty of look-ahead to mute the output. Breakaway Live doesn’t, but who cares — the tones don’t need to be muted in the studio. It’s not like they need to be full amplitude, -40dB down should be plenty strong enough.
Best regards,
///Leifquote :The one major reason I can think of for not simply adding another control for “burst mode” for all test tones, is that I want to make it as simple as possible for the user.Sure makes sense. You should poll the user base to see if they would want this.
quote :There’s already tooltips that pop up when you place the cursor over the bar of interest. There have been all along. Geez, doesn’t anyone notice all the effort I spent on these little thingsOh it didn’t go unnoticed. I was refering to adding the frequency range information for that band/bar that is pointed to. i.e. Band 2 of 6 – 300Hz to 600Hz (made up numbers)
quote :For white noise to modulate L+R and L-R equally, the noise in L and R must be completely uncorrelated. Easy enough to do, perhaps! It’ll be a useful feature indeed — BBP is a broadcast processor after all.Every little bit helps too…
1. make BBP kick ass.
2. Best sounding FM signal for Pro or Pirate alike. quote :had 8 preset recall slots, and I include 8 ready-made MP3 files to recall these slots, I would save myself a lot of grief.Yep exactly as I was thinking. Perhaps use the telephone touch tone frequency combinations (15 extended tone set). Non harmonically related, easier to FFT.
The number of sets could be expanded easily by stringing 2 tone sequences together (like dialing a two digit phone number) to give you 225 possible combinations. Using two tone digits further prevents false positives from music energy.
You may not remember this but satellite program providers used this technique to signal cable TV providers when to insert local programming automatically. These tones were clearly audible. Short 6-8 tone bursts… beep bip boop… click something happened somewhere out in TV land. CBS radio network did the same thing too back in the 70’s during network programming feeds. Worked great for stations that were unstaffed and automated overnight.Now if you want to get really fancy, reserve a few tone sequences for control items outside of audio processing. How about a tone sequence to issue a turn on or off command to a transmitter? With an LAN capable AC power switch, BBP can issue a command packet to the designated IP address and… click. 8)
quote :…but if I just include pre-encoded filesExactly. Encode and name them (tag) for the current presets that are most popular.
quote :This could be really really useful — even more so than dayparting/scheduling. Simply embed the sequence into the theme/intro of the show, and it’ll be all automatic.Glad you like it 😀 I’ve been wanting something like this for a long time. I would recommend seperate files though instead of mixing it into the program start/stop. This keeps it simple and can’t be screwed up.
quote :Also, the detection could be very quick and basically fool-proof this way — the chance is basically nil that music would have exactly that combination of frequencies, especially if I make it a multi-stage sequence.This is why the telephone engineers picked the specific tones for touch tone signaling. These combinations are not harmonically related, and most speech patterns didn’t contain very much of the tone frequency energy at any given time to generate false positives. Smart dudes at Bell Labs in the 60’s
quote :Breakaway Broadcast indeed has plenty of look-ahead to mute the output. Breakaway Live doesn’t, but who cares — the tones don’t need to be muted in the studio. It’s not like they need to be full amplitude, -40dB down should be plenty strong enough.40dB should be fine if you encode the files to maximize SNR. But in reality how much tone signal time do you need to capture what you need? More than the audio signal latency of BA Live?
Cheers
Sparky
FYI.
Attached are two photos of the MPX composite signal with white noise. The noise was generated using Cool Edit (mono 16-bit 44.1kHz) driving the BBP pipeline.First is the direct composite output (w/ 2 SCA’s unmodulated). The L+R and L-R matrix is clearly visible with the pre-emphasis slope on each. If a BBP user has an o-scope with FFT capability then white noise modulation will aid in showing tilt when using a sound card for MPX generation.
[attachment=1:2ogu8chf]White Noise Modulation Of MPX Composite Signal With SCAs.jpg[/attachment:2ogu8chf]The second photo is the actual RF spectra (no SCA’s). Notice how symmetrical the sidebands are relative to center (the pilot and sideband are the two discrete spikes). This is a properly tuned system that has sufficient bandwidth. Any tuning mismatches will show a noticeable skew in the symmetry. Unfortunately I don’t have anything handy to de-tune it enough to show this.
[attachment=0:2ogu8chf]RF Spectra White Noise Composite Modulation.jpg[/attachment:2ogu8chf][quote author=”Sparky”]Smart dudes at Bell Labs in the 60’s[/quote]
Very very smart. In fact Bell Labs, and later on AT&T, NIST, etc… especially Long Lines stuff… is a particular area of interest of mine from that era. 🙂
[edit]
try this on for size…
JesseG-Weighted Natural Tone Noise.flac
it’s what I would consider to be a natural tone, and it’s roughly the target average signal level for the pre-mastering work I do (and have been getting acclaim from of late).I couldn’t think of a name to call it, so i just made up "JesseG-Weighted" 😛
[/edit]Hey Sparky, that noise ain’t white 🙂
It’s been through pre-emphasis. It might make for a much more even-looking RF spectrum if it was white.
///Leif
quote :I couldn’t think of a name to call it, so i just made up “JesseG-Weighted”Funny
How about shortening it to G-Weighted?quote :It’s been through pre-emphasis. It might make for a much more even-looking RF spectrum if it was white.This would be true if the RF carrier was moduled 100% white w/ no pre-emphasis.
I’m not sure what to call it seeing that it does not fit any of the standard "noise color" definitions.
Closest is violet noise, or differentiated white noise at 6dB per octive.Perhaps we should name it ourselves. How about FM Fuchsia ?
FM Fuchsia, LOL! I like it 🙂.
However, considering that the purpose of the noise is to watch the MPX with a spectrum analyzer, either before or after RF encoding, I think true white noise may be even more useful. 🙂
How about this?
It’s not 100% white, because the noise is going through the highly advanced clippers, but it’s close enough. 🙂
I’ve also implemented the 30hz and 30hz burst, but I believe it would be a bad idea to keep it in. It turns out that an otherwise perfectly calibrated system that shows rock solid 100% with music and regular program material, can show several percent overshoot with the 30hz burst.. A lot of people seem to be confused / perplexed by the necessary calibration already, and I believe that adding this test mode would only make people compromise between optimizing for this non-real-world theoretical test case, and actual program performance. The only time it would work perfectly is with a completely DC straight path from BBP to the exciter, and while that is theoretically achievable, it’s unachievable in practice for the vast majority of BBP users.
These decisions aren’t easy, but sometimes compromises must be made in the name of real-world simplicity.
Another similar compromise I had to make was to clip bass symmetrically even when the user selects asymmetrical clipping — DC straight path is just not something we can count on when using regular sound cards as DACs.
White Noise is a go for the next version, though.
///Leif
Looks really good 😀 😀
However…Plain o’l white noise is great for checking the MPX portion of the airchain. Your MPX tool demonstrates this very well, but once the signal is passed on through to an exciter the ideal world abruptly meets reality. Not all exciters are alike. Each have their strengths and limitations. Many introduce sonic artifacts that can are caused by modulator non linearity, high Q circuits exhibiting group delay, and coupling asymmetry in cascaded amplifier stages. I know many exciter designs use high frequency predistortion techniques that try to compensate for some of the non linearity, but many times it fixes one problem by creating another. Offering both options. i.e White and FM Fuchsia noise spectra will give the user that much better tool set to test their system with (IMHO).
I understand your argument regarding the 30Hz options and I agree in part. Any good designer adheres to the KISS principle (Keep It Super Simple). But the main objective of the 30Hz tool is to see how bad the overshoots really are. Remember this should be an "unprocessed" signal. The 30 Hz tone w/ burst option is to see how the exciter AFC circuits handle this kind of impulse energy. A good way to think of it is testing how well your cars’ suspension responds to an impulse like a deep pot hole. A well designed system that is critically damped the driver hardly notices the bump. Over damped and the driver gets kidney damage. Under damped and the car goes bouncing merrily along for a few km well after the pot hole event (ie. cars with no shocks… just springs
).Exciter PLL control loop filters behave no different. Loop filter dynamics can sonically alter the sound of deep, booty style bass, or heavy bass drum beats. Under damped systems (fast PLL lock times) can create huge RF carrier overshoots that will exceed government regulations, or generate bad asymmetric carrier deviations. Over damped and the base tones get stripped down leaving no low end dynamics. The 30Hz tool is a convenient way to see how your exciter handles such extremes and distortions (if any) it creates. I know many of your customers are or will be future radio pirates that will eagerly embrace BBA as a lower cost way of sounding competitive like their professional FM counterparts. A lot of them will use hand built equipment. Why not give them another tool to help keep the gov radio police at bay? Perhaps as a compromise the 30Hz burst is shaped to help soften the initial overshoot vs. the first 1/2 cycle going right to 100% amplitude. Shaping is more like real world anyway.
Any more thought of using touch tone signal pairs for the preset control mechanism? If you want I could generate a few tone files for you to test FFT processing. Let me know.
Howdy Sparky!
Alright, you’ve convinced me about the 30 Hz. It’s a worst case scenario test, and if your airchain passes that, it will pass anything. I’ll put it in.
However, the pre-emph white noise, I need some more explanation on. 🙂
It’s certainly easier to see whether the response is flat if the noise is white (because it will then show up as flat on the mpx speccy) and it’s also much easier to see asymmetry on the RF speccy (since it’s a nice smooth shape without visible sidebands). Or was it the visible sidebands you were after? Please explain how the fuchsia noise will be useful. Remember it will have much less energy than the white noise, since it still has to stay within +/- 75 kHz to avoid clipping the sound card output (unless you manually increase deviation after the sound card).
I’m convinced about having in-band signalling to switch presets — it’s an excellent idea. I wouldn’t use touch tones specifically — better to do something proprietary and more complicated, that way there’s less change of false triggers. I don’t have the hardware constraints the original DTMF designers had to deal with — I routinely do FFTs with thousands of points in the algorithm already, so I can easily detect a much more complicated (and thus more flexible) signal.
I will definitely implement the signalling it in the future. Just to make it clear, this (and other forms of dayparting) will be in more advanced versions, not in the $199 version. Value for money is already off the charts, so the bar is plenty high enough, I’m drawing the line right here. I’ve gotta make a living, you know 🙂.
Best regards,
///LeifHey, I implemented the pre-emph noise, and the RF didn’t look anything like yours 🙂.
In fact, the only way to make it look remotely like yours was to feed pre-emph white noise into left only (right silent) really quietly, under 15% modulation.
As modulation increases, the sidebands caused by the pilot get completely obscured!
What am I missing? 🙂
///Leif
quote :What am I missing?Actually nothing. I was in error in providing the test conditions 😳 . In efforts to recheck my work I came to realize I inadvertentaly generated a spatial stereo white noise file run through BBP w/ pre-emphasis on.
From the cool edit help files.quote :Spatial Stereo
Cool Edit 2000 generates Spatial Stereo noise by using 3 unique noise sources, and spatially encoding them to appear as if one is coming from the left, the other from the center, and the last from the right. When you listen to it with stereo headphones, your mind perceives sound coming from all around, not just in the center. To choose the distance from center of the left and right noise sources, you can enter a delay value in microseconds. About 900 to 1000 microseconds corresponds to the maximum delay perceivable, and a delay of zero is identical to Mono noise (left and right channels are the same).The settings in my test condition was 500uS.
So me bad… 😳
Looks good though. Makes the sidebands really stand out. 8)quote :Alright, you’ve convinced me about the 30 Hz. It’s a worst case scenario test, and if your airchain passes that, it will pass anything. I’ll put it in.Well perhaps user feedback will decide if it’s work keeping. The DJ crowd might find it useful for locating PA system crash points. Are you planning on shaping the 30Hz burst edges?
quote :However, the pre-emph white noise, I need some more explanation on.I personally like to test things in the way in which they will be used. White noise put through the pre-emphasis process as you pointed out is not "white" anymore, and the energy distribution will be less overall but more concentrated in the upper audio freq regions. Because RF modulator non linearity tends to favor the higher frequency components more so then lower, the pre-emphasied signal makes it easier to locate problems. Taking this further it pushes the RF system bandwidths right out to the edges. Any improperly tuned circuits (filters, interstage coupling, narrow band antennas) will show up a bit more easily vs having uniform noise energy over the whole bandwidth. But again this is a matter of preference. I think for most BBP users plain o’l white will be the most useful. 😉
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