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Hi Dax!
I know exactly what you mean.
Breakaway FM does not have a stereo enhancer — but it does have plug-in support!
So, you can load any stereo enhancer you like. If you use the Winamp DSP->VST wrapper, you can even load VST plug-ins, such as Spartacus.
///Leif
Hi lpy!
When you select 15us pre-emphasis, and check the de-emphasis box, you’re getting flat frequency response. The only difference is that the clipper won’t allow treble near the edges of the waveform. 15us pre-emphasis is so benign that it has no audible drawbacks at all, only advantages (less clipping).
The low pass filter is a different story. The honest answer is, I plan to release a mastering version of my clipper some day, and it won’t be $199. The 16 kHz low pass is basically the only thing keeping BaFM out of the hands of mastering engineers, and they’d kill for an algorithm like this for mastering 😉.
FM can actually do 18 kHz with filters as sharp as mine, and still have a full kHz of 60dB pilot protection contour(referenced to 8% pilot injection).
I personally hear up to 17.5 kHz, but really, I’m completely happy with 16 kHz, because it’s really flat all the way up to 16, with a sharp cutoff thereafter.
For comparison, when you ask the LAME mp3 encoder for 16000hz low pass, you get a transition band between 15677 and 16258 hz, thus the frequency response is really only flat up to 15.6 kHz. This does make an audible difference to me — the difference between 15.5 and 16 is much bigger than the difference between 16 and 17 for me personally.
You’re being too picky
.///Leif
We never actually got VL into an actual iPod, there was no sense in spending the engineering resources without the business issues taken care of.
Rockbox would be possible from an engineering standpoint, but doesn’t make much sense from a business standpoint.
iPhone / iPod Touch would be great though! If the api makes it possible, we will definitely look into it.
///Leif
Hi lpy!
Indeed that’s not clipping. MP3 encoders usually use a much higher threshold above 16 kHz to determine what to keep or throw away, resulting in only brief transients remaining above 16k. Indeed it happens at higher bitrates too, although less pronounced. It also depends on what encoder you use — some do it more, some less.
///Leif
Dj Buik, it might.
The breakaway core algorithm itself is highly optimized, and can be slimmed down further to fit inside a smaller space, with minimal audio impact. Also many things that are part of Breakaway Personal (such as adaptive sample rate converters, ocilloscopes) can be omitted for a phone implementation.
///Leif
Hi Dax!
RadioSeven uses an older algorithm (equivalent to Volume Logic), it’s about three generations behind now. Breakaway FM sounds significant cleaner at the same loudness level.
Nevertheless, I’ve listened to R7 and set up my own 128k MP3 stream with Breakaway FM to compare.
Try the following settings:
Plutonium – 15us Pre-emphasis + De-emphasis
Final Drive: -1.5dB
Range: 50
Power: 65
Speed: 55
Bass Cut: -10
Bass Shape: 0This is very close to their sound, except BaFM has cleaner transients and less IM distortion 🙂.
Best regards,
///LeifHi Stuart!
There was indeed a well hidden easter egg in VL for windows that allowed this (although it was never ported to the mac).
We will probably hade a more advanced version in the future (at a more reasonable price for an audio processor of this caliber), but simplifying controls was one of the compromises we had to make to be able to sell Breakaway Personal at $29.95 while maintaining full sound quality.
There are downward expanders, they’re used by certain presets. Next release (coming very shortly) will have more presets that enable them.
Breakaway in the iPhone would be incredible! We’ll see what happens 😉.
Best regards,
///LeifLivelike, thank you! Always happy to help, and audio processing is of course my favourite conversation subject 😉.
Funny though, I just noticed the following:
[quote author=”Lane”]Just a quick question that I hope doesn’t have a long and complicated answer.[/quote]
Oops 🙂.
///Leif
Hi Lane!
DrShane is right — you have to keep de-emphasis on for the L/R output (unless you’re using the built in plug-in support. Plug-ins always receive de-
emph no matter how you set the L/R out switch.)Pre-emphasis doesn’t have anything to do with loudness though, other than hampering it 🙂.
Pre-emphasis is used on FM for noise reduction reasons. Boost treble (before the transmitter), add noise (in the air), reduce treble (inside the radio), and the audio comes out normal but the noise gets suppressed by the treble reduction.For webcasting though, I’m using it for an entirely different reason. Explaining it requires looking at what happens when you MP3-encode a tightly peak controlled signal.
Breakaway FM has excellent peak control. It really packs the waveform solid, by way of clipping, but it uses a highly advanced clipper that cancels out distortion more effectively than any other before. This means, that even though the output waveform (Amsterdam Preset) looks like this:
Even though it’s obviously clipping pretty much all the time, there’s no audible distortion. It sounds pristinely clean.
The source material here was 10 seconds from the intro of "Sleeping satellite" by Tasmin Archer. The intro is acoustic guitar, synthesizers, and a very bright and sibilant voice. Sibilance (S-sounds) are usually the first thing to distort when clipping.
Here’s a spectral analysis of the above waveform:
Breakaway FM, while controlling peaks, ALSO controls the output bandwidth. You can see here that it’s strictly bandwidth-limited to 16 KHz.
Now, let’s see what happens when this goes through an MP3 encoder at 128 KBps.
See all those overshoots? It happens because of the frequency components thrown away by the MP3 encoder to meet the bitrate quota. If those frequency components happened to be harmonics keeping the peak level down, overshoots will result.
In all the examples here, I’ve used a reference level of -3dB. This means there’s headroom. Normally, when you’re doing web radio, you’re pushing 0dB, meaning there is no headroom for MP3 overshoots. Attenuating several dB’s defeats the purpose of clipping in the first place.
So, what happens when these overshoots (everything above the white lines) are chopped off by the protection clipper in the MP3 decoder?
Flat (no pre/de-emphasis)See all those spikes in the spectrum? That’s distortion. Don’t be fooled by the fact that we only really see them in the black area, they go all the way through to the bottom. They’re usually masked by the audio, but not always! S-sounds, in particular, get really nasty sounding (like a worn stylus on a turntable, only worse).
Here’s the flat spectrum with embedded lyrics, so you can see what to look for above.
The reason S sounds are so critical, is that they have all their energy in a narrow frequency band, and the more distortion is added, the more it sounds like an F. (This is similar to why it’s impossible to tell S and F sounds apart over the phone. With the telephone network’s 3.5 KHz low pass filter, these two sounds have identical spectrum. But, I digress.)
So, to compensate for this, I came up with the idea to use pre-emphasis to my advantage. Pre-emphasis to 15 or 25us barely affects loudness or treble content audibly, but it pulls the treble away from the edges of the waveform, where it would be causing clipping in the MP3 decoder.
15us pre/de-emphasisA lot of spikes have gone, but a few new ones have even appeared. The important thing though is that there are no spikes on S-sounds anymore. Those were the most important ones — the other ones are much less audible.
25us pre/de-emphasisHere, almost no extra clipping happens. 25us pre-emphasis does audibly reduce treble content on some program material, but it’s real subtle — if I was doing a 128kbps stream or below, I would use 25us pre-emphasis.
If i had 192kbps, I would use 15us.
Wow, this took a while! Don’t worry – I can use this for the manual. 😉
Best regards,
///LeifHi Mike!
Breakaway does not run on Microsoft (Windows CE) handheld devices – the current version runs on Windows XP / Vista / 2000 desktop PCs.
We would certainly love to get into one particular handheld device, though. That device, is the iPod! 😉
///Leif
Hi Adam!
I’m not sure there is such a thing as completely vista ready — not if the term "vista" in that statement includes every computer that happens to be running vista, whichever arbitrary latency-unfriendly software happens to be installed. 🙂
I’ve been able to get acceptable latency and very high stability on clean Vista 32 and Vista 64 systems — but I installed Vista myself, did not use a factory preinstalled version.
The latency check tool lpy linked to earlier seems to be a very useful tool, did you try to run it? What latency values do you get?
Maybe it could help in determining what driver / software is actually causing the problem, which would be a better solution — then we’d know more clearly what was causing it, so you wouldn’t have to reinstall the whole system.
///Leif
I feel your pain. Vista is the bane of my existence as a developer!
What audio interface is actually in use? Kernel Streaming (KS), DirectSound (DS) or Wave?
It may be worth looking in the expert settings and changing to a different interface.
///Leif
Hi Mom! 🙂
Fancy meeting you here. 🙂
I think the easiest solution is to run the Breakaway installer again. I’m not sure why the automatic update affected the start-up of breakaway, but running the Breakaway installer again should do the trick.
Best regards,
///LeifHi lpy!
Vac 3.x does not support Kernel Streaming — it is a native Wave driver.
If you look in the drop-down to the left of the sound card name, where it currently says KS.. Select Wave instead, and you will see Vac in the list.
Yes, the 16 kHz bandwidth is a brick-wall lowpass. However, this is actually a good thing even for webcasting, because frequencies higher than 16 KHz are usually encoded with lower resolution, and would cause more overshoots, which would cause distortion in the decoder when you start with a tightly controlled, processed signal like what Breakaway FM generates.
///Leif
