Stereo Tool

It looks like they are all set to bypass.

Hmmm... Well, that's the thing. I've been looking for a waveform writer, but how I've measured my outputs through all sources of media is to record to file with flat PC settings with the audio being played back audibly locally. Then, I pulled the file into Nero Soundtrax.

How did you measure your output? I want to use the same method. Maybe the DSP in my audio card is doing some additional processing that is non desirable?

I cannot measure the output like I could when I worked at a radio station -- we actually could dump to file.

Oh, and I bet I know what you're thinking -- "that audio is very dynamically poor".
Like I said, I worked at a radio station. Dynamically poor is what we know... I've been working on improving dynamic range while keeping the midrange a consistent level - and with aacPlus, intermodulation distortion becomes an issue if you aren't careful with compression timings. Thus, my multiband looks very non-traditional.

Thanks for all your help.

Well, given your method of measuring, the output depends a lot on the sound card that you use.

For example, some time ago I did a measurement with a Creative X-Fi Audio card (at very high frequencies, because Stereo/RDS did not work correctly).

When I sent this to the card:


Measuring it back the same way you describe resulted in:


As you can see, the difference is HUGE. So it's not very surprising that you get overshoots.

Cheaper sound cards such as SoundMAX on-board cards filter out the very low (< 50 Hz) frequencies, and boost the frequencies just above that, which may also cause large changes in the signal.


In Winamp, you can select the Disk Writer output plugin to write to disk instead of playing the audio. I'm not sure about SAM, doesn't it have a similar feature to write the output to a file (might be MP3 encoded, which would not help).

Wow. I'm using an X-Fi, too!

I'll try Winamp with disk writer. Thanks a LOT!

Then, I should be able to do a better instantaneous spectral analysis of the audio to better tweak to what I want it with True RTA.

Much appreciated! Thanks for the great software!

One other things that I noticed when using your settings is that the sound was very "dull" - very little highs. I don't know if that's intentional (might depend on the type of music that you play) - for the tracks that I used for testing it sounded very strange. I don't know if the X-Fi is doing something to the sound which might make it sound ok at your end (The X-Fi claims to make the sound brighter if I recall correctly). You might want to check the sound on some other cards or equipment.

lose the creative card, they ALL suck. m-audio or another high quality card is what you need. creative has been riding their name since the blaster 16 days. pop into some of the audiophile forums and see what they use, tain't creative.
JM2C

Mike

The highs are carefully processed to avoid compression artifacts through the aacPlus CODEC. If you leave them too "shiny", a lot of "garbage" becomes audible at lower bitrates due to the SBR (spectral band replication) process used to reproduce the high frequency spectral content.

I love my Creative card - the primary listening of this stream isn't on my own computer. (Stereo Tool is being used to process Internet radio prior to encoding.)

I like Dolby Digital Live!, and the microphone processor features. Full EAX support is essential on that system. The audio broadcast server is also my primary PC. It is a quad core Intel system with 8GB of RAM. You can guess what I do with it.

Creative is my only solution - forever. I only analyzed the way I did for "overshoots" as I heard the overshoots listening to another device -- but it probably had worse overshooting than the Creative card!

I'm definitely not concerned about audio quality as much as features for an audio card in my computer. I have my audio system for quality.

The Creative X-Fi card doesn't really sound bad (it sounds a lot better than most on-board cards, not that that means a lot as they tend to sound a lot worse than my 20 year old cassette deck) - but you don't get true unmodified sound out of it. For bad quality recordings - and for game processing - it's probably good. Just don't base any conclusions on what you measure with it!

I didn't realize that AAC uses this spectral stuff - that can really get bad if you have a lot of highs...

About the overshoots that you hear: They are PROBABLY caused by the AAC encoding (especially when you use this spectral stuff!) - so lower the Post Amp to (with the spectral thingy) 0.60 or so. (128 kbit/s MP3 already needs 0.80, without spectral analysis and regeneration).

Greetings

I have a Creative X-fi elite pro and have been veyr happy with it.

In conjunction with SAM I use kernal output streaming and an accPlus audio streaming at 128 and of course together with StereoTool.

I am curious how you have your X-fi setup in regards to

1. 3D
2. crystalizer
3. SVM
4. equalizer

all of these make quite a difference particularly if using the kernal output.

1. Disabled
2. Disabled
3. Disabled
4. Flat and Off

aacPlus and MP3 Pro both use SBR actually.

As far as "low", I'm talking around the realm of 32kbps, not 128kbps.

Ok... so that looks like it was my problem. I installed Winamp, and used Disk Writer and...


My processing is the top set of waveforms, unprocessed (other than through mastering) is at the bottom.

This is such an incredible piece of software. Thanks a lot hvz!!! As you can tell -- I definitely "mowed the lawn" (which is my audio ). Meh, it's radio.

I almost feel like I'm using an Omnia-6FM again, but... without the stupidness! (Though, my highs did sound like I was using an Optimod)

I changed my settings to help with HF content, and I backed the post-amp gain down to 0.60. Here are the updated settings; I'm not too much of a fan of the "watery cymbals" that it causes by having the HF content prevalent, but I'll get used to it I'm sure.

[Common]
Pre amplifier=4
Post amplifier=0.600000024
Extra loudness=1
Hard limit output=1
Downsample very high input sample rates to near 44.1 kHz=1
Mode=Advanced
[Noise Gate]
Enabled=1
Difference=0
Noise level=1.5
[Singleband Compressor]
Enabled=0
Difference=0
Maximum volume=10
Maximum value=32767
Attack speed=0.999998987
Decay speed=0.999000013
Above Top Limiter=1
[Pre Compressor]
Enabled=1
Difference=0
Delay enabled=0
Maximum volume - Band 1=25000
Maximum volume - Band 2=15000
Attack speed - Band 1=0.000003152
Attack speed - Band 2=0.000002737
Decay speed - Band 1=0.040594164
Decay speed - Band 2=0.026004046
[Multiband Compressor]
Enabled=1
Difference=0
Delay enabled=0
Very high quality enabled=1
Maximum volume - Band -1=7200
Maximum volume - Band 0=8310
Maximum volume - Band 1=8810
Maximum volume - Band 2=7630
Maximum volume - Band 3=5930
Maximum volume - Band 4=3730
Maximum volume - Band 5=2750
Maximum volume - Band 6=3500
Maximum volume - Band 7=4600
Maximum volume - Band 8=2500
Attack speeds linked=0
Attack speed - Band -1=0.000002737
Attack speed - Band 0=0.000002737
Attack speed - Band 1=0.000015691
Attack speed - Band 2=0.000015691
Attack speed - Band 3=0.000015691
Attack speed - Band 4=0.000015691
Attack speed - Band 5=0.000015691
Attack speed - Band 6=0.000132422
Attack speed - Band 7=0.000132422
Attack speed - Band 8=0.000132422
Decay speeds linked=0
Decay speed - Band -1=0.001828427
Decay speed - Band 0=0.001828427
Decay speed - Band 1=0.000139355
Decay speed - Band 2=0.000139355
Decay speed - Band 3=0.000139355
Decay speed - Band 4=0.000139355
Decay speed - Band 5=0.000139355
Decay speed - Band 6=0.000139355
Decay speed - Band 7=0.000139355
Decay speed - Band 8=0.000139355
Above Top Limiter=1
Clipping enabled=1
Postprocessing enabled=1
Relative clip position - Band -1=1.500000238
Relative clip position - Band 0=1.500000238
Relative clip position - Band 1=2.508771658
Relative clip position - Band 2=2.508771658
Relative clip position - Band 3=1.500000238
Relative clip position - Band 4=1
Relative clip position - Band 5=1
Relative clip position - Band 6=-1
Relative clip position - Band 7=-1
Relative clip position - Band 8=-1
Final limiter value=0.306499988
Final limiter decay speed=0
Final limiter clipping=0.600000024
Equalizer enabled=1
Equalize before multiband-compression=1
Equalizer position - Band -1=2.508771658
Equalizer position - Band 0=2.508771658
Equalizer position - Band 1=1.857142687
Equalizer position - Band 2=1.857142687
Equalizer position - Band 3=1.702702761
Equalizer position - Band 4=1.105262995
Equalizer position - Band 5=0.709401608
Equalizer position - Band 6=0.709401608
Equalizer position - Band 7=0.550387621
Equalizer position - Band 8=0.459854007
[Stereo]
Enabled=1
Delay enabled=0
Difference=0
Center bass=1
AZIMUTH limit=60.979999542
AZIMUTH change speed=0.200000003
Image phase amplifier=1.399999976
Image phase amplifier maximum angle=130.5
Image phase amplifier maximum separation strength=65.849998474
Image width amplifier=1.200000048
Extra phase shift=0
Mono or stereo only=-0.659999967
[Channel Delay]
Enabled=0
Left Delay=0
[Output Filter]
Enabled=1
Lowpass filter=15000
[Final Pre-Limiter]
Enabled=1
Difference=0
Pre-amp=1.708543897
Response time=0.400000006
[Final Limiter]
Enabled=1
Difference=0
Pre-amp=1.330095887
Response time=0.0125
[FM Transmitter]
Enabled=0
Pre-emphasize=0
Pre-emphasis time=50
Output is pre-emphasized=0
Stereo encoder enabled=0
RDS encoder enabled=0
RDS PS text=2s:STEREO/2s:TOOL/<1=1.5s,2..-2=2t,-1=1.5s:WWW.STEREOTOOL.COM
RDS RadioText text=60s:Stereo Tool: Professional Audio Processing - http://www.stereotool.com/30s:Stereo Tool by Hans van Zutphen, 1999-2008 - http://www.stereotool.com
RDS PTY=0
RDS PI=65535
RDS Alternative frequency 1=0
RDS Alternative frequency 2=0
RDS Alternative frequency 3=0
RDS Alternative frequency 4=0
RDS Alternative frequency 5=0
RDS Alternative frequency 6=0
RDS Alternative frequency 7=0
RDS Alternative frequency 8=0
RDS Alternative frequency 9=0
RDS Alternative frequency 10=0
RDS Alternative frequency 11=0
RDS Alternative frequency 12=0
RDS Alternative frequency 13=0
RDS Alternative frequency 14=0
RDS Alternative frequency 15=0
RDS Alternative frequency 16=0
RDS Alternative frequency 17=0
RDS Alternative frequency 18=0
RDS Alternative frequency 19=0
RDS Alternative frequency 20=0
RDS Alternative frequency 21=0
RDS Alternative frequency 22=0
RDS Alternative frequency 23=0
RDS Alternative frequency 24=0
RDS Alternative frequency 25=0
RDS TP=0
RDS TA=0
RDS Music=1
RDS Artificial Head=0
RDS Compressed=1
RDS Dynamic PTY=0
RDS RadioText Enabled=1
RDS ClockTime Enabled=1
[Direct soundcard access]
Enabled=0
Device ID=
Volume=1
Buffer size=1
Send to Winamp=Nothing
[Low latency output]
Enabled=0
Device ID=
Volume=1
Buffer size=0.079999998

I figured out something cool to do - "top-down" processing - I was wondering where the "gated limiter" was. It turns out, I wasn't using "Clipping" properly. It's like using an OptiMod, but not!

I can use the multiband limiters on the low frequency content only, but avoid using them on the high frequency content. Then, I can compress the high frequency content just enough to make it avoid hitting the hard limiting at the output. Thus, I am avoiding intermodulation distortion in the SBR area of the aacPlus CODEC. Furthermore, I noticed there is no discernible difference running the output at 0.6, 0.8, or 0.95 in terms of noticeable artifacting, so I have decided to run it at 0.95 to optimize listener volume.

Thanks, hvz!

I am effectively normalizing the audio, while maintaining "kick" in the snare, and I can handle "hypercompressed" content just fine. I think people will like the "new" sound of my stream. I even figured out how to moderately de-ess too (using one limiter ("Clipping") on one high frequency band). I'm sure it is still a work in progress.


There is much more treble with this preset:

[Common]
Pre amplifier=3.5
Post amplifier=0.949999988
Extra loudness=1
Hard limit output=1
Downsample very high input sample rates to near 44.1 kHz=1
Mode=Advanced
[Noise Gate]
Enabled=1
Difference=0
Noise level=2
[Singleband Compressor]
Enabled=0
Difference=0
Maximum volume=10
Maximum value=32767
Attack speed=0.999998987
Decay speed=0.999000013
Above Top Limiter=1
[Pre Compressor]
Enabled=1
Difference=0
Delay enabled=0
Maximum volume - Band 1=40500
Maximum volume - Band 2=22500
Attack speed - Band 1=0.000003152
Attack speed - Band 2=0.000002737
Decay speed - Band 1=0.010666901
Decay speed - Band 2=0.010666901
[Multiband Compressor]
Enabled=1
Difference=0
Delay enabled=0
Very high quality enabled=1
Maximum volume - Band -1=6950
Maximum volume - Band 0=7000
Maximum volume - Band 1=4850
Maximum volume - Band 2=4600
Maximum volume - Band 3=3650
Maximum volume - Band 4=2750
Maximum volume - Band 5=2000
Maximum volume - Band 6=2800
Maximum volume - Band 7=3000
Maximum volume - Band 8=2300
Attack speeds linked=1
Attack speed - Band -1=0.000055309
Attack speed - Band 0=0.000055309
Attack speed - Band 1=0.000055309
Attack speed - Band 2=0.000055309
Attack speed - Band 3=0.000055309
Attack speed - Band 4=0.000055309
Attack speed - Band 5=0.000055309
Attack speed - Band 6=0.000055309
Attack speed - Band 7=0.000055309
Attack speed - Band 8=0.000055309
Decay speeds linked=1
Decay speed - Band -1=0.000043197
Decay speed - Band 0=0.000043197
Decay speed - Band 1=0.000043197
Decay speed - Band 2=0.000043197
Decay speed - Band 3=0.000043197
Decay speed - Band 4=0.000043197
Decay speed - Band 5=0.000043197
Decay speed - Band 6=0.000043197
Decay speed - Band 7=0.000043197
Decay speed - Band 8=0.000043197
Above Top Limiter=1
Clipping enabled=1
Postprocessing enabled=1
Relative clip position - Band -1=1.352941036
Relative clip position - Band 0=1.352941036
Relative clip position - Band 1=1.150537729
Relative clip position - Band 2=1.150537729
Relative clip position - Band 3=1.352941036
Relative clip position - Band 4=-1
Relative clip position - Band 5=-1
Relative clip position - Band 6=-1
Relative clip position - Band 7=0.600000024
Relative clip position - Band 8=-1
Final limiter value=0.451599985
Final limiter decay speed=0
Final limiter clipping=0.85185194
Equalizer enabled=1
Equalize before multiband-compression=1
Equalizer position - Band -1=3
Equalizer position - Band 0=2.333333254
Equalizer position - Band 1=1.500000238
Equalizer position - Band 2=1.500000238
Equalizer position - Band 3=1.409638405
Equalizer position - Band 4=1
Equalizer position - Band 5=0.801801801
Equalizer position - Band 6=0.801801801
Equalizer position - Band 7=0.754385948
Equalizer position - Band 8=0.754385948
[Stereo]
Enabled=1
Delay enabled=0
Difference=0
Center bass=1
AZIMUTH limit=60.979999542
AZIMUTH change speed=0.200000003
Image phase amplifier=1.5
Image phase amplifier maximum angle=130.5
Image phase amplifier maximum separation strength=65.849998474
Image width amplifier=1.200000048
Extra phase shift=0
Mono or stereo only=-0.600000024
[Channel Delay]
Enabled=0
Left Delay=0
[Output Filter]
Enabled=1
Lowpass filter=15600
[Final Pre-Limiter]
Enabled=1
Difference=0
Pre-amp=1.089536071
Response time=0.400000006
[Final Limiter]
Enabled=1
Difference=0
Pre-amp=1.182783961
Response time=0.0125
[FM Transmitter]
Enabled=0
Pre-emphasize=0
Pre-emphasis time=50
Output is pre-emphasized=0
Stereo encoder enabled=0
RDS encoder enabled=0
RDS PS text=2s:STEREO/2s:TOOL/<1=1.5s,2..-2=2t,-1=1.5s:WWW.STEREOTOOL.COM
RDS RadioText text=60s:Stereo Tool: Professional Audio Processing - http://www.stereotool.com/30s:Stereo Tool by Hans van Zutphen, 1999-2008 - http://www.stereotool.com
RDS PTY=0
RDS PI=65535
RDS Alternative frequency 1=0
RDS Alternative frequency 2=0
RDS Alternative frequency 3=0
RDS Alternative frequency 4=0
RDS Alternative frequency 5=0
RDS Alternative frequency 6=0
RDS Alternative frequency 7=0
RDS Alternative frequency 8=0
RDS Alternative frequency 9=0
RDS Alternative frequency 10=0
RDS Alternative frequency 11=0
RDS Alternative frequency 12=0
RDS Alternative frequency 13=0
RDS Alternative frequency 14=0
RDS Alternative frequency 15=0
RDS Alternative frequency 16=0
RDS Alternative frequency 17=0
RDS Alternative frequency 18=0
RDS Alternative frequency 19=0
RDS Alternative frequency 20=0
RDS Alternative frequency 21=0
RDS Alternative frequency 22=0
RDS Alternative frequency 23=0
RDS Alternative frequency 24=0
RDS Alternative frequency 25=0
RDS TP=0
RDS TA=0
RDS Music=1
RDS Artificial Head=0
RDS Compressed=1
RDS Dynamic PTY=0
RDS RadioText Enabled=1
RDS ClockTime Enabled=1
[Direct soundcard access]
Enabled=0
Device ID=
Volume=1
Buffer size=1
Send to Winamp=Nothing
[Low latency output]
Enabled=0
Device ID=
Volume=1
Buffer size=0.079999998