Stereo Tool

I disabled Bass Boost and Loudness. I'm testing the others now...
Yes.
Not what I'm seeing here. I'm lucky to see 30 dB attenuation. Most of the time it's 10-20.
I use 4096 latency, only. Nothing else but 4096.

I'm able to get down into the -100 to -120 range if I go with a -1 dB preamp and some sort of < 0 dB post. That's the only way. If this is "normal" otherwise as far as your design goes or your other customer's desires (or even my lack of understanding), then I guess I need to look into finding another player that can let me stack a 2nd to 4th order highpass in the chain after StereoTool. I've been looking at the Engineers Filter that Bojcha posted, but I don't think that can be used in Winamp.

Edit: I'll try tinkering with negative dB values for pre and post amps tomorrow. It might be workable that way. I am heading for bed now though.

Brian: Post Amp should be <= 0 anyway, otherwise you can get distortion (which gives 'noise' on all frequencies, potentially including bass).

If you ONLY use the bandpass filter, everything else disabled, then something is apparently wrong. Having said that, if you DO enable other filters, you will get some bass.

I now measured it at latency 4096, but the result isn't much better than at 512 - with all filters enabled. Turning Loudness and Bass Boost off does help - without them I'm getting a bass level drop of about 50 dB, with them it's about 20 dB.

Maybe a stupid question, but for what do you need such a steep highpass filter? I usually only use it to protect the filters against very low sounds which can cause distortion - for that it suffices...

I think I might have just found a way to greatly reduce the level of artifacts. This will cause a duplication of the CPU load though... Will check it further for a future version (not for 6.01 anymore - too much work involved).

(Some time ago I wrote that if I had infinite CPU power, I could reduce the latency by half and completely remove artifacts (at the cost of increasing the CPU load by a factor 128 for latency 512, 256 for latency 1024 etc.). This new idea is less spectacular - but it's a step in that direction. And I think if I do it properly I can really reduce the artifact level a lot.)

Another idea is to introduce an intermediate latency between 512 and 1024 - basically by upsampling the incoming audio (say from 48 to 64 kHz) and then processing at at latency 1024 (higher CPU load), or downsampling to 32 kHz and then processing it at latency 512 (lower CPU load).

hans what hardware are you working with?

Also since the whole GPGPU thing is starting to pikc up pace now, do you think it would ever be possible to port the work done by ST to the gpu?
Just an idea, if it is possible I think I'd like to tackle the porting. Gives me something to do xD

_________________
<-- I like this guy!

Completely BETA version for testing. (This is the ST BETA26).

http://www.multiupload.com/5WY78DPWPX

Waiting feedback ...

Enjoy.

I know. Take a copy of my preset that I posted if you want to see the settings.
I'll quadruple check. It's possible that my triple-check last night missed something...
To not have distortion.

I do not know the actual quality of the amp and coil components of my Logitech Z2200's subwoofer. They were routinely listed as a favorite in the 2.1 category, but anyway... The stated bottom end for the sub is 35 Hz. Personally, I'm thinking I'd like to have the signal start dropping significantly at 40. If I go that route with an EQ, especially with the limited number of bands as what you currently have, I'll squash other frequencies that I'd like to not squash...

Again, if this falls outside of your "normal" usage patterns, so be it, and I'll hunt for some other way to do it...

Tested with version 29
In stereotool set to high and then in task manager to realtime. No differences.
Opened a second stereotool window and maximized both windows. Set the new opened window over the other window and moved the taskbar window over it for the redraws. Then still clicks.

Testing with BETA30A
Tested with buffer of 5 ms and moving the window around i get clicks. It looks the same as the other version. Also when setting it to realtime in task manager.

As an aside, the new "idle thread" screen updating isn't to my liking, but my system has far less horsepower than what I've seen most people have, so I realize that I'm the "odd man out"...

I'm on an aging platform. AMD Athlon64 3700+, so single-core. I could get an AGP version of one of the ATI cards with the Stream processors, but I'm unemployed, and that's a hefty investement for still being on a single-core system.

That said, GPU offloading is spectacular. You can have significant performance increases by doing so. OpenCL would be hopefully the direction taken and not CUDA or Stream (CAL / Brook+).

Update to my highpass situation (in new post due to length of time between posts)

Changing around to -4 preamp in Winamp, -1 preamp in StereoTool, and retaining the -0.35 postamp, it seems to be workable. The measurements now are consistently -70 to -90 @ 20 Hz vs. -40 to -60 previously. I might be able to tweak it further. We'll see...

Problem is, so many people have high positive values for preamp in their presets.

Is this really a non-issue? Could be, for everyone but me...but perhaps I'm mistaken about what I want...

The checkbox Use multiple CPU cores for processing if available is helping with reducing clicks so that works a bit. It seems to help more than selecting a different priority. But i also notice differences between Normal and High priority and Real-time. When doing nothing else, selecting Real-time and selecting Use multiple CPU cores is the best for low latencies right now. When doing nothing else and also don't use task manager i can set stereotool maximized with buffer of 1.4 ms without clicks for quite some time.