Best Settings for AHI + AmigaAMP?

[tygre]

Hi all!

I have the latest AHI and AmigaAMP running and they work very well together on my 68060
I'm just wondering what would be the best settings for the two of them to work well and use as less CPU as possible. I read (and use) Thomas' tests but maybe I could further optimise my settings.

For the moment, I set AHI to use Frequency=44100Hz and set AmigaAMP (for MP3) to use:

• Quality=High
• Divide freq.=Auto
• Max. freq.=44100

AmigaAMP uses about 75% of the CPU (very rough estimate!). Would using different values in AHI or AmigaAMP or both keep/increase sound quality while reducing CPU use?

Cheers!

[daxb]

No. If you want to reduce CPU usage then you have to lower sound quality by the AHI settings. Just try for example with different Quality settings or try 22050 frequency instead of 44100. You will here sound quality differences. Feel free to experiment.

AHI has four (0 to 3) units for settings. Usually unit 0 is the default. then you can for example choose unit 1 for high quality and unit 2 for low quality (interesting for games that use AHI).

[tygre]

Thanks Daxb!

Do I understand correctly that for the best sound and least CPU use, the frequencies of both AHI and AmigaAMP should be the same: it's useless to have AmigaAMP at 48000 if AHI is at 22050 and vice-versa?

Cheers!

[daxb]

I don't know how AmigaAMP works. The mpeg settings might just overwrite the AHI settings? However, you can test with equal and different values and listen for quality / compare CPU usage. Or ask the author of AmigaAMP.

[tygre]

Hi Daxb!
Yes, I read Thomas' docs and stuff... I played around but I'm still not sure whether AmigaAMP settings take over AHI settings or vice-versa or both must be the same
Right now, I'm using 44100Hz in both and music plays very well... not sure if I could save some CPU cycles but settings things differently? (Without loosing sound quality!)
Cheers!

[daxb]

I tried it with AmigaAMP 2.25 (old) and settings under Play -> Mpega Layer ... overwrite AHI settings (if not bypassed). You should here the difference when you choose "Divide freq.:" = 1/4 (i.e. 44,1kHz / 4 = 11kHz). Click on Save or Use and reload your MP3 file. If you don't reload the changes will not apply. I use mpega.library as Engine.

I'm quite sure that you cannot save CPU cylces with same or different settings in AmigaAMP and AHI.

[tygre]

Hey Daxb!
In the more recent version, there is no more this setting... only settings related to AHI are about keeping the unit open and swapping channels. It's simpler now

Thanks for your help!
I'll continue playing with the settings but you're right, I'll probably not be able to save much cycles!

Cheers!

[daxb]

But you wrote:

Originally Posted by tygre

For the moment, I set AHI to use Frequency=44100Hz and set AmigaAMP (for MP3) to use:

• Quality=High
• Divide freq.=Auto
• Max. freq.=44100

So, the settings are there (same as in the old version). Maybe the GUI changed but you can still change this settings?

[tygre]

Exactly, that's the source of my confusion
I'll try more later to see if AmigaAMP settings indeed overwrite AHI or not...

[Daedalus]

The main thing here using the CPU is the MPEG decoding, not AHI itself. Regardless of your AHI settings, or even if you're using native Paula output, decoding full quality MP3s will cost you more than half of your CPU time on an '060. To reduce that, you need to downgrade the decoder settings. That will make far more of a difference than changing the AHI settings alone.

[tygre]

Hi Daedalus!

Originally Posted by Daedalus

The main thing here using the CPU is the MPEG decoding, not AHI itself. Regardless of your AHI settings, or even if you're using native Paula output, decoding full quality MP3s will cost you more than half of your CPU time on an '060. To reduce that, you need to downgrade the decoder settings. That will make far more of a difference than changing the AHI settings alone.

Thanks a lot! This makes sense
So I'll leave it at that then, I don't want degraded music

Cheers!

[QuikSanz]

So anyone up for some new " Prisma Megamix "stock?
Can be done for free!

Chris

PS decoding that is...

[Daedalus]

Yeah, I've been waiting for a long time for a new batch of Prisma boards or similar, would even look at building a new device based on the same decoder chip if I had some free time...

[QuikSanz]

I heard " Rumors " of a new batch a while back but, nothing. Too bad, nice bit of kit.

Chris

[klx300r]

@ tygre

I tried every setting possible with latest AmigaAmp and it doesn’t come close to the sound quality that I get from EaglePlayer without playing with settings and using the 14Bit Amplifier plugin using 4 channels at 44336, 1.7 Volume Boost, Mixer at HBoost, Sinc, NoisShape and Surround delay on max.

I don’t have a sound card in my system and the mp3 sound quality is seriously good from my A4000, CS-MKIII, 060@50.

*Only issue I have Eagle Player is I can’t get a list of MP3’s to randomly play songs from the list continuously so if anyone knows please let me know* to

[mfilos]

It works just fine on me mate.
I always had it randomly load modules on start from a big list. So chancing to MP3 files it works as well.
Lemme share some prefs I have:

On Engines I use EMPYGui (for looks) and Playerloader
On Config
--> Preferences: Scroll infos, Save T:, LoadFast, Playerbatch
--> ModulePrefs: LoadDir, Notify, Hide all
--> Program mode: Random module, Songend, Calc duration, Randomstart, Quickstart