Fixed Integer Playback

[Panelhead]

When Pure Music 1.8 is released, many here will have the option of Fixed Integer playback. This seems to be a good option.

I saw the short list of dacs known to have Fixed Integer capability. Is there a test or way to check dacs not on the listing?

I see where dacs with CEntrance USB usually have this feature. How about CEntrance FireWire? Is a CEntrance designed interface a key?

 

George

 

 

[MarkS]

In addition, if someone could give a quick explanation of what this is and why it should be a benefit, that would be great. I did some searches but can't seem to find anything truly on point.

 

[wgscott]

Audirvana hasthe ability to check and report back to the user (as well as to use it).

 

The idea, from my limited understanding, is that your mac will convert 24 bit to 32 bit float by default, to create space for mixing in of audio from several inputs simultaneously, for using core audio filters, equalization, volume gain control, etc. If a piece of software operates in hog mode and no other audio output is sent to the device, and you do nothing to alter he bit perfect stream, there is no need to convert from 24 bit to 32 bit and then back. Integer playback in hog mode thus skips two computational steps, so the data path becomes the shortest "distance between two points.". The hope is that this improves sound quality.

 

Damien worked hard implementing this in Audirvana. I guess now the payware people see themselves being left behnd the free alternative.

 

[jdubs]

Where is the "short list" located? I want check on my Metric Halo LIO-8.

 

Jim

 

[Panelhead]

Look at the Pure Music 1.8 thread. I really hope that is a very incomplete listing. None of mine are on it.

Maybe I need to drop more than 500.00 on a dac.

 

George

 

[ted_b]

tested it.

 

If you have access to MAc's HAllab application then you can test to see if your DAC can live in a non-mixed integer stream.

 

1. Run HALLab without any other player running

 

2. Important! Press the Take button in the Info tab. The Hog mode should change from -1 to another positive number (which happens to be the process ID of the application owning Hog mode; here, HALLab).

 

The second step is important because the non-mixable integer streams aren't revealed unless we have taken Hog mode.

 

3. Check for the presence of Unmixable signed integer output stream formats in the Streams tab.

 

4. Even more important!!!!!!! If you change the stream formats in the Streams tab, change them back to the originals before quitting HALLab, or unpleasant things can happen.

 

Keep in mind you are mucking with the innards of the audio system here. Accordingly, proceed with caution.

 

But if there are no unmixable streams, which appears the case with many DACs, then you can't take advantage of integer support. I've yet to find a firewire DAC, for example, that works with integer support.

 

 

 

What is integer support? it is the ability to bypass the Mac's core audio 32 floating point conversion and use direct integer conversion. The result is a cleaner reproduction with lower noise floor and more dynamics. I've heard the beta. It's very nice. As stated earlier, it works with Antelope DACs.

 

By the way, I've noticed that those DACs who support integer playback are darn similar to the list of DACs that are compatible with Linux in USB Class 2 Audio. Not sure if it's a coincidence, but here's THAT list:

http://www.sonore.us/Sonore-USB-Compatibility.html

 

Ted

 

 

[losingmyreligion]

 

"Damien worked hard implementing this in Audirvana. I guess now the payware people see themselves being left behnd the free alternative."

 

 

Ayrewave, now Decibel, was the first OS X based application to offer Integer mode publicly.

 

Anyone who has implemented it has probably worked hard on it. E.g., it was mentioned as available in an upcoming release of Pure Music for several months.

 

 

 

 

 

 

 

[Panelhead]

I know the future of connections is USB. But I find it hard to swallow that nine of the FireWire dacs are capable of Fixed Integer Processing.

This lowers my value of the PM 1.8. I still can only copy the redbook layer of my SACD's. And I need to find another dac to use the Fixed Integer function.

Course, this is a free upgrade. So I am still getting way more than I am paying for.

 

George

 

[wgscott]

I've read your post several times and am at a total loss for what point, if any, you are attempting to make. Perhaps I've given it more thought than went into it?

 

[losingmyreligion]

you've got PM

 

[wgscott]

You've got PMS.

 

My point was to disabuse you of the (incorrect) notion that the "payware people" (as you call them) see themselves "being left behnd (sic) the free alternative".

 

Stephen Booth delivered Integer Mode prior to Audirvana's initial release, and Rob Robinson was certainly planning to, as it was reported to be available in an upcoming release months prior to it's release by Damien.

 

[jdubs]

From MH, regarding the LIO-8:

 

"We are currently investigating the prospect of implementing a fixed integer playback mode.

 

While our driver does not support fixed integer playback at this time, we have verified that the process of going from INT to float, to our driver and back to INT is 100% bit clean."

 

Owners of this DAC should definitley shoot them a note to let them know there is a lot of interest for this feature.

 

-Jim

 

 

 

[Panelhead]

Does that MH does not think INT straight through will be an improvement? Since the MH gear is assync FW there be no correlation like USB. Seems most assync USB dacs are capable of running Fixed Integer.

 

George

 

[ted_b]

of integer playback (nor was it Linux compatible). My Antelope Gold is (on both counts).

 

[Mercman]

Channel D had integer working a long time ago. They cannot release beta software since there are expectations from the paying customers. Damien on the other hand can release his betas since no one is paying for this other than donations.

 

I agree with wgscott that Damien has done a great deal of work. I have listened extensively to both the PM integer beta and Audirvana and have definite opinions on the sound quality of these programs. I am going to wait until PM releases 1.8 before I comment.

 

As for the Firewire guys, from their persepctive all of this fuss about integer is silly. The only problem is that integer makes a big difference.

 

[MarkS]

I am a PM loyalist, but this thread got me interested in what integer playback can do, so I downloaded and tried Audirvana for the first time today. All I can say is that if integer playback is what is going on with Audirnava then I am REALLY REALLY excited about PM 1.8. Audirvana had a warmth and naturalness that I did not really know I was missing using PM. To me, it sounded more analog than what I had previously heard on my system running PM.

 

That said, I still think PM is an excellent player. Additionally, Audirvana was extremely buggy for me, crashed frequently, and often created an audible right channel crackle and hiss. PM has been rock solid for me for several builds now. Further, while this is most certainly personal, I vastly prefer PM's integration with iTunes to the UI implemented in Audirvana. However, folks who haven't tried Audirvana yet should certainly give it a try.

 

I really can't wait to hear PM 1.8!!

 

[agentsmith]

How does one test if integer mode is working with Audirvana?

 

Can someone tell me if dCS Debussy supports integer mode?

 

[seta]

dCS Debussy supports Integer.

See last twenty replies or so of this thread.

 

[driven -- by sound]

Yes, dCS Debussy supports integer mode. To check, make sure you select "Hog Mode" & "Integer mode" in Audirvana preferences.

 

Then select/play a track, go to "Debug" under file options (Audirvana)and click. If you only see "32 bit Mixable streams" displayed, no integer mode support.

 

If you see "non-mixable streams" displayed, you have support. See example below for DAC QB-9:

 

Here's confirming that the Ayre QB9 works

 

Audirvana rev. 0.9.1 debug information:

 

Currently playing in Integer Mode:

Non-mixable linear PCM Interleaved 24bits little endian Signed Integer aligned low in 32bit, 8 bytes per frame @44.1kHz

 

Hog Mode is on

Devices found : 2

 

List of devices:

Device #0: ID 0x104 Built-in Output UID:AppleHDAEngineOutput:8,0,1,1:0

Device #1: ID 0x106 Ayre USB Interface UID:AppleUSBAudioEngine:Ayre Acoustics:Ayre USB Interface:Streamlength™:1

 

Selected device:

ID 0x106 Ayre USB Interface UID:AppleUSBAudioEngine:Ayre Acoustics:Ayre USB Interface:Streamlength™:1

6 available sample rates up to 192000.0Hz

44100.0

48000.0

88200.0

96000.0

176400.0

192000.0

 

[agentsmith]

Sorry I am thick.

 

I will try tonight when I go home, excited for another thing to play with

 

[MarkS]

It is very easy to set up with the Debussy.

 

[agentsmith]

Yes the Debussy really is a joy to use.

 

[agentsmith]

Just want to thank everyone's direction. Just checked and my Audirvana is already happily playing in integer mode. Sounding glorious music tonight by way of Makoto Ozone's piano.

 

[Jud]

mercman writes:

 

The only problem is that integer makes a big difference.

 

IIRC, you commented in another thread that the 32-bit float processing was not computationally "expensive," leading me to think perhaps it wouldn't make much difference sonically. If it's correct that 32-bit float isn't materially more CPU-intensive than integer mode, can you say in summary fashion (for us non-engineers:) what accounts for the big difference in sound?

 

[Akapod]

iTunes outputs at 24-bits, despite the fact that the vast majority of the music is at 16-bit. My understanding is that Apple just adds a bunch of zeros to the 16-bit signal, which doesn't change it sonically at all.

 

Would making a 32-bit signal just involve adding eight more zeros, and then deleting them on the other side?