does the TI sound more dynamic and lush when in single mode, non usb?

[luddy]

Is there any hard evidence about any of this stuff? For example, has Access ever commented on any of this? As far as I know, they haven't. Or maybe I've missed it ...

You can't conclude much from looking at the number of bits available via at the D/A converters. They obviously are not clocking those converters at 192KHz, so who knows what relevance that figure has to anyone. As for 24 bits, it strikes me as odd that they would send more bits into the D/A converters than they would over the digital connections.

SP/DIF is designed to handle up to 20 bits in an audio stream. I haven't seen any hard evidence about how many of these bits are actually in use -- changing value in a meaningful way -- in the case of the Virus.

I operate on the assumption that the Virus is a 16-bit synth from top to bottom, inside and out. I don't know that to be the case, but I tend to think that if there were really a bunch more bits of precision feeding the converters than are going over the USB or SP/DIF connection, then you would hear a much greater difference in sound for certain patches. There are lots of long tails and other opportunities to pick out 16bits vs 20 or 24bits among the Virus sounds and effects.

I've taken to tracking my Virus digitally -- through SP/DIF -- and then using other D/A converters if I want to bounce the tracks through outboard analog. That's mostly a workflow thing. I have some converters with very low noise floor that I like a little better than the converters on the Virus anyhow.

-Luddy

[marc]

Originally Posted by luddy

Is there any hard evidence about any of this stuff? For example, has Access ever commented on any of this? As far as I know, they haven't. Or maybe I've missed it ...

luddy, i've commented on it in the past, we had this type of thread before. i cannot find my own post anymore but i've posted an easy way for everybody to see if there is a difference. it's based on using the TI as a soundcard, making a sound from the virus going roundtrip into the computer and back to the virus' outs. that you can compare with the outs (and no roundtrip) by switching the part in question to direct mode (or analog out 1+2).

best, marc

[luddy]

Originally Posted by marc

luddy, i've commented on it in the past, we had this type of thread before. i cannot find my own post anymore but i've posted an easy way for everybody to see if there is a difference. it's based on using the TI as a soundcard, making a sound from the virus going roundtrip into the computer and back to the virus' outs. that you can compare with the outs (and no roundtrip) by switching the part in question to direct mode (or analog out 1+2).

best, marc

Nice! Wish I had time to do this test for myself, haha. Hopefully some kind soul who has tried this will report back. Or you could just tell us the punchline! This question actually has a correct and definitive answer from a technical point of view; I'm sure the engineers at Access know whether your round trip test can in principle yield a difference in sound or whether that's impossible on grounds of bit precision...

-Luddy

[DiScO]

I spent a long time playing a 'riff' earlier with the TI in standalone mode. When I was happy with what I was doing I booted up Logic and it all went to sh*t. The power of the same patch just diminished, not to mention of course the feel due to latency, even with the direct outs(as I have found that the majority of the time I have to load the plugin twice to get it tight). I also did a comparison the other day between identical patches on the Ti and the Virus Powercore beta, and the Powercore version wins hands down. And let me tell you, It aint just level. I remember doing the same test some time ago, the powercore version had more 'mid', you could say, although now with the new version I would say the powercore version has more 'depth'. I will have to think again how I work with this machine, as the analogue o/p's are definitely more desirable.

[wehurlbert]

Now let me get this straight - you're comparing the sound from the analog
outputs of the Virus with what you're getting from your soundcard by way
of the Virus USB and your DAW. And you expect them to be the same?

Like Marc said, at the minimum you'd have to use the Virus as your sound
card. And you'll need to be sure you're DAW is not touching the bits - Live
is the only one I've seen make official statements about when they do and
don't touch the bits.

And you'll need knowledge of routing/word-lengths/sample-rates through
the Virus. Marc's statement implies there is equivalence here, but he didn't
specifically say.

Of course, if you have a good sound card, and the differences are gross, you
might be able to make some statements about it. In this case, you shouldn't
be playing while listening. And the performance has to be the same.

You might do this by sequencing a MIDI performance and then recording
audio of that sequence via USB. Now you'd have both a MIDI sequence to
play the Virus (giving you output via Virus analog outs), and a USB audio
recording of the same performance which you'd listen to through your
sound card. Of course, aside from the DAW and the sound card, the word
length and sample rate are variables here. I think this is similar to what
Marc was talking about by using the Virus as your sound card.

Then you could tweak the levels to be equal (yet another variable) and sit
back and listen.

If you've got really good A/D converters, you could record the analog outs
of the Virus back into your DAW, and clinically compare that with the USB
recording i.e. invert phase of one and listen/look. You could also do this
via the S/PDIF out of the Virus i.e. USB vs S/PDIF.

-Wayne

[luddy]

Originally Posted by wehurlbert

Now let me get this straight - you're comparing the sound from the analog
outputs of the Virus with what you're getting from your soundcard by way
of the Virus USB and your DAW. And you expect them to be the same?

Like Marc said, at the minimum you'd have to use the Virus as your sound
card. And you'll need to be sure you're DAW is not touching the bits ...

...

If you've got really good A/D converters, you could record the analog outs
of the Virus back into your DAW, and clinically compare that with the USB
recording i.e. invert phase of one and listen/look. You could also do this
via the S/PDIF out of the Virus i.e. USB vs S/PDIF.

-Wayne

It's not so complicated to compare a couple of sound sources.

There are three minimal signal paths for listening to the Virus, not including the headphone jack:

1. Virus USB -> D/A
2. Virus SP/DIF -> D/A
3. Virus Analog [ -> A/D -> D/A ]

All three of these can be recorded as digital audio (after an optional A/D step in the last case). You can then play them back through a single D/A. You can use a MIDI sequencer to be sure you are getting the same thing all three times. Since you don't care much about the timing in this case, you could probably record all three in one pass if you wanted to. In any case, it's not any harder than recording multiple tracks or takes in a song.

None of the major DAWs changes the bits of a track that is simply recorded as audio and played back at unity gain (and at the original tempo, in the case of Live). Live is the only DAW that silently applies time-stretching to audio (!) so it's the only one where it's really necessary to be so precise about when the warping algorithm is being applied.

In any event, the real question is not better or worse, but rather: are there more bits of precision feeding the internal D/A converters than there are coming over the USB and/or SP/DIF connection? This simple question would be easy for Access to answer, but as far as I know they have chosen to remain silent on the point. Consequently, the only way to get at the answer is to probe with an experiment like the one we're discussing here.

Marc's proposal is nice because it uses a single D/A (in the Virus) for everything. On the other hand, it depends on the return audio path over the Virus's USB link. If that link truncates the audio to 16 bits, then it will give a misleading result -- it removes any extra bits of precision (beyond 16) that the SP/DIF or analog outputs of the Virus may have.

-Luddy

[altunamusic]

Hi guys,

SUper nOOb question here :P

I had Ti for a year, i know how to make sound n design from it. But believe it or not i havent even tried single mode? Can we write midi patern like we use in SEQ mode? and why is it better.. and maybe what is the best routing with Logic pro 8?

I am running on OSX10.5.7, and this 3.0.3 is really a mess in my Logic... I usually can run maximum 8 channel in Seq mode together.. but this time when i ran 2 channels, one of the channel will goes out of tune..

May someone guide me here? *i dont have a sound engineering background*

Thank you.

Din

[TheHobbit]

As said it all depends on what you are comparing it too and usoing in the signals path a way to explain this is thus...

Laymans terms

Using your eyes look at something familiar...a white painted wall.

Now close one eye...does it look any different? (mono - stereo)
Now with both eyes open look at the same wall whilst wearing a set of low end sunglasses (USB lets say)
Now look at the same wall with another a better set of sunglasses (your soundcard).
You are using the same set of eyes and looking at the same wall.
What has changed is the sunglasses and assuming they are different then you would have noticed a variation in 'tone' of the white wall and 'scope' with one or two eyes open.

Analogy explained :

Your eyes = the soundsource (waveform)
The wall = your speakers the end product of what you see
The sunglasses = what ever components are carrying the audio signal from the source to your speakers.

I really must stop visiting forums in the early morning ....

[sdrr00]

Originally Posted by Doc Jones

I believe both the "line input jack" and the "microphone jack" would both qualify as analog inputs. But the problem is these look like unbalanced 1/8th inch jacks whereas the virus has 1/4 inch balanced outputs. So you would be going from two or more 1/4 inch balanced outputs from your virus to only 1 1/8th inch (unbalanced?) input on your soundcard. not quite sure what that would do to your signal. Plus, the cards converters make all the difference in the world and I don't know much about Asus's converters. Just for comparison here is the sound card I am using. As you can see I go directly from balanced 1/4 inch outs (from the virus) to balanced 1/4 inch ins on my card before I hit the converters.

here are the ASUS XONAR D2X sound card converters:

24-bit D-A Converter of Digital Sources: TI Burr-Brown PCM1796 *4 (123dB SNR, Max. 192kHz/24bit).

24-bit A-D Converter for Analog Inputs: Cirrus-Logic CS5381* 1 (120dB SNR, Max. 192kHz/24bit).

from what i read, these are VERY good, so i dont think i will be sacrificing quality. as you can see, the support 192khz/24bit, which is the same as the virus, right? the problem is now whether the unbalanced 1/4" to 1/8" will change or distort the signal in anyway, or will it act as a regular 1/4" to 1/4" balanced input?

the first one is the Digital to Analog convertor.. that would apply to the SDPIF correct? if they are both the same quality coverters, what would be the difference between using either of them