Sound Card / Audio Interface with VT[5]

[kevpatt]

Hi,

I am wondering if there is any way to use a (non-NewTek) sound card or external audio interface with VT[5]. We have the SX-84 breakout box but the audio I/O quality leaves something to be desired, IMHO.

I would like to use a dedicated piece of audio hardware to bring audio in and out of VT[5]. Like a MOTU 896, for instance.

Is there any way to get these audio sources to show up on the VT[5] audio mixer? Or otherwise get the audio into VT[5]?

Thanks,

Kevin

[Quiet1onTheSet]

Hi,

I am wondering if there is any way to use a (non-NewTek) sound card or external audio interface with VT[5]. We have the SX-84 breakout box but the audio I/O quality leaves something to be desired, IMHO.
Kevin

What kind of audio artifacts are you discerning?

Are you employing proper techniques for driving the VT's virtual audio mixing console with proper gain structure?

That is, ensuring first, that the TRIM knob for each source coming into the SX-8 is set optimally (adequate signal on the channel strip's meter, with no clipping, while that channel strip's volume fader is at the dark line (Unity gain, which is about 3/4 up the length of the fader path)?

Also, is the virtual audio mixer's master output fader positioned at UNITY gain as well?

Even before checking for those, you ought to ensure that you double-click on the "speaker icon" on your Windows task tray, so as to effect a resetting of the selected soundcard's input and output audio faders -- again, so you have unity gain throughout the audio signal path.

That besides, please explain in detail, the type of "noise" you're hearing, and which Toaster card are you using, and which Toaster software are you running. Is it VT[4] perhaps, with the older VT[2] or VT[3] card, or what?

Would love to hear more from you on this, so others might be inclined to chime in to help.

[kevpatt]

Let's just say the VT audio hardware is not the quietest I've heard. There is a surprising amount of digital noise / hiss on the inputs (and outputs), even when properly trimmed, even when left unconnected. This raises the system noise floor and reduces the dynamic range.

The hardware is a card that came with the VT[4] 4.6, which was recently software upgraded to VT[5]. This noise has always been present. It is low enough not to be a serious problem, but high enough to aggravate me.

We also have another VT[4] 4.6 system and it is exactly the same. I can assure you that the inputs are properly trimmed, gains all set to unity, connected to equipment with the proper matching impedance. (Equipment that is perfectly quiet on any other mixer's inputs.) Levels are fine.

I am convinced that this is a design issue. The noise seems to be digital in nature. The SX-84 brings analog audio in and out of the VT[5] card which is inside the computer's case, a very electrically noisy environment. This is of course handled on the very same PCI card that performs video I/O. On the audio outs, I can quietly hear the video "hum" (vertical sync) and on a spectrum analyser I can see a peak at 15kHz (horizontal sync). There is an audible change in the noise when the main video out changes (e.g. from black to a live picture).

SO.....

Back to my *original* question: Is there any way I can bring in audio from a different sound card and place it on the VT[5] audio mixer?

There is also another good reason I want to do this (besides the noise issue). I have some audio on ADAT optical that I would like to bring in digitally (i.e. no digital-to-analog-to-digital conversion).

[ScorpioProd]

Back to your original question, unfortunately the answer is no.

If you're using the audio for editing in VT-EDIT/SpeedEDIT, any audio files that those programs can read brought in from anywhere could be used. And from SpeedEDIT itself you can feed any audio card for output.

But in terms of on the VT's actual virtual audio mixer, such as for live use, no.

[kevpatt]

Thanks for your answer, disappointing as it is. :cry:

Would be a nice feature request for a future version of VT, though... it would be *great* to be able to use/expand with a professional audio interface. They could use ASIO, for instance.

-Kevin

[Quiet1onTheSet]

Thanks for your answer, disappointing as it is. :cry:

Would be a nice feature request for a future version of VT, though... it would be *great* to be able to use/expand with a professional audio interface. They could use ASIO, for instance.

-Kevin
I trust someone has placed that in the FEATURE REQUESTS Forum many moons ago, if not recently. That's a goodie, for sure!

Hmmmm.

Have any earlier VideoToaster implementations been able to employ external sound cards (or am I just imagining this)?

[ScorpioProd]

It's certainly a good feature request, but I haven't heard it mentioned in years.

As for ASIO, yes, a number of us did request ASIO drivers for the VT card in the past, since I think some Adobe apps totally required them to even run, but there was some reason I can't remember that Newtek didn't feel it was practical to create them for the VT card.

The other thing to remember is that the VT card itself is a VERY old design. So I really wouldn't be surprised if the audio isn't up to the most modern standards and capabilities. I do remember other people finding fault with the audio quality in the past. Myself, it's been so many years since I actually used the analog in/out of the card, having moved fully over to digital, that I only used it for monitoring for the last few years and that was about it. (I only used VT for post, not live.)

Of course, all this should be moot after NAB, since everyone expects Newtek to be introducing a whole new HD based system with all new hardware, at least in TriCaster form, if not VT form.

As for what Peter remembers, yes, he remembers correctly. When the VT card was in its early version, way back around the year 2000 with the VTNT, the audio was not yet implemented in software, though the hardware was already there on the VT card. So, one would add high-end audio cards like the Lynx or some other one in order to do your audio. You would actually connect the Lynx to the VT card in order to keep the audio and video clocks synced up. The NLE software in the VTNT was Speed Razor back then.

[jcupp]

NewTek's SDI option has Digital Audio I/O. It lists at $995 I have a used one for sale if your interested.

If money is no object you could get an SX-SDI and use the AES/EBU I/O. But your looking at three grand.

[Quiet1onTheSet]

As for what Peter remembers, yes, he remembers correctly. When the VT card was in its early version, way back around the year 2000 with the VTNT, the audio was not yet implemented in software, though the hardware was already there on the VT card. So, one would add high-end audio cards like the Lynx or some other one in order to do your audio. You would actually connect the Lynx to the VT card in order to keep the audio and video clocks synced up. The NLE software in the VTNT was Speed Razor back then.

Aahh! Thanks for the memories, Eugene!
:thumbsup:

[kevpatt]

Thanks guys for all the great information.

Myself, it's been so many years since I actually used the analog in/out of the card, having moved fully over to digital, that I only used it for monitoring for the last few years and that was about it. (I only used VT for post, not live.)

When you say "moved fully over to digital", do you mean DV over FireWire? Or SDI? Those are the only ways I can think of to get digital audio into the VT mixer...

As for ASIO, yes, a number of us did request ASIO drivers for the VT card in the past, since I think some Adobe apps totally required them to even run, but there was some reason I can't remember that Newtek didn't feel it was practical to create them for the VT card.

That would be cool too. I was actually thinking of support for ASIO devices within VT, so you could capture from / playback to a ASIO-enabled sound card from VT's internal mixer.

You would actually connect the Lynx to the VT card in order to keep the audio and video clocks synced up.

There's an idea. For professional (external) audio interfaces, NewTek should provide a "Word Clock" output that your audio interfaces would sync to. (feature request) :)

NewTek's SDI option has Digital Audio I/O. It lists at $995 I have a used one for sale if your interested.

Can you use SDI audio in together with S-Video video in, for instance?

[kevpatt]

Actually I have improved the audio situation somewhat. Here's what I did:

I noticed the noise was much worse when connecting long cables to/from the VT. Also, if we connected devices that were on a different electrical circuit there is even more noise. (Don't get me wrong, the VT still has the annoying low-level noise that I mentioned earlier, regardless).

So I found a way to isolate the VT system. I connected a MOTU 896 interface directly to the VT's analog ins and analog outs using short balanced XLR cables. Then I ran a pair of optical ADAT cables to our audio booth where there is a MOTU 828 connected to our mixer. This keeps the whole VT4 system electrically isolated from the rest of our audio setup, PA, etc.

Not a terribly inexpensive solution, but quite effective.

I actually bought these 75 ft. ADAT cables on eBay ($25 each, seller was pro_cable). I had doubts about cables that long actually working, but the seller said they had no complaints and offered a refund if there were any problems. Well they are working perfectly. So I've got 8 channels to and 8 from the VT. :thumbsup:

[ScorpioProd]

Yeah, my move to digital was DV over firewire.

As for the analog audio issues, part of it is the audio connection from the SX-8 to the VT card is unbalanced.

This may be different with the VT Pro card (VT[4] and later) and the SX-84, I don't know about that, but on the older card it's only a 1/8 TRS unbalanced stereo at the card I/O ports.

[Pete Draves]

yes there is computer hash and hum in the VT sound. It has been there since they implemented the on card sound.

I make dozens of DVD masters and tvspots per month and do not want sound like the VT system makes.

I bypass the inboard mixer and take sound out thru the 1/8 th inch jacks to sound ground loop isolator xfmrs from markerteck.

all sound is routed to a behringer ub2222 pro mixer.

this is basically a four bus mixer and can provide sync sound to the "house" and pass through sound to tape output.

the sound is extremely clean.

pd: all sound including the xlrs in toaster are -10 signals and I treat them as such.

I can provide hookup instructions if needed.

I am a professional sound man and have done prosound since the 1960's.

Pete

[Quiet1onTheSet]

Yeah, my move to digital was DV over firewire.

As for the analog audio issues, part of it is the audio connection from the SX-8 to the VT card is unbalanced.

This may be different with the VT Pro card (VT[4] and later) and the SX-84, I don't know about that, but on the older card it's only a 1/8 TRS unbalanced stereo at the card I/O ports.Salient point, there, Eugene; and thankfully, it *is* different (and better) with the VT Pro card -- provided that for audio input/output connectivity, one employs a double-shielded D-sub 15 to D-sub 15 patch cable between SX 8 / SX 84 to said VT PRO card.
:vticon:

[Quiet1onTheSet]

There's an idea. For professional (external) audio interfaces, NewTek should provide a "Word Clock" output that your audio interfaces would sync to. (feature request) :) Aw, May'in. Kevpatt -- you've *got* to place that in the VT Feature Requests Forum, Yo!

(Or was *that* one served up before, already?)

Can you use SDI audio in together with S-Video video in, for instance?Hmmm. I can't help but wonder if you'd then be faced with some sort of latency issue, that would have to force one to consider a "delay" for the S-Video feed.

Can someone afford us some further insight on this (Bob Anderson? Jeff? *Anyone*?)

Another thing I'm curious about, kevpatt is, that we might be able to have further insight about your kuel digitized VT setup with "Mark of the Unicorn" (MOTU) devices. What does each of the two MOTU devices do (how do they differ in functionality)?

I'm guessing that one of them is essentially an analogue-digital/digital-analogue (AD/DA) converter and Firewire Input/output box.

Can you describe how you've got additional gear -- i.e., outboard mixer(s), mics, (and musical instruments perhaps) connected to those two devices in addition to those 2 connections to VT? 'Would really appreciate that!
:beerchug:

[Pete Draves]

The vt pro card audio has no better sound than standard card.
Just as much noise.

Pete

[Quiet1onTheSet]

The vt pro card audio has no better sound than standard card.
Just as much noise.

Pete How unfortunate. Your insights on the audio section over the years, Pete, has been most helpful to many, I suspect. Thanks for chiming in here.

Well, here's looking to the new hardware release that's (hopefully) imminent!
:newtek:

[ScorpioProd]

Opps, nevermind, Pete answered it already.