Help with Scope as Mixer

pharohoknaughty · Post by **pharohoknaughty** » Sat Mar 18, 2006 11:07 am

I am new to the forum and do not yet have Scope.

Right now I run Sonar in a Athlon 64x2 4800 in a gigabyte 939 nForce 3 MOBO, with Frontier Designs Dakota/Montana.

It is stable as a rock (at least after I put a big fat UPS on the power supply).

I am hesitant to mess around with this machine, since it is the first stable high performance machine I have had.

I was thinking of putting a Creamware Scope card in a second computer, to use as a mixer for monitoring. I already have the second machine, which I use for soft synths, internet, and other chores.

I would run the ADAT out from my A/D converters (Apogee 16 channel) to the Scope card in the second machine.

Then Scope would provide a monitor mix with reverb and eq back to a D/A converter. And Scope would also pass the ADAT unaltered to the ADAT ins on the machine with the Dakota and Sonar. The Sonar machine would have ADAT outs going back into Scope.

Basically, I would like to replace my Roland VM-7200 digital mixing board with the Apogee converters and Scope, all external to the Sonar machine.

I think this would work OK but I am concerned that the Scope will have too much latency in passing the ADAT signal to the Sonar machine.

Many people advise putting the Scope card in my Dual Core Sonar machine, and not using the second machine as a bridge. But I have heard of instability problems with Scope in Dual machines. And the Sonar machine I have setup is so blissfully stable.

Any thoughts?

astroman · Post by **astroman** » Sat Mar 18, 2006 11:48 am

welcome first of all - and congrats for your perfect reasoning about your 2 systems

you've hit the nail on the head and may invest what you can spare on the Scope machine (it really doeasn't need much without a sequencer) in a sync plate (a studio clock might be present already) for improved digital connections.

At 44.1 khz the Adat latency for a full round-trip is probably in the 20 sample range, or close to 0.5ms, at least those were my figures with a Korg digital mixer once.

the most important point for that 2nd system's mobo is the PCI performance, as Scope accesses main memory via this path.
Anything else is more or less arbitrary.

A good choice for the P4 is the Intel 865 chipset, for the P3 it's the Intel 815, the favourite is the ASUS TUSL-2c.
The latter is still fairly widespread here, it's of course a 2nd hand only option.
It may have it's advantages tho in a rack unit under Win98 - I run it from a 2GB flash disk.
regarding the CPU: as a mixer/synth/fx box any Celeron does the job

cheers, Tom

[ This Message was edited by: astroman on 2006-03-18 11:58 ]

Post by **irrelevance** » Sat Mar 18, 2006 11:49 am

I don't think you would have a problem with latency there.
I'm only using one computer but basically my scope synths output via asio to my sequencer which passes the signal out via asio to scope for fx either as insert or send.
I don't notice much latency at all and don't usually have to bother with latency compensation either.

Post by **irrelevance** » Sat Mar 18, 2006 11:52 am

I was wondering how long exactly it would take to the signal to travel. In my experience and for my purposes (unmeasured) It's instantaneous. nice one astro.

astroman · Post by **astroman** » Sat Mar 18, 2006 12:00 pm

you can measure the time with the sample delay of the 2448 mixer if one channel is fed directly and the other after the journey, but you can also test any device for internal latency...

pharohoknaughty · Post by **pharohoknaughty** » Sat Mar 18, 2006 3:19 pm

On 2006-03-18 11:52, irrelevance wrote:
I was wondering how long exactly it would take to the signal to travel. In my experience and for my purposes (unmeasured) It's instantaneous. nice one astro.

Is there anyone who has tested this?

I guess I could get a Frontier Apache, which can split one ADAT input into two outputs, and run the split signals to both computers at once. The Apache has zero latency, but adds another $600 and complexity to the project.

astroman · Post by **astroman** » Sat Mar 18, 2006 5:18 pm

yes, me - as written above

the following way:
a signal is send to a sample delay and out of that into a mixer channel
the same signal - yes, SFP can do the same trick as the Apache as a bonus

is sent to Scope Adat Out, connected to the external Mixer's Adat In.
The Mixer sends it back via another Adat channel, which is connected to Scope's Adat In and routet to another channel of the afforementioned Scope mixer

Now both the original and the 'trip' signal play - phasing of course

invert one of the channels and increase the sample delay until the sound extinguishes
read the value from the delay

in my case it was 20, and since the signal made 4 Adat In/Out transitions that would give about 0.15 ms per adat connector

cheers, tom

[ This Message was edited by: astroman on 2006-03-18 17:21 ]

pharohoknaughty · Post by **pharohoknaughty** » Sat Mar 18, 2006 6:21 pm

Thank you

Very encouraging

dawman · Post by **dawman** » Sun Mar 19, 2006 9:19 am

Brotherman Astro,
It is good to see that you still help people on the forum who are new. Pharoh, welcome. I have 2 boxes, 1 is overkill w/P4SCT+II, 2nd is 4 live performance w/ 865P/3.0GHz, they both are stable w/GS3 Orchestra, and the synths will be encouraging also. As you could tell, Astros word is good round here, a year ago I toured w/ a stage full of hardware, now I only use a few pieces thanks to guys on the forum.

Strtength Through Superior DSPs,

_________________
Jimmy V.

[ This Message was edited by: scope4live on 2006-03-19 09:20 ]

astroman · Post by **astroman** » Sun Mar 19, 2006 9:45 am

hi Jimmy,

tnx for the compliments
and while you're here - yesterday I remembered your 'remove the vocals from a mix' problem on some old records when I read a review of <a href=http://www.algorithmix.com/en/renovator ... Novator</a> - they are the dudes who wrote Osiris and Restore - it's probably the most advanced 'affordable' in this domain

cheers, Tom