One Organ, Multiple Computers?

[toomanytoyz]

I am building a VPO using Hauptwerk and Graham Goode's Hollywood Philharmonic Theatre organ sample set. I want as many output channels as possible for maximum realism. I would like to create the following system. All Midi inputs and outputs are via Midi over USB to computer 1. Computer 1 will also handle the audio for the Solo chamber. Computer 2 will handle audio for the Main chamber and will be configured as "Ranks in a box". Computer 1 will route midi info to Computer 2 via midi over ethernet. Both computers would have licensed copies of Hauptwerk Advanced. Am I completely insane? As far as I can tell this should work.

[Larason2]

Yes it should work, but it's not an ideal system. The main problems are latency and lack of synchronization of the clock of your two interfaces. If you use a midi splitter to each system, it will hopefully keep latency down, but you may still find it unacceptable. Also, because of the two different clocks, you may find the longer you play the more the two interfaces get out of synch! This is particularly likely if you hold a long note on one, but not on the other interface, or you have percussive notes on each that have to be timed properly. Some interfaces have a clock out that you can connect to clock in on the other, but this is pretty rare. In my opinion, just use the better of the two interfaces, or get one with more outputs.

[Admin]

Why are multiple computers desirable or necessary for your installation?

[John Kinkennon]

I had inquired about running a pair of HW licensed computers to run two large sample sets on my five manual console with 300 drawknobs. Yes, it is both legal and possible. I would not recommend using a pair of computers with a single sample set and mixed audio as described. It doesn't seem practical or necessary.

[jbird604]

Doesn't Hauptwerk support something like 56 discrete audio channels? A massive VPO in Indiana that was built by Drew Worthen has that many channels, if I'm remembering correctly. But it only has one computer.

You don't need multiple computers. You can connect numerous 8-channel DACs via firewire or other high speed interface, and Hauptwerk should let you arrange your stops or divisions or chambers to use the available channels as you wish.

I would think you need a single computer at the heart of the system, no matter how many outputs or how large the sample set, so the whole thing would respond properly to the capture action, couplers, etc. Spreading it out over multiple computers would surely introduce a bushel basket of problems.

[toomanytoyz]

Due to the way Windows handles audio, the maximum number of channels that you can have is 26, given the audio interfaces that I am aware of. That being said, when I had a smaller instrument 26 channels was more than adequate. The sample set I will be using now has over 30 ranks, plus assorted traps, toys, and tuned percussions. I am transitioning to a 2013 Mac Pro 3.7 Xeon quad core, which theoretically should allow hundreds of channels. Given that I am a cheapskate, I would like to retain use of the existing Windows system, as I have a substantial investment in it. As far as latency, think about how much latency you have on an actual Theatre organ, or on an electro-pneumatic straight instrument with an antiphonal division.

[Vnseppel]

New to the forum but have been in the Hauptwerk VPO world for 13+ years. Version 6 & 7 of Hauptwerk have greatly improved the audio capabilities available. Currently there are 512 stereo channels or 1024 mono channels. Pro-audio interfaces and audio protocols (Dante, as an example) are making leaps too. As an example of a higher end audio interface take a look at the RME UFX interfaces. They are USB 2 (UFX II) and USB 3 (UFX III) and provide an amazing number of channels. They also provide reference quality sound. You will need to add on DAC's (as mentioned by someone else) to convert ADAT channels, for example. But that is easily done providing you have the budget to do it. You can also connect multiple units via your USB ports to multiply your channels. RME has an amazing software mixer (TotalMix FX) that combines the multiple interfaces into a single mixer for further manipulation if you need more capabilities than Hauptwerks itself offers. The interfaces are low-latency, as well and I found them easy to implement into Hauptwerk.

Not sure how many channels you are looking to use so hard to comment specifically, but with the newer computers I would be surprised if you needed to go to multiple computers. Actually, in my experience, the size of the organ plugin is actually what taxes the computer more than the number of audio channels. One of mine is the Billerbeck Fleiter organ. I am running a Dell Precision with dual Xeon 6 core (12 virtual cores each) processors. That provides a lot of computing power. But that organ plugin can work it at times.

Don't know if any of this helps, so --- for what its worth.

[JeremianOrgel]

It's easy to achieve using a midi duplicator. You basically plug the output of one of your midi keyboard to one of this and it will duplicate any midi message coming from your keyboard 6 ways. You can then plug each to a different computer.

Once the sampleset is loaded across all computers and you have detected the midi then what ever you press from your keyboard will play across all instances of your VPO.

The advantage of these asides helping to minimize memory demands on a single computer is also lower CPU demands on each computer. Marshall & Ogletree uses a similar system running Linux clusters

[LTDan]

The number of audio outputs is determined by the hardware and native protocol being implemented. I didn't realize (or care) that the Windows native driver has a limit of 26 channels. The 2 popular protocols for professional multi-channel audio is AVB (Audio Visual Bridge) and Dante. AVB was adopted by MOTU and is available in several of their audio interface units. The limit that "MOTU" has implemented is 72 channels per single chain. You can add more but will require their AVB hub. The massive VPO in Indiana that was built by Drew Worthen which JBird mentions in the above post, uses 2 MOTU 24Ao units plus an 8-channel DAC.

The Dante protocol and its approved licensed equipment like Audinate or Focusrite is used in the professional audio industry, for example a PA system in an airport. I did hear one Hauptwerk setup using just 4 channels via Dante. The sound was fine as Dante is basically just doing the digital/analog conversion then routing. Both AVB and Date incorporate standard Ethernet cabling. Dante can use an off-the-shelf POE network hub where as AVB requires a proprietary hub.

In answer to your desired audio setup, use the Hauptwerk audio and group assignments to route your individual ranks accordingly. You might also consider some more granular routing to keep the 16ft octaves to their own channels/speakers, percussions separate, and celeste its respective unison mate separate from each other. I'm not familiar with Graham Goode's Hollywood set but I'm guessing the Pedal ranks are just offsets like in the Paramount sets or a real theatre organ. So to push those octaves to a more robust speakers, you enlist Hauptwerk's Rank/Split feature.

Regards,

Danny B.
VOCEinstruements.com

[toomanytoyz]

For now I've scrapped the multiple computers idea. I'm having too much trouble with routing, but I'm going to start another topic for that.