MOTU MTP-AV (parallel) on SX3 PC kills CPU load?

narly · Post by **narly** » Wed Jan 19, 2005 10:14 pm

Does anyone have experience using a MOTU MTP-AV Parallel interface with Cubase? I'm using with SX3 and midi controller traffic (i.e. CC1 modwheel) can easily push the CPU load high enough to break up my audio. If I disconnect the MTP and use a Pulsar Midi in instead, no problems...so I guess the MTP is the issue(?) I'm wondering if the parallel is just a bad choice and if the USB model is any better - I'm not real confident using MOTU stuff on PC anymore.

Some details of my setup include SX3.01 on P4 2.4GHz / 512Mb SDRAM / WinXP Pro with most of the simple recommended performance tweaks (disabling unnecessary features, etc.). System uses Pulsar 2 x2 in XTC mode, 32 ASIO channels in, 34 out - using ASIO1 16 driver. Plus a TC PowerCore in the box. Test conditions are with about 80% load on the Pulsars with synths, approx 16 channels monitor enabled in SX3, and 7ms input latency on the pulsars. Output is to 5.1 bus. VST Performance shows approx 20% CPU utilization prior to initiating midi traffic. Rolling modwheel can redline CPU when using the MTP but not always; about 5-10% fluctuation in CPU with same traffic in through the Pulsar input.

Any similar experience or recommendations are appreciated. Maybe I've set up something wrong? But this is a clean install of everything and it did similarly on Win2k Pro.

Assuming the MTP-AV Parallel is a problem, what's a good multi-channel interface to use? I like the simultaneous interface/patchbay/merge function capability of the MTP-AV and would rather not lose that feature... TIA -

[ This Message was edited by: narly on 2005-01-19 22:21 ]

CarlosRanoya · Post by **CarlosRanoya** » Thu Jan 20, 2005 9:15 am

Perhaps the issue is the last MTP-AV drivers (I think version 2.5, not shure).

I´m using MTP whith Logic Audio 5.5.1 for a long time. Whith this driver, strange things happen. Some kinds of MIDI messages are recorded in my MIDI tracks, like SysEx and CCs. When I turn on MIDI Clock Out from Logic and play the music, Logic becomes a big and slow turtle. Sometimes the MIDI in from MTP stops and I need to execute the the MTP Console. Then it works.

I lost the older driver I used, but it was very better. This was not the first version of WindowsXP drivers, this one was bad, too.

Is other one having this problems?

narly · Post by **narly** » Thu Jan 20, 2005 7:26 pm

I found a backdoor address to get older drivers from the MOTU site:

http://downloads.motu.com/MTPWin/

I'm going to give some of these a try.

Current driver 2.51 is crap AFAIC... Makes no sense why so much CPU fluctuation for the amount of MIDI traffic coming in. The Creamware MIDI In port seems to handle this easily!

I've also noticed that the symptom is MUCH less exaggerated (almost non-existent?) when I don't load the Powercore01 synth for the TC Powercore card - go figure! Maybe time to do some research on the TC Electronic site as well - will post any positive findings here, of course. Thanks for your corroboration.

[ This Message was edited by: narly on 2005-01-20 19:27 ]

narly · Post by **narly** » Fri Jan 21, 2005 5:12 pm

I'm using what I'll call the 2.00 drivers, although MOTU seems to not have given it that designation. It's the first install set with "Clockworks" and the last before the set they call 2.10. On the download site it's "SETUPM~1.ZIP" and is dated 15-Aug-2002.

This install only creates two devices under "Sound, Video and Game Controllers" whereas the later versions create 2 devices in the "System Devices" plus one in "Sound, Video and Game Controllers." The performance seems better, but there is still a big jump in CPU utilization for what should be moderate streams of incoming CC data.

I'm still not entirely satisfied with the performance hit and would be interested in hearing whether anyone has this type of issue with a MTP-AV USB or not. Of course, recommendations for other similarly featured interfaces are also of interest.

A CPU (and mobo/RAM) upgrade may be desirable to overcome some of this, but $ are tight right now. I guess I could find some gear to sell

narly · Post by **narly** » Sun Jan 23, 2005 12:57 pm

Given some input from a response on Cubase.net ( http://forum.cubase.net/phpbb2/viewtopi ... 1162#21162 ), I removed and re-installed the Syncrosoft component for Cubase protection making sure to not install "Parallel Device Support." Things are better, but only with the older MOTU drivers. There's no longer an apparent impact on audio, but it's possible to kill incoming note timing with CC traffic... Updating to Windows XP SP2 also seems to have lessened the symptoms.

Is anyone successfully using something like a MidiSport 8x8 and just doing the in/out patching to external HW synths internally in Cubase SX or other DAW soft? I'd rather move on to another interface if there's something out there that doesn't burn up so much CPU bandwidth and can handle the routing aspect...

Thanks!

[ This Message was edited by: narly on 2005-01-23 12:58 ]

[ This Message was edited by: narly on 2005-01-23 12:59 ]

narly · Post by **narly** » Thu Jan 27, 2005 9:22 pm

I've given up on the MTP-AV parallel. More problems abound. I have hobbled my setup to using 1 input on the MTP for about 6 midi channels and have setup in SFP mode to limit Cubase MIDI handling. Seems reliable for my purposes for the moment.

I'm getting a MidiSport 4x4 USB and expecting great things from it! Mac users who want a MTP-AV Serial (w/ GeeThree serial port) - mail me!

Long and short is that MTP-AV may work well via serial to a Mac - but I would never recommend one to a PC user!!!

Thanks for input provided...