Topic: HDSPe MADI - Mainstage latency problem

We have just installed an HDSPe MADI into our Mac Pro.

We are running Mainstage with plenty of RAM, through the HDSPe, into an A&H iLive iDR32, but the latency is TERRIBLE.  The system has run through a MOTU 896 for 3 years, with no latency problems.  The samples stream off an SSD, and it has been running extremely quickly.

Does anyone have experience of reducing latency in this situation?

Many thanks in advance

Guy Harris
PianoJam BV

Re: HDSPe MADI - Mainstage latency problem

Please provide a more detailed description of the "latency" phenomenon you are referring to.

Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

Re: HDSPe MADI - Mainstage latency problem

Hello Daniel,

Thanks for your reply.

The system is as follows:

Computer
Mac Pro Quad Core
12GB RAM
System drive:  15000rpm SAS
Sample drive:  SSD
HDSPe MADI (Software Version 2.76)
OSX 10.6.6
Logic 9
Mainstage 32-bit Version 2.1.2

Mixer
A&H iLive iDR32 (Firmware 1.71)
M-MADI-A

Mainstage is running samples triggered by MIDI from external keyboards.  There is no difference between the response of the system to the Logic-based samples or the 3rd party samples, such as Synthogy Ivory 1.72.

When the keyboards are played, the resulting sound from the outputs from the mixer are +/- 50ms delayed, which makes them unplayable.  I haven't yet had time to measure the latency accurately, but I know from (bitter) experience approximately how much latency is occurring. 

The RME HDSPe settings 'app' tells me that both Word Clock and MADI sync are available.  Switching from one to the other has no effect; neither does making any given unit master or slave.  Just to experiment, we even used various co-axial cables with different resistance.  The Mainstage IO buffer was set to 32 samples (the lowest setting possible) with no IO safety buffer.  All units / systems are set to 48000Hz.  There appears to be no way to set the latency of the HDSPe, although the manual says that there are:

[q]"8 available buffer sizes/latencies:0.7/1.5/3/6/12/23/46/93ms"[/q]

I have contacted the supplier here in Holland, TM Audio, and he has tried to help me over the phone, without success, but will make inquiries.

I hope I've given you all the information you need! :-)  If not, please let me know what more I can provide!  I will measure the latency accurately on Monday, in the workshop.

Thanks ...

Guy Harris
PianoJam BV

Re: HDSPe MADI - Mainstage latency problem

The buffer is selected inside the app preferences on Mac OS. Do you notice any difference on the Phones out of the MADI card?

Regards,
Jeff Petersen
Synthax Inc.

Re: HDSPe MADI - Mainstage latency problem

Hi Jeff,

Thanks for that: I thought it would be in the main panel in the 'app' itself.  I will check tomorrow, and thanks for the heads up!  I will also check the analogue out on the card itself.

Guy

Re: HDSPe MADI - Mainstage latency problem

The buffer set in Main Stage, or Logic, or any Mac app prefs is your audio card buffer. In my experience a 32 or even 64 sample buffer results in no discernable latency for virtual instruments, so I expect you will find the problem is outside the RME card. Make sure you have disabled any software effects for your test. The phones out will tell you for sure.

Regards,
Jeff Petersen
Synthax Inc.

Re: HDSPe MADI - Mainstage latency problem

Hi Jeff,

Yes:  I ran the instruments 'pure'.  I would be surprised if the problem is anywhere else except with the card, or the settings thereof, because we've run the same system using both old and new MOTU896s for 3 years, without any problems whatsoever! :-)  I will try using a different host on Monday; just running samples from Audacity or something similar.  The buffer setting is one thing; but my limited understanding is that the latency can be set from within the 'preferences' in the app?  Looking through the manual, I see screenshots for this under the PC installation, but not the OSX version.  The system seems very stable and 'clean', as one would expect, so I'm hopeful that maybe being able to access the latency / buffer size from within the RME software, as opposed to Logic / Mainstage, will fix the problem ... :-)

Guy

Re: HDSPe MADI - Mainstage latency problem

Exactly as I said above. On PC buffer is set in the HDSP settings, on Mac buffer is set in the application preferences (Main Stage, etc.)

Regards,
Jeff Petersen
Synthax Inc.

Re: HDSPe MADI - Mainstage latency problem

In which case, it's nothing to do with Mainstage, as that is set to 32, the lowest setting ...

G

Re: HDSPe MADI - Mainstage latency problem

I couldn't stay away ... even on a Sunday! :-)

The latency problem is fixed:  I tried a fresh Mainstage scene, from scratch, as opposed to the saved scenes we had from the shows, and the latency disappeared, at least on the analogue output from the HDSPe card, so I presume it'll be OK once connected to the iLive.

Thanks for the help, Jeff!

Guy