Latency of USB-Interface of SQ?

Forums Forums SQ Forums SQ general discussions Latency of USB-Interface of SQ?

This topic contains 23 replies, has 10 voices, and was last updated by Profile photo of Keyguy Keyguy 1 year, 10 months ago.

Viewing 9 posts - 16 through 24 (of 24 total)
  • Author
  • #82170
    Profile photo of KeithJ A&H
    KeithJ A&H

    Hi All,

    The SQ’s USB interface offers 32×32 channels at 96kHz, this is no small feat, especially when it is only one part of the system as a whole. I would therefore suggest it is an unfair comparison to put the SQ next to a dedicated interface when comparing latency (especially as some models from the manufacturers mentioned here which have the same channel count are around 50% of the cost of the whole SQ!).

    Saying that, the latency does not make the USB port unusable, and we even have people using it for inserting time critical channel processing in a live environment, which is something that we would not generally recommend… but as has already been pointed out, the computer is by far the biggest variable in a system utilising the USB connection.

    It is well known that the latency of the SQ itself is extremely low – less than 0.7ms from analogue input to analogue output. One of the reasons this is so desirable by engineers is because the SQ may only be part of a whole system of devices that all add their own latency (radio microphones, IEM packs, system processors etc…). So we definitely understand the need for low latency, and have provided multiple options for internal and external processing so you can get exactly what you need. Here’s a quick overview:

    USB-B: 32×32 channel, 96kHz, great for use with a DAW for recording or playback, also useful for non-time-critical processing such as reverbs and delays, carries MIDI, class compliant on Mac, requires nothing more than a USB cable to connect to a computer.

    DEEP plugins: High end modelling of classic processors from our flagship range, insertable directly in the channel, zero added latency (so still less than 0.7ms input to output, and phase coherent), no extra cables or equipment, compressors can be used in place of any stock compressor, GEQ’s used in place of any stock GEQ, Preamp can be used on every input channel.

    Waves option card: 64×64 channel 96/48kHz, provides connection to other Waves SoundGrid equipment, can be connected to a computer running the virtual sound card with latency dependant on system (but generally lower than USB), connect to Waves servers (these are heavily customised PC’s with Waves drivers that offer much lower latency than a standard computer).

    Dante option card: 64×64 channel 96/48kHz, connect to any Dante network, can be connected to Dante Virtual Soundcard on a computer (adds latency, 64×64@48kHz, 32×32@96kHz), low latency options via PCIe cards, great for recording at higher channel count and interoperability between thousands of different pieces of equipment.

    So it just depends on your requirements.


    Profile photo of SteffenR

    the SQ is not a dedicated audio interface, it is a live sound mixer in the first place, but it’s usable as a project studio interface

    10ms with a mixer with an inbuild USB audio interface is not that bad…
    connect your MOTU to USB and measure it again,
    this will have more than 5ms or mmaybe it doesn’t work?

    It seems that when playback commences, the driver tries to establish sync with the SQ. This “point of sync” varies from recording to recording. That means, even with delay compensation enabled in Live, you will never be able to get phase coherent recording and playback, because the round-trip latency is non-deterministic from session to session.

    this is simply not true,
    since the audio software is responsible to make shure the playback and recording is in sync and phase coherent…
    the settings in the session will remain coherent, that’s all what matters

    Both these solutions seem like a huge hack considering the mixer has a USB port and should be more than capable of ~3ms RTL @ a 64 sample buffer with 96kHz sampling. A&H, please get your act together and fix this problem.

    the problem is the USB interface in general, this will not work with a latency around 2ms
    Thunderbolt was introduced to allow lower latency as possible with USB

    Profile photo of jmole


    The ASIO driver is supposed to report the latency to the DAW, which then uses this number for delay compensation between I/O tracks. Not only is the number reported *wrong*, but the measured round-trip latency *changes* each time you hit stop and play again.

    It’s a broken ASIO driver, and a bug that needs to be fixed. This does not happen on mac, thankfully.


    I have a Dante interface on the way, and will do some latency measurements of the system using Dante with VCS and also a thunderbolt connected Focusrite 4Pre /w Dante to see how it all shakes out.

    The annoying thing about this is that with the extra cost of the SQ Dante card and the {Rednet PCIeR, RME Digiface Dante, or Focusrite Red 4Pre/8Pre/16Line interfaces} for the PC/Dante connection, I’m pretty much up to the cost of Waves’ new eMotion LV1 live mixer bundle, which will do most of the real-time processing I’m looking to do natively through my DAW.

    Profile photo of SteffenR

    the Dante interface with DVS will not solve your problem, since there is no very low latency connection to the computer is possible without the PCIe cards…

    So, why you need that low latency?

    Profile photo of jmole

    My plan is to use the focusrite as a low latency thunderbolt to Dante converter. Apparently the rednet PCIe cards only get you <3ms RTL, the thunderbolt interface will do 1.6ms @ 32 samples 96kHz.

    The reason thunderbolt is faster is because it’s a different driver developed by focusrite, vs the PCIe card which is just a rebranded Audinate product.

    The main use is for vocal effects like vocoding, hardtune etc, which need to be as close to real-time as possible.

    Profile photo of Troubleshooter

    Running WIN10 and Cubase 10 with 256 buffer on an SQ6, though never record more then 4-8 channel at same time, mixing around 16-24 channel.
    I have not checked what delay I actually have, but no problem with delay when I run UAD guitar amp simulations like Diezel Herbert of Savage
    120 in realtime, I’m happy with the by of SQ6 as centerpeace in my home/project studio. Is this maybe an dedicated issue with USB drivers for
    Mac that creates this?

    Profile photo of SteffenR

    no it has nothing to do with the Mac, the problem is just in his mind

    Avid Venue SC48 has more than 10ms latency and you can add plugins (including Waves) that lead to over 20ms, nobody is complaining…
    if the latency is a problem we do not process the signals with additional plugins,
    so in monitor world be economical with plugins

    the SQ was designed to work as a mixer with additional ability to record live performances with computers and as recording frontend within project studios
    in both situations it is not an issue that the USB interface has a latency higher than 5ms


    My plan is to use the focusrite as a low latency thunderbolt to Dante converter. Apparently the rednet PCIe cards only get you <3ms RTL, the thunderbolt interface will do 1.6ms @ 32 samples 96kHz.

    the Thunderbolt interface will add one more Dante hop that adds latency as well

    The reason thunderbolt is faster is because it’s a different driver developed by focusrite, vs the PCIe card which is just a rebranded Audinate product.

    no it’s not significant faster, since it is a PCIe bus packed on a cable that needs to be converted too

    we talk about latency of around 3ms
    that is very low already
    and use of a digital pitch shifter as a device will add more latency since pitch shifting is a delay based FX

    Profile photo of jmole

    The latency on Windows is indeed lower than it is on Mac. I think the minimum RTL I saw on Windows was around 5ms, vs the 10ms for Mac.

    Profile photo of Keyguy

    Thinking about getting a SQ6 but have a connection question.
    I run my Keyboard setup using virtual instruments under Reaper. I use an RME MADI card that goes out to the MADI card on my Midas M32.
    This works great as I don’t have to go thru any converters till the mains out.
    Since there is no MADI interface for the SQ series I’m trying to figure out how to get my MADI output into the SQ mixer.
    One idea I have come up with if it’s doable is use a Motu M64USB/AVB with MADI to convert the MADI output to USB.
    Are the USB drivers on the SQ6 class compliant?
    Has anyone tried this to see if it works?


Viewing 9 posts - 16 through 24 (of 24 total)

You must be logged in to reply to this topic.