# How to reduce latency on a scarlett 2i4 and reaper?



## 888 (Aug 12, 2015)

I'm currently running my guitar through the instrument input on my focusrite scarlett 2i4 into Bias through reaper, with a few pedal and gate vsts. Right now my latency is extremely high, and very noticeable (32ms). I have the buffer in the focusrite driver set to 1ms and 5x600 in reaper preferences. Any lower than that and the playback quality would go to ****, even though cpu usage was never above 23% on a single core and 7% overall. Does anyone know how I could reduce my latency to the point it's not noticable?


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## Drezik27 (Aug 12, 2015)

888 said:


> I'm currently running my guitar through the instrument input on my focusrite scarlett 2i4 into Bias through reaper, with a few pedal and gate vsts. Right now my latency is extremely high, and very noticeable (32ms). I have the buffer in the focusrite driver set to 1ms and 5x600 in reaper preferences. Any lower than that and the playback quality would go to ****, even though cpu usage was never above 23% on a single core and 7% overall. Does anyone know how I could reduce my latency to the point it's not noticable?



I had a small latency problem using Reaper and Revalver. The link below solved it for me:

How to deal with interface latency (delay/lag) - Cockos Confederated Forums

Another thing you could try is get the ASIO4All driver. I've read that has helped folks as well.


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## Dusty Chalk (Aug 13, 2015)

Yeah, that's true of almost all softwares -- it's not in the software, it's in the output driver. Find the preferences, then look for something like "audio buffer" and set it as low as you can.


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## cwhitey2 (Aug 13, 2015)

Drezik27 said:


> I had a small latency problem using Reaper and Revalver. The link below solved it for me:
> 
> How to deal with interface latency (delay/lag) - Cockos Confederated Forums
> 
> Another thing you could try is get the ASIO4All driver. I've read that has helped folks as well.




This.


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## tedtan (Aug 14, 2015)

Or, if you can spend the money, you can all but eliminate latency entirely by getting a thunderbolt or PCIe based interface instead of firewire or USB.


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## Rev2010 (Aug 14, 2015)

tedtan said:


> Or, if you can spend the money, you can all but eliminate latency entirely by getting a thunderbolt or PCIe based interface instead of firewire or USB.



That's not entirely accurate. There are plenty of firewire interfaces that have latency exactly comparable to many PCI/PCIe devices. For USB3, RME has the best drivers with the lowest latency that is only a hair behind their PCIe interfaces.

It's really not as cut and dry as the port or slot it goes into. The DAW latency database shows excellent firewire performance for the Mackie Onyx Blackbird with their newest redesigned drivers (TC Applied). Reposted image from Gearslutz:


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## 888 (Aug 17, 2015)

cwhitey2 said:


> This.



I can't seem to get the asio4all drivers working. Everything installs fine and it recognises my interface but I can't choose it as a playback or input device in reaper.


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## 888 (Aug 17, 2015)

Ok so I've gotten reaper to recognise the asio4all driver, but It's not detecting any input from my guitar. How do I fix this?


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## tedtan (Aug 17, 2015)

888 said:


> Ok so I've gotten reaper to recognise the asio4all driver, but It's not detecting any input from my guitar. How do I fix this?



Does it recognize your interface? Can you play back audio through your interface? If so, you probably need to select the correct input and arm your track for recording.


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## tedtan (Aug 17, 2015)

Rev2010 said:


> That's not entirely accurate. There are plenty of firewire interfaces that have latency exactly comparable to many PCI/PCIe devices. For USB3, RME has the best drivers with the lowest latency that is only a hair behind their PCIe interfaces.
> 
> It's really not as cut and dry as the port or slot it goes into. The DAW latency database shows excellent firewire performance for the Mackie Onyx Blackbird with their newest redesigned drivers (TC Applied). Reposted image from Gearslutz:



I'm not sure how they measured latency in that chart, but if I'm interpreting it correctly, we're looking at 3+ milliseconds of round trip latency across the board, even with very low buffer settings. Some of the thunderbolt interfaces (and old Pro Tools HD setups) are in the 1 millisecond or less round trip latency range with higher (e.g., more stable) buffer settings.

I'm sure there are poor driver implementations with both thunderbolt and PCIe based interfaces, but the better implementations seem to be the lowest latency options available from what I'm seeing.


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## Rev2010 (Aug 17, 2015)

tedtan said:


> Some of the thunderbolt interfaces (and old Pro Tools HD setups) are in the 1 millisecond or less round trip latency range with higher (e.g., more stable) buffer settings.



That sounds exaggerated. If Thunderbolt interfaces were achieving such low latencies, and at higher buffer settings, I think Gearslutz.com would be awash with everyone talking about it and switching over and I haven't heard anything like this. Care to link to where you're seeing this information? As for the chart I posted, it was the result of tests done by DAWBench. Look them up if you're curious.

*EDIT - just did some reading up. I think you're referring to running the interface at 96khz, which is what you would need to run it at to achieve that low latency. I am referring to using it at the standard 44.1khz.


Rev.


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## manana (Aug 18, 2015)

I have never been able to get reaper latency low enough to live monitor my guitars or drums if I am monitoring through the DAW. I love reaper but that is the only thing they really suck at. You are going to have to monitor through your interface.


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## tedtan (Aug 18, 2015)

Rev2010 said:


> That sounds exaggerated. If Thunderbolt interfaces were achieving such low latencies, and at higher buffer settings, I think Gearslutz.com would be awash with everyone talking about it and switching over and I haven't heard anything like this. Care to link to where you're seeing this information? As for the chart I posted, it was the result of tests done by DAWBench. Look them up if you're curious.
> 
> *EDIT - just did some reading up. I think you're referring to running the interface at 96khz, which is what you would need to run it at to achieve that low latency. I am referring to using it at the standard 44.1khz.
> 
> ...



Yeah, you're right - 96K or 192K are needed to achieve the lower latencies, and the specs I've seen have utilized one of those sample rates in order to achieve them.

From what I've seen, Pro Tools HDX using the Pro Tools HD I/O interface (PCIe version) is capable of achieving 0.7 milliseconds round trip latency at 96k without processing (e.g., no plugins; adding plugins increases the latency - see chart in post #2 here) and Focusrite is advertising their new Clarett line of thunderbolt interfaces as sub one millisecond, though I haven't seen independent third party confirmation of either of those numbers yet.


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## Rev2010 (Aug 18, 2015)

tedtan said:


> Yeah, you're right - 96K or 192K are needed to achieve the lower latencies, and the specs I've seen have utilized one of those sample rates in order to achieve them.



That's the problem. Recording at those high sample rates entails a huge overhead - cpu and disk space, so it kind of defeats the lower latency benefit. I've seen 1.5ms latencies on current firewire and pcie devices at 96khz. At 1.5ms you're pretty much set as it's really not noticeable. Heck, I run my older Mackie Onyx 1220 at 64 buffers and the latency is so low I can play my softsynths and even record my guitar monitoring from the DAW using amp sim software without even feeling the latency. But, since I have a POD HD I'm usually recording that and monitoring through my mixer which is basically zero latency. Of course there's latency with everything, even the POD HD has it's own processing latency no matter how imperceptibly small it's still a certain amount. 


Rev.


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## 888 (Aug 23, 2015)

tedtan said:


> Does it recognize your interface? Can you play back audio through your interface? If so, you probably need to select the correct input and arm your track for recording.



Everything works fine when using the focusrite drivers.


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## Dana (Aug 23, 2015)

Just mute the channel you're recording to. Then adjust your direct signal mix with your reaper tracks on the 2i4.
Done. 
Unless I'm missing something here


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## Dana (Aug 23, 2015)

Of course this means you'll only have a clean signal to listen to -/


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## thevisi0nary (Aug 23, 2015)

Buy a very fast computer and you should never have to worry


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## thevisi0nary (Aug 23, 2015)

Then also you can have a dedicated recording computer and not have any other installs that interupt performance, which has been a problem for me.


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## kkuehl (Aug 28, 2015)

I have reaper (5.01)and the scarlet 2i4 myself.
Today I installed the beta drivers from here: Focusrite / Novation Beta Testing :: Releases
and also did the following adjustments: Optimising your PC for audio on Windows 10 | Focusrite
and went from the same 32ms down to 16ms. Looking to drop this further obviously.
I'll be watching this thread. If I solve it first, I'll post here.


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## kkuehl (Aug 28, 2015)

888 said:


> I can't seem to get the asio4all drivers working. Everything installs fine and it recognises my interface but I can't choose it as a playback or input device in reaper.



I just use the scarlett drivers themselves. This shows up as ASIO in Reaper, not ASIO4ALL.


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## Lokasenna (Aug 28, 2015)

manana said:


> I have never been able to get reaper latency low enough to live monitor my guitars or drums if I am monitoring through the DAW. I love reaper but that is the only thing they really suck at. You are going to have to monitor through your interface.



Reaper is almost definitely not the culprit - it's usually one of the faster DAWs out there, if anything, since it has so much less overhead than the big boys.


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