How to record guitar, Focusrite, ART DPS II

R

RSullivan

New member
This is a real newbie question!

I have:
1.) Dell 8900. I believe that the sound card is a Realtek ALC3861 7.1 integrated audio (No digital inputs!)
2.) Reaper.
3.) ART DPS II Pro.

I am re-starting my home recording studio (getting rid of old equipment, moving to DAW).
I want to record my guitar via mike'ing the cabinet (I do not like DI / Emulators).

It seems I have two options:
1.) ART DPS II Pro.
But my Dell 8900 does not have a digital input on it (Digital outputs on the ART are S/PDIF & ADAT).
So it seems to me I would need to purchase a 'better' sound card with digital inputs. Am I correct?
If so any suggestions for the sound card?
2.) Focusrite 2i4.
Maybe I should just purchase one of these?
It seems that the sound card would be irrelevant then?
About USB:
I am a programmer and the usage of USB in this device makes me somewhat Leary.
It seems to me that USB (the 'S' is for serial) would cause additional latency? Am I correct?

Thanks for any input.
 
Pretty much all USB recording interfaces have a low latency input monitoring feature. This bypasses the trip to the computer entirely and routes the signal to the line and headphone outputs more directly. One common way to do it is with a simple analog mixer circuit inside the interface, usually with a knob to control input/playback balance. That gives you true zero latency monitoring. Many interfaces use onboard DSP controlled by an app on the computer. This has very little latency if set up correctly.
 
Thanks for the help (and patience).

So, I will run out tomorrow and get a Focusrite 2i2.
I will use the ART as a Preamp if I think it sounds good.

I believe everything you are saying and am sure that an 2i2 will work for me but I still have
A curiosity / question about 'monitoring'.

I have read the Focusrite 2i2 manual.
It says I will set the default input and output in my DAW (Reaper) to the 2i2.

Ok, I get that.

There is a single connection from the 2i2 to the PC. It is USB 2.0.

So to monitor while recording (Guitar):
'
You will frequently hear the term “latency” used in connection with digital audio systems.
In the case of the simple DAW recording application described above, latency will be the time it takes for your input signals
to pass through your computer and audio software. Latency can be a problem for a performer who wishes to record while
monitoring their input signals.

The Scarlett 2i2 is fitted with a “Direct Monitoring” option, which overcomes this problem.
Setting the front panel “Direct Monitor” switch to ON will route your input signals directly to the Scarlett 2i2’s headphone and
main monitor outputs. This enables you to hear yourself with zero latency – i.e., in “real time” – along with the computer playback.

The input signals to your computer are not affected in any way by this setting.
'

So I can (with Direct Monitoring):
1.) Have my Reaper output set to the 2i2. So when recording my Guitar all other tracks can be heard via headphones attached to the 2i2.
2.) My live guitar input signal on the 2i2 is mixed into Direct Monitoring function so I am hearing it along with the output of
the other tracks in Reaper on the headphones.
3.) I understand that my armed recording track should NOT output to the 2i2 when recording.

My question:
Since the only connection from the PC to the 2i2 is USB 2.0 this can only mean that the 'output' signal is being transmitted from
the PC to the 2i2 over USB? This seems unnatural to me and would inject latency between the guitars input signal and the Reaper's output signal.
How much latency I have no idea. Perhaps it is so low it is unnoticeable to the human ear?.

Again, this is just a question. I am sure it all works as long as there are plenty of CPU and BUS cycles available (i.e. no background tasks
running on the machine soaking up CPU cycles).

I am asking this question due to my background with USB.
I am a programmer. I Primarily write software that runs industrial automation within assembly factories (mainly automotive).
I am very well aware of the fact that USB is serial, and by definition will produce 'Latency' (the sound recording term for the
effect of a non-synchronous protocol, i.e. it is asynchronous). I have written many USB drivers.

Thanks again.
 
RSullivan said:
My question:
Since the only connection from the PC to the 2i2 is USB 2.0 this can only mean that the 'output' signal is being transmitted from
the PC to the 2i2 over USB? This seems unnatural to me and would inject latency between the guitars input signal and the Reaper's output signal.
How much latency I have no idea. Perhaps it is so low it is unnoticeable to the human ear?.

Again, this is just a question. I am sure it all works as long as there are plenty of CPU and BUS cycles available (i.e. no background tasks
running on the machine soaking up CPU cycles).

I am asking this question due to my background with USB.
I am a programmer. I Primarily write software that runs industrial automation within assembly factories (mainly automotive).
I am very well aware of the fact that USB is serial, and by definition will produce 'Latency' (the sound recording term for the
effect of a non-synchronous protocol, i.e. it is asynchronous). I have written many USB drivers.

Thanks again.
Click to expand...

The direct monitoring function bypasses the round trip to the computer. It's entirely inside the interface.
 
Thanks Boulder.
I am sure I am not wording my question correctly.

I understand that the input Guitar-Amp->Cabinet->SM57->2i2 during recording is not round tripped.
I am asking about the 'monitoring' of the other tracks via the headphones attached to the 2i2.
For instance when I record a Guitar track I need to hear the Drums and Bass which is coming out of Reaper during recording.
It seems that the Reaper output (Drums, Bass) would appear within the headphones (Am I Correct with this assumption?), but again, it seems that the
Reaper output is going to the 2i2 drivers (as an output device), from the drivers over USB, and finally ending up within the 2i2 where I will hear it?

Am I correct about this?
If I am I do not understand how signal (the output from Reaper) going over USB does not have a latency issue.

Thanks again.
 
Whatever delay there is on the playback side doesn't matter for monitoring because you don't have anything to compare it to.

As long as the interface accurately reports its output and input delays they can be accounted for in the DAW so new tracks line up with earlier tracks on the timeline. The system knows how long it takes the playback to get to the interface and for inputs to get back to the DAW so it simply adjusts the position of new tracks on the timeline by the total of those two values.

If it were a problem there wouldn't be thousands of people buying and using USB audio interfaces. This is well developed technology and it works just fine the majority of the time.
 
The Latest generation of Focusrite interfaces are said to have very low latency.
You are somewhat correct in saying that the PC needs to be fast and optimized for audio (disable that OB soundcard!) but the vast majority of latency problems are caused by interface issues and poorly written drivers.

I can understand why you want to include the Art pre in the chain but I am confused by its ADAT function? It seems to be resolutely a 2 in 2 out pre amp and thus why would you need 8 track ADAT? Howseedoosies, IF you know why and you want to use the ADAT function you will have to go up a few $gears to an AI with ADAT ports.

There is also the issue of feeding a bog S AI from a line (Art) output? Makes poor sense to feed another attenuated mic pre and so I would suggest an AI with dedicated line inputs. Since you are SO concerned about latency do investigate the Native Instruments KA6, lowest latency you will get under £200. Plus, you get 2 mic pres, MIDI and the S/PDIF I/O you wanted. Six track capability for under £200!

Mind you, IF I was younger and starting again I would save for an RME UCX!

Dave.
 
ADAT doesn't have to transmit 8 channels. In fact most of the time in the home studio world as soon as you want to go above 48k audio you lose some channels.

anyhow, yeah OP just pick up a cheap audio interface. That scarlet you picked out seems like a solid choice.

Most small interfaces defeat latency by utilising input monitoring instead of piping it through your PC first (there will be a knob that mixes the PC audio playback and the input sound so you can blend them when overdubbing). Latency is then (in almost all daws I have ever heard of) compensated for by the DAW when writing to track.
 
Guitargodgt said:
ADAT doesn't have to transmit 8 channels. In fact most of the time in the home studio world as soon as you want to go above 48k audio you lose some channels.

anyhow, yeah OP just pick up a cheap audio interface. That scarlet you picked out seems like a solid choice.

Most small interfaces defeat latency by utilising input monitoring instead of piping it through your PC first (there will be a knob that mixes the PC audio playback and the input sound so you can blend them when overdubbing). Latency is then (in almost all daws I have ever heard of) compensated for by the DAW when writing to track.
Click to expand...

Yes, I quite understand that ADAT can run fewer than 8 channels but if it is only two, why call it so? In any case AFAIK "ADAT" is a slightly different protocol from S/PDIF so if OP wants to use it he needs an ADAT equipped interface. He certainly seems to want to use S/PDIF and the low rent F'rites do not have that.

Dave.
 
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