Sampling Rate / Latency Correlation

tenfoot
Doubling the sample rate will halve the perceived latency figure in Sonar, but your CPU has twice the workload and you will need to increase buffer sizes much sooner to compensate as you increase the number of tracks/synths.
 
For all intents the difference between 44.1 and 48 is imperceptible, and you should choose the appropriate rate for your release medium (CD, DVD etc)

tenfoot
Latency is the time it takes your system to process the audio - its round trip if you like. Generally when recording vocals and real world instruments you can monitor them directly using your interface software, so it is not such an issue. It really comes into play with soft synths and using real-time fx on inputs as you record (eg guitar fx inserts) If your asio buffers are too high, there will be a perceivable delay between playing a note on your vsti synth and hearing it.
 
The setting in Sonar is under preferences/audio/driver settings, then click on the asio panel buttonn. Generally for tracking, the lower the better. Anything above 512 samples and you will definitely be annoyed by the delay.
 
Once you have finished tracking and you are mixing and adding fx, you can increase this setting to avoid any glitching that may start to happen as you increase processor load.
 
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tenfoot
The sample setting in the asio buffer is not your sample rate. 
 
 

tenfoot
Doubling the sample rate halves the latency because the asio buffers fill twice as fast. With 1/2 the effective buffer time (there are twice as many samples for the same size buffer) than the system had at the lower sampling rate your processor will begin to feel the load much sooner, thus the need to increase your asio buffers, negating the perceived advantage of the higher sample rate.

tenfoot
Increasing asio buffers increases latency, but lowers processor load. Increasing the sample rate lowers latency (buffers fill faster) but increases system load. The end result (round trip latency) is interdependant on the two settings.

SilverBlueMedallion

tenfoot
Doubling the sample rate halves the latency because the asio buffers fill twice as fast. With 1/2 the effective buffer time (there are twice as many samples for the same size buffer) than the system had at the lower sampling rate your processor will begin to feel the load much sooner, thus the need to increase your asio buffers, negating the perceived advantage of the higher sample rate.

wait, you are talking sample rate (as in 512 or 1024 in the ASIO settings), I am talking SAMPLING RATE inside of Sonar preferences (44.1, 48, 96, etc...).
 
Which one reduces latency?

bitflipper

SilverBlueMedallion
I have been reading that the HIGHER than sampling rate, the LOWER the latency?
That sounds wrong! Wouldn't a higher sampling rate cause the hard drive and CPU to work even harder thus making latency even longer?

Yes, it sounds wrong because latency is more complicated than just how fast you shove bits into a buffer.
 
Computers can't process audio data one sample at a time. They just don't work that way. Any time we bring data into a computer it has to be in chunks, whether we're talking about recording audio or reading data from a disk drive or a network adapter. Data may come in one byte at a time, but it gets stashed in a buffer until the buffer is full, and only then is the data actually processed. How long it takes to fill the buffer is therefore the main determiner of latency. 
 
You can therefore reduce latency by either making the buffer smaller or by filling it faster. At any given buffer size, latency can be reduced by sending it data more quickly, i.e. using a faster sample rate. However, you could also achieve the same effect by making the buffer smaller.
 
Regardless of which method you use, the limiting factor is how quickly your CPU can process the data. At some point you will be feeding too much data too fast for the CPU to keep up. At that point you have no choice but to increase the buffer size, which negates the benefit of the higher sample rate, at least in terms of latency.
 
But latency is more complicated than how fast you can get data into and out of the computer. There is also the overhead of what the computer's doing to that data. Many plugins necessarily introduce additional latency due to how they work - some must accumulate data within their own internal buffers because they work on chunks of data, too. 
 
Bottom line: don't increase sample rate in order to reduce latency. Use higher sample rates because you need the wider bandwidth, e.g. songs for dogs, dolphins or bats.