Latency

I'm a novice at the use of virtual instrument in audio production.  I came from the dedicated MIDI world :)
 
Here's my current setup:
 
Roland RD-300NX
 
Processor: Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz 3.39 GHz
Installed memory (RAM): 16.0 GB
System type: 64-bit Operating System, x64 based processor
 
Windows 8.1 Pro
SONAR Platinum Update 5
Sound Card: Creative Technology Sound Blaster Z
 
Note: I'm using only the virtual instruments for my production.
 
Questions.
1. Do I have adequate hardware/software to get the lowest latency?
2. What should I purchase/replace to get the lowest latency?

you need to have a soundcard/interface that uses ASIO drivers to get a low latency setup.
like Mudgel advised check what you need in terms of instrument you'll be using.
Cakewalk & Roland have affordable interfaces and ofcourse that's a good choice to have trouble-free operation.
Akai EIE PRO (the silver box, not the red one) is known for lot of options/low latency at affordable price but there's so many 
good sound cards/interfaces out there..
Spending more, you could look at RME fe.
 
Apart from the Sound Blaster your setup is up to date / good.

>Questions.
>1. Do I have adequate hardware/software to get the lowest latency?

As Mike mentioned above, Creative Sound Blaster card is not suitable for DAW / low latency.

>2. What should I purchase/replace to get the lowest latency?
 
- Turn off wireless network, run the latency checker : http://www.thesycon.de/deu/latency_check.shtm
 
- get an audio interface for DAW, some starting point (lower price / input - to higher price / inputs/features)

http://www.sweetwater.com/store/detail/ScarlettSolo
 
Edit : ScarlettSolo do not have MIDI (ok if you already have other USB midi input, but if you only have 5-pin midi connector, look for an interface with MIDI in/out)
 
http://www.sweetwater.com/store/detail/QuadCapture
 
http://www.sweetwater.com/store/detail/UltraLiteAVB
 

rgturner
2. What should I purchase/replace to get the lowest latency?

As others have said, the Creative card is the weak spot in your setup.

You may not need the lowest possible latency, but you will need latency so low the delay between playing the controller and audio coming out of the computer is low enough that you don't notice it. That is for most people latency under 10 milliseconds, but some of us find we need lower than that.

If you are only going to be using VSTis and not recording audio or won't need more than a couple of inputs then that will help bring the price down. It might be a mistake to get an interface that's only just adequate for your needs though. You may find later on that you do want more inputs, either microphone or line level. If you have hardware synthesisers for example, you might find they still have their uses. Many people still use "real" synths, myself included.

For low latency performance much depends on not only the hardware but the quality of the drivers. The manufacturer's record of releasing new and good ASIO drivers for their older hardware is also important. You don't want to spend a lot of money on an interface if the manufacturer has a history of dropping driver support for new versions of Windows.

Interfaces made by RME have a very good reputation for low latency and good driver support. The newer MOTU interfaces are well regarded, as are the higher end of the Focusrite range. Avoid interfaces that rely on USB power alone and don't have an external power supply. Personally I would avoid using a firewire interface with Windows as they can be problematic due to less than ideal firewose support in Windows. A firewire chip made by Texas Instruments is pretty much essential to get firewire to work as well.

For an interface with very good latency and only a few inputs and outputs the RME Babyface is highly regarded, but much depends on how much you want to spend.

Avoid using ASIO4ALL as a driver if you possibly can. It works for some people, doesn't for others and can interfere with manufacturer's ASIO drivers. Some people on other forums seem to tell everyone that ASIO4ALL works miracles and is the driver to use no matter what the interface. It isn't.

Recently I was making up my mind on this very subject: http://forum.cakewalk.com/Tips-on-buying-correct-audio-interface-m3257050.aspx
And I decided to throw away my sound blaster and buy Scarlett Solo, with which I am very happy with the current latency.
Now I have up to 155 samples with 48000 Hz (3.2 msec).