Lessons learned from researching Audio Interfaces
Posted: Tue Jan 28, 2014 5:14 pm
I am a live violin / bass / soft synth looper, and spent over two years researching audio interfaces to find the lowest latency possible for a macbook. Sadly if you *really want to know the facts about what’s out there today, you have to dig really really deep into endless forums and technical data, and even still can only infer the information that will actually make an impact on your purchase. Hopefully this will save you some time.
I'm not an expert but did spend a lot of time researching and shopping. Please feel free to tear this post apart if you feel like anything in it isn’t correct.
THE PROBLEM
I have a latest model retina macbook pro with maxed out options, and was using an old Edirol FA-101 over FW400 (FW400 -> FW800 -> TB). The lowest buffer size I could use in Live was 64 samples @ 44100, which gave me about 8-9ms round trip latency.
Despite the word on the street, this latency is not acceptable for live work. My band-mates were constantly complaining about timing. When trying to use Ableton Looper with a MIDI pedal, it is impossible to lock in the loop on time. It’s also not possible to play perfectly in sync with a Ping-Pong delay.
I only need a few channels, but am also willing to pay for quality. The goal is to find the fastest small-format interface possible.
THE STATE OF THE MARKET
Shopping for interfaces is extremely hard right now. Most reviews are several years old (2006-2008?) and on hardware that doesn’t compare with what we have today. For example, it’s extremely difficult to find hard interface latency numbers even for the very popular macbook pro / Ableton combo. Ideally we would have a professional Ableton-centric round-up of interfaces on MacBooks (or PC!).
DRIVERS
First thing: if an interface is going to be fast, it must have optimized drivers from the manufacturer. This basically includes Apogee, LYNX, RME, and some M-Audio interfaces. From tons of forum searching, I became convinced that nobody’s drivers can compare with RME. I found lots of dirt on Apogee, have so-so personal experience with M-Audio, and have found absolutely nothing but praise for RME’s speed and stability. So it seems like the choice is clear.
THE BUS
Next you have to choose a bus. We are currently in a period of minimal innovation for audio interfaces. Firewire is being phased out and USB 3.0 and Thunderbolt are starting to build momentum. USB 2.0 is plenty sufficient for say 16 channels, but USB 3.0 will make more channels available (although at the same latency as USB 2.0).
The quality of your USB chipset will affect your latency. Various tech forums report that lots of older or even current PCs are built with sub-standard chipsets, and there are enough differences to make publishing latency numbers impossible. I don't know what this is like now, but the Apple chipsets are great.
It’s also important to note that Thunderbolt is actually PCIe. Using a TB interface you can expect PCI performance but they usually use adaptors like Apogee Symphony IO + Thunderbridge ($3000 total), or RME HDSP + Sonnet Echo PCI -> TB ($1200 and up). This appears to be the ideal performance situation, but they are expensive and physically clunky.
TAKING THE LEAP
Having a macbook, the choice of USB VS Thunderbolt still remained for me. I considered going with the RME HDSP and Sonnet Echo, but couldn’t for the life of me figure out how to get the usual I/O XLR/TRS connection options found in the cheaper interfaces. So the USB FireFace UC or UCX started looking more attractive.
Plus, RME repeatedly says that their USB products compete with their PCIe products for latency, but there are no hard experiential numbers available online. Also you have to dig deep, but you will find that the RME Fireface UCX has newer AD/DA converters that are about 1ms faster than the Fireface UC, which is a big deal.
But, there is absolutely nowhere that reported on the maximum performance of any USB interface with a current computer, and this would have been the most helpful info to have. Still I took a chance and went with the UCX.
RESULTS - INTERFACE
I was really blown away with the speed and stability of the FireFace UCX over USB. I can now use Looper and play perfectly in sync with Ping-Pong delay. At a buffer size of 32 samples @ 44100, Live is reporting < 2ms round trip, and I believe it. The latency is low enough that I can’t tell the amplification apart from the instrument's natural sound until it is taken away. The TotalMix software is really incredible. The only feature I'm missing is a wifi interface and iPad app to use the UCX as a standalone mixer.
So there you have it. I would love to see others post their latencies with Live on various interface / computer combinations. That’s what I feel I was missing most in my search.
RESULTS - ABLETON LIVE
One important thing to note is that you can't really get a feel for Live's performance ceiling until you have eliminated the audio interface variable. So I will fleetingly say that Live's performance at the basics is pretty damned good. I'm controlling 7 loopers from a midi pedal with a reasonable amount of effects on each channel. I do get some audio scratches when starting Live's transport via the first Looper, but usually only when using a Max For Live device that listens to tempo changes, for example buffer shuffler. This info obviously doesn't cover all cases, but it does show that the boilerplate performance is great and the rest is up to you.
LINKS (please post more)
http://www.dawbench.com/audio-int-lowlatency2.htm
I'm not an expert but did spend a lot of time researching and shopping. Please feel free to tear this post apart if you feel like anything in it isn’t correct.
THE PROBLEM
I have a latest model retina macbook pro with maxed out options, and was using an old Edirol FA-101 over FW400 (FW400 -> FW800 -> TB). The lowest buffer size I could use in Live was 64 samples @ 44100, which gave me about 8-9ms round trip latency.
Despite the word on the street, this latency is not acceptable for live work. My band-mates were constantly complaining about timing. When trying to use Ableton Looper with a MIDI pedal, it is impossible to lock in the loop on time. It’s also not possible to play perfectly in sync with a Ping-Pong delay.
I only need a few channels, but am also willing to pay for quality. The goal is to find the fastest small-format interface possible.
THE STATE OF THE MARKET
Shopping for interfaces is extremely hard right now. Most reviews are several years old (2006-2008?) and on hardware that doesn’t compare with what we have today. For example, it’s extremely difficult to find hard interface latency numbers even for the very popular macbook pro / Ableton combo. Ideally we would have a professional Ableton-centric round-up of interfaces on MacBooks (or PC!).
DRIVERS
First thing: if an interface is going to be fast, it must have optimized drivers from the manufacturer. This basically includes Apogee, LYNX, RME, and some M-Audio interfaces. From tons of forum searching, I became convinced that nobody’s drivers can compare with RME. I found lots of dirt on Apogee, have so-so personal experience with M-Audio, and have found absolutely nothing but praise for RME’s speed and stability. So it seems like the choice is clear.
THE BUS
Next you have to choose a bus. We are currently in a period of minimal innovation for audio interfaces. Firewire is being phased out and USB 3.0 and Thunderbolt are starting to build momentum. USB 2.0 is plenty sufficient for say 16 channels, but USB 3.0 will make more channels available (although at the same latency as USB 2.0).
The quality of your USB chipset will affect your latency. Various tech forums report that lots of older or even current PCs are built with sub-standard chipsets, and there are enough differences to make publishing latency numbers impossible. I don't know what this is like now, but the Apple chipsets are great.
It’s also important to note that Thunderbolt is actually PCIe. Using a TB interface you can expect PCI performance but they usually use adaptors like Apogee Symphony IO + Thunderbridge ($3000 total), or RME HDSP + Sonnet Echo PCI -> TB ($1200 and up). This appears to be the ideal performance situation, but they are expensive and physically clunky.
TAKING THE LEAP
Having a macbook, the choice of USB VS Thunderbolt still remained for me. I considered going with the RME HDSP and Sonnet Echo, but couldn’t for the life of me figure out how to get the usual I/O XLR/TRS connection options found in the cheaper interfaces. So the USB FireFace UC or UCX started looking more attractive.
Plus, RME repeatedly says that their USB products compete with their PCIe products for latency, but there are no hard experiential numbers available online. Also you have to dig deep, but you will find that the RME Fireface UCX has newer AD/DA converters that are about 1ms faster than the Fireface UC, which is a big deal.
But, there is absolutely nowhere that reported on the maximum performance of any USB interface with a current computer, and this would have been the most helpful info to have. Still I took a chance and went with the UCX.
RESULTS - INTERFACE
I was really blown away with the speed and stability of the FireFace UCX over USB. I can now use Looper and play perfectly in sync with Ping-Pong delay. At a buffer size of 32 samples @ 44100, Live is reporting < 2ms round trip, and I believe it. The latency is low enough that I can’t tell the amplification apart from the instrument's natural sound until it is taken away. The TotalMix software is really incredible. The only feature I'm missing is a wifi interface and iPad app to use the UCX as a standalone mixer.
So there you have it. I would love to see others post their latencies with Live on various interface / computer combinations. That’s what I feel I was missing most in my search.
RESULTS - ABLETON LIVE
One important thing to note is that you can't really get a feel for Live's performance ceiling until you have eliminated the audio interface variable. So I will fleetingly say that Live's performance at the basics is pretty damned good. I'm controlling 7 loopers from a midi pedal with a reasonable amount of effects on each channel. I do get some audio scratches when starting Live's transport via the first Looper, but usually only when using a Max For Live device that listens to tempo changes, for example buffer shuffler. This info obviously doesn't cover all cases, but it does show that the boilerplate performance is great and the rest is up to you.
LINKS (please post more)
http://www.dawbench.com/audio-int-lowlatency2.htm