External Audio Interface and Notion

[GeorgePaul]

Hi y’all ! I have recently contacted Tech-support regarding the use of NOTION on stage to back up live bands. I would like to hear your opinions.

Original message to tech support:

I use Notion mainly to back up a 15 piece band on stage during live concerts.
Would it make a difference (regarding sound quality) if I use this http://www.apogeedigital.com/products/duet2.php or this http://www.motu.com/products/motuaudio/microbook instead of the Macbook Pro’s built-in audio card?

If your answer is YES, which one would you recommend?

Cheers !

[Surfwhammy]

Hi y’all ! I have recently contacted Tech-support regarding the use of NOTION on stage to back up live bands. I would like to hear your opinions.

Original message to tech support:

I use Notion mainly to back up a 15 piece band on stage during live concerts.
Would it make a difference (regarding sound quality) if I use this http://www.apogeedigital.com/products/duet2.php or this http://www.motu.com/products/motuaudio/microbook instead of the Macbook Pro’s built-in audio card?

If your answer is YES, which one would you recommend?

Cheers !

The MacBook Pro probably has an onboard Intel audio processor, which is good, and Apple specifically requires Intel to add custom capabilities and features to the Intel processors that are used in Apple computers, but there are advantages to using an external digital audio interface . . .

I use a MOTU 828mk3 Hybrid digital audio interface, as well as a MOTU 828mkII digital audio interface, Digital Performer 7.24, and MachFive 3, and I like MOTU products, in part because their primary focus is the Mac, although more recently they are focusing on Windows, as well . . .

The advantages of an external digital audio interface like the MOTU MicroBook II are (a) that it has balanced line outputs and (b) it does some of the audio processing, which at least in theory reduces the workload of the onboard processors and hardware of the MacBook Pro . . .

However, using an external digital audio interface changes the hardware configuration, which can have consequences, since for example instead of using Core Audio and the onboard audio hardware of the MacBook Pro exclusively, you are using a blend of technologies, onboard and external . . .

Based on what I know about studio work--as contrasted to live performance work--I would use the MOTU 828mk3 Hybrid, but I am a bit reluctant to suggest anything specific to live performance work, because while I have experience playing electric guitar, electric bass, and singing in live performances, as well as doing sound reinforcement work, I do not have any experience using NOTION 3 for live performance work . . .

Hence, I think the best strategy is to follow the advice from the Notion Music folks, because they do this type of live performance work in their NOTION Live service, and this makes them experts in this arena, which is fabulous . . .

NOTION Live (Notion Music)

Fabulous!

Nevertheless, a bit of common sense and an understanding of the basic principles of electromagnetism indicate that there are limits to the ability to use an unbalanced high-impedance audio cable, even for a short distance due to noise and radio interference problems, so it is virtually guaranteed that the standard strategy is to get the output of the computer into a professional quality digital audio interface via FireWire, Optical, or USB as early as possible and then to use balanced systems and cables to move the audio over longer distances, hence I am comfortable recommending MOTU products, because (a) MOTU knows and understands the Mac intimately and (b) you actually can call MOTU Technical Support and get specific advice on configuring and using MOTU products, for sure . . .

For sure!

[GeorgePaul]

Thanks Surfwhammy !
I did some research and found a few posts, one old and two more recent regarding MOTU and Apoggee. Take a look if you wish please.

http://www.gearslutz.com/board/music-co ... pogee.html

http://recording.org/pro-audio-gear/518 ... pogee.html

http://www.gearslutz.com/board/music-co ... alite.html

[Surfwhammy]

Thanks Surfwhammy !
I did some research and found a few posts, one old and two more recent regarding MOTU and Apoggee. Take a look if you wish please.

http://www.gearslutz.com/board/music-co ... pogee.html

http://recording.org/pro-audio-gear/518 ... pogee.html

http://www.gearslutz.com/board/music-co ... alite.html

Glad to help!

When considering the value of information in FORUM discussions, it always is helpful to look at the dates when posts were made, since everything in digital music production tends to change rapidly over time, so that something which might have made sense five years ago might make no sense today, although it depends on the specifics and what is being discussed, of course . . .

This is an YouTube video of an audio workshop Ethan Winer (Real Traps®) hosted in 2009, and it provides a few clues to the best way to put audio information into perspective . . .

Audio Myths Workshop (Ethan Winer) -- YouTube video

Real Traps®

In the late-1980s and early-1990s, Ethan had a company (Crescent Software) that developed software engineering tools for Windows, which is where I met him, since around the same time I had a company that provided one of the first Windows database tools, and he is an interesting fellow, for sure . . .

For sure!

But his true passion is music, and he switched his focus to music in the 1990s, where among other things he decided to study cello and over the years has become an accomplished cellist . . .

Curiously, I did something similar over a decade ago, and once I discovered that Ethan had switched his focus to music, I thought it was a patently surreal "coincidence", but it makes sense when you understand that musicians tend to be excellent software engineers, in part because musicians are accustomed to being able to manage complex dynamically changing activities in real-time, as well as to be aware consciously of multiple simultaneous events and intricate interactions (for example, the various instrumental parts in a song, symphony, or film score), all of which is intimately time-based, which for transaction-based operating systems like Mac OS X and Windows are truly valuable skills, which from this perspective makes developing applications very similar to composing music and conducting an orchestra or musical group . . .

For reference, the way I discovered Real Traps® was by doing some research on studio designs when I was designing the sound isolation studio, which is a room within a room within a room, where the intermediate room sits on a fully floated floor of rubber mats made from ground truck tires, which is the low-cost way to float a floor, where "float" in this context refers to the floor not being physically attached or connected to the subfloor upon which it sits, which is important because, for example, a single nail or metal screw can transmit a rather surprising amount of acoustic energy, as is the case with a hole in a wall or ceiling with a diameter as small as 1/8th of an inch, with the general high-level rule being that acoustic energy when anthropomorphized does not like to travel through multiple layers of material that have varying densities, with an example being that you get better sound isolation by covering a wall (a) with a sheet of gypsum board which is 1/2" thick and then putting another sheet of gypsum board which is 5/8" thick on top than (b) with two sheets of gypsum board both of which are 1/2" thick . . .

Yet another useful bit of information comes from blowing across the top of a soda pop bottle, which in acoustic physics is a "Helmholtz Resonator", which is something that the ancient Greeks and Romans understood and used to adjust the acoustic behaviors of their theaters, where they embedded large wine bottles in the walls and partially filled the bottles with sand to fine-tune the listening rooms, and while the algorithms for determining the proper hole diameter are a bit complex, doing experiments with different sizes of bottles is a good way to discover the rules, where one of the things I did in the design of the floors, walls, and ceilings of the sound isolation studio was to add layers of absorbing material that was fully enclosed in plywood but had a few small diameter holes, although there also are fully enclosed subsections with no holes, as well as air spaces of varying widths between the walls and ceilings, where among other things you can run a Stihl chain saw in the sound isolation studio with all the doors closed and someone in an adjacent room but perhaps 20 feet away cannot hear the chain saw, and vice-versa, which is a bit mind-boggling, really . . .

Helmholtz Resonance (wikipedia)

Really!

The practical perspective is that when you run NOTION 3 generated audio through sound reinforcement system (amplifiers and loudspeakers, if you prefer), the most important thing is that noise is kept to a minimum, where in this context "noise" is defined to be unwanted or undesired sounds, which is a different focus from the typical focus in the audiophile universe and is explained in the latter part of Ethan Winer's audio workshop video (see above) . . .

More to the point, the current fact is that NOTION 3 generates audio at standard CD quality (44.1-kHz at 16-bits), which makes higher resolutions not only silly but actually detrimental in the digital universe . . .

My perspective is that both of the external digital audio interfaces you are considering probably sound very nice, and by the time you run the audio through an amplifier and loudspeaker system any subtle differences simply do not matter, where as noted the primary concern is that the various equipment be what one might call "electromagnetically quiet", which certainly is a vastly important consideration, since among other things one typically has less control over the way performing venues are wired and so forth and so on, where for example "ground loops" can be a major problem, although there are various strategies for dealing with them . . .

Yet another consideration involves the perspective of the long run, where it becomes important to have a plan for the future, since especially in music the general tendency is to get a lot of less expensive products on the spur of the moment based on the idea of "saving money", but what usually happens is that people get a lot of "inexpensive" products repeatedly and the total cost over the long run is greater than getting a professional quality product in the first place, which is something I realized after getting a virtual festival of nice but expensive electric guitar effects pedals and devices over several years and then discovering AmpliTube (IK Multimedia), where the reality was that I spent more than enough money on the virtual festival of electric guitar effects pedals to have purchased a Mac Pro, a MOTU 828mk3 Hybrid, AmpliTube 3, and a Stealth Pedal CS (IK Multimedia) complete with all the additional hardware, but this is fine with me, since I learned how to use everything, and some of the effects pedals do things which are unique (for example, the DigiTech Whammy pedals) . . .

My experience over the past decade with MOTU products is excellent, and I value the ability to call MOTU Techincal Support to get help when I simply cannot discover how to do something . . .

And on a related note, there is a reason that the MOTU MicroBook II has a fully enclosed metal case, which is that it functions as a Faraday shield . . .

Faraday Shield (wikipedia)

MicroBook II (MOTU)

If you have an iPad, then there is another reason to consider getting one of the MOTU external digital audio interfaces, which includes the MicroBook II, which specifically is that you can control CueMix FX with an iPad via WI-FI, which is intriguing . . .





Wireless control of CueMix from your iPad (MOTU)

TouchOSC (hexler.net)

Nevertheless, I continue to recommend getting some advice from Notion Music on what is most practical for using NOTION in live performances . . .

Lots of FUN!

P. S. For approximately the same cost as a Duet 2 (Apogee) and its "breakout box", you can get a MOTU 828mk3 hybrid using the current "FALLSAVE" discount promotion at Musician's Friend, and you can get a small 4-space rack case for approximately $80, and in this scenario I strongly recommend using a Tripp-Lite ISOBAR surge protector (a personal favorite), which is an excellent way to protect your investment, really . . .



MOTU 828mk3 Hybrid



ISOBAR6 (Tripp-Lite)

Really!

[GeorgePaul]

Great post Surfwhammy !

I knew about Ethan from his video Cello Rondo http://www.youtube.com/watch?v=ve4cBOnSU9Q
which I think is fabulous and besides being a great musician he is clearly an expert regarding sound technology.

Surfwhammy wrote:
More to the point, the current fact is that NOTION 3 generates audio at standard CD quality (44.1-kHz at 16-bits), which makes higher resolutions not only silly but actually detrimental in the digital universe . . .

Funny, I keep hearing from Notion Support (Since version… 1. something...) I could get better sound quality out of an external audio interface rather than using the laptop's built-in card. In fact a couple of years ago following their advice I tried out a FAST TRACK M-AUDIO external interface. A group of colleagues and I all agreed that there was not difference regarding sound quality at all.

This weekend I will have the opportunity to try out the Apogee’s DUET2. Lets see how it goes.

Cheers !

[Surfwhammy]

I keep hearing from Notion Support (Since version… 1. something...) I could get better sound quality out of an external audio interface rather than using the laptop's built-in card.

This is excellent advice, but understanding it might not be so easy . . .

In the Apple universe, which for reference in some respects will be identical to the Windows universe, what one might call "primary audio' or "onboard audio" is handled by Intel High Definition Audio (a.k.a., "Intel HD Audio"), which is fine, but as with all all hardware, firmware, and software there are levels with respect to performance, quality, and so forth . . .

Intel High Definition Audio

On the Mac, audio is handled by Mac OS X Core Audio in conjunction with the various onboard hardware and firmware, and it is possible that Apple requires Intel to enhance some aspects of audio, although Apple certainly has custom requirements for other aspects of the Intel processors it uses . . .

With the Mac Pro, audio functionality can be enhanced in two ways, as is the case for a Windows desktop or server class machine with PCI Express or similar slots and various types of external ports (FireWire, Optical, USB), but for "all-in-one" Macs enhancing is done via external digital audio interface devices like the MOTU 828mk3 Hybrid, which works with Windows machines, as well . . .

Internally, digital music production applications work with digital audio, but at some point the digital audio must be converted to analog for purposes of reproducing the audio in the analog universe of signal processors, amplifiers, and loudspeakers, and this is where the difference in onboard audio and external audio become important . . .

If you rollback the clock to the early-1950s and consider an electric guitar rig where there is a Gibson Les Paul or a Fender Telecaster played through a Fender vacuum-tube combo amp (amplifier and loudspeakers), then this is purely analog, because there were no solid-state devices at the time other than perhaps in research laboratories, where as I recall the "transistor radio" did not become ubiquitous in the US until the late-1950s, at which time it was the equivalent of an iPod, even though transistor radios only played AM radio stations and were monaural . . .

Over the next few decades, solid-state devices became more prevalent, but there continue to be significant differences in solid-state power amplifiers and vacuum-tube power amplifiers, although it is not uncommon for a vacuum-tube power amplifier to have solid-state rectifiers, but so what . . .

So what!

The computer (Mac and Windows) works with digital audio, where the sound is represented by binary bits, but when it is time to reproduce the sounds in the physical world, the digital audio information needs to be converted from digital to analog, which is the reverse of what happens when the analog output signal an analog device like a microphone or electric instrument is digitized, where the analog output signal is converted to a digital signal . . .

By convention, analog-to-digital is abbreviated as "AD", and digital-to-analog is abbreviated by "DA", so for example if you want to get the analog output signal from a passive electric guitar into a computer, then you need an AD converter, and similarly if you want to use the digital audio from a computer to feed analog devices, then you need a DA converter, which from a practical perspective is one of the roles of what I call "external digital audio devices" like the MOTU 828mk3 Hybrid, since these types of devices provide AD/DA converters, as do PCI Express sound cards and so forth . . .

There are different types of AD/DA converters, where some are lower resolution and others are higher resolution on the digital side, and on the analog side there also are different implementations and technologies with respect to high-fidelity and other considerations, where one very important aspect involves balanced and unbalanced analog signals, where balanced analog signals map to the lowest noise, and the two most common strategies are TRS (Tip, Ring, Sleeve) and XLR, but impedance also is a key factor, and low-impedance devices like some high-quality studio microphones require preamplifiers and in some instances "phantom power" for the microphones . . .

Electric guitars with passive pickups and circuits nearly always are are high impedance devices, and in some scenarios it is possible for the electric guitar, guitar cord, and amplifier to function as an AM radio player, and in some instances a vacuum tube will behave as if it were a microphone, which is a clue that the vacuum tube needs to be replaced, among other things . . .

[NOTE: In the early-1970s, Gibson made a low-impedance Les Paul guitar, which was intriguing . . . ]



And then there is the matter of everything in the analog universe being interdependent, where instead of everything being a set of one-way "pipes", the "pipes" typically are at least somewhat two-way, which affects the way everything works . . .

If you consider only the size and weight of a MacBook Pro and a MOTU 828mk3 Hybrid, it should be obvious that they are similar, which then raises the question, "Why?" . . .

Part of the reason is that the MOTU 828mk3 Hybrid has a virtual festival of 1/4" TRS ports, as well as two XLR/TRS ports, front panel Main Output stereo and headphone jacks, and on the back panel some Optical, Digital, and MIDI ports, as well as an internal power supply, LED displays, knobs, and so forth and so on, but even then there is other stuff, and the "other stuff" is focused on AD/DA conversions . . .

The problems with using the built-in output of a MacBook Pro, iMac, Mac mini, or Mac Pro are (a) that it is analog and (b) that it is unbalanced, although it is shielded . . .

The difference in "balanced" and "unbalanced" is that for example a 1/4" TRS to 1/4" TRS cable has two conductors and a ground shield, so that when the signal is balanced monaural, the two internal conductors carry signal and the ground via Tip and Ring, but the two internal conductors additionally are shielded by the outer metal ground shield (a.k.a., Sleeve), but when the same connectors and cable are used for stereo, then the inside two conductors carry the left and right channel signals, respectively, but they share the common outer ground shield, which makes it "unbalanced", where the important consideration is to have the signal traveling in both directions but inside a common outer grounding shield, since by having the signal going in two directions, this causes external noise, interference, and so forth to cancel, which makes everything very quiet . . .

With the MOTU 828mk3 Hybrid, the "stereo" output actually is a pair of balanced 1/4" TRS ports, where one port is the left channel and the other port is the right channel . . .

There also are difference in the quality of the DA converter hardware, firmware, and software, where in the external digital audio interface strategy, the idea is to send the digital information from the computer to the external digital audio interface, where the DA conversion for output is made in the external digital audio interface using what in nearly every instance are higher quality components . . .

Whether it is possible actually to discern the difference in quality is another matter, and it is highly dependent on a variety of factors, where for example if the amplifier is a solid-state device and is a class D amplifier, then one should not expect the same listening experience as when the amplifier is a solid-state device but instead is a class AB amplifier, and there also is the matter of the loudspeakers and their characteristics, including frequency range, as well as the way the entire audio reproduction system is equalized and calibrated . . .

With the same set of loudspeakers, there will be difference if the amplifier is solid-state class AB, solid-state class D, or vacuum-tube based, and there are other solid-state classes . . .

Explained yet another way, if the amplifiers and loudspeakers are incapable of reproducing the analog signal with high fidelity, then there might be no easily discerned differences, but this does not imply that there are no differences. Instead, it only implies that the amplification system is not so good, which effectively blurs the actual differences . . .

But, as explained with examples in the Ethan Winer's audio workshop YouTube video, some of the differences are not so easily perceived, where for example in the real world, the differences among 16-bits, 18-bits, 20-bits, 22-bits, and 24-bits are not so obvious when other stuff is happening, which is one of the reasons that standard CD quality is 44.1-kHz at 16-bits . . .

By the time the volume in the listening room is in the range of 85 dB SPL, nobody easily can determine much of anything in a very detailed way, and for nightclubs and similar venues this is not an unusual volume level and in fact probably is bit low . . .

However, 85 dB SPL is the preferred sound pressure level for final mixing and mastering, at least here in the sound isolation studio, for a variety of reasons, most of which are explained in my ongoing topic in the IK Multimedia FORUM, which is focused on affordable full-range calibrated studio monitor systems, which is fabulous . . .

The Fabulous Affordable Studio Monitor System Project (IK Multimedia FORUM)

Fabulous!

[Surfwhammy]

I did a bit of checking at Musician's Friend and noticed that there are two Akai external digital audio interfaces which look to be very intriguing, since they have more inputs and outputs, as well as MIDI ports, where the lower resolution model currently is priced at $199 (US) . . .




Akai Professional EIE I/O Audio/MIDI Interface With USB Hub

The only problem is that the highest resolution is 44.1-kHz at 16-bits (standard CD quality), which is fine for NOTION 3, but there is a professional version that does 24-bits, and increases the set of sample rates to {44.1-kHx, 48-kHz, 96-kHz}, and it currently costs $249 (US), which makes it the smarter strategy . . .


Akai Professional EIE PRO 24-bit Audio/MIDI Interface with USB Hub

However, I have no idea regarding the overall quality, but I like the way these units look and the additional inputs, outputs, MIDI ports, and USB ports, however this YouTube video provides some clues . . .

[NOTE: The VU meters change color to red when there is clipping, which is totally awesome. This YouTube video review is done on a Windows machine, but the device also works on the Mac, as you can verify in some of the other YouTube review videos . . . ]

Akia EIE Pro Review (RainComputersUK) -- YouTube video

And this brings up yet another consideration, which is the speed of the external digital audio interface with respect to latency, where for reference there is enough latency with the MOTU 828mk3 Hybrid here in the sound isolation studio that I use direct monitoring when singing, but this might be due to my being a bit more sensitive or perceptive with respect to rapid echoes, which is what happens when there is even a tiny bit of latency above perhaps 5 to 10 milliseconds, where for reference the Haas Effect occurs with a delay as low as 5 milliseconds . . .

Haas Effect (wikipedia)

However, while rapid echoes make it virtually impossible for me to talk or sing when recording, everything changes when I switch to mixing, where reverberation and echoes are vastly useful . . .

Lots of FUN!

P. S. I am comfortable recommending MOTU products, because I have experience with MOTU products, as is the case with Behringer hardware, although there are enough YouTube review videos on the Akai EIE Pro that I am reasonably comfortable with it . . .

And on a related note, there is more to balanced audio than just the connectors (TRS, XLR) and the ways the conductors in the cords are done, where the "more" aspect refers to the impedance of the device ports being the same, which is where the terms "line out" and "balanced" become important . . .

In reviewing my previous post to this topic, the impedance aspect was not so clear, but this note provides the additional information, although it is explained in more detail at the following link, and at present I have not been able to determine with any accuracy whether the "line out" or "headphone" ports of an Apple computer actually are balanced, but regardless there it is better to connect the computer to an external digital audio interface via either (a) a digital cable (FireWire, Thunderbolt, or USB) or (b) an optical cable and to let the external digital audio device do the AD/DA work, really . . .

Balanced Audio (wikipedia)

Really!

[Zblogny]

Let me draw your attention to an important detail :
The red one (EIE) is only USB 1.1.
Better to stay away from this obsolete standard...
So obviously the choice should be the Pro version (USB2).

[GeorgePaul]

I was not able to test the DUET2 interface after all, but in a friendly store in town they let me try a FAST TRACK form M AUDIO. They had 4 different models: Fast Track, Fast Track C400, Fast Track C600 and Fast Track Ultra 8R. It took me 30 seconds to install the latest driver (Mac OS 10.7.4.) and get it working flawlessly with NOTION. Back in my place I tested it using a YAMAHA self-powered mixer and two 13 inch speakers and could not notice any difference regarding sound quality, from the built-in sound card and the FAST TRACK.

Besides a much better performance I am so glad I do not have to use the audio jacket from the laptop anymore (the jacket has been so worn out that any small movement, even the tapping on the keyboard, unplugs the cable and activates the built-in speakers (It happened several times during rehearsals).

The only fly in the ointment is that I use a combination of Vienna Symphonic Library, NOTION and some other VST’s and when I use “PERFORM” mode in NOTION on large scores, say 30 instruments, there are sound dropouts even if I use the maximum Audio Buffer Size (1024 samples).

I wonder if using a larger interface, Fast Track C400 for instance, could solve the problem. (Paging Dr. Surfwhammy !!!)

I hope when NOTION becomes a 64 bit application these kind of problems will be over for good.

[wcreed51]

The other FastTrack models just have more input/outputs. Probably no different performance wise.