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What should someone be looking at in terms of a Music Interface i.e. an input/output board that could be connected to a G5 or the new Powerbooks? Which brands are the best? What are the specs you should look for?

Cheers,

RtC
 

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Depends what you mean by "music". I assume you're talking about "audio" - but maybe you are also interested in MIDI.

Your question is very general - but this is not a criticism. I would just say - consider what exactly it is you want to be able to do. Then all you have to do is find the boxes that offer that/those specific option(s) - and then compare them.

Also - my personal advice is not to dwell on specs. Sound quality is subjective. Try stuff out at your favourite music store... listen for distortion, noise and crosstalk/interference. if a box sounds good - and WORKS - then add it to your list of possibilities.

However, one spec that is definitely worth noting - especially if you're planning on using software synths or doing multitrack recording/overdubbing - is "latency".

http://www.digitalprosound.com/Htm/Articles/April/Audio_Latency.htm

As for the G5 - it comes with a built-in stereo digital (optical) interface which should be great for i/o if you don't need more than 2 inputs and outputs. All you really require is an A/D/A (analog/digital) converter box.

http://www.apple.com/ca/powermac/expansion.html

For this purpose (A/D/A) I use a MindPrint DI-Port - which is very good quality and extremely handy. It has a couple of pretty good mic preamps and can also be used for remote recording by plugging it into a DAT recorder (or anything else analog or digital).

http://www.musicmarketing.ca/products/mp_diport.html

If you are using a digital receiver to power your speakers, then it probably has an optical digital port (TOSlink) into which you could plug the G5 directly (maybe the G5 port will also be capable of delivering an AC3 or DTS digital surround signal?). So maybe all you need is something for input - an Analog to Digital converter.

If you feel you require more inputs or outputs or both - then I would suggest a firewire interface like the M-Audio 410 (4 in 10 out) which also has 2 mic preamps - and MIDI i/o for about CAN$550. A pretty complete solution.
http://www.m-audio.com/products/m-audio/fw410.php

The "Mobile IO" is worth looking at...

http://www.mhlabs.com/mobileio/

and Mark of the Unicorn also make a variety of firewire and PCI solutions.

http://www.MOTU.com

PCI card interfaces tend to deliver higher performance (lower latency, DSP) although firewire is closing - or has closed? - the gap. If you are working with video AND audio (ie soundtrack for picture) then it I find it effective to dedicate the firewire bus to the video stream and use PCI for audio. This seems to distribute the load across computer resources more evenly - and things tend to run more smoothly. May not be as much of an issue in a G5.

If you decide to go for a PCI card interface (not an option with a powerbook), make sure it is compatable with the G5 PCI slots (which are a different voltage than previous Macs) and make sure there is no A/D or D/A on the card itself. Conversion should instead take place in a "break-out" box - external to the computer chassis. If analog conversion occurs INSIDE the computer (ie on a PCI card) your audio is likely to be affected by electronic radiation. Also, chords carrying analog signals to and from your computer are likely to pick up interference along the way unless you take pains to isolate and sheild them from all the other chords: power, video, USB, ethernet, firewire, etc. Not recommended. Digital connections - especially optical - are not so susceptible.

There are also PCI cards that offer i/o and DSP along with software effects and synthesizers which utilize the DSP on the card. With a G5 i don't consider it is necessary to purchase more DSP - and a powerbook has no accommodation for PCI cards. So - not recommended unless you have a tower and desire those particular plugins and synths.

If you require MIDI input, and MIDI is not included in any audio interface you may pruchase - then you may be looking for a USB MIDI interface or USB keyboard. M-Audio makes an interesting little gadget called "Ozone" which is a USB interface, keyboard, MIDI controller and audio interface (with mic preamp) all-in-one (great for going on the road with a powerbook - but only if you don't play with more than one hand!). They also produce the Evolution line of keyboards - and the kbds from Edirol are supposed to be pretty good too.

Well - I guess this could go on for ever... sorry ... but I'm just getting started! There is a lot of choice and you must pick the box(es) that best suit(s) your particular needs. Here's a link to a webtailer with a fairly comprehensive list of equipment, prices (U$) and descriptions - and even some reviews:

http://www.audiomidi.com/hardware/index.cfm

hope this is helpful. + Happy hunting.

[ September 21, 2003, 02:14 PM: Message edited by: vacuvox ]
 

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Heyas,

That's a pretty open question, and in order to provide info about specs and brands you should be a little more clear about exactly what you want to do with the music interface (no disrespect intended). Are you transferring your vinyl collection to your HD? Are you making tracks in a program like Reason or Live? Are you recording a string section with a huge whack of microphones? Do you need features such as surround playback capability and full duplex recording/playback? Do you need MIDI? How portable do you require your interface to be? What is your budget?

There exists a huge variety of music interfaces for the Mac covering the entire spectrum of prices and capabilities, any of which are decent purchases depending on what exactly you want to do with them. You have to give a little more information in order for me (or someone else) to give you a specific recommendation.

Again, no disrespect intended, but I hope that this post gives you an idea of what other information is needed to adequately answer your question.

FWIW, rich.
 

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The G5 has S/PDIF digital in/out on the mobo; this supports up to 8 channels in/out.

The G5 has 2-channel analog audio in/out.

With both the analog and digital in/outs, up to 24 bit/48Khz is supported.

OSX's core audio supports 24-bit audio natively.

Right there, you have 90% of what most add-on PCI cards provide in G4 or earlier models.

I can't think of too many users who would need more than that; and I'm sure if you do, you already know enough to decide what PCI card offers the missing bits.

The only thing on my wish list that the G5 doesn't provide is support for sample rates of 96 and 192Khz. (96 Khz support is partly supported on the G5 but only when the internal word clock can be employed).

It also appears that the G5's built-in audio may be limited if you need simultaneous DSP support (ie using all the analog and digital in/outs simultaneously).

For the most part, very few users would even come close to taxing the G5's audio support. If you're not into some serious content creation, everything you need is pretty much there out of the box.

The only thing that remains to be seen is the subjective quality of Apple's AD/DA converters. For that we would need to use one and put the test to our ears. However, I would be very suprised if the G5 wasn't the equal of most of the $200 or so add-on cards available today with the same in/out abilities. It is without a doubt the best built-in support Apple hardware has ever had for sound.

Although I prefer Coaxial S/PDIF over optical, the optical interface does a better job of eliminating some noise (it's immune to ground loop hum, for example).

Vacuvox has provided a (very) comprehensive answer. In particular, you will need to consider everything he said, and more, if you plan to use a Powerbook.

I can't comment on MIDI support on the G5, but I can say that it's very likely that latency will not be a problem with the built-in audio of the G5; most add-on soundcards had their latency performance instantly improved to near-neglible levels when OSX's Core Audio support replaced OS9's methodology.

I guess what I'm really saying is if you run a G5, wait until you've put it through it's paces before you consider an add-on card. You may well find you can keep the money in your pocket, something serious audio users wouldn't have considered possible with a G4 or earlier.

[ September 21, 2003, 07:44 PM: Message edited by: gordguide ]
 

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Thanks for the nod Gordguide... :cool:

I concurr about putting the G5 through its paces before purchasing additional equipment (although, in order to exploit the built-in digital i/o, some sort of A/D/A is required).

I didn't intend to overlook the built-in analog i/o - but I guess I did systematically disregard it. This is because I have never found it satisfactory in previous Macs. Maybe the G5 analog circuitry will turn out to be higher quality and better shielded than Apple has seen fit to provide in the past... but I'm not holding my breath. Also i suspect that the analog and digital i/o are mirrored - rather than independent. However - I haven't seen this stated anywhere.

and... i'm going to challenge your opening statement.


According to EMAGIC (owned by Apple):

"The (G5's) built-in Toslink optical digital audio I/O complies with the S/PDIF protocol. This interface allows the exchange of audio data in stereo or 5.1 surround sound (at a 24 Bit/48kHz sample rate, as used in DVD movies) without any loss in quality."

I believe only the ADAT optical standard supports 8 channels of digital audio. The SPDIF output of the G5 is geared towards stereo and surround sound applications rather than multiple discreet audio feeds. Also, i haven't seen anything yet that suggests the G5 can receive more than 2 channels.

My RME card allows switching of its optical ports between ADAT (8) and SPDIF (2) - but I haven't read anything yet that suggests the G5 supports or will support the ADAT optical standard. Don't know what the possibilities are there. Hope I'm wrong! ;)

[ September 21, 2003, 10:19 PM: Message edited by: vacuvox ]
 

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For the curious: The ADAT propretary interface was designed by Alesis Corportation to handle 8 channels. Where it differs from S/PDIF (Sony/Phillips Digital InterFace) is in it's ablilty to sync with a number of other ADAT machines (ie if you had 2 machines, you could use 16 tracks and the machines themselves would play back or record in unison; each machine can handle 8 tracks, maximum). In the old days, you would be limited to whatever number of channels your tape deck could handle (maximum of 24). In the late 70's some clever people figured out how to electonically lock 2 tape decks together, so we had 48 and eventually 96 channel recording. ADAT is like a digital version of those locked tape decks, 8 channels at a time.

S/PDIF doesn't automaticlly sync, but it does handle the same size bitstream.

And, no, I don't see anything about the ADAT standard on the G5.

However, a single S/PDIF in or out can handle up to 8 channels of audio. Thus the 6.1 (6channels plus 1 bass channel; total of 7) and 7.1(7 channels plus 1 bass channel; total of 8) systems that some Home Theatre systems can play back; in each case a single S/PDIF output drives the system.

I think Apple talks 5.1 because the next version of Apple's DVD player software will support 5.1 playback. However, S/PDIF can pass up to 8 channels of audio; with the right video software, for example, you can do 7.1 mixes on one S/PDIF interface. In other words, it's not hardware-limited to 5.1. So, I would be suprised if there is a 6 channel limit instead of 8.

Apple's docs on the G5 at ADC indicate that you must choose either digital or analog in, but it plays back simultaneously.

It plays back because all digital audio is sent via the controller chip to both to the S/PDIF out and the D/A conveter. The D/A converter feeds 5 separate analog amplifying circuits simultanously: 2 channels to the line out; 2 channels to the headphone out, and 1 summed to the internal speaker.

Also interesting, is that the ADC docs indicate that all audio is handled internally as 32-bit floating format, and the audio subsystem is self-contained, requiring zero CPU processor cycles.

To vacuvox: hello from a fellow RME user.

[ September 22, 2003, 11:05 AM: Message edited by: gordguide ]
 

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Thanks for clearing that up GordGuide...

um... RickTheChemist? you started this thread - any comments? we're working up a sweat here


In any case - nice to see Apple finally upgrade the built-in audio capability of their machines!
 

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Discussion Starter · #9 ·
You guys freaking rock dudes.. I am just asking the general question.. I am a sales rep at a local resellera and I would like to know what to recommend..

Cheers,

RtC

P.S. Keep it up.. I will have more time to dweel on exactly what you guys are saying here later..
 

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I hope you'll pardon my following up a year-and-a-half after this thread went dormant, but you guys touched on a couple of points regarding which I haven't been able to find hard data elsewhere.

I've a G5 tower with SPDIF Toslink optical I/O that I'd like to use as my primary external interface. I'm already running amplified speakers off the optical outputs, and since I intend to handle all my signal processing natively I really only need a good set of A/D inputs to get stuff in from the real world.

Gordguide, you posited some interesting specifications regarding SPDIF's 8-channel capabilities. I'm not sure if I'm understanding you correctly, though - when you say that it handles the same size bitstream, does that mean that SPDIF input can ignore ADAT sync and read the audio signal coming off a lightpipe connection?

Or are you merely pointing out that, if equipement supports it, an SPDIF connection is capable of 8 channels within its own format? All the SPDIF Toslink A/D equipment that I've found seems geared toward 2-channel connections, but maybe I haven't been looking in the right places.

On a tangential note, in reading through my G5's optical digital audio input specifications I see that while it lists external clock mode sample rates of 32, 44.1, and 48 kHz, it also lists internal clock mode sample rates from 16 to 96 kHz. Am I correct in understanding that if external sync isn't an issue for me, I could input 24/96 SPDIF signals? I'm note sure that I properly grasp the distinction between internal and external clock modes.

In whatever case, so far it's appeared that my best option would be something akin to ART's <a href="http://www.artproaudio.com/products.asp?cat=1&id=48&type=79&show=Overview">Digital MPA</a>, a Toslink SPDIF stereo A/D with built-in microphone preamps. If I could attach ADAT lightpipe connections to my Toslink SPDIF input, though, that opens up a lot of other possibilities - ranging from a higher-quality stereo A/D like Universal Audio's <a href="http://www.uaudio.com/products/digital/2192/specs.html">2192</a> to something like M-Audio's 8-channel <a href="http://www.m-audio.com/products/en_us/Octane-main.html">Octane</a>, either of which could be supplemented by external microphone preamp channel strips as needed.

I'd sure like the freedom to attach the latter, but everything I've read implies, but doesn't state definitively, that I'm limited to the former. I'd really like to stick with the G5's built-in audio options in order to keep my few PCI slots free for DSP cards and dedicate my firewire ports to external hard drives. Since you guys (gordguide and vacuvox) seem more familiar the idiosyncrasies of trying to use the G5's built-in Toslink SPDIF connections than any other references I've perused, I'd greatly appreciate any pointers. Thanks!
 
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