I feel like this has probably been asked before, but it seems like the emphasis on software in here is too heavy anyway, so I figure, why not. I'm looking at recording some live guitar performances via my computer. I don't have a proper sound card, only Line In and Mic. (And I have no plans of actually buying a sound card, either.) The amplifier I'm using has a headphone/direct output. Is it safe to connect the amp output to my computer, and which should I use, Line In or Mic? I'm also curious about splitting the output so that I record the same performance twice simultaneously, one channel being the amped signal and the other channel being the raw output from the pickups. (I'm curious about experimenting with software VST amps and then combining that sound back with the original performance.) Is there any way to do that with the hardware I have? Any precautions, tips, etc would be appreciated as well. I don't want to damage anything, so I need to have an idea of exactly what I'm doing beforehand. The lack of real audio equipment makes it that much harder and that much more important. And, on the subject of software, FL Studio should be perfectly capable of handling all this, right?

Quote: Original post by Promit
I feel like this has probably been asked before, but it seems like the emphasis on software in here is too heavy anyway, so I figure, why not. I'm looking at recording some live guitar performances via my computer. I don't have a proper sound card, only Line In and Mic. (And I have no plans of actually buying a sound card, either.) The amplifier I'm using has a headphone/direct output.

I think I can see where this is going...

Quote:
Is it safe to connect the amp output to my computer, and which should I use, Line In or Mic?

... bingo!

VERY IMPORTANT WARNING. IF YOU READ NOTHING ELSE, READ THIS: An amplifier is there to amplify audio and make it loud. Very loud. Loud enough to drive a big, f*ck-off speaker system. That's a lot of juice. Neither of your computer's input connectors is designed to cope with anything like this load. Be VERY careful.

Right, that's the boring stuff out the way...

If your amp has a "Direct Out / Headphone" socket, that should -- please note the qualifiers in this paragraph -- be okay to connect to your computer's inputs, but check which setting it's on first. Direct output might be okay to connect to your computer's Line In, but it's likely to add some noise to the signal and I wouldn't advise it. (It's really just for monitoring, not recording.)

There are two common techniques to record live guitar. If (as I assume) you're using an electric guitar, you can either DI -- "Direct Inject" -- the output from the guitar into the computer, or you can rig a microphone in front of your guitar's amplifier and record that.

The DI technique lets you take the sound directly from your guitar -- no amplification -- into your computer. Mic connections have an amplification stage, although the 3.5" jack type don't support phantom power, so you should check the specs for your computer and guitar beforehand. Line-In keeps the sound signal as-is, but this might not be enough to 'hear' your guitar if it's a particularly quiet model. Again: RTFM. I cannot stress this enough.

DI'ing your guitar gives you a very clean sound, but it's not what you're used to hearing. You'll likely want to process the audio by running it through a virtual amplifier stage or some such to give it the right sound. This is why many opt for the second technique: stick a microphone in front of your amplifier and record that. This lets you record your amp as well as the guitar, so you can get all that grungy distortion, howl and other stuff guitarists expect to hear. (Much of the 'sound' of your guitar is really the sound of your amplifier.)

You may be able to avoid the additional microphone stage by using your amp's "Direct Output" connector, but again, this may prove quite noisy, particularly if it's an old and/or cheap amp. A decent microphone, rigged correctly -- check Sound On Sound at www.sospubs.com for some great articles on guitar recording -- can give a much better sound and also offer you more flexibility as moving the microphone just a little can make a big difference to the sound's qualities.

The _proper_ solution, in any case, is to get a decent sound card. They exist for a very good reason: The crappy components bolted onto motherboards are fine for webcams and no-hope demo tapes, but you won't get a good sound out of a Realtek AC'97 chipset no matter how hard you try. As a keyboardist, I use a Novation X-Station myself, but E-MU, MOTU and M-Audio do some nice kit as well.

As you're a guitarist, you should check out Line 6, who specialise in kit for the electric and acoustic guitar sectors. They also do a lot of stomp boxes, so you may already be familiar with their gear.

Quote:
I'm also curious about splitting the output so that I record the same performance twice simultaneously, one channel being the amped signal and the other channel being the raw output from the pickups. (I'm curious about experimenting with software VST amps and then combining that sound back with the original performance.) Is there any way to do that with the hardware I have?

Best to get a professional Y-split cable or splitter box for this. Take one output as a DI feed into your computer and send the other into the amp. Use a microphone to record the audio from the amplifier at the same time. You'll need to check if your computer's built-in audio system can cope with recording from two sources at the same time. Most don't support this, which is why I recommend buying the right tools for the job.

Quote:
Any precautions, tips, etc would be appreciated as well. I don't want to damage anything, so I need to have an idea of exactly what I'm doing beforehand. The lack of real audio equipment makes it that much harder and that much more important.

First of all: RTFM. Check the output levels of your verious plugs and sockets. NEVER send the output from an amplifier directly into your PC unless you are ABSOLUTELY BLOODY CERTAIN that you won't kill the PC.

I'm not kidding. I've seen idiots plug a 600 Watt PA amp's output _directly_ into their computer and then wonder why their computer is belching smoke and flames. And no, that's not the kind of damage your warranty will cover.

Quote: And, on the subject of software, FL Studio should be perfectly capable of handling all this, right?

The later versions should be fine with multiple-input recording chores. Earlier versions had very poor support for audio recording, so check first before spending any money.

Regards,

Plugging my guitar directly into the sound card always gives it a "warm" tone. It doesn't sound clean. I think it has something to do with impedance matching, although I'm no electronics guru by any means. You'll probably want some kind of preamp.

Quote: Original post by smr
Plugging my guitar directly into the sound card always gives it a "warm" tone. It doesn't sound clean. I think it has something to do with impedance matching, although I'm no electronics guru by any means. You'll probably want some kind of preamp.

This is why I was banging the "RTFM" drum in my previous post. Not all Line In connections are the same.

A decent pre-amp is a good idea though. I should probably have mentioned that as some microphones will need one too, which is why getting a decent sound card is usually a good idea. (Most decent microphones also require phantom power, although quite a few now allow you to provide this using a battery or by connecting via USB instead of a standard XLR audio connector.)

Many pro-level cards have very good built-in pre-amps. The pre-amp connected to the "Mic" connector on a Reaktek or similar Crapola motherboard audio chipset is likely to be crap. And very noisy too.

However, for recording guitars, I'd recommend ponying-up for either an E-MU 0404, or a Line 6.

(Oh yes: avoid Vista for now. The audio driver model in Vista has been completely changed and it'll take a few months at least before things settle down.)

Quote: Original post by stimarco
As you're a guitarist, you should check out Line 6, who specialise in kit for the electric and acoustic guitar sectors. They also do a lot of stomp boxes, so you may already be familiar with their gear.

Let me just say, the PodXT is the most amazing guitar preamp i've ever used. It's amazing for recording, or even for playing through full ranged speakers. If you want great tone, get the PodXT.

I've never used Line6 products, so I can't vouch for them. Another alternative is getting something like an M-Audio MobilePre USB, Presonus Firebox, or Focusrite Sapphire LE. All these are either USB or Firewire audio interfaces that have mic and line in jacks. The mic inputs will (obviously) have the preamp built in that will boost your signal that can be picked up by your recording software, as well as they have all have an instrument input jack, which allows you to plug your guitar directly into the recording interface and record it from there. They all have output jacks on the back so you can run the audio out to a pair of speakers that way. The price range is anywhere from $200-$300 and most come bundled with some stripped down version of pro-grade recording and sequencing software. If you do the instrument in approach, inside your sequencer (say Cubase LE), you can then route the audio through a virtual amp simulator. There's a free one called FreeAmp 2.1, which I've used a couple of times, that you can check out.

On the subject of Line 6, I got a TonePort (UX1) for christmas and the thing is AWSOME... definately worth looking into. It also comes with some recording software (Ableton Live) which is super easy to use so you can get up and running in no time.

Behringer has a relatively new product called the iAXE393 USB-GUITAR. As the name clearly suggests, it's a USB guitar that enables plugging in directly to one's computer and is accompanied by three trial versions of Native Instrument amp modelling programs. One of these may be upgraded to the full version for free upon submission of the included serial number. I haven't personally tried the guitar, but I have read a surprisingly positive review of it. Although the prices in your country may differ greatly, both the Toneport and the iAXE393 retail for a similar price. Since the iAXE393 is supposedly quite a pleasant guitar to play in itself, perhaps it's also worth looking into.

Oh, and the iAXE393 includes a copy of Audacity - for free. Isn't that just phenomenal?

Quote: Original post by stimarco
There are two common techniques to record live guitar. If (as I assume) you're using an electric guitar, you can either DI -- "Direct Inject" -- the output from the guitar into the computer, or you can rig a microphone in front of your guitar's amplifier and record that.

I did the DI thing in the past, but getting ASIO set up correctly is a bit of a fight, plus I much prefer the sounds from the modeling amp that I have (a Line 6, incidentally) over the software VST stuff.

Quote: Mic connections have an amplification stage, although the 3.5" jack type don't support phantom power, so you should check the specs for your computer and guitar beforehand.

Is this the 20db boost that Windows adds as an option, or is it something handled by the hardware itself?

I'm only dealing with a 15W amp here, and I'm running it at a small fraction of that, so I don't really expect it to be putting out that much power. Still, I don't think I've ever seen a motherboard which documents anything about how much it's prepared to accept along its inputs, which is unfortunate. I wonder if my roommate's Creative external can help...

Quote: Original post by Promit

Quote: Mic connections have an amplification stage, although the 3.5" jack type don't support phantom power, so you should check the specs for your computer and guitar beforehand.

Is this the 20db boost that Windows adds as an option, or is it something handled by the hardware itself?

That's more like just an across the board gain boost for the mic signal. Phantom power, also sometimes labeled as +48V, is designed to be transmited over the mic cable and power the internal circuitry of your microphone. As a general rule of thumb, condenser microphones require phantom power, whereas dynamic and ribbon microphones do not (in the case of ribbon mics, you can permanently damage the mic if you connect it to a jack supplying phantom power). Watch out when using that +20db option though. You run a pretty good chance of introducing a lot of noise and hiss into your signal.

Quote: I'm only dealing with a 15W amp here, and I'm running it at a small fraction of that, so I don't really expect it to be putting out that much power. Still, I don't think I've ever seen a motherboard which documents anything about how much it's prepared to accept along its inputs, which is unfortunate. I wonder if my roommate's Creative external can help...

It's been a while since I've done it, but at the time I was able to run the line out on the back of my combo amp (60W Tech 21 amp) into the Line In 2 jack on the front of the Creative Audigy drive bay panel. Now, doing it this way comes nowhere near the quality I get from using my external audio interface, but I still was able to use it to make a tolerable recording. I would imagine if you got the appropriate adapter, you can hook up your line out to the line in jack on the back of your soundcard with no problem.