A high quality preamp is always a good investment, but based on what you've stated so far, I don't think that is what you need. Consider this: The output of guitar pickups are designed to work and sound optimally when plugged into a guitar amp, which typically has an input impedence of 1M Ohm. Unfortunately, most computer audio interfaces, even with the designated "instrument input" have no where even NEAR that impedence. The result can be a thin, weak, lifeless direct guitar signal that also doesn't respond or "feel" like an amp at all when played.
 
Fear not, there are solutions such as Motu's ZBox (only $40), Radial dragster ($50), among others that correct this impedence mismatch between your guitar output and your computer audio interface. You may also find some preamps with a proper instrument input. I personally use a Safe Sound Audio P1 preamp for microphones into my sound card, and it also happens to have a 1M Ohm input for instruments. In addition to a fantastic onboard transparent compressor and other features, it's by far the best sounding guitar/bass "DI" I've ever encountered for recording a direct signal to use with software based amp simulators.

Hi Metz, My answer would be, you probably don't need another gain stage but it all depends.....Not a very good answer is it?
 
I agree Houndawg, impedence is a biggie not just in recording guitar but other sources as well.
 
My general rule of thumb has been that if I need to drive my sound card pre amp into an unusually high range to get decent results, and if this induces more harmonic distortion(loud hiss) into my mix, then it's probably time for a preamp. In that case the basic preamp demands another stage or a better match in order to be at optimum. Otherwise the results will be full of noise and the signal will suffer as a result.
 
If there is a problem it could be in gain staging . I would check that first. Setting the optimum gain without excessive distortion. Turning up , say, a guitar pedal all the way means that you go into the chain already pumped up too high and this affects all successive stages. The channel strip in Sonar has both a volume slider and a gain control at the top. All of these variables enter into it....guitar gain>preamp gain>software gain, which includes channel, master and sends.Gains in software tend to be cumulative to some extent. If you get the gain right on your guitar channel and add a send to it, and take that send to master, even if you don't add anything to it, you added a gain stage and you can hear the difference in overall sound with both stages running.Next thing you know the guitar is overloading the master.
 
I have heard some stunning guitar tracks recorded with stock preamps. Unfortunately none of those were mine....seriously you can get good results in many cases with stock preamps.
 
I bought a preamp not long ago..the ART MPA Pro 2. It isn't the kind of thing that anyone who is pro wants to be seen dead with, but I must say. I get good results with it. It's a step up from factory microphone preamps but a few steps below the really good stuff. I definitely notice an improvement in my sound with it. It has an impedence control,two channels,has a control for both input and output. It has tubes and they really do something more than warm the plates,comes with a 20bd boost switch,has M/S and even an increased plate voltage control....I think the largest single benefit it offers me is that it can make up impedence and also offer a gain stage so my other primary gains are are not straining and therefore the effect is a smoother more dynamic recording. Unfortunately if you bypass the XLR inputs and use 1/4" jacks, like an electric guitarist would do, then you bypass some of the controls. This is easy to get around with a few D-boxes. If I put my HD500 into it, it sounds way better than going into my stock amps. YMMV.
 
Some guitarists on this site recommend using a hardware compressor. No delay latency like you get with the software compressor, offers better control of your signal going in and an added benefit is that most hardware compressors have a gain make up stage.That gain stage could also make life easier on your stock preamps.
 
 
 
 

Li

You probably won't find a preamp that sounds better for $300.  It may sound different, but not necessarily better.  Good quality preamps usually go from $850 to $3000 for stereo. 

AT is a great source to listen to on the subject of preamps. He has helped me a lot. His mention of Warm products is spot on. Great pre's!! Another one to consider is the ISA One. Might want to check the used or bidding web sites. You can probably find your price point.

"investment" implies that you are serious about upping your game, front end wise.
 
300 bucks aint gonna get you there.
 
for another 175, this would be a good 'investment' at entry level:
http://www.fmraudio.com/rnp.html

Starise
 
 
I bought a preamp not long ago..the ART MPA Pro 2. It isn't the kind of thing that anyone who is pro wants to be seen dead with, but I must say. I get good results with it. It's a step up from factory microphone preamps but a few steps below the really good stuff. I definitely notice an improvement in my sound with it. It has an impedence control,two channels,has a control for both input and output. It has tubes and they really do something more than warm the plates,comes with a 20bd boost switch,has M/S and even an increased plate voltage control....I think the largest single benefit it offers me is that it can make up impedence and also offer a gain stage so my other primary gains are are not straining and therefore the effect is a smoother more dynamic recording. Unfortunately if you bypass the XLR inputs and use 1/4" jacks, like an electric guitarist would do, then you bypass some of the controls. This is easy to get around with a few D-boxes. If I put my HD500 into it, it sounds way better than going into my stock amps. YMMV.
 
 

A friend of mine, Mike Pachelli has a couple of the ART MPA Pros and he's replaced the stock tubes with some Telefunken tubes.  He says the MPA will fool you if you change out the tubes.

All that said, for the benefit of the OP, if he is going to run plugin amp simulators I wouldn't bother with an outboard preamp.

Mod Bod

Starise
 
 

A friend of mine, Mike Pachelli has a couple of the ART MPA Pros and he's replaced the stock tubes with some Telefunken tubes.  He says the MPA will fool you if you change out the tubes.

All that said, for the benefit of the OP, if he is going to run plugin amp simulators I wouldn't bother with an outboard preamp.

 
I still think it makes a difference Dave. The better sounding/stronger source will impact the sound a amp sim will further process. (ugggg, I sound so boring)  :) 

I am looking at tube replacements for my MPA.....thanks for the info. In my case I was actually using those tubes for some coloring and even, dare I say, grit if turned up high enough. The simm would be similar though ...boy I sound boring.