Well, please don't take offense with this, but:
I would tend to trust a decent set of phones (Sennheiser HD280, Grados, Sony 7506, etc) that will set you back approx $100.00 (USA street price) over the PA rig you have. From personal experience, I would say that the JRX100 cabs are too much "boom & sizzle" to rely on them. The end result will tend to be "boxy" because your EQ and mic placement decisions will be made by listening to a hyped top and bottom end. As for the Peavey amp, their distortion content, while being acceptable for the PA applications, will additionally color your sound and affect your mixing decisions. I say skip the PA rig (which can easily create the feedback issue, too) and learn to deal with phones (short of a "real" playack system).

thanks for your reply

I take no offense at all!!! (totally on the contrary!) I'm totally new to this stuff for the most part, and really have no clue what I'm doing other than what my ears tell me. So with the phones how would I go about playing along with my tracks? Are you saying just do everything through the phones and plug directly in to the four track system?? Also ...I had some built-in effects on the PA that I was hoping to utilize on some songs.
Should I plug the guitar through the PA and listen to what I'm doing through the phones while I play? Thanks for your response and sorry for my lengthy reply. I'm anxious to get as much solid advice as possible. -dave

sirpicksalot, you can actually produce a fairly reasonable product with your little Tascam Portastudio 424 MKIII. Especially if you run it at 3 3/4 IPS, while using the DBX noise reduction.

Forget about the PA amplifier. I second the headphone suggestion. Some of the hipest new studios, don't have a control room per se. The control room is the studio. The studio is the control room. And everybody uses headphones when tracking and doing overdubs. If you need to, get yourself one of those headphone amplifiers if you need it to kick your butt harder.

Don't even think about using the effects generator in the PA amplifier. If you need effects, get yourself a simple, inexpensive, standalone effects processor. They are out there.

Now when you are done recording, you will need to mix down. I would assume that you would mix down by plugging the output of your Tascam Portastudio, into the line input of your computer soundcard. Not the microphone input! There is much good shareware/freeware and inexpensive audio programs that will let you optimize your mix.

But your desire for a more classic sound by using this old generation of recording devices like the Tascam Portastudio really doesn't hold up. It's a phallus see? With what a computer and inexpensive software can provide you with, you might only need to use the Tascam Portastudio as your microphone preamps, to feed your computer soundcard? That would be a more productive way to go since the limitations of the Tascam Portastudio are rather substantial. You will however need a multitrack software for recording more than 2 channels, such as Mackie Traction, which will allow you to overdub up to as many channels as you need to, in comparison to just 4. Obviously, you will want/need to produce a CD and/or MP3's, so a computer is a virtual necessity.

All of this stuff is relatively easy to do and always remember, LESS IS MORE.
MS. REMY ANN DAVID

I agree definitly headphones are the best investment you can make. You need em whether you are doing analog or digital recording. PA definitley Not a good idea. As stated you are better off connecting the Portastudio to your existing computer soundcard and transfering the audio to the computer. There are some freeware programs and plug-ins you can use to edit the recording. Look up Audacity, Reaper and Kristal. There is a Sticky under the Digital Audio Recording section of this forum that has links to a lot of good free pliugins. Plenty to get started.
To check how your mixes are coming out you can try playback mixes on a few home stereos and car stereos to see how it translates over.

mastering with the headphones is possible? is it a good idea?

thanks

Thanks for the help! I have a friend who has a really good free software program that I was planning to do the mix-down with. I'm not entirely devoted to using any of the stuff that I have. It is more a monetary issue for me than anything. I'd much rather not even be dealing with tape, but it is the most inexpensive and easiest option for a novice such as myself.
Anyway...thanks again!!! It is rare to find a site where people are as eager to help out. -dave