Equalization for my set up

You can get a digital EQ like the Behringer DEQ2496. Go optical from your Apple TV to the EQ. And then go optical from the EQ to your Peachtree.

I'm not sure that will fix your problem, though. If you tried the EQ in itunes and it didn't give you the bass you need, I don't think an EQ will fix your problem. I know the resolution is less with itunes, but for bass, it should have worked. Looking at your system, I think you are under powered. Your amp is probably having a difficult time driving the low frequencies. One thing you can try, if you have the room, is to move your speakers closer to the back wall. If you need just a little more bass, there's a good chance moving your speakers will work.

EQ in this situation is at best a band aid. I doubt you will be impressed. I suggest upgrading your speakers or adding a small sub.

Shakey

I'm with the guys. Adding a sub is the most logical thing to
do. Sometimes EQ doesn't fix certain issues.

Thanks for your input guys. Just to clarify. I love the clarity of my set up and on many tracks, especially newer recordings there is plenty of bass as is. I'm not a fan of iTunes because the files are so compressed. And when I've tried the EQ on it it just makes the files sound over all less clear.
I'm just looking to add a few DB from time to time depending on the track. Like adding a pinch of salt :).

A few DB where: Bass, Midrange, Treble.

Sorry, I didn't notice you were talking about only 30-40 Hz. I was going to say check out a variable loudness control (see: http://alumlabs.weebly.com/). Much simpler to operate than a parmetric EQ. But a variable loudness control will increase the treble along with the bass, which might not be a good thing for you.

"08-23-14: Ronwave
Thanks for your input guys. Just to clarify. I love the clarity of my set up and on many tracks, especially newer recordings there is plenty of bass as is. I'm not a fan of iTunes because the files are so compressed. And when I've tried the EQ on it it just makes the files sound over all less clear.
I'm just looking to add a few DB from time to time depending on the track. Like adding a pinch of salt :)."

Something's not right. If you just use a small amount of EQ in iTunes, you shouldn't loose clarity. I haven't used iTunes in a while, but most EQ's in music player software have an overall gain control, as well as the individual eq frequencies. For best sound when using a PC, you are supposed to have your volume on the player software and your OS set to maximum. But not the one on the EQ. That should stay neutral or 0 gain. Its usually half way up on the slider. With too much gain, you may start to break up kind of like when have too much gain on a phono cart.

Aside from that, try ripping some of the problem albums to wav and see how it sounds. iTunes will play wav.

If that doesn't work, try a different music player. You don't list your OS, so here's a list of free players that work with Windows, Mac and Linux. Amarok, Clementine, Audacious, Banshee and Quod Libet.

If you try the stuff I mention above, there's a good chance you'll be able to fix your problem without having to buy anything.