Great information.  Generally, I'm pretty happy with what I've been able to do.  But I struggle with how long it takes - I have to export tracks and try them on a bunch of different systems before I feel comfortable with the results.  It would be nice to have some visual feedback - even just to confirm that it will be consistently acceptable across environments.  

this is why pros have incredibly expensive front ends, and monitors, in treated rooms...
and it still takes them quite a while.
 
if it was easy, everybody could do it....
and not many can.
 

Really?!?!  You don't think Har-Bal could replace the need for all that?  You sure all that isn't for show?
 
I'm pretty sure this is the secret hidden chapter in Katz' mastering book - remember how CDs from 90s alternative bands would have secret songs where you had to listen 10 minutes past the end of the last song and there would be an extra "secret" song...  If you stare at the last page of the Katz book for 10 minutes - writing appears!  It says... "Eh, screw it!  Just get Har-Bal - it's scientific!"
 
I'm still going to get it!  And dream about a studio with nice monitors and treated rooms!

 
The really expensive front ends and monitors can also be tricky. They tend to make everything sound good. I know more than one pro who does the same thing I do at the end, which goes something like this.
 
Export. listen on 4 different headphones, nice front end and monitors, ipod speaker, TV sound system, both my car and my wife's car, a small sound system in my workshop... Take notes, tweak, export, repeat. And this might take 8 or 10 iterations to get it right. The pros might not have to do as many iterations as I do, but many of them do this at least once or twice.
 
Now I export, bring it in to har-bal, tweak and export. Listen on all the same places, but only take maybe a couple of notes. Maybe go back into har-bal and tweak some really minor things. and I'm done. Check out any of the tunes in my sig, you might not like the tunes but the balance is pretty good on all of them. Every one of them has been through har-bal.
 
gabo

AllanH
Another set of plugins that I find excellent: TokyoDawnRecords (TDR)
http://www.tokyodawn.net/tokyo-dawn-labs/
 
The Kotelnikov compressor is incredible, even the free one. I suggest watching the video.
 
Allan
 
 

^^ This and Limiter №6
https://vladgsound.wordpress.com/plugins/limiter6/
and you'll be surprised at the quality of these free plugins.
I also was looking for a good maximizer/limiter plugin. Lim6 is outstanding. Yet there are other plugins and developers to consider:
Toneboosters
DDMF
But if you are not looking to spare some cash, then iZotope bundle is hard to beat.

gbowling
 The really expensive front ends and monitors can also be tricky. They tend to make everything sound good. 

If your really expensive monitoring setup makes everything sound good, it's not doing its job.  To be effective, it needs to reveal ruthlessly what the source sounds like, warts and all.  A bad recording will sound terrible through a transparent monitoring chain.  Only a great recording will sound good, letting you know that it doesn't require much further processing.  
 
Of course, it's a good idea to listen through as many different playback systems as you can.  Some will tend to accentuate areas that may need more work.  Long and tedious process, yes.  But worth the effort.
 
Funny story:  my dining room used to house my primary stereo rig, an exotic system which I'd cobbled together from mostly pre-owned high-end equipment over many years.  My friend, a well-known Texas bluesman who's now gone on to the great gig in the sky, had noticed my rig (it was hard to miss if you'd come to my house) and enjoyed listening to music through it on occasion. 
 
Once, he was producing a local band's record and came over to listen to his latest mix.  One tune had a bit of guitar feedback that I'm sure sounded good in his studio, but on my rig it sounded like a square wave that threatened to blow my speakers.  The look on his face when he heard that ... priceless!  
 
He hurried back to fix that as soon as he could.  :-)
 
Cheers,
Eddie
 

That's really funny.
 
The TDL plugins are pretty nice.  I got the EQ as well and am pretty happy with it...

Have a look at Klanghelm plugins as well as DDMF. They are of exceptional quality and very fairly priced.

wst3
The downside of growing up when I did was that most parents did their level best to dissuade their kids from a career in the music business. 

This is what happened to me! I'm a couple  years older than you. We had 4 or 5 demos and backing from some really big studios. Were on the verge of a record contract. Had a nationwide tour set up. AND our parents pitched a fit and being "good kids" we decided NOT to do it.
 
The good news is I probably avoided several trips to rehab and probably a short life!
 

mikebeam
Really?!?!  You don't think Har-Bal could replace the need for all that?  You sure all that isn't for show?
 
I'm still going to get it!  And dream about a studio with nice monitors and treated rooms!

Don't get me wrong, har-bal isn't a total fix for good mastering. There is a lot more to mastering than just EQ and loudness. However, har-bal can get the biggest part of the EQ right very quickly and you can get the loudness to whatever you want and match both for all songs on an album very effectively in a very short time.
 
A studio with nice monitors and a treated room is awesome!! Even to just enjoy the final fruits of your labor.
 
gabo