(ok then, allow me to retort.......
And allow me to respectfully re-retort

. I think we have a little Cool Hand Luke/failure to communicate thing happening here, because you're completely mis-interpreting me, my Russian spacecraft friend

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I'm not saying that mixing music is no longer fun for me, it is. If it weren't, I'd have moved on a long time ago, because life is too short and too PRECIOUS to waste it doing something you don't enjoy. Lord knows we certainly aren't in it to become millionaires, so we had better enjoy it, right?.
But, assuming your CR monitors are doing the job you bought them to do, once your ears are up to speed with them there should be no reason to *have to* check them on other playback systems. I stopped automatically checking on my home system a long time ago, because I found myself being happy with what I heard and not needing to make changes...or perhaps more accurately, any further changes would wind up chasing a phantom mix; what I had was close enough to as good as the tracking would allow it to get as to define re-mixing as a waste of time. You shake your dick at the urinal too many times and it's not getting any drier, you're just playing with yourself

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And maybe we are a bit different, but after I've spent my hour or two on a mix, I've heard that song a good 15-20 times in whole or in parts in that time. Not only does the prospect of hearing it a 21st time in a row not sound very appealing at that time, there's also the question of dealing with ear fatigue; that's - for my ears anyway - not the time to be listening to the mix either for fun or for final analysis. my brain has had enough of this hook and that bridge to last me for a while, entertainment-wise, and my ears have probably had more continuous sound pumped at them than is good for them and can use either a rest or a change in source material to the next track.
I love peperoni pizza just as much as - and probably more than - the next guy, but after the 12th 'za in a row (

), I'm not only going to be kinda tired of peperoni pizza, but it's not exactly good for my gut or my heart either.
And unless it's a Beach Boys/Queen type of super-mix - which doesn't come my way all that often

- if I'm not done in an hour or two, I'm probably chasing phantoms again; it just shouldn't take that long to finish your standard three minute mix. Not because of being in a hurry - I take pride in my work and don't rush things - but simply because it just (usually) doesn't take that long.
And as far as charging the client, I'm not going to stretch out my time just to pad my bill. If I have the mix ready in 2 hours, I'll charge for two hours, and I won't add a third hour to the bill just because I spent an hour "testing" the mix on other systems, unless that testing were necessary. Now for some unusual mixes or some styles or genres I may not be used to, perhaps some such cross-testing on my part may be called for, and if so, I'll charge for it. But again, I have a mixing monitoring system that is good enough and ears that are good enough to have made that unnecessary most of the time.
What if you do need to invest more time? And why is it a complete 'waste of time' to try 'new' or unconventional things?
If you do need to invest more time, then by all means, do it. Take as long as you need. And charge for it.
My point is that if after getting used to one's monitoring, assuming one has the ears to take advantage of that fact, checking the mix on a bunch of other systems should not be all that necessary. In fact, I'd extend that to say that being able to get one's mixes right without *having to* do such checks should be a goal to strive for. If, after a significant amount of time or practice towards that goal one is not making progress, that should be a good litmus test that maybe there's a problem somewhere that probably should be addressed, because it's obviously impeding ones ability to reach the final mix. If it's slowing it down, it's probably affecting it in other less obvious ways as well.
I opened mine with 'I respectfully disagree' with yours - but you seem to make it out to be like there's only 'one way' to do things like this or something's just 'wrong' or a complete waste of time.
I'm sorry that you misinterpreted me that way. But frankly, after some five years and eight thousand posts, I'd figure that anybody who hasn't "gotten me" yet, and doesn't realize that just because I only caveat half of my posts with a liturgy of niceitys and IMHOs and "with respect"s and so forth doesn't mean that the other half of them means I'm being an asshole, are probably a lost cause to me. You said yourself that you didn't see where there was a waste of time, so I did my best to represent that POV. Nothing more.
Relax, brother; no disrespect intended, Just because I don't couch every damn thing I say in that disclaimer doesn't make it different.

Hell, I'm sure you don't go around in life couching everything you say that way. If you're going to take such responses so personally, you may want to re-think posing the questions, because you'll give yourself a heart attack otherwise. Then you'll learn the real meaning of "life is too short"

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And I stated everything I said as fact because it IS fact. That doesn't make my opinion the only valid opinion out there, and I never said it was. But it is a valid opinion nonetheless. You stated facts to back your opinion as well, and I took no offense. We live in a world where there can sometimes (not always) be completely factual "truths" that conflict and overlap. Don't kick my ass for stating one that conflicts and overlaps yours, especially when it was meant to help illuminate a POV that you yourself said you didn't understand.
G.