I only mix and master my own tunes and the tunes of some clos friends.

It might be good idea to ask for a reference mix/master they really like. Talk about the loudness wars and what they expect about that.

Encourage them to be honest about your mixes and masterings, you can and will learn from them.

What should you pay attention to when mixing for other producers?

It's their song and their vision so don't try and make it yours.  Hopefully they have come to you because they feel you can add something to the process and you're working together as a team.  Difficulties I've experienced are usually solely down to communication problems.  For example, artist might say one thing when they actually mean something else so it can take a little bit of time to ensure you're both on the same page.

Hi Volant!

I recorded, mixed and mastered a friends rock band. Before this I only had some experience with electronic music, but I'd say this was extremely beneficial to my mixing skills in general. For me the difficulties were to figure out how the guitar and bass should sound like since there are so many options and ways to shape the sound. I used reference music from the Red Hot Chili Peppers, and with that and always being in touch with the band (sending mixes forth and back) we got to a result that the band and I satisfied with. (Sure, you can never do an audiophile drum recording with 2 cheap overhead mics and a handheld recorder as kick drum mic, but hey it was a challenge and I learned a lot).

The most difficult part is probably to figure out the small path between what the band wants and what you think sounds good/right. I'd say reference bands/tracks are really helpful here, so you know where to go with the style.

Take care,
Artless Venture ♢

See when its for friends they will be honest,but when you're paying for master,the guy mastering it is usually never honest..He just wants his money. Thats what I've found..

i don't think that's true at all. a good engineer is transparent. in cases where the client only wants a master, i often provide a hand full of mixdown critique before having them send it over and if they don't get it up to scratch i tell them to hold off on it or go for the full mixdown/master to ensure a quality product. in my experience with good engineers (andy tau, mark sherry for example), they've always done the same and have been extremely helpful in the process.

from a business standpoint, any engineer who doesn't operate in this manner is shooting themselves in the foot. my workload is almost entirely based on word of mouth references and revisiting customers. and any engineer who makes it clear that he just wants his money without actually helping you is unlikely to sustain any kind of continued business

i mix a friend of mine's music a lot, which basically is just an instrumental and a bunch of vocals overlaid on it. as long as the vocals have been recorded properly, its a lot of fun. only takes a couple of hours for me to mix/master the whole thing, including some artistic freedom.

I have mixed and mastered peoples tunes yes!
 I'm actually going to start a little service where I offer to mix and masters peoples tracks but focus on trying to push getting mixes done and work with the artist to get mixes done before mastering because I'm sure as we know mixing is far more important than mastering but as stated above....some mastering engineers since it is a competitive and not necessarily lucrative field they just master the tracks and get the money! And no matter how good someone is at mastering, if the mixdown is shit, then the master is also going to be shit....just louder. Like a loud Shit.

There are many issues when working for other....first off ....mixing is (technically) subjective. How people hear and what people want to be prominent in a mix differs from each individual and each genre of music. Its hard to retain dynamics yet obtain that level of loudness for commercial release.......and this differs dependent on style. For example: some deeper progressive house focuses on dynamics, depth & soundscapes to try capture that atmosphere but something like dubstep is just slammed up against your limiter, squashed to shit and a big wall of sound....but that may be the sound a client is looking for so it is important to discuss this with the people whos music you are working on. Try to gain a sense of what they want but add your own interpretation.
 
Another issue is what you actually get given to work with. For example I prefer working with stems, since you don't want to drastically alter the artists creative intentions, ie....changing the reverbs on leads, altering how buildups or drops occur etc, however; sometimes with stems it poses limitations to the mixing / mastering. Here is one example: You could be supplied with a 'drum stem' where all the drum sounds are exported together in one WAV audio file....now you as a mixer may feel that the kick and snare relationship isn't sitting to well, simply in volumes, so it becomes a bit of a pain in the arse to alter simple stuff. Another example is if they have exported a 'BASS STEM' which houses a couple of bass sounds but their levels are way off, ie...subs way to loud in the mix......bit of a pain. I suppose the point here is to offer a service where you mixdown more stems. Tell them exactly what you want, eg: 'kick stem', 'snare stem', 'hats and percs stem', 'sub bass stem', 'main bass stem' etc.  The more things are separated from the beginning then the easier it is to approach.

A lot of people want you to mix direct from their project. If you have all the relevant plugins then it is great, however; 95% of the time....you both do not share the same versions of the DAW's or the same plugins so it just doesn't work.

Honestly, more often than not, producers have simply got their volumes of each track way off.......I tend to find people leave really sharp high frequencies in there or pump the bass way to loud to the kick....yunno simple things. Steve Duda once told a class something like 'I bet I can do a better mixdown than most people simply by adjusting volumes and not even processing stuff' .......I paraphrased there of course, but it was something along those lines. Steve wasn't being an arsehole he was merely pointing out that 90% of a mixdown is simply balancing volumes of your tracks and making space for each elemet. You gotta compensate the space and decide what elements belong in the foreground and what elements belong in the background. An artist doesn't create a one dimensional picture....the background is just as important as the foreground. The less things are fighting for space, the cleaner the mix is. Take current 'deep house'.....super clean mixdowns because there are so few elements.....drums and bass in foreground, some lead / piano / pad sat back a little....done!

so pay attention to volumes and what important elements belong to the front, which elements belong in the back, keep an eye on headroom for mastering, pay attention to phase,......even go as far as suggesting things that really aren't working in the track (although people do get shitty sometimes if you try offer constructive advice). As I said before don't try make them change their art but....gently suggest minor changes they could make to enhance the track.

when working on things for other people, the major issue is the complaints you get: ' I want it to sound like this', 'I want that', 'so n sos track hits at this rms and this doesnt' blah blah blah .....unfortunately some people just don't know what they want.....that's when you get mixing engineers or mastering engineers who stop giving a fuck and just do whatever haha!! Unfortuantlely the actual 'sound' of current popular dance music is actually a big fuck you to mixing engineers. Gotta try find that happy medium for most people.

I have done a few mixes for a friend, unpaid, and I've learned that when you aren't paid that you tend to care less, or if it's a passion work than you care more. I've gone as far as replace entire drum sounds, add parts in, delete parts, etc.  However, you don't always have that liberty, and replacing/adding sounds can take way longer than if you just mix what's pre-existing.  If I'm putting my name on it than I tend to care a lot more. If it's a work for hire, and you don't get any credits on it, I'll work with what you have.  I will say that's it's awfully annoying to have stems where every drum is in mono down the center or synths have ugly reverbs that cannot be removed without creating artifacts.  In these situations it helps to know all your tools very well, but it will only ever be but so good.