The IEM (in ear monitors) Bible thread - a guide to help every musician

[JPJ]

So these arrived in the post this morning. ACS Engage Classic custom moulded IEMs. Tried them for fit and they’re perfect. Will try them with my bass later today, but no chance to try them in anger until the new year. 

[wateroftyne]

On 16/12/2025 at 18:08, EBS_freak said:

And there goes all your bass.

 

Just curious (and to repeat what's already been asked) - do we know for sure that these are a bass-killer?

I prefer the idea of the Ambients in principle, but not if they sound like an old-timey radio.

[dave_bass5]

On the back of that question, is the effect the same (more

or less) as having a slightly loose earpiece, or is there more to it? 
i know i lose a lot of low end when one of mine gets a bit unseated. 

[Al Krow]

Interesting to pick up on this. Our singer mentioned on Sat night she only used one ear piece and left the other one out "otherwise she felt disconnected from the band and audience" - which is a classic IEM conundrum.

It doesn't affect me at all in the same way - I enjoy the clarity and comfort of having a tailored IEM mix and no one's complaining about missing out on the experience of a deafening guitar amp - ok maybe the occasional dep guitarist - now we're all going through FoH apart from the acoustic drums.

 

I don't really fancy the additional set-up faff and need to worry about an additional source of feedback from an ambient / overhead mic, just for the sake of one band member, but was wondering if there's decent ambient IEMs on a par with the KZ ZARs we're using, that don't cost the earth, and she can treat herself to a pair?

[EBS_freak]

To be clear - if the seal is broken, ambient or otherwise, there is a tradeoff in that you start to lose bass response. How much of that which is tolerable - but as a bass player, you probably won’t appreciate it.

 

Best practice is to think along the lines, anything you want to hear, you pump in via the mix.

 

There is a line of thinking that if you have a bass rig on stage, having that come in ambiently offsets the bass loss… but the goal is to keep stage volumes low so the mix the audience hears out front is better.

[EBS_freak]

1 hour ago, Al Krow said:

 

 

I don't really fancy the additional set-up faff and need to worry about an additional source of feedback from an ambient / overhead mic, just for the sake of one band member, but was wondering if there's decent ambient IEMs on a par with the KZ ZARs we're using, that don't cost the earth, and she can treat herself to a pair?

There is no additional risk of a feedback as the ambient mic won’t be going into foh. There’s no way the ambient mic will be picking up any output from the IEMs.

 

To be fair, setting up an ambient mic is pretty low effort.

Edited 20 hours ago by EBS_freak

[wateroftyne]

7 minutes ago, EBS_freak said:

To be clear - if the seal is broken, ambient or otherwise, there is a tradeoff in that you start to lose bass response. How much of that which is tolerable - but as a bass player, you probably won’t appreciate it.

 

Best practice is to think along the lines, anything you want to hear, you pump in via the mix.

 

There is a line of thinking that if you have a bass rig on stage, having that come in ambiently offsets the bass loss… but the goal is to keep stage volumes low so the mix the audience hears out front is better.

In that case I might go with the ambients - I don't think we'll be silent stage any time soon. Thank you.

[JPJ]

We’ve gone with a couple of ambient mics, with a gate side chained off my bass channel, as I am probably the only band member playing every note on every song. Only tried it once and it works well. I do need to raise the gain on the ambients a little but these coupled with the general pick up from the vocal mics works for us. 

[EBS_freak]

Why would you want to gate?

[Muzz]

I've spoken to ACS about their Ambient series, and while they do acknowledge there'll be some loss in bass response, their approach has been to design the inears to minimise this. It's a trade-off, I guess, and the results will be acceptable to some and not others. Sadly I don't have the cash to try them out, and like all custom inears it's a leap of faith. I sometimes have to pop one inear out to hear the drums properly (venue/setup depending, especially with deps), and even then (with the bass turned up in my mix), it's plenty.

 

Talking to other band members, though, I think the ACS 'squidgy' casts are more comfortable than the harder shells of some other vendors...I can wear mine for hours, where the other guys (on a long day's session) were getting uncomfortable.

 

I would add that I've done some gigs on the runup to Xmas with bands that don't have the full quiet stage/inears setup, and I absolutely wouldn't go back; not hearing myself clearly and accurately (as well as at a volume I can control) is a deal-breaker for me these days.

Edited 4 hours ago by Muzz

[JPJ]

11 hours ago, EBS_freak said:

Why would you want to gate?

To close the ambient mics when we are playing to minimise the FOH spill into our in-ears