Using Sonar X3 along with a Scarlett 6i6 audio interface. I'm starting to record vocals on a project using a condenser mic that's pretty sensitive, so I keep the input gain fairly low to avoid clipping. I have a set of headphones connected to the interface as my "monitor." The problem is, I can't get a mix that's loud enough for my preference. I'm recording on the "zero latency" setting with the 6i6, and I want to be able to hear the vocal in the headphones at a much higher volume than I'm able to generate now.
 
In doing a little googling, it seems that a "headphone amplifier" might be what I'm looking for. Does that sound like I'm on the right track, and if so, anyone have any recommendations for a good mid-range unit?
 
Thanks!

Are you sure you've exhausted the options with your Scarlett's software? If your input gain is loud enough (but without clipping naturally) then you should be able to get enough gain at the headphone output, although I have no experience of Scarletts.

Having said that, I have an RME Babyface and I've heard people complain that the headphone outputs are too quiet. Can't understand it myself, because I find that I get to the level past which I would consider the level damaging to my hearing quite easily. I could never understand why anyone would want it louder. Pete Townsend ruined his hearing by listening to headphone mixes too loud in the studio.

Thanks. Yeah, I think I have exhausted the stock options on the Scarlett. I'm not looking to blast my eardrums into oblivion, but just want to be able to feel in total control of the vocal without having to strain. Don't seem to be able to get to that point with this setup. I can probably fool with the gain input a little more, but I sing fairly hard at times, and I've noticed clipping artifacts unless I set it fairly low as well as incorporating pads on both the mic and the Scarlett. I'd rather keep the input lower and then boost it after the fact to avoid that. The tradeoff seems to be a mix level lower than I'm personally comfortable with. I'm really looking for a way to boost that monitor mix level.

Some headphones benefit greatly from a headphone amplifier. It depends on their sensitivity and impedance, both of which vary greatly from model to model. Headphone amps like the ones built in to your interface are typically low-powered and relatively high impedance, and may be inadequate for certain headphones. 
 
Beware the hype around headphone amplifiers, though. Audiophiles make a big deal about expensive headphone amps but there's no need to spend hundreds of dollars on one. Not for monitoring, anyhow. You just need to make sure it's powerful enough. Buy locally or order from somebody like Sweetwater that has a no-hassle return policy.
 
The one I use was quite inexpensive and does a great job, but I can't recommend it because it's no longer manufactured. However, there is a unit from ART that's similar and also inexpensive. It's also a two-channel mixer, so you can have volume controls for both the cue mix and your microphone right at hand. If it's like the one I have, it'll be PLENTY loud. I have mine mounted on a short boom attached to the microphone stand, very convenient when you're both artist and engineer. 

That looks like it's exactly what I'm looking for, bitflipper, thanks! Just ordered it.

Another cost effective solution is the *gasp* Behringer 4/8 port headphone pre-amps. You can find them used pretty easily on the ebay or local listings. 2 other Cakewalkers and I have been using it for years now at our rehearsal space. They have dual inputs too so you can send 2 different mixes for the performer to blend. I've used a variety of cans with them and they all get plenty (too) loud.

Although the MixControl options are pretty thorough what I do when recording to get a good balance is use busses within Sonar to adjust things as I track. I set the Scarlett input trim (or now my mixer via the line ins on the Scarlett) so that the track within Sonar is getting a good signal and then adjust things as needed in Sonar's bus section.
 
So basically every instrument gets a bus (drums, bass guitar, vocals, any synths all have a bus). I group all the related tracks to their own bus, (all drums to a bus, all rhythm guits to a bus, etc...). The track levels are set so their busses are all getting a decent mix/level.
 
I also create a Pre-Master bus that everything gets routed to before the master and then that premaster gets routed to the master (I do this for various reasons but I won't get into that but one factor pertains to this).
 
So... if I am tracking and need to hear the input of the track being recorded or any other instrument I just turn up/turn down the relevant buss. If I do not want to mess with the mix of the already tracked busses what I can do is send the input of the new track being recorded straight to the Master buss and simply adjust the Pre-Master buss level to where it needs to be in relation to the new track being recorded (it is very easy to just put that Pre-Master bus level back to where it was as opposed to readjusting all the other busses).
 
Once a decent mix between the Pre-Master buss and the new track is set then I can crank up the headphone level knob on the interface as needed.
 
You have to remember that once you have your input trim set on the hardware THAT is the level being recorded no matter what level the track or buss faders are in Sonar (you can have the track muted and it will still record if you have it armed... I did this yesterday to test it actually).
 
So yeah... a headphone amplifier is a handy device to have but your 6i6 actually has TWO of them from what I just read. It is one of the most useful features on the Scarlett series. When I bought my 18i6 I was freaking out before I got it because I thought I would have to buy a separate headphone/monitor controller. When it showed up I saw I had individual knobs for both the mains and the headphone jack. SWEET!!!
 
Anyway... you will likely find uses for your new headphone thingie (they are extremely useful) but there is more than one way to skin the proverbial feline... especially when you are using a Focusrite product with Sonar.
 
Cheers.
 

And I may have completley missed the point by ignoring the "zero latency" aspect of your post (I have never needed to use that feature because even with stacks of tracks, synths and effects everything runs fine on my machine with X3 and mostly worked fine with X1 and 2). If you have serious system problems that are preventing you from recording at lower latencies that are forcing you to resort to the Zero Latency option here are some suggestions that will allow you to use the method(s) I described above by freeing up system resources.
 
1) "Freeze" your synths and effects (this is the "snowflake: button on each track and will temporarily bounce all synths and effects to audio. You  can easily reverse the "Freeze" by clicking the button again gaining access to the effects and synths.)
 
2) "Archive" any unnecessary tracks (this is the A button on each track). It will remove all the tracks from what Sonar/your system is processing and again is easily reversible by clicking the A button again. Examples of tracks to archive are any muted "scratch" tracks or leads or anything that isn't needed for you to do your new track (like maybe you just need to hear the drums and guitar to do your vocals... you could archive all the other tracks temporarily until you are ready to mix). Also a good practice is once you have tracked a part and comped the version you want to use clone the track then "flatten" it or bounce it in the second track then delete all the other clips/take lanes. That way that track is only playing and processing ONE clip instead of multiple clips. Then you archive the original track (the one that has all the original takes) which keeps them from using system resources (even if a clip is muted Sonar will still "see" them and get ready to play them if you unmute them or whatever so archiving is like deleting them without actually losing the work).
 
In drastic situations you can do a stereo mix down of your project as is into a new track then archive all other tracks so that way the ONLY track, aside from the one you are recording into, is that one stereo track which is obviously a LOT less resource intensive than even a simple 8 track project.
 
You may know all that but whatevs... I'm trying to distract myself from some other things that are making me hyper and typing up things like this is calming.
 
lol
 

Beepster
And I may have completley missed the point by ignoring the "zero latency" aspect of your post (I have never needed to use that feature because even with stacks of tracks, synths and effects everything runs fine on my machine with X3 and mostly worked fine with X1 and 2). If you have serious system problems that are preventing you from recording at lower latencies that are forcing you to resort to the Zero Latency option here are some suggestions that will allow you to use the method(s) I described above by freeing up system resources.
 
1) "Freeze" your synths and effects (this is the "snowflake: button on each track and will temporarily bounce all synths and effects to audio. You  can easily reverse the "Freeze" by clicking the button again gaining access to the effects and synths.)
 
2) "Archive" any unnecessary tracks (this is the A button on each track). It will remove all the tracks from what Sonar/your system is processing and again is easily reversible by clicking the A button again. Examples of tracks to archive are any muted "scratch" tracks or leads or anything that isn't needed for you to do your new track (like maybe you just need to hear the drums and guitar to do your vocals... you could archive all the other tracks temporarily until you are ready to mix). Also a good practice is once you have tracked a part and comped the version you want to use clone the track then "flatten" it or bounce it in the second track then delete all the other clips/take lanes. That way that track is only playing and processing ONE clip instead of multiple clips. Then you archive the original track (the one that has all the original takes) which keeps them from using system resources (even if a clip is muted Sonar will still "see" them and get ready to play them if you unmute them or whatever so archiving is like deleting them without actually losing the work).
 
In drastic situations you can do a stereo mix down of your project as is into a new track then archive all other tracks so that way the ONLY track, aside from the one you are recording into, is that one stereo track which is obviously a LOT less resource intensive than even a simple 8 track project.
 
You may know all that but whatevs... I'm trying to distract myself from some other things that are making me hyper and typing up things like this is calming.
 
lol
 

 
That is all great info, Beepster, thank you for taking the time!!

Cool, mang. Honestly my brain is on fire with annoying bureaucratic bullpizzle at the moment so it was cathartic unleashing all that. I'm just glad you found it helpful.
 
Cheers. ;-)