Pre-N-Track Compression

When do you use it?

Hi All:

I would appreciate if you would share some of your experiences using compression (i.e., hardware) at the input prior to N-Track and when you input direct and use a plug-in compressor (for other than mix-downs and mastering). Any compression settings you use in different situations would be great,too!

I’m trying to determine if a hardware compressor would be worth the investment or just stick to using plug-ins.

Thanks in advance,


I am using an old dbx163 single channel compressor in a couple ways; I often run my bass guitar straight into it, then into the mixer in hopes of smoothing out my thumb-fingered playing. I also (currently, in fact) hook it to one of the auxes on the mixer, and let just a little signal from it back into the mix. It seems to give a little more punch to vocals and soft acoustic guitar parts. Unfortunately this is a slightly noisy unit, so I have to gate the heck out of it, but it seems worth it, particularly when I route it outside the recording chain just for tracking.

There are lots of other things you can use an outboard processor for, and the magazines are full of ads for better ones than I am using, so I would vote for getting one for your studio. I plan on getting a new one soon! But I just bought a new SM58, and have to wait… :(

'til next time!
tony w

Similarly, I also run my bass thru a wired compressor first (Tampa). I also use it as a limiter for vocals and acoustic guitar, but only for those very occasional peaks.

It’s a hotly debated topic.

The general wisdom is to use it for one of two reasons:

1) you like the sound better
2) to save a take with a fluke peak (limiting rather than compressing)

The original main reason to use outboard compression was because the medium (tape) didn’t have a very good S/N ratio. 24-bit digital has a pretty friggin’ amazing S/N ratio, so it’s really not required for that any more. The digital path tends to have as much as or more range than your mixer input channels, so if you can get the signal through the mixer you can record it and don’t need compression. (Unless you have a very pricey mike preamp, the S/N ratio of the digital path is likely to be as good as or better than your mike preamp too.)

Of course, every device has a particular sound to it, and lots of folks love the sound that certain hardware compressors give to certain kinds of tracks. No arguing with that, it’s the sound that counts.

Most of us leave at least 6 dB of headroom when recording (and more when recording a live act), and reduce the chance for clipping enough so that we don’t need an outboard limiter to save the take with a fluke peak. However, it’s nice to have a safety net for some recording gigs, such as one-time-only events where if you don’t get it, you don’t get paid (or you have cross customers or whatever).

I only use software.

My suggestion is, if you have money to spend, consider spending it on mike preamps and/or studio near-field monitors. Monitors are the first priority, because you can’t mix what you can’t hear, and for all other gear (including mikes, preamps, mixers, soundcards, and computers), there is very inexpensive gear that’s way good enough to do a very good job if you’re a decent engineer. But if you’re using your home stereo speakers or headphones to mix, you get what you paid for. If you have monitors you’re happy with (and assuming you didn’t waste them by setting them near any walls), then the next item in the studio to consider upgrading is your mike preamps, because they make a big difference in the sound you get. A good preamp turns an old SM57 into a whole new thing, practically. For starters, consider the Studio Projects VTB-1, for $100. After that, the prices go up pretty dramatically, but there are a number in the $500 range that are considered worthwhile (but none of which I have, being a hobbyist on a limited budget).

And of course, even more important than studio gear is good instruments. They don’t necessarily have to be very expensive, but they need to sound good when recorded, and you can’t make a silk purse out of a sow’s ear.

I would put outboard compressors below all these items in the purchasing priority list. The bottom line is that, when recording at 24 bits, you have enough signal to compress afterwards, so unless you want the tone of a particular hardware compressor, you don’t need hardware.

On the other hand, every now and then you can find a bargain on good compressors on ebay, and there’s no reason not to spend a few bucks for a good value, without upsetting the whole priority list. I don’t know brands / models myself, but other folks here who do know have posted links to ebay auctions that looked interesting.

Listen to Learjeff…

Before you spend money on an outboard compressor, make sure you have a good understanding of just what a compressor can do for (and against) your tracks. Plug-ins are fine to use for this learning experience, and a whale of a lot cheaper. And the points about tracking levels should be well heeded. Back in the early days of digital the need to track at high levels may have existed, but with today’s soundcard technology you really don’t need to go into n-Track super hot. In fact, you shouldn’t if for no other reason than to leave yourself some room come mix time.

I’ve heard a lot of good quality mics and preamps that won’t break the bank, but truely good compression can be an expensive undertaking in my experience. You’ll find some boxes that work o.k. for less than $500 a channel, but when compared side-by-side with real deal compressors, the cheaper ones always seem muddy and indistinct.

Thanks to all. A lot of good information to consider. It sounds like I can hold off purchasing a compressor and invest in something else such as a good set of monitors as Learjeff mentioned.

Tony, is it a 163A? I have two of those, and they are not at all noisy. As far as cheap comps go (50 USA dollars on Ebay) these are great.

Tommy, if you want a good quality full featured comp to play with and don’t want to spend much money, DBX made a table top stereo comp with full features (except it only runs unbalanced, and it is either mono or stereo, not possible to do dual mono) that was a market failure. Fortunately it is not a sonic failure - the MC-6, which goes for about 40 bucks on Ebay. It also very usefully can be used as a stomp box compressor for guitar or bass.

But don’t waste money on a behringer or the like; like clava said, they generally sound crappy.

Tom, I wish it was the 163A! I picked up my 163X half-rack unit for $35US used. It actually is nice and quiet with line-level signals, but it is not as happy with single-coil pickups straight into the hi-z input on the front panel…

'til next time

Does the 163X have an input trim?

Well, there you go: for $35 or $40 bucks, it would be nice to have an item like this in the kit just to see if you like what it does. There are a lot of folks who swear they make tracks sound better, and that they can’t reproduce it using digital gear. However, I stand by my statement that there are other items higher in priority.

But you can’t go too wrong spending a few quid like those mentioned above, when it’s good gear.

I have been opposed to using compression on the input chain, partly because I coudln’t afford a decent compressor. I have used enough cheaply-bought ‘compressors’ to know that a really, really good compressor should do nothing but reduce the dynamics of the signal, leaving it unaltered in every other respect. The people manufacturing such devices demand a fair share of dough for parting with their constructions, and rightly so.

Nowadays, I use the Emu 1820 soundcard, including the excellent software compressor plug-in (proprietary format, unfortunately) from the effects suite that comes with it. I have found a setting which suits my vocalist very well, and another which suits acoustic guitar, etc. - These settings may be recalled immediately whenever they are required, and now I leave the plug-in on the microphone channel at all times.

It’s actually a nice-to-have (as opposed to need-to-have) feature, because I found out I really learned a lot about mic placement, level adjustment, peak monitoring, and how something actually sounds by not having access to a compressor. If you know your (hardware) compressor inside out, i.e. you are able to set it up for a specific setting at a moment’s notice, it may save you a lot of time when tracking, and even more when mixing. (Hint: ALTO makes a preset compressor with a vast number of presets, but without the capability to store your own) dBx makes a good, affordable range of decent stereo compressors, too. So does Behringer, if you are on a budget. (psst! save up for the dBx instead…) Remember that a properly set up compressor is not heard at all, only the way it affects the dynamic range of the material put through it.

regards, Nils


Does the 163X have an input trim?

No, but it does have an output level control.

so simple the 163X…like the best of the classic equipment it has very few controls. The only drawback to it is that if a new user of compression wants to learn about how parameters such as attack and release and ratio affect the sound entering the box, the 163x won’t help 'em learn much since those parameters are hardwired.

A joy to use on bass and kick drum though, especially for parallel compression work. They could well be noisy when using the Hi-Z input as they are unballanced (and a single coil could be worse in this regard too…). Still, it couldn’t hurt to open up a noisy one and make sure the 1/4" jack on the front is at least clean and not worn out. Any 163x in use these days has probably seen a lot of miles, and while the rear jacks may be in fine shape due to few unpluggings, the front one could be toast…

Hmm. I seem to remember that the 163A has an input trim for the 1/4 inch input. I was sort of wondering if that might be part of the noise prolem.

It looks like clavastudio answered for me - and I am okay with that! :cool:

Like I said, it is plenty quiet on the line side - and I will look into the front jack, and see if it needs a little loving care. It is a great unit even so, and I have yet to regret that $35US! It is much less noisy with humbuckers, but my budget won’t support another bass right now… :(

'til next;

Wynot, for single-coil pups where buzz is a problem, I strongly recommend NOT using outboard compression (though limiting is OK), because you can easily de-buzz the track using a wave editor. But if it’s outboard-compressed, the buzz level jumps around so noise filtering software doesn’t work as well.

Jeff, I just got one of the little Behri bass amps (Bx108), and do not think the dbx will be coming out of the soundcraft mixer’s aux loop, where it is as quiet as can be, anytime soon. I tried every small bass amp at 4 different shops, Peaveys and Fenders and Johnsons and Crates and so on, and the little Behri just had this sweet, round sound with my Ibanez bass… So the dbx gets a new job! And I do any compression I think needful in the computer. No static at allllllll… :cool:

'til later;

Well, if you can record SC pups and not get any buzz, I want to know how you do it! Th world’s best preamp would not eliminate the buzz that the pickups put in the signal.


Jeff, one way is to move to Great Britain - no 60cycle electricity there! Another way is to use and entirely battery-powered/direct current signal chain, if such a thing is possible… :p

'til next time;

ACtually, I was considering an outboard compressor/limiter on vocals just because most of the singers I have come into the studio sing softly on the verses and too loud on the choruses. Sometimes I end up doing two takes, one for the verses and one for the choruses.

I suppose I should try not to record so hot anymore. The last studio I was in was with an 8 track analog machine and I was always concerned about recording as hot as I could, but I guess with digital, I don’t need to do that anymore.