These forums are read only, please use our new forums here.

Main :: POD HD


Support forums for all POD HD products


Lets talk about the use of Compression
by Dbourget on 2011-01-28 15:51:56

Could we hear your ideas over the proper use of compression (settings, types, placement, etc). I know this will be a very helpful thread as many users really don't know the correct way to use one or what a compressor actually should be used for.

Let the discussions begin.

Dan



Re: Lets talk about the use of Compression
by Brion_Kean on 2011-01-29 00:47:51

I have had mixed results trying to recreate what I do with real tube amps, in the POD.

For instance, I stick a Keeley 4-knob near the end of the fx-loop of my friends tube amp rig, and it sounds amazing. Heck, put ONLY the Keely 4Knob into the fx loop, of pretty much ANY tube amp, get it dialed in, and it will sound amazing.

That being said, I have tried that trick with putting the HD500's "boost" comp after the amp model. Also, been messing with a 2nd boost comp, or sometimes tube comp before the amp, with a tube-driver and wah. so, wah>tube comp>tube drive>amp model>boost comp

the boost comp has more setting than the other comps, it gives you drive, treble, comp, master level, bass

Anyway, basic concept as the 1st comp (tube comp) being set for on/off with fs1, works with clean and with drive pedal (fs2). 2nd comp (boost comp) stays on, becomes the new "master amp volume" same way as putting the Keeley into the fx loop of a real tube amp does. The more you turn up the amp (volume) dial, the more the signal gets compressed with the boost comp. I set that to lower comp setting, almost all the way up on level, and then use the drive and bass/treble to balance tone and tweak volume.

That 95% for the output, becomes the master for the amp level, so if it's really low, weird squashing happens. But, set right, can be an easy way to get multiple patches with different amp models to have equivalent output volumes.



Re: Lets talk about the use of Compression
by Dbourget on 2011-01-29 07:39:19

Interesting setup Brion. I'll have to give it a try.

Thanks for thr reply!

Dan



Re: Lets talk about the use of Compression
by vcuomo on 2011-01-29 13:21:25

Brion_Kean wrote:

I have had mixed results trying to recreate what I do with real tube amps, in the POD.

For instance, I stick a Keeley 4-knob near the end of the fx-loop of my friends tube amp rig, and it sounds amazing. Heck, put ONLY the Keely 4Knob into the fx loop, of pretty much ANY tube amp, get it dialed in, and it will sound amazing.

That being said, I have tried that trick with putting the HD500's "boost" comp after the amp model. Also, been messing with a 2nd boost comp, or sometimes tube comp before the amp, with a tube-driver and wah. so, wah>tube comp>tube drive>amp model>boost comp

the boost comp has more setting than the other comps, it gives you drive, treble, comp, master level, bass

Anyway, basic concept as the 1st comp (tube comp) being set for on/off with fs1, works with clean and with drive pedal (fs2). 2nd comp (boost comp) stays on, becomes the new "master amp volume" same way as putting the Keeley into the fx loop of a real tube amp does. The more you turn up the amp (volume) dial, the more the signal gets compressed with the boost comp. I set that to lower comp setting, almost all the way up on level, and then use the drive and bass/treble to balance tone and tweak volume.

That 95% for the output, becomes the master for the amp level, so if it's really low, weird squashing happens. But, set right, can be an easy way to get multiple patches with different amp models to have equivalent output volumes.

Why would you use a compressor to set multiple patches to the same volume level?  Just use the amp's volume knob in each patch.



Re: Lets talk about the use of Compression
by Dbourget on 2011-01-29 17:26:05

Well tried your set up and its just not something for me. If it works for you then that's cool.

I was really hoping that more people would jump in with their thoughts as to what a Compressor does and what's the best way to use it as well as some settings to try out. Also what is your favorite compressor to use and why? Where do you put it in your chain?

Dan



Re: Lets talk about the use of Compression
by guitars69 on 2011-02-02 17:00:54

A common story to explain a compressor is something like:

There's this little gremlin.

His job is to listen to the music and turn down the volume when it gets too loud.

The "Threshold" is how loud the volume has to be before a red light comes on and the Gremlin grabs the volume fader and brings it down.

The "Ratio" is how much the Gremlin brings it down.  The ratio is "how many decibels out:how many decibels in".  So, a 1:1 ratio means that for every 1 db that comes in, the compressor lets 1 db out.  A ratio of 4:1 means that for every 4 db that comes in, 1 db is let out.  A ratio of 20:1 is the same, but this is considered a limiter.

The "Attack" is how long it takes the Gremlin to see the red light, get off his chair, grab the slider and pull it down.  Long attack times let the transient or peak of the audio through before lowering the volume.  This can accent the "punch" of a sound by making the transient even bigger compared to the rest of the signal.  A shorter attack time will eventually cut off the transient too-which is what a limiter would need to do.

The "Release" is how long the Gremlin keeps the fader down after the audio gets quieter than the threshold, and the red light goes off.  If the release is short, then the sound will pump more-meaning that the sound will get quieter on a peak and immediately louder again after the peak is over.  A long release time means that some of the notes after will be lowered in volume still, even though they are below the threshold.

Compressors often have a "gain" knob at the end.  Keep in mind that Compression ONLY make things quieter.  The gain knob is there to bring the sound back up in volume after you squished some of the peaks.  Since you altered the peaks to make them quieter, the average level of the peaks is closer to the level of the quieter parts.  Mountains are now hills.  Turning up the gain makes the whole track louder overall.  This makes the "sustain".  The quiet parts that faded out are now louder and it makes the note seem like it lasts longer.

That about sums up how they work.  The differences in settings and types of compressors can have a big difference on the sound.  For example, an Opto compressor (it literally uses a light bulb to trigger the compression) is slower than say a digital compressor to attack and release.  This makes vocals sound pretty sweet.  You can increase the punch of a bass or drum by using a slower attack but longer release.  You can kill a transient with a high ratio, low attack setting.

An Expander is basically the opposite.  The controls are pretty much the same but instead of making the sound quieter, it makes the sound louder past the threshold.



Re: Lets talk about the use of Compression
by JB1973 on 2011-02-02 17:07:20

thanks for that explanation!



Re: Lets talk about the use of Compression
by Xsample33 on 2011-02-02 17:20:36

Could you explain where does the "poping" sound comes from when using a compressor?

Thanks



Re: Lets talk about the use of Compression
by lopez919 on 2011-02-02 19:43:33

well i cant really beat that lengthy explanation, and good job by the way/very insightfull, but i can say this. in my analogue set up i always used a keeley two knob in the front of my chain just after my tuner. with the pod i use a tube compressor right after the amp model. sounds amazing for me in my clean les paul patch. i  think this wuld be some what similar to brions set up w/the keeley four knob which makes want to switch my analogue set up. only thing is im am lacking a lil sustain as the tube comp on the pod  which does not offer this parameter. i might use my keeley two knob to add sustain but i dnt want to over kill on the compression.

idk, sometimes i dig the punchy attack the compressors can offer and sometimes i dnt. as of now a tube comp right after my amp model in my signal chain is doing just right for me.

just fyi....im using a doubleverb,first fender sim in line, with the drive  @ five and the volume cranked. eqs can b what u wish and i dnt recall the presence. i believe my threshold is around forty and my      level is around twenty. les paul w/burstbuker pros..something like that



Re: Lets talk about the use of Compression
by wnichols on 2011-02-02 19:48:23

That is a good explanation. I just wish their was a compressor in the Pod HD that let you adjust all of those.



Re: Lets talk about the use of Compression
by lopez919 on 2011-02-02 19:54:57

i aree w/nichols

.......in regards to my last post i aslo have a reverb and delay after the comp and external od pedals for dirt



Re: Lets talk about the use of Compression
by Dbourget on 2011-02-02 20:42:16

Now that we've got some people talking compressors, what's your favorite on the 500? Also; where do you put it in your chain?

I knew this would be a good discussion. Very informative guys!

Dan



Re: Lets talk about the use of Compression
by mr_slugworth on 2011-02-03 07:27:42

I use compressor models right before the amp.  Which is my favorite depends on the situation.  Probably most often I use the Tube Comp for a tubey-feeling compressor or Blue Comp Treb to tighten up the high end, but they all have different sounds and are useful.  I think the compressors in the POD HDs are much improved over previous POD generations.

When I choose/dial in a compressor, I like to think of and set up a compressor + amp to be one and the same, so the compressor is more an extension of the amp to give it more saturation, tightness, etc. than a separate effect.  I get my amp dialed in before I add in a compressor, though, and depending on what sound I'm going for or pre-effects I'm using, I don't always use one.

Probably my best compressor trick that I use on occasion is for dual amp setups in stereo.  I use two compressors after the chain splits to parallel, one compressor before each amp, being sure to suit each compressor to its amp.



Re: Lets talk about the use of Compression
by guitars69 on 2011-02-03 11:53:10

The "poping" sound?  popping?  pooping? 

The thump or punch comes from the accented transient and the leveled out sustain of the note.  That initial transient gives it the pop and the sustain helps the note maintain its volume to "feel" loud.

****************************

I just started using a compressor pre-amp.  I know that's popular in country music.  For cleans it gives a nice sustain that is punchy sounding.  For dirty, there's already compression from the distortion and it doesn't alter the tone much in my opinion.  However, using a pre-amp compression makes things like tapping pretty easy.

Keep in mind how pre and post can potentially affect your sound:

If you send a signal to a distortion pedal for some light crunch, you might find that the peak is mostly distorted and the tail of the note "cleans up" as it gets quieter.  I use this idea with delay in particular to have a distorted initial note, then let it clean up on repeats.  If you put a compressor in front, now that peak as well as the body of the note will get distorted more because they're closer to the same volume and driving the distortion pedal for the whole note.  This might be a good or bad thing depending on what you want.

For post compression, the you'll be raising the body of the sound up probably more than the pre-compression.  This will also likely increase background noise more since the signal from the amp is already a little compressed.  You're raising the noise floor a little bit more.  I don't generally use post-compression on my distorted tones.  They're already compressed from the act of distortion/clipping and it doesn't help much.  HOWEVER, limiting can make a distorted guitar sound pretty huge like Blur's "song 2" or whatever it was called.

***************************

A neat trick is "parallel" compression.  This does wonders on drums in particular by allowing the transient of the uncompressed drums to cut through, while raising the body/tone volume of the compressed drums.  Instead of putting the compressor in serial, use a compressor like a reverb in this case.  Start with an uncompressed signal, then blend in a compressed copy to taste.  This does some cool things to clean guitars too.  You might find that the peak cuts through on the clean tone, but the body is lost to the band and you can't really tell what the rest of the note is.  You can fix this by dropping the compressor in only one side of the dual channel section and compress only half the signal.  Use the gain or mixer to blend that tone in to taste.

***************************

It's usually desired to have compression be "transparent" sounding.  Meaning it does it's job but you don't really notice it.  Despite that, I think you could have some pretty cool stuff going on if Line 6 would put in a studio compressor with threshold, attack, release, and ratio.



Re: Lets talk about the use of Compression
by Brion_Kean on 2011-02-04 07:35:52

The "tube" comp is nice, and the "boost" comp has extra controls programmed into it. I want to say at least 4 or 5 settings, instead of the 2 on the rest of the comp models? May be off on that..

I am still tweaking with patches, it is so weird, you get a tone one day, come back to it, and may not sound the same. I have time today, need to adjust more intonation / setup on my strat, and will try

another pass at some comp patches..



Re: Lets talk about the use of Compression
by Brion_Kean on 2011-02-04 07:40:26

I answer to why use a comp to match volumes, yes I know -weird idea. It's because I was maxing out my FX chain and not leaving room for a volume pedal!

I then started setting the amp model to allow the exp pedal to control volume, which I eventually clued in that you can adjust the sweep of the volume range, from say, 0 to 6 or 7, instead of all the way to 11. This discovery, plus using a volume pedal FX block, has helped. I agree, that the tone is compromised by this setup, it's weird - works incredibly well on a real amp in it's FX loop.

I am not sure where in the processing chain of things the comp is actually occuring, when it's right after the amp model.

Does that place it before the cab and mic model? Or after? If it was a real amp, would be in the FX loop, so as it returns from the Keeley into the fx return of amp, it's pre-cabinet and pre-mic. (in the real world)

No CLUE how the POD HD is setup, whether it's like a real amp, with the amps cab and mic settings going after the end of the chain, etc. Not sure...



Re: Lets talk about the use of Compression
by spaceatl on 2011-02-04 07:52:36

a very broad subject...cool topic...

There are so many things you can do with a compressor...and if you add in the use of limiting too, then there are a lot of ways to approach it...

For me, I have several flavors of Outboard compressors that I like to use.

My current favorite for guitar is the Strymon OB.1 optical compressor and I could really use two of them...I prefer having a compressor first in the chain, right after a noise gate...I leave the compressor on as I don't use it for sustain, rather I use it more like a Soft Limiter where the threshold is set high so it is just taking the peaks down a touch...The OB.1 is unique in that it also have a clean booster with an EQ voicing switch...I use that as a lead boost for clean->dirt patches...clean boosts on the front are less effective for high gain tones...I would love to have an OB.1 in the loop but I have less need for the compressor element there. What I really wish is that Line 6 would model the OB.1...ok, I am going to put that in as a feature request...

Another compressor that I really like to use on guitar is the BOSS LMB-3 Bass Limiter...It has a nice little enhancer and the extended low end response makes it great for getting really cool sounding high gain drop tuned tones...again, my use is conservative...only trying to take care of the peaks, so I use a high threshold ans it really only hits when I am really digging in...




The information above may not be current, and you should direct questions to the current forum or review the manual.