Yeah, I tend to ignore marketing. lol! I say this as someone who used to be a professional working audio engineer and now works in tech support for a hardware and electronics manufacturer. Think of the sidechain on a rack mount compressor (because most of them have a send/return for just the sidechain) and you run it through a graphic eq. You then turn down the low frequencies and then send it back to the side chain to keep the low frequencies from triggering the compressor. Same thing except it's built in. The Empress does have a 1/8" TRS if you want to do an external sidechain.
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How important is the sidechain HPF for a bass compressor?
- Thread starter colin0154
- Start date
I'd lean towards important.
But I've only used Broughton Omnicomp which its fixed and the Walrus Mira which is set and can be turned off or on which I never turn off. An the Keeley Bassist which I think has it set but I'm not 100% sure that's factual.
But I've only used Broughton Omnicomp which its fixed and the Walrus Mira which is set and can be turned off or on which I never turn off. An the Keeley Bassist which I think has it set but I'm not 100% sure that's factual.
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To say nothing of the plentiful harmonics those low notes contain which still excite the compressor.
Now that I have the new Cali, my first with blend and side chain filter features, I gotta say I like them. A pedalboard compressor has a different job than a studio compressor. You need one setting that works all night. Those features might help you get there.
Now that I have the new Cali, my first with blend and side chain filter features, I gotta say I like them. A pedalboard compressor has a different job than a studio compressor. You need one setting that works all night. Those features might help you get there.
I'm aware of what the Empress does. This still doesn't change the fact that its compression is applied to 100% of the frequency bandwidth regardless of HPF setting, and thus the net effect on all frequencies is the same. Any claims about it freeing up the low end, or giving a bottomless feeling, or any other statements pertaining to changes in tone don't appear to have any merit. It's either compressing or it's not.
I'd say it depends on what you want to do with it. I use compression not very heavily and have noticed that I do not need a HPF in the sidechain. I used a lot of pedal compressors and the HPF was not the deciding factor on any of them. Can be nice to have when you're going low and compressing hard.
I use a 5-string and my go-to compressor live and for recording is the Big Box Cali76 without a HPF.
I tend to think that Multiband compression and the blend feature can work in a similar direction as the HPF in the sidechain.
There are a lot of options today
I use a 5-string and my go-to compressor live and for recording is the Big Box Cali76 without a HPF.
I tend to think that Multiband compression and the blend feature can work in a similar direction as the HPF in the sidechain.
There are a lot of options today
IME sending a compressor a signal with a lot of bass boost can produce results that IMHO sound unnatural (bad). I generally prefer compression before EQ for this exact reason. Using an HPF in the sidechain is just a different way of managing the problem. Putting an HPF in the sidechain reduces how sensitive the compressor is to frequencies below the knee of the HPF. Essentially less compression triggered by the lows.
It should be noted that some basses produce more lows than others. So having the ability to create a custom EQ curve in the sidechain could help you trick a compressor into giving you the type of response you want with different basses.
I'm with you 100%. I've tried explaining this to folks here till I was blue in the face and eventually just gave up.
The only reason I can think of for the low end sounding less compressed in practice with a HPF sidechain dialed in is because there's (typically) just less overall compression happening if you HPF the sidechain and all else is left the same.
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Well... I know what you're trying to say, and effectively yes, but... an HPF in the sidechain reduces the level of low frequency content in the detector signal which may trigger the compressor. A single band compressor is not any more "sensitive to lows" than it is sensitive to the entire incoming signal, regardless of what's going on in the side chain. The compressor threshold is a loudness parameter (decibels) independent of frequency (Hz). Any peak in the audio signal will trigger the the compressor based on how much the peak exceeds the threshold, by an amount set by the compressor ratio, regardless of what specific frequency the peak occurs at.
Splitting hairs at this point, I know.
For example. If you had a compressor with a sidechain input, you could feed the comp a send from the kick drum, high hat, or a metronome click, or some drunk idiot screaming into a mic whenever he pleases... whatever. The compressor threshold only "sees" the sidechain signal, but acts on the audio signal, So whatever is happening in the sidechain... that click could be 40 Hz or 10,000 Hz or anything in between.... doesn't matter. When the detector/sidechain signal exceeds the threshold, the compressor will trigger and clamp down on the audio signal.
HPF sidechain only reduces the level of the low frequency content in the detector signal, with the intent of making the true attack peak of the note more "visible"... Instead of a gigantic signal bump at 100 Hz overwhelming the detector threshold, now the comp can "see" the true peak of the note attack more precisely, allowing you more precisely dial in exactly what you want the compressor to do when the note hits.
The way @Wasnex has described is closer to multi-band compression, where you have completely separate and independent threshold and ratio parameters for different frequency ranges. In that case the lows and highs are actually compressed completely independently from one another. You're effectively splitting the signal with a crossover and sending it to two separate compressors, then recombining the compressed signals at the output.
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I have experience with compressors, a HPF as well as a side chain. . I’ve not had a compressor with a side chain HPF. So I more of a question here as opposed to a statement of fact. Is the purpose of this side chain to mitigate the exponential effect of another pedal that is sensitive to gain if that makes any sense?
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True. When i hear side-chain i automatically think it's external source side-chain. It's what i'm used to on the production/engineering/plugin side of things.
Not splitting hairs in my book. Great clarification....A single band compressor is not any more "sensitive to lows" than it is sensitive to the entire incoming signal, regardless of what's going on in the side chain. The compressor threshold is a loudness parameter (decibels) independent of frequency (Hz). Any peak in the audio signal will trigger the the compressor based on how much the peak exceeds the threshold and the setting of the compressor ratio, regardless of what specific frequency the peak occurs at.
Splitting hairs at this point, I know.
This is why I think good metering is so useful on a comp pedal for bass, especially for a five stringer - really helps visualize what's happening when you wallop on that low B string.
I know what Wasnex is trying to say and I know that he knows what he's talking about, so I am trying not to ruffle any feathers.
For us nerds, it's very important. For the rest of the world, it's not.
Applying EQ in the sidechain, definitely has an impact how sensitive a compressor is to different frequencies.
Let's a say a compressor responds equally to all frequencies and the threshold is set to 0dB. Any frequency that goes above 0dB will trigger the compressor. It does not matter what frequency exceeds the compressor threshold, compression will be applied to the full bandwidth of the signal.
This shows a 6dB per octave HPF set to 2khz.
Let's imagine this 2k HPF is inserted in the sidechain of our compressor. Now, the level in the sidechain is attenuated -3dB at 2k; so the compressor will be 3dB less sensitive at 2k. In other words now +3dB is required to trigger the compressor at 2k. However at some point above 2k, the compressor is still triggered by exactly 0dB.
At 250hz the level in the sidechain is attenuated by -18dB; so the compressor will be 18dB less sensitive at 250hz. Now +18dB is required at 250hz to trigger the compressor.
At 125hz the level in the sidechain is attenuated -24dB; so the compressor will be 24dB less sensitive at 125hz. Now +24dB is required at 125hz to key the compressor.
For all practical purpose the compressor is not going key off low frequencies, because the signal in the side chain is attenuated so far below the threshold.
That doesn't mean the low frequencies won't be compressed. Anytime the signal at the detector goes above 0dB, compression will be applied to the full bandwidth of the signal.
I've reviewed more than 100 compressors now and that has led me to believe that I personally do appreciate an adjustable side chain filter. That said, I value a wet/dry blend more. Read my reviews of both of the compressors the OP is considering here: Compressor Pedal Reviews | More than 100 compressors reviewed
I've read your reviews and it's really helpful. I do agree that wet/dry blend is more valuable than sidechain hpf, that's the reason why I'm replacing my Aguilar TLC for something that comes with a blend pot.
Both Empressor and Trickfish seems to be nice, but after reading all the replys, I think it's hard to tell which one would really fit me unless I try it myself.
The Empress will probably do what you want if you actually know what you want and and take the time to learn how to make the Empress do it.
I would guess that for most bass players that is not the case and a simpler compressor will generaly yield better results. It will compress the bass signal with less margin of variables that could take the effect further away from the desired output.
Very important to me. My. First compressor pedal, which is highly rated and liked my many bass players, always made my tone feel too squashed to me. I find it important to have a variable low pass filter and mix control (to blend compressed and uncompressed signals) to achieve my tone goals
On the Empress, the center points on all the controls are all good starting points - if you don't know what you are doing, set everything at noon, and it'll sound fine. As you learn, you have the flexibility to do things with it that a compressor with less controls won't do.
