Limiters – Cheap & Cheerful vs High-End?

[Al Krow]

Tested using a looped bass recording from a Boss RC30 Loopstation into a Markbass LM3 amp and 12” Markbass cab.

Behringer Limiter Enhancer BLE-400 - c £29 posted

 

Build, plastic housing which is expected with a budget pedal.

With all the other dials set at zero, I found that “unity” in terms of volume between by-pass and engaged had level at 4/10 and kept this level for the rest of the testing.

The BLE400 has a reputation for being a noisy pedal. I’m not sure that is fair, particularly if you’re using a decent isolated supply. The “noise” comes entirely from the application of the enhancer dial, which is effectively a brightness / treble which does add nice element of “sparkle” to the bass tone which for me is a positive when paired with a Markbass cab which tends to roll-off the higher frequencies, producing a slightly darker sound.

As the “enhance” is engaged (and even at min it’s not completely cut out) there is a small amount of tweeter hiss (which I suspect would be non-issue if your cab doesn’t have a tweeter) which increases as the enhance is increased. I found around 3 to 4 (out of 10) for the enhance provided welcome additional brightness.

Keeley Bassist - £199 posted

Compact, metal clad build, dare I say elegant. And I’ll have to ‘fess I do like how much less pedal board real estate it’s taking up compared to the Cali 76 CB I’ve just moved on! (Which, btw, I view primarily as a high end compressor and felt it was bit like driving a Porsche only on the school run to be using just for Limiter duties which in any case with peak compression ratio of 20:1 it’s not quite as geared as e.g. the Keeley for Limiter duties).

Pretty silent running on both by-pass and engaged and with Threshold set at 0 and Compression 1:1, the Gain setting at 0 pretty much gave parity between by-pass and volume and engaged volume, so very intuitive on that score; and the Gain was set at this level for the rest of the testing.

The Keeley doesn’t, however, have an “enhance” dial, so the Keeley has entirely avoided the issue of associated “enhance” tweeter hiss! So I’m not sure it’s really fair to compare them on this point i.e. I suspect that if the Behringer had no “enhancer” its noise issue would also disappear.

How did they compare as limiters?

My key objective in having a Limiter at the end of my signal chain is to be the “sentry” providing speaker protection against signal spikes from synth / filter pedals and when playing slap bass.

The recorded signal I was using from the Looper was not particularly spiky: it was just a previously recorded clip of me playing bass in a relatively measured way. I had, however, maxed out the output from the Looper to provide a decently strong / loud input signal.

The Behringer, with the Ratio set at max (∞ to 1) and Threshold at min, did a pretty good job of significantly limiting the output, however there was still noticeable volume / signal getting through. So I guess the BLE400 is “adequate” at limiting and will certainly provide some speaker protection. In other words, it’s certainly better than nothing, particularly at the price point you can get one for.

The Keeley was, however, in a different league. The Threshold setting on the Keeley ranges from +10 to -50. Setting the compression to max (∞ to 1), the Keeley managed to reduce the volume by the same amount as the Behringer with the Threshold at only -25 and then took things down to a pretty negligible volume by -50.

The take away from that for me (and I hope I have drawn the correct conclusion from this, although I’ll readily admit to still being a novice in my grasp of the technicalities of Limiters) is that the Keeley has a LOT more headroom in its ability to deal with signal spikes than the very much cheaper Behringer and this is a case in point where quality (easily) won the day.

I’m looking forward to getting my hands on a Boss LMB-3 shortly and seeing how it fares against the Keeley with the same yardsticks as I’ve tested for above. I’ll update this review once I’ve had a chance to put that through its paces and if time permits also have a play with the limiting patches on my Zoom MS-60B and Zoom B3n to see how they fare.

 

Edited August 30, 2018 by Al Krow

[Osiris]

What's the thinking behind having the threshold at minimum on the Behringer? I don't have any experience with that particular model but it's likely that with the threshold so low that the signal was not triggering the limiter to kick in, especially if your source material was fairly consistent dynamics wise. 

[Al Krow]

4 hours ago, Osiris said:

What's the thinking behind having the threshold at minimum on the Behringer? I don't have any experience with that particular model but it's likely that with the threshold so low that the signal was not triggering the limiter to kick in, especially if your source material was fairly consistent dynamics wise. 

With the Threshold at min you have the Limiter operating at "full pelt". 

If we calibrate the Behringer Threshold 0 to 10 (= min to max) then with the Threshold set between 7 to 10 it had little impact on volume output (minimal limiting). As the Threshold was reduced from 7 to 0 the volume correspondingly decreased with a substantial reduction with a Threshold set at nil. 

But the Keeley achieved the same volume reduction well before its minimum Threshold ie it had plenty of limiting capacity left in the tank, over and above what the Behringer is capable of. 

Maybe the better way of putting this is that for any given Threshold setting the Keeley is more effectively limiting (i.e. as measured by the output volume) than the Behringer when they are both set to max compression.

Edited August 25, 2018 by Al Krow

[Osiris]

8 hours ago, Al Krow said:

 

If we calibrate the Behringer Threshold 0 to 10 (= min to max) then with the Threshold set between 7 to 10 it had little impact on volume output (minimal limiting). As the Threshold was reduced from 7 to 0 the volume correspondingly decreased with a substantial reduction with a Threshold set at nil. 

 

OK, understood, thank you. It seems that the Behringer threshold control works backwards to just about every other compressor that I have ever used, seems a bit of odd design decision to me but I guess you get what you pay for 

 

 

 

 

(I was going to use the 💩 emoji but that would just be puerile).

[Al Krow]

Lol! However, in the defence of "Cheep & Cheerful" I'm not sure it is backwards?

e.g. The dials on the Behringer are exactly the same as the Boss LMB-3 on which it is based (and which I am looking forward to putting through its paces, when it arrives later this week) with Threshold going "min to max" clockwise; and the similarly on the Keeley they go from -60 to +10 (i.e. "min to max" clockwise).

Threshold dictates (as I'm sure you know) when the compression kicks in and is then applied to everything above that threshold or shelf. At "min" (or -60 in the case of the Keeley) the compression will kick in at very low input volumes  => overall the pedal is providing the maximum limiting it can.

I suspect it was more likely my lack of clarity in my review above than the Behringer being backwards that's caused the confusion here.

[Al Krow]

12 hours ago, Osiris said:

OK, understood, thank you. It seems that the Behringer threshold control works backwards to just about every other compressor that I have ever used, seems a bit of odd design decision to me but I guess you get what you pay for 

I just put the Limiter on my MS-60B through its paces, I now understand why you thought the Beheringer threshold control were backwards - it's certainly the opposite way around the Zoom which has maximum limiting when the Threshold is also set to maximum. But I'd actually suggest the Zoom is the one out kilter here!

Zoom MS-60B Limiter - "Free" effects patch

So with everything set to minimum on the Limiter - the parity volume setting to clean by-pass was 3/10 (strictly 50/150)

When set to maximum limiting i.e. with Threshold at 50/50, Ratio = 9 it managed to cut the volume, but the Keeley matched it on -20 /60 Threshold i.e. it wasn't as good as the dedicated budget Behringer - I guess that is to be expected given the maximum compression ration of 9:1.

In addition there was a bit of distortion/dirt/noise introduced into the signal at maximum compression which was unwelcome.

Putting 4 Limiter patches in series on the MS-60B made very little difference to its effectiveness as compared to a single patch.

Conclusion

Not as effective as the budget Behringer and considerably worse than the Keeley. Combine that with the inability to easily adjust the Limiter settings on the fly on the MS-60B and I certainly wouldn't want to rely on the MS-60B Limiter effects patch to be protecting my cab from signal spikes.

 

Edited August 26, 2018 by Al Krow

[Al Krow]

Boss LMB-3 - £77 posted

Got my hands on a "road worn" Boss LMB-3 today.

It's actually very similar to the Berhringer, which I guess was to be expected given that the Behringer is a LMB-3 clone.

Key findings:

1) The 'Enhancer' dial added a nice 'sparkle' to the bass tone via my Markbass combo.

2) Tweeter hiss caused by 'Enhancer' being used (but not really noticeable when you're playing). Very marginally less hiss than the Behringer

3) Neutral output was not quite 12 o'clock (it was 4.5/10 vs 4/10 on the Behringer) - no biggie either way

4) With 'Threshold' set at min (for max overall compression) this managed to cut the volume = -30 on the Keeley scale (max = -50 on the Keeley). The Behringer got to - 25, so the LMB-3 was definitely better at limiting than the BLE 400 but not really causing the Keeley to break into a sweat

Obviously you get a sturdy metal casing with the Boss vs plastic on the Behringer.

Edited August 30, 2018 by Al Krow

[Al Krow]

Summary

Well it seems to me that in terms of being an 'effective' Limiter there is a definite correlation between price and quality, so you pays your money and takes your choice:

Best Limiter - Keeley Bassist

Runner up - Boss LMB-3

Third (but not far behind the Boss) - Behringer BLE 400

Last (by some margin) - Zoom MS-60B limiter sim

Edited August 31, 2018 by Al Krow

[Al Krow]

I've managed to move on my LMB3 already and am due to post it tomorrow. Before it's gone I thought I'd get some recordings done with it in different compression and limiter settings.

1. LMB3-I in clean by-pass

 

LMB3-I.WAV

[Al Krow]

2. LMB3-II with compression and threshold at noon

 

LMB3-II.WAV

[Al Krow]

3. LMB-III with max compression, threshold still at noon

LMB3-III.WAV

[Al Krow]

4. LMB-IV with max compression, threshold at max

LMB3-IV.WAV

[Al Krow]

5. LMB-V with max compression, threshold at MIN

As you'll probably all be familiar the Threshold control sets a volume threshold BELOW which no compression occurs; so when Threshold is set on MIN everything above this min threshold is being compressed and when combined with compression at max ratio you're getting the pedal working 'hardest' to limit the signal.

You can hear that the overall output has been more compressed with this setting - this the LMB3 in it's max limiter mode.

 

LMB3-V.WAV

[Al Krow]

Just for completeness. Here's the Keeley with compression on max and threshold at -35.

I used -35 as anything lower than this was not triggering the automatic recording on my Boss RC-30 when I started the looped bass line! (The same looped signal was used throughout to ensure a very uniform input signal for comparison purposes).

Bear in mind that the Keeley has a min threshold of -60 at which point the signal is virtually inaudible. 

The Keeley is in a different league in it's ability to limit and for me more than justifies the price differential over the LMB3. It's the one that will be staying on my board.

Keeley (on -35).WAV

[garyt]

The ratio on the LMB-3 can squash your sound too much.  I have the LMB-3 permanently on, but very subtle.

level - 12 o clock

enhance - 9 o clock (any more and it's too much hiss)

ratio - 9 o clock (subtle compression only)

Threshold - 3 o clock

If a pedal doesn't sound good I won't use it, but on these setting, I honestly think there is a subtle improvement.  The enhance circuit is lethal though - it does make the bass sound good, but there's too much hiss when you're not playing and it sucks the life out of the bass when mixed with drums and guitars. 

[skidder652003]

I set my LMB-3 at everything on 12 o clock, maybe the level at 1 o clock if the guitarist and drummer get a bit cheeky on the volume, the difference with it off or on in a band mix is so subtle as to be not really necessary IMO but it does smooth out my spikes in volume but still allows me to play quietly during those moments its necessary.