Opto Compressor Shootout

[jochicago]

I got my hands on the BX_Opto and decided to do a test with a few others to hear how they handle different tracks.

I think this is a bit beyond “which one do you like” since they are all good. So more of a “what do you think of this one for drums” kinda thing.

Reference, no compressor (16 bits):
(mp3) https://instaud.io/3dgG
(wav) https://instaud.io/3eBk


1 BX_Opto (default speed)
https://instaud.io/3dgv

2 IK White 2A
https://instaud.io/3dgC

3 Studio One Fat Channel 2A
https://instaud.io/3dgD

4 McDSP Opto C2
https://instaud.io/3dgF

5 SLAX by Sonic Anomaly
https://instaud.io/3dKm


Contributed Test:
Opto 32a
https://drive.google.com/open?id=1I6gQI ... Z7Rei5MqWv


Other Tested:
Scheps Omni Opto
https://instaud.io/3eB8

This I not an LA2A, so it needs parameters. I spent a while looking at the GR behavior and tried to find a balance so that it would be compressing the audio in a similar fashion as the IK LA2A across the example. I got reasonably close and I’m satisfied I gave it the same overall spirit. Volume was matched using the same approach (LUFS average to 1/10db). Comp settings: 3.7 ratio, 10ms attack, 200ms release.

---

Notes:
I tried to set them evenly by matching about 20secs worth of average GR to 1/10 of a db using a LUFS meter. I aimed to keep the GR in the 3 – 10 db range, so we can hear them at work. The compressors are on the master. I tried to refrain from mixing the song too much, just basic eq here and there and a bit of width in the vocals. I used TrueVerb for the most gentle of reverbs just so it doesn’t sound unrealistically dry.

The BX is the only one with a speed dial, the rest "LA2A" style are 2-knob units. Keep in mind that BX is not trying to be an LA2A, so it behaves a bit differently.

The song is The Palace, multitrack provided by Lewitt

[acousticglue]

2,3,4 are best, too close to tell

[D.K Envelope]

this test makes no sense
let me tell why :

opto compressors have a feedback design so
all developer have different curves:

1. For the threshold (softknee and nose curve )
2.Ratio internal ciruit behaviour (sensitive of the gain reduction)
3. different Attack and Release curves(s-curve)
4.Internal Detector Release and the Release of the actuall compresion the last 1/3 of the Gain reduction
with smoothing curve or not
5.Adabtive behaviour for Release ,Attack,Ratio
LA2a have no standard Ratio depends on the Material

endResult=

No Plugin Developer makes the same control behavior Modeling
so all compressor sounds(from the list) different but not bad

[jochicago]

opto compressors have a feedback design so
all developer have different curves

I think we are in agreement, we just have different conclusions.

3 of those compressors are direct emulations of an LA2A, so they are using the same approach and aiming for the same character. Regardless, they do sound a bit different, as it is to be expected.

It took some work to get them to match in GR (for all the reasons mentioned), but as close as I got them should be enough to hear the difference in their character. I feel I did learn from this test.

As to their sound, I'm holding my opinion for a bit, as not to reveal the models yet

[D.K Envelope]

hi thanks for your reply
but do you know how a original la2a sounds ?
it is good to compare to a original Reference Audio

but i dont want to blame your post
so have a nice day guys

[escalona]

I spent a whole 2 minutes listening while petting the cat and I like #4 the best.

[Harry_HH]

Can't tell about these samples.

My experience and ranking for the opto compressors are:
Waves CLA-2A
BX Opto
IK T-racks Opto

IK White is not as smooth as the T-racks one, to me.
BX Opto advantage is the frequency specific comp adjustment and listening function.
Waves has done pretty good job with their implementation.

[Digivolt]

I think 1 edges it for vocals and 3 for drums

It's very hard to judge though, they're all fairly similar with very very subtle nuances

[jochicago]

but do you know how a original la2a sounds ?
it is good to compare to a original Reference Audio

I don't have a hardware unit. Would welcome anyone that wants to upload a take from the reference track.

However, since I never plan to buy a hardware unit, I'm mostly interested in how the plugins sound, since that's what I'll be using in my mixes.

[jochicago]

I spent a whole 2 minutes listening while petting the cat and I like #4 the best.

How influential would you say the cat was in this decision? For instance, if you were petting say a puppy, would that perhaps had changed your perspective?

[escalona]

I spent a whole 2 minutes listening while petting the cat and I like #4 the best.

How influential would you say the cat was in this decision? For instance, if you were petting say a puppy, would that perhaps had changed your perspective?

Wife is coming with the dog in about 45 minutes. I'll check back then!

[bmanic]

Just for fun, here is that same track with compression done by Tim Pethericks newly released Opto 32a program for Acustica Audio N4 (nebula 4). I tried to go with similar amounts of GR (3 to 10dB depending on section of song) and roughly matched volume wise by ear while listening to the main part of the song where all elements are going.

Keep in mind that I used the provided uncompressed .mp3 file as source and thus this now has been converted twice to mp3 320kbps. Still it should be quite clear how well this thing compresses and the overall tone of the program.

Personally I think this is the current king of the crop when it comes to LA2A emulations. The attention to detail is just ridiculous on this program and as far as I'm concerned it's a damn near perfect emulation of the LA2A.

Link (google drive): https://drive.google.com/open?id=1I6gQI ... Z7Rei5MqWv

[jochicago]

Thank you for uploading that. It's crazy how similar all these version are, but there are subtle differences. That Opto 32a is definitely a very nice sounding rendition.

I feel after this test that I would pretty much be happy with any of these for the same application. I was also surprised to find that the Studio One version holds its own confidently.

Overall, I do hear differences. For instance, to my ears, C1 sounds vibrant but it introduces a bit more harshness to the vocals than the other versions. The Opto 32a reminds me of the strong energy imparted by the C4, but does it in a tighter way keeping better control of the dynamics. C3 sounds more modest, sort of turns down the energy (mid-heavy), which can be useful in some applications for instance if the vocal performance was more sibilant then the others would need treatment after compression but C3 would sound more natural. C2 is clean and probably middle-of-the-road in terms of energy vs even temper.

[bmanic]

To my ear what sets the Opto32 apart from the others (and everything I've basically ever tested) is similar to what the actual hardware does compared to plugins.. it just sounds more "natural". The compression and the harmonics never feel constrained or overbearing, it just does it's thing and lets the original audio signal come through in a natural way. In short: It makes the source audio sound more "real".

That's the best explanation I can give.

It's also sort of the defining character of a LA2A compressor in general in my opinion. It's no wonder it's such a beloved compressor as it's so natural in the way it operates and is dead easy to setup to taste, rarely choking on a signal. Mind you, it's worth noting that this is specifically a trait of the LA2A. There are hardware opto compressors out there that easily choke and aren't at all easy to setup. So it's not a trait of opto compression in general.. it just happens to be the trait of the LA2A which is why it's so revered.

Another rather excellent plugin version in my opinion is the one by Native Instruments (I think it was softube who developed it though).

[sleepcircle]

of course, this no longer counts as a blind test.