[Beta] SOL-4 – Transparent Limiter with No Hidden Behavior

[Lesha]

Thanks for taking the time to compare it — really appreciate that.

That’s a very interesting observation about the kick losing its initial power at higher gain reduction. I’d like to understand that behavior a bit better.

If you don’t mind sharing, what kind of material or genre are you testing with? Also, are you mainly pushing it as a maximizer or using it more conservatively?

In some cases, the interaction between attack, release, and the transient shaping can affect how the initial hit comes through, so I’d be curious to hear more about your settings and test case.

Thanks again — this kind of feedback is really helpful.

I like to push it to be able to hear what any limiter is doing because almost every one of them sounds fine at lower thresholds. In this case there was 7 or 8 dB reduction, I can share the renders with you so you can hear what I mean.

[whassup]

Nice, hopefully you got some good input, seems like nobody wants to share their impressions with the rest of us.

As this is not an public beta but the dev seems to be using all available channels of communication I sent him only private feedback yet.
But now that you ask...
SOL-4 does certain things good.
Until now it didn't become my go to limiter, which is Barricade4 for quite some time.
SOL-4 can create certain warm density in a cool way.
I like the low and high release settings to shape sound with them.
Where it failed me until now is overall perceived loudness.
Generally I like the politeness of SOL-4.
It always wants to make things nice.
This works really well, until it starts to break.
Barricade4 is holding it better together before I stop to tolerate colorations.
It does different colorations the way I use it while SOL-4 has those "nicer maker" colorations.
Barricade is more of a swiss army knife as it is way more versatile.
BUT Barricade can't do what I get out of SOL-4.
So it seems a win win situation.
Different tools for different things.

[pekbro]

Thanks guys, I was just curious as to what others thought about it.

[SOL Studio]

@Lesha

Thanks, that’s really helpful.

Yes, it would be great if you could share the renders — that would make it much easier for me to understand exactly what you're hearing. Feel free to send them via PM.

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@whassup

Thanks a lot for sharing your thoughts — that’s a really insightful comparison.

I think you described the character of SOL-4 very accurately. It’s definitely designed to stay on the more controlled and “polite” side, which can work well in some situations, but also means it might not push as far as some other limiters before artifacts become noticeable.

Really glad to hear it can achieve a kind of density that complements your other tools — that’s exactly what I was aiming for.

Thanks again, this is extremely helpful.

[SOL Studio]

Quick update:

I’ve just pushed a new build with a few fixes and improvements:

* Fixed Auto Release behavior and transient handling
* Improved soft-clip interaction
* Added Detector Weight control
* Added a new Acoustic preset
* Refined gain range and True Peak response

I’m getting very close to a release candidate now.

Thanks again for all the great feedback!

[Lesha]

Tried the new build and there is some phase cancellation going on, the last one behaved well phase-wise.

Edit: I have just checked it with Voxengo Correlometer and higher frequencies are definitely out of phase.

I presume that it has something to do with the Side part of the signal.

[SOL Studio]

Thanks for pointing this out — really appreciate it.

I’ll check this immediately on my end, especially the high-frequency and side signal behavior.

I’ll report back as soon as I have more information.

Thanks again!

[SOL Studio]

Quick UI update:

I’ve added Mid / Side solo monitoring to make it easier to inspect how the limiter behaves in M/S.



This will be included in the next build I’m preparing.

Would love to hear if this is something you find useful.

[Lesha]

What would be a use case for changing the stereo image consistency? I cannot see a valid reason for such use in limiters.

[SOL Studio]

Good question — just to clarify, the intention is not to change the stereo image creatively.

Since SOL-4 uses M/S processing, differences in gain reduction between Mid and Side can sometimes affect the perceived stereo balance, especially on wide or decorrelated material.

The Mid/Side solo is simply there as a monitoring tool, so you can check what’s happening internally, and the S-Floor Link helps keep the behavior consistent if needed.

So it’s more about transparency and control rather than altering the stereo image itself.

[AndrewHullabaloo]

Really interested to try this one, cool concept!

[SOL Studio]

Thanks！

A trial version is now available here:
http://solstudio.online/2026/03/22/download/

VST3 for Windows (10/11)
It’s fully functional with a short periodic mute.

Would love to hear your thoughts if you give it a spin.

[pekbro]

btw: You could try to ask Ableton for a dev copy, not sure of their requirements.

[SOL Studio]

Thanks for the suggestion — I didn’t know they offered dev copies, I’ll definitely look into it.

Testing in Live would be really useful.

[pekbro]

Apparently I have a lic for live lite if you want as well. Happy to give it to you, I'm never going to use it. Not sure of the limitations on it, e.g if you can use plugins with it, probably.

It's not really worth anything heh, possibly good enough for testing purposes.