Guitar feedback plugin?

Hi all…
Am loving ardour 6… I am mostly a guitar player and spend a lot of my time setting up different simulated amps and effects, but the one that I cant seem to get is feedback. Guitar feedback is a chaotic effect, full of harmonics and unstable sounds. Used to be able to acheive this easily back in my Marshal amp days, but no matter what I try, I cant get anything like it digitally.

Have looked at a few effects that can now achieve it, but they seem to be very expensive vst plugins, so my obvious question is, are there any Linux plugins that can do this? Free and open source of course being the preference, but the lack of this effect is now starting to feel like a hole in my toolbox so happy to look at anything that will get me there…

I don’t think it’s a matter of digital vs analog but more bedroom monitoring level vs 100 Watts turned up to 11.
Crank the volume on your monitors as much as possible and possibly use an EQ on the output to find the spot where your guitar pickups feed back the most.

Hey Peder…
Am looking for a way to not use speakers… The VST plugins I looked at (bluecat etc) were just plugins, no amps or speakers needed. Bluecat is one of the cheaper ones and there are some very expensive studio vst plugins out there, I am just trying to see if any lv2 or other Linux plugins are around to let me acheive the same thing without a 2nd mortgage or using wine…

You could try SO-666. It’s a feedback drone synth without inputs to create digital feedback sounds. I’ve used it in the past:
Feedback drone kicks in after 15 seconds and then again at 2:45.

And maybe something like the gx_susta.lv2 plugin from the Guitarix project fed through an insane distortion would work, I think I tried with Barry’s Satan Maximizer or a Chebyshev distortion in the past.


Hi Jeremy

Thanks for the tips, will try those out this afternoon and let you know how I get on…

Now that’s a tune I have not heard in 11 years. I do recall a performance at LAC in Maynooth, back then with actual analog feedback :wink:

Yes, except if you have a very long latency, but even then you can get the strings to resonate with a feedback.

But essentially your speaker needs to provide a sufficiently high sound pressure to move air to move the string on your guitar. You can try to add some drive (more high frequency content increases the chance that some overtone will match).

If you cannot play loud, you can probably fake it with pinch harmonics.

In some case you could also try a headphone.

Hey there. I am primarily a guitarist, acoustic, electric, and synthesizer.

I don’t mean to sound pedantic, but this is a really deep subject around which a great number of unfounded myths have grown in the guitar world. To start with the kind of musically useful feedback pioneered by Hendrix and scores of others is often mistakenly thought of as a product of sustain when the reality it is a product of sympathetic resonance between the guitar strings, body, and the speakers more than the amp used.

It also depends on the frequency and proximity between the guitar and speaker cabinet, but also the characteristics of the room or hall one is playing in. Also, powered speakers are intentionally designed to be colourless, contributing nothing to the sound being modelled.

Devices like the Sustainiac approximate this by causing a pickup to behave similarly to a speaker driver built into the body of the guitar only using electromagnetic output from one of your other pickups, with some models adding refined frequency voicing. I suggest that is going to be closer to what you want than a plugin can provide for achieving authentic-sounding feedback without a speaker cabinet.

Although the title is “6 Tips For Better Sustain” @ timestamp 18:00 minutes into the video they do a deep dive into the practical and scientific facts about feedback and should serve as a useful guide in designing your guitar sound.

Thanks for the input guys, but I really do not want this being steered towards analogue feedback, can already do that and have been for 45 years… Am after a digital effect only and although I understand that it is unlikely to be the same, or even as good as an analogue effect, I would still like to know what is out there.

As I have already mentioned it, here is bluecat acoufiend…

Screaming Guitars with Blue Cat's AcouFiend, the feedback simulator - YouTube

Maybe you can still be convinced to use an EBow - Wikipedia :slight_smile:

Mess around with Rakarrack. There’s 180 presets and I can’t remember which one produces this, but it may be in the direction of what you’re after. Check the intro to this.

Hey Robin, I still have an e-bow somewhere, havent used it in years… Cool effect but it does restrict playing a lot so that would be out except in specific moments, also is not a plugin which is what I am looking for…

Hey nSpud3, not sure that feedback is all Rakarrack (have used it a lot) but maaaan that emu is cool, worth it for just that, and would love to know what the story is behind their name - ‘Go Back Wrong Wayne’…

Having a bit of a moment with my Ubuntu Studio at the moment, upgraded to 22.04, then while in that mood I dived into trying to get pipewire to work, it did not as could not install something called wireplumber so Ardour could not see my soundcard anymore. Have reverted back to pulse audio and now its all a bit unstable…

Means it may be a day or 2 before I can use it again…

A couple of things.

The software you refer to is the virtualization of analogue feedback and still obeys the same principles discussed in the video I shared trying to help you the way people once helped me.

The same features are found in wavetable software synths I use like Matt Tytel’s Vital and Arturia’s Pigments.

Second, I am 65 years old and started playing the guitar at age 9 and started playing with adult professionals at age 11. My first public performance was a DNC fundraiser for Andrew Young and Julian Bond. It was terrifying.

I hung out at the Ludlow Garage where the owner Jim Tarbell befriended me and became an important mentor in the music business.

When I could not stomach the corruption, racism and sexism that was everywhere in the rock business, he and other old-timers in the business helped me make the tough call to walk away and put my family first.

The picture below is what I was doing over 45 years ago. That is me with a heavily modified Black 1970 Les Paul Custom behind the late, great James “Pigmeat” Jarrett on piano at another club Jim Tarbell owned named Arnold’s, the oldest continuously operating bar in Ohio.


Hi Muiren…

Interesting trip through the past, nice pic and very nice guitar…
Unfortunately, the plugins you suggest are proprietory and paid for, a direction I abandoned some time ago… But thank you for the input…

The problem I see with that plugin video is that the effect is always on. Feedback is traditionally a performance technique, you bring it in and out to enhance a specific short period of time. That plugin is the virtual equivalent of standing facing your Marshall stack while you play the entire time.

Is that what you are looking for, or do you want something you can control while playing, or something you can control in post-production by using screen+mouse or control surface controls?

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I map software synth and effects controls to MIDI switches on my guitar and on the floor, as well as to my Mission expression pedals. That lets me punch in and out on specific notes as well as allow nuanced control of the effect parameters.

There is no reason why the same thing would not be true with Blue Cat’s AcouFiend and would really speed up production time to dial in feedback even when you did have the option of creating feedback using old school techniques with guitar, pedals.

AcouFiend has a huge range of settings so it wouldn’t be very practical to have all settings assigned to a switch or pedal. In a live setting, the major advantage to me (and I suspect other people) would be feedback controllability under a wide range of conditions.

This would matter a lot when I have to go directly into the board of the house PA, and worse, I have next to no control over what the engineer doing.

Blue Cat Audio software isn’t FOSS (Free Open Source Software), so what is your real point? I and my cooperative socially and financially support artists, artisans, software, and hardware developers across a spectrum of proprietary and open source, neither of which is an orthodox religion one is either part of or excommunicated.

Also, your choice of words is odd considering that you were the one who started the trip down memory lane, and I only offered proof of my own considerable professional history.

Finally, I am not being the least critical of AcouFiend but did make clear its effective use inarguably still requires the same knowledge in making use of the Larsen Effect (acoustic feedback loop). In fact because it makes possible a greater range of control it can be argued that it requires greater expertise to full exploit the software’s full potential.

Since you keep looking for unfounded justification to dismiss my help, I am happy to accommodate you and will remember not to bother in the future.

Moving on.

As in my original post, I am only offering bluecat up as an example of a plugin that does feedback, and as mentioned, it is not foss or linux which rules it out like several others that are also proprietary and not linux.
Am just trying to find something out there that I can use with Ardour, a post production plugin that will enable me to play with guitar feedback…
I appreciate the input from everyone but I am having to repeat my original question so that I can steer the conversations back to my original post.
Suspect I have not been clear enough, am looking for an open source plugin that will simulate feedback, not paid for, not using amps, speakers or headphones on my pickups, just a plugin that will work in Ardour, like Bluecat, which is just an example of a plugin that does what I need.

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Despite what I said, I continued trying to help by searching without success for a Free Libre Open-Source simulation plugin for creating the Larsen or Acoustic Feedback Effect that functions like the proprietary AcouFiend plugin by Blue Cat Audio.

I believe there you are likely not alone and that Blue Cat Audio’s offering may actually help to encourage support for the creation of a free open source “feedback” plugin.

I would be open to discussing the addition of developing this effect plugin as a near term project for Síofгa Tech, an ArtScience Worker Cooperative for Music Instruments and Performing Arts Technology (Hardware, Software, Services) that I work at founding.
More about Síofгa Tech here and The ArtScience Manifesto, authored by Robert Root-Bernstein, Todd Siler, Adam Brown, Kenneth Snelson here

One of the things I have always thought odd was how people can be so passionate about Free Open Source Software but rarely organise formally as cooperatives. Do you understand and support cooperative labour, economic democracy for social democracy?

Do you see how the ethics of cooperatives align with the ethics of Free Open Source Software, Hardware, and Service Communities?

And are you are willing to donate your time and talent to help organize talent and support for the plugin you and no doubt others want?

I am a member of CoTech a network of ethical co-operatives providing technology, digital, and creative services. Though diversity doesn’t seem a high priority in the community, the principles and practices of CoTech in all other regards are admirable. Link to their manifesto and a link to their forum.

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Are you wanting to use this in combination with Guitarix and managed using Ardour and your hardware audio interface? What processor are you running on ARM, Intel, or AMD?
FYI, I created a post about your search on the Guitarix Reddit here but it is being held for review by the Mods I assume.

Is this something that could be implemented with other plugins? Take the signal from guitarix to a delay adjustable from about 0.5ms to 2ms, maybe a lowpass or bandpass filter, and an adjustable gain/attenuation stage, then mix that path back into the input to the guitarix plugin. Essentially attempt to recreate the acoustic path within Ardour. You could maybe do the feedback self-contained, not going back through the input of guitarix (or whatever amp simulation is being used), but I suspect that the character of the sound would be quite a bit different if the feedback didn’t go back through the (simulated) guitar amplifier.