# sumFX — Modular Multi-FX Processor

> Modular multi-FX audio processor for creating unique sounds on Mac/PC and iOS. (iPhone/iPad app by OSC Audio.)

- Source: https://appshunter.io/ios/app/sumfx/id6450494474 (this page in markdown: same URL + `.md`)
- Developer: [OSC Audio](https://appshunter.io/developer/1693533681)
- Category: Music, Entertainment
- Price: $9.99
- Rating: 4.40/5 from 12 App Store ratings · 11 written reviews indexed
- Age rating: 4+
- Requires: iOS 12.0 · 44 MB
- Released: 2023-07-15
- Data updated: 2026-08-25
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/sumfx/id6450494474/reviews.md

## What is sumFX?

sumFX is a modular multi-FX processor for Mac/PC and iOS. Designed with simplicity in mind, to help keep you focused on the music and the sum of your efforts.

Packed with 8 high quality FX modules and an available 8 slots, each loaded with Wet/Dry control, Global Wet/Dry, and 2 LFOs per slot, creating new unique sounds is quick and easy.

50+ cross-platform slot & chain presets are included to get you to any sound you need quickly and we’ve packed in an easy to use pre/post waveform view to help keep you focused on the result of your FX.

Modules:
-syncDynamics - Multimode dynamic FX with BPM sync attack/release (Noise Gate, Expander, Compressor, Limiter)
-stereoFilter - Stereo filter with link or individual channel controls (LPF12, HPF12, BPF12, LPF24, HPF24, BPF24, Notch, & Formant options).
-variMod - Multimode modulation FX with stereo offset (Chorus, Flanger,  Vibrato, Phaser, Tremolo,  & Auto Pan)
-EQuator - Full high quality EQ module (3 Parametric Bands, High/Low Shelf, & HPF/LPF).
-frostReverb - Multi-Mode (Original, Plate, Spring, Room) Stereo Reverb. 
-bucketDelay - Stereo Analog Style Delay with individual channel control.
-variPitch - Stereo Pitch Shifter with 3X Modes (Doubler, Harmonizer, & Full Control)
-powerPhase - Multimode Saturation, Utility Gain In/Out, Mono Maker, Channel msDelay, & Phase inverter.

## Key features

- Modular multi-FX processor
- 8 high-quality FX modules
- 8 FX slots with Wet/Dry control
- 2 LFOs per slot
- 50+ cross-platform presets
- Pre/post waveform view

## Recent user reviews (10 of 11)

All indexed reviews: https://appshunter.io/ios/app/sumfx/id6450494474/reviews.md

### 3/5 — Could use apple silicon optimization.

*2024-08-09*

Update to perform better on apple silicon please!

### 4/5 — Menus work fine at last !

*2024-07-17*

After a looooong time, the app is at last usable! Good work! I have retired my last two stars review. I will give you the last star when I can assess the app, since I haven’t manage to use it so far. Congratulations!

**Developer response:** As much as it hurts to hear your experience here, and see your negative review here, we appreciate your feedback. We'd love to hear which menus are causing your troubles to help improve the app in any and every-way possible. 

Please contact us directly at our support email (below). 

contact@oscaudio.com

Note, when you have an FX turned off, the LFO and FX Mode options are disabled by design. This might not be what you're referring to, but we wanted to make sure this was mentioned. In the update I've made sure to have "FX OFF" listed for each of the disabled menus to make sure it's clear when these are not selectable.

Best,
Your OSC Audio Team

### 5/5 — I use this all the time.

*2023-11-26*

This is one of those apps that I always go to. There are apps you buy and just forget about them after awhile. That’s not the case with this one. I can’t wait to see what OSC Audio comes with next. Please make some instrument apps like a synth or a drum app. I know you can make something great.

### 1/5 — Dont pay this crush vst3

*2023-10-19*

It doesn't work when you sample the sound or output the finished result.

### 5/5 — Thanks for updating

*2023-08-29*

Now it is great. Thanks for doing the updates.\ and responding. Now can use it in a way that is doable since there are loaded presets.  Tried changing to 5 stars hope it worked.

**Developer response:** Edit: The update is live! :) Thanks for your patience. My BETA team caught a really tricky last minute issue that’s been fixed.

Thanks for your review, I appreciate your time and support.

I can confirm, you've heard right! The preset use in app is getting a whole redesign in the next update. I've worked with some really helpful users to make sure it's a quick and easy to navigate.  I'm not sure if Apple allows links to video example, but here is an unlisted (early) sneak peek of the preset manager.

https://youtu.be/QXUBQxt7QII

This update is planned for next week, it's almost complete. It's in testing now and getting the final cherries on top.

Don't hesitate to let us know what else you'd like to see in the update. Below is our direct contact link.

contact@oscaudio.com

In the meantime, I've made a quick video to help make the current system as useful and easy as possible. Link below (hopefully Apple lets it through). 

https://youtu.be/xnbsG5WC4-4 

Thanks again for your support!

### 1/5 — Crash

*2023-08-09*

On my ipad air 2 crashes at every opening tentative. Impossible to use it. Why?

**Developer response:** We're very sorry to hear of your behavior here. That is very unfortunate to hear. Since, I have not had any reports of this other than your review, I'd like to take a closer look to see what could be going on 

If you could reach out to our team at the email below that would help us see what we can do to get you working and prevent any future users from ever encountering the same behavior. contact@oscaudio.com

I can say there is an update coming very soon, so stay tuned as this comes with a lot of iOS based improvements including CPU optimizations and a couple of useful features like easier preset navigation.

Striving to get that 1-Star up to 5-Star, we hope to hear from you!

Best,
Your OSC Audio Team

### 5/5 — Read description!

*2023-07-25*

I’m editing the previous review, actually I don’t think I need the manual anymore, it’s just a couple of pages of description that’s it, just realised, it’s the sound that matters, doesn’t matter what or where it’s inspired from, from a very pragmatist point of view.

So, here comes the new king of the iOS, 
All hail the the king! 
The king has arrived!
All hail the king!

With love and lots of respect and hugs, 
welcome, Sire!

This was the previous review, please kindly ignore this to save up your precious time brother

“I know you’ve been working hard, with passion and sincerity, but the thing I want to point out, or a question to ask. What is the purpose for the manual you’ve come up with, even with putting my all biases on your side, the manual doesn’t have any real information regarding the app, what kind of modules , their emulation background, at the very least the hardware inspiration behind the emulations, I mean I could go on. This manual is going to have a great impact on your reputation. Please, my friend, don’t take this personally, consider this a friend who truly cares about another friend of his, and suggest him to only help him. He who always praises you, beware of them. Only true friends will tell your lacking to you, no other entity will do that. With kind regards. Giving 5 stars , just to show respect for the hard work, and artistic creativity you’ve put into this bomb of an app.”

**Developer response:** Thank you for your kind words and 5-star review. Constructive criticism is never taken negatively and your words are not taken lightly. I want to make sure users get the best experience and I'll be updating the user manual asap to make sure I get all the details I can added.

If there are any topics you want covered specifically, let us know. Feel free to reach back out here or via our contact email. We greatly appreciate user feedback and we look forward to getting you what you need to create without restriction.

Thanks again for your feedback and support! Stay tuned for the next update. We'll have some news soon.

### 2/5 — Ehhhhh - needs improvement

*2023-07-19*

Sound quality is alright. The UI seems to suffer some lag from when you move the knobs to actually hearing the change. I feel like I can get most of these sounds in higher quality from other plugins, but it could be useful if they add some more algorithms, better reverbs, etc.

**Developer response:** Thanks for your feedback, we appreciate your support and we're sorry to hear of your troubles. 

We'll be adding a lot more to come in future updates. If you experience any issues, please be sure to report your device information to our team for full investigation. 

Below is our support link.

contact@oscaudio.com

### 5/5 — Excellent, enjoyable and a great idea

*2023-07-18*

This is perfect for me, easy to use and all in one place. On top of that it sounds great to me and some very experimental and interesting things can be achieved here. All good 👍

**Developer response:** Thanks for your support & feedback that means a lot! 

We're very happy to hear sumFX is treating you right and helping you make new music.

Enjoy!

### 3/5 — Cool idea, not quite there yet

*2023-07-17*

Needs some presets to be more useful. Lfo Sync options seem to have a mind of their own as to when changes kick in. And having to engage transport to hear is a pain.

**Developer response:** Thank you for your feedback. 

We're working on the behavior of the combo boxes, it seems on some devices it's easier than it should be to move your finger off the selection upon release. This prevents the selection and might be what is happening to you. Stay tuned! 

Make sure to have your FX engaged with the power button at the bottom of it's slot when changing Modes/LFO options. 

As for your last behavior with the transport, that will be resolved in the next update. :)

## Frequently asked questions about sumFX

### What is sumFX?

sumFX is a modular multi-FX processor designed for Mac/PC and iOS. It allows users to create unique audio sounds by combining various high-quality effects modules within customizable slots.

### What kind of audio effects are available in sumFX?

sumFX includes modules like syncDynamics (gate, expander, compressor, limiter), stereoFilter, variMod (chorus, flanger, vibrato, phaser, tremolo, auto pan), EQuator (EQ), frostReverb, bucketDelay, variPitch, and powerPhase (saturation, utility).

### How many FX modules and slots does sumFX offer?

sumFX comes packed with 8 high-quality FX modules and offers 8 available slots for them. Each slot includes Wet/Dry control, Global Wet/Dry, and 2 LFOs per slot.

### Does sumFX include presets?

Yes, sumFX includes over 50 cross-platform slot and chain presets to help users quickly achieve desired sounds. It also features an easy-to-use pre/post waveform view.

### What devices does sumFX support?

sumFX is available for iPhone, iPad, and iPod. It is also available for Mac/PC.

### How much does sumFX cost?

sumFX is a paid application priced at $9.99. There are no in-app purchases or subscriptions mentioned.

### When was sumFX last updated?

The latest version of sumFX, 1.1, was last updated on July 16, 2024. It was initially released on July 15, 2023.

### What is the age rating for sumFX?

sumFX has an age rating of 4+, making it suitable for a wide range of users.

## Version history (last 3 releases)

### 1.1 — 2024-07-16

-Reorganized GUI for easier access of all available functions
-Added Drag & drop swap functionality for Slot FX
-Added Zoom + / - and Mono/Stereo options for Waveform view
-Quicker Preset Management (no more slow File Chooser!) & submenus for easier navigation
-All Factory Presets redesigned and new Presets added
-New “Smooth” Saturation mode in Utility for unique harmonic enhancement
-Improved downsampling algorithm for Bit Crusher in Utility
-Modulation FX improved response, increased range & BPM sync added to all modes
-Delay DSP redone for smoother, tape-style rate changes 
-3 Reverb Modes Added Plate, Spring, Room (in addition to the original “Original”)
-Equalizer Gain, Frequency, & Q now assignable to LFO 1 & 2
-Dynamic Meter now shows GR (Gain Reduction) value
-General DSP overhaul for smoother parameter changes 
-Completely refactored LFO section for better reliability
-Improved Utility Meter Module for RMS & Peak Value Display
-Fixed BPM calculations to be in real time & fixed triple/double value inconsistancies
-Fixed Dynamics potential to open with 0 Attack/Release causing no output
-Fixed Reverb GUI screen element centering going too far with larger size options.
-Fixed potential recall issues with Presets & Sessions (Warning! Older presets might need to be re-saved and might load slower the first time after update)

### 1.0.7 — 2023-08-27

-New preset load drop down lists for Slot and Chain
-New preset load drop down lists for Slot and Chain
-New preset save added next to save as for Slot and Chain
-New preset next/previous for Slot and Chain 
-New tutorial on first launch 
-New Link control for Input/Output gain inside powerPhase (Utility)
-New iPhone (only) view selections for LFO, FX, or FULL view for easier usability
-Refactored LFO/Mode sections for easier selections & more efficient CPU -
-Warning added to LFO/Mode to remind users when FX OFF
-Corrected missing check boxes in Audio Setup (Stand alone only)
-Corrected Delay reaction when Link engaged/disabled
-General reliability improvements

### 1.0.2 — 2023-07-16

No release notes.

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## More apps by OSC Audio

- [BFM - Metering Suite](https://appshunter.io/ios/app/bfm-metering-suite/id6450574108)
- [plateVerb](https://appshunter.io/ios/app/plateverb/id6450970583)
- [springVerb](https://appshunter.io/ios/app/springverb/id6450971173)
- [pocketOscilloscope](https://appshunter.io/ios/app/pocketoscilloscope/id6450971969)
- [pocketOSC](https://appshunter.io/ios/app/pocketosc/id6450972460)

All apps by OSC Audio: https://appshunter.io/developer/1693533681

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-25.*