Comparison

Sirens' Chor vs ERS_DimD

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Sirens' Chor

This experimental audio effect app analyzes input audio to generate a secondary harmonic voice using sine wave oscillators. The generated voice can be mixed with the original or played solo, creating a chorus effect. It's CPU intensive and operates within a specific frequency range.

Highlights
  • Harmonic analysis of input audio
  • Sine wave oscillator synthesis
  • Adjustable chorus effect
  • Second voice generation
  • AUV3 plugin support
Features
Read full description

This one is quite experimental and CPU heavy app! While working on my Chord Detector app I came up with the idea to play the found harmonics with sine wave oscillators so I can hear what the algorithm is hearing :) It turns out to be an interesting output that led me to creation of this audio effect app. What happens here is that the input is analysed for main harmonics in the range of 80Hz to 1500Hz. Then a series of sine wave oscillators are set to play those harmonics with the exact frequency and volume and their output is added to create a second voice. This second voice can then be mixed with the input to create some kind of chorus or played alone. All this is CPU heavy process so it should be used with care... Also to make this effect possible I had to use limited range 80Hz to 1500Hz so it is not suitable for every instrument and you have to keep that range in mind when producing. Some very fast volume and frequency changes are applied to the oscillators. The app is AUV3

About

ERS_DimD

This audio plugin emulates the classic Roland Dimension D chorus effect, known for its subtle, airy stereo enhancement. It adds presence to sounds without compromising the original audio structure. Enhanced controls offer more flexibility than the original hardware.

Highlights
  • Emulates Roland Dimension D chorus
  • Subtle stereoizing effect
  • Adds presence and airiness
  • Enhanced control options
  • Preserves original sound structure
Features
Read full description

The ERS DimD chorus audio plugin was originally designed and sold by Harrie Munnik and his Dutch company EmptyRoomSystems. DDMF is proud to carry on the legacy by distributing and further developing the set of ERS plugins. This plug-in has been developed to sound like the Roland Dimension D Chorus with enhanced controls (a hardware chorus that has been used on thousands of recordings worldwide). It has its own signature sound: it is famous for delivering a subtle, stereoizing enhancing, airy effect while adding more presence to a sound. Most chorus products give a lot of modulation and do not keep the original structure of the sound intact. This chorus is way more subtle and adds something rather than take away the original quality of the sound.

Screenshots

Sirens' Chor3 screens
ERS_DimD2 screens

Verdict

The call

The clearest difference is price: Sirens' Chor at $3.99 against ERS_DimD's $9.99. ERS_DimD's advantage is update cadence (every 8 months vs every 39 months). On rating, review sentiment, ratings volume and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Sirens' Chor costs $3.99 and ERS_DimD $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.0 for Sirens' Chor against 4.0 for ERS_DimD. Both are backed by a comparable volume of ratings — 2 and 5 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

Sirens' Chor ships an update every 39 months, ERS_DimD every 8 months. Both last shipped on November 3, 2026.

Scorecard2 real differences · 8 level
Sirens' Chor versus ERS_DimD: the parameters behind the verdict, then further details
ParameterSirens' ChorERS_DimD
Price$3.99 — better$9.99
Rating4.0 (2 ratings)4.0 (5 ratings)
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings25 — better
Update frequencyEvery 39 monthsEvery 8 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS10.09.3 — better
Further details — not scored
Size11 MB7 MB
Age rating4+4+
DeveloperAleksandar MlazevChristian Siedschlag

Customer experience

Sirens' Chor

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

ERS_DimD

All ratings5 ratings
Positive80.0%
Neutral0.0%
Negative20.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Sirens' Chor

No in-app purchases

None

ERS_DimD

No in-app purchases

Questions

Is Sirens' Chor free?
Sirens' Chor costs $3.99, with no in-app purchases.
Is ERS_DimD free?
ERS_DimD costs $9.99, with no in-app purchases.
Which has better reviews, Sirens' Chor or ERS_DimD?
Sirens' Chor and ERS_DimD are both rated 4.0 out of 5 on the App Store, from 2 and 5 ratings respectively.
Do Sirens' Chor or ERS_DimD have ads?
Neither Sirens' Chor nor ERS_DimD shows ads.
Which is updated more often, Sirens' Chor or ERS_DimD?
Sirens' Chor ships an update every 39 months, and ERS_DimD every 8 months. Most recently, Sirens' Chor was updated on November 3, 2026 and ERS_DimD on November 3, 2026.

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