Room Acoustics

Complex bass array –

In my last TestHiFi blog I wrote about a band-limited low frequency (LF) system to fill a response gap. This time I would like to show a much more complex LF system. Some years ago […]


An unconventional loudspeaker solution for LEWITT Audio

An unconventional low frequency solution – LEWITT Audio The result
shows the advantage of this remarkable space: walking back along the symmetry axis towards the rear wall without any change of LF characteristics. Nice and even everywhere!
LF reproduction can be tricky, even in an amazing room like this. One more reason for custom design 🙂


Absorption and Diffusion – Lemon Audio

How do we achieve good room acoustics? Today, it seems there exist some guidelines about how to design a good loudspeaker.Interestingly, we find much more controversy how to achieve good room acoustics! For loudspeaker placement […]


Phase and Time 2

 Text to speech  –  TestHiFi blog: Phase and Time 2 The system that shouldn’t work well – phase and time completely ignored! Last time I wrote about phase and time issues of loudspeakers. A result […]


Listening Position Measurements

Measurements at the listening position are nice to achieve a quick „objective“ sound quality documentation of an audio system. Let’s have a look at the basics. John Atkinson of Stereophile magazine keeps a certain procedure […]


Midrange Room Influence

The room influences midrange frequencies with a mix of modal and interference based effects. Allow me to declare the midrange frequency (MF) range to reach from 100 Hz to about 2 kHz. This is the […]

David   Room Acoustics

High Frequencies (HF) – More Questions Than Answers

The picture on top shows 100 ms of the room response after an initial impulse was radiated by the loudspeaker. Since low frequency (LF) energy is distributed over time what we see is mostly high […]


Modal coupling – aka Low Frequency Optimization

Modal coupling is about how your loudspeaker’s and listening position influence the reproduction of low frequencies (LF) in your room. Fundamental frequencies We have been talking about room modes in the resonance blog. At a […]


Resonance, standing waves and room modes

Room modes Resonance happens in systems that can oscillate. Rooms are such systems, and their resonances are called room modes. Loudspeakers excite these room modes more or less depending on their position, creating so-called standing […]