...

Measurements

What is a spinorama set of graphs?

It is a way to understand quickly a speaker properties, how it will sound. It is defined in this standard from the USA CTA. Here is an example:

spinorama from a Genelec 8341A

The spinorama gives you a few graphs:

The speaker above is very good. You can compare with another one:

spinorama for a Tannoy XT6

which is not flat at all. Remember that ±3dB means that the volume doubles/halves at the corresponding frequency. If you look at the on axis measurement below, you see that it going up, the speaker will likely be bright and emphasis high frequency.

On Axis for a Tannoy XT6

Please tell me more:

If you like to read: If you prefer to watch: There is a fine set of videos from ErinsAudioCorner on Youtube:
  1. What Is Frequency Response? || Understanding the Measurements Part 1
  2. Off-Axis vs On-Axis Response || Understanding the Measurements Part 2
  3. What the heck is SPINORAMA?! || Understanding the Measurements Part 3
  4. Predicting Loudspeaker Performance In YOUR Room || Understanding the Measurements Part 4
  5. Loudspeaker Compression || Understanding the Measurements Part 5

FAQ

Can I trust the data?

The measurements are collected on the internet. Some are of very high quality and done by independant reviewers, some are of medium or low quality or provided by vendors.

You can filter the results by clicking the wheel on the website near the search bar.

How to filter on high quality measurements

How precise are the measurement data?

How precise are the computed data?

Can I use this data to decide which speaker to buy

See dedicated section.

Should I use room EQ?

Absolutly! Dirac, REW, Audyssey etc will provide audible improvement to the sound, in general making it flatter (so more tonally correct).

Focus or broad radiation pattern?

Speakers do not radiate uniformly. Some speakers are designed to be very focus: they minimise the reflections but the sweet spot is very tiny. Some speakers are designed to diffuse sound, research proved it is something that people usually like. If you are near field, for example on a desk, low directivity works well. The farther from the speaker you are, the more good directivity becomes important. If the room is reflective, this is especially important.

How can I help?

  1. This website is generated from this code and data from various websites (see below).
  2. You can provide feedback or add more datas at github or in this thread at ASR.

How to select your speaker?

That is a polemic section, I know, I know.

Criteria

I believe there are a few criteria in whatever order you want:

How good is your room?

If you did not answer yes each times, then you do not need the best speakers in the world and obsessing over scores, SPL etc will not make it the best room in the world. At the same time, I understand very well the attraction of having a great pair of speakers. Speakers with a high tonality score will be easier to EQ and will adapt well to your room. Define the SPL you want (at 1% distorsion) and now you have reasonable choices.

Source of data and citations

  1. AudioScienceReview aka ASR: it is a fantastic source of speakers data thanks to amirm@. They also have a lot of data about DACs that you may found useful. There is little correlation between price and quality in the audio world and this data gives some objective criteria to decide what to buy. You can support ASR.
  2. ErinsAudioCorner aka EAC: Hardis is a motivated person reviewing speakers. He is doing an outstanging jobs. He also has a Youtube channel. You can also support him.
  3. 3D3A is a research organisation at Princeton:
    • They provide a database of speaker measurements (manual)
    • Some scientific papers I have used:
      • Metrics for Constant Directivity (abstract, paper, poster) Authors: Sridhar, R., Tylka, J. G., Choueiri, E. Y.; Publication: 140th Convention of the Audio Engineering Society (AES 140) ; Date: May 26, 2016
      • A Database of Loudspeaker Polar Radiation Measurements (abstract, )
      • On the Calculation of Full and Partial Directivity Indices (abstract); Authors: Tylka, J. G., Choueiri, E. Y.; Publication: 3D3A Lab Technical Report #1; Date: November 16, 2014
  4. speakerdata2034 is a blog with a collection of spinorama from various sources. Index of measurements is available.

Books and research papers