Recent content by JohnPM

Best is to measure each speaker separately with a timing reference. To see the behaviour with both speakers active the measurements can then be summed. The main issue with multiple speakers running is comb filtering at high frequencies due to path length differences to the mic. At low...

If only "passive" meant "good", but it doesn't. In passive crossovers: The components dissipate (waste) significant amounts of the power delivered from the amplifier The need to handle high powers makes it difficult to produce components with well controlled tolerances, so the crossover...

If you don't like all those transistors in the signal path you are a prime candidate for DSP, just digitise at the front end and do it all in the software, or to get even closer to the real signal feed the source's digital data straight to the DSP. You must have a digital source, right, what...

A very long time ago I had a pair of Stax Lambda Signature headphones driven by their valve energiser of the time, SRM-T1 I think. Sounded pretty spectacular to me. Stax for a time had an equaliser for the Lambdas, the ED-1. I got one to try, it made a surprisingly large difference, though I had...

Back in the day John Atkinson felt that even 0.5 dB changes in parts of the frequency response made big differences to the perception of music.

If you have perfect left/right symmetry of sources along the length the odd order width modes cannot be excited as they are driven in equal and opposite phases by the sources either side of the mid line. A pair of speakers doesn't quite achieve that, unless they are halfway down the room, but...

Still have a pair of SCM10 in a cupboard upstairs, they like a sturdy amp.

Not for low frequencies. Neither has much absorption to speak of at high frequencies. Random-incidence absorption coefficients

They make fun desktop speakers :)

Stretching your budget, but the Genelec 8331A can be found for £3.5k/pair.

White noise puts more energy in the tweeters, keep the levels down if you use that.

Seems to be a big offset from zero at the start of that response.

The way the frequency response changes off axis, there are a few ways to define it - Nyal Mellor covers them in this article.

The speaker's directivity can't be altered by processing of the signal sent to the speaker, so the character that imparts to the sound remains.

There is little difference at high frequencies, that is a misinterpretation of the equal loudness curves (one commonly reflected in the loudness compensations that used to be more common). What matters is not the shape of the equal loudness curves but the uniformity of the gaps between them, at...