Directivity Reference for System Design

by Pat Brown

The key to working in the field of audio and acoustics is to understand the need to establish a reference condition. This allows changes to be assessed objectively. You need a “known” in order to determine unknowns.

An effective site survey is driven by getting the most information in the least amount of time and with the least amount of gear. If one is clever, they can acquire a meaningful set of room data, with very little site time. That’s important, because there’s never enough time. (more…)

Really Good Hook-up Wire

 

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Hook-up wire is an insulated single conductor. It is often used for short point-to-point connections within components, racks, electric guitars, etc. A little trick I have used for years is to twist two diffehookuprent colors together to make unshielded twisted-pair (UTP) cable. Just play out a few feet and fasten the ends in a vice. Fasten the other ends in a battery-powered drill and twist as tightly as you please.

I recently discovered a really nice hook-up wire designed for use in electric guitars.

From the website: 22 AWG unshielded single conductor wire is tinned and stranded, with a white celanese wrap and waxed braided cotton outer insulation. The cloth insulation simply pushes back to expose the center conductor wire.

Since it is both stranded and tinned, two strands can be combined to form an especially tight twist that doesn’t untwist itself due to memory effect. For soldering to connectors, just push back the insulation – no stripping required.  pb

Photo Below – The twisted-pair is tight and retains its shape, right up to the connection point.

adapter

So…Wiki is not Lucy’s husband???

By Jim Sorensen

 

This use of unsupported sources happens all the time, particularly in the media itself.  How often have you heard someone on TV say that the bloggers are reporting such and so?  Bloggers?  What the heck is a blogger and why does a bloggers opinion count more than mine? (more…)

War Tuba

First impression, it looks like a loudspeaker. It is actually a mic.

Acoustic location devices were used by military services from mid-World War I to the early years of World War II for the passive detection of approaching enemy aircraft by listening for the noise of their engines. These typically consisted of large acoustic horns attached to stethoscope-type earphones worn by monitors. This technology was rendered obsolete before and during World War II by the introduction of radar, which was far more effective.