Terry's two stage Cubix Pro build

[Dr Bunsen Honeydew]

A chronicle of the build.

Power supplies loaded, doped, but not wired yet.

[applemarc]

You will like these Terry

[terrybooth]

I fully expect to. I heard yours while they were at the Docs.

[jammy395]

Ace of Spades - Motorhead - Vol 11........

[terrybooth]

More like Das Rheingold or Mozart.

[Dr Bunsen Honeydew]

Their job is not loudness Jammy. Anyway as I have said many times before loudness is a factor of distortion, nothing else. I could make you a 1w amplifier that would sound loud and I could build you a 1000w amplifier (already have in the Tresham SR402) that wouldn't sound loud until your ears were bleeding. If you drive an NVA amp to the point you wince and say "that is loud" then your nearing the destruct button. Sounding powerful and sounding loud are two different things. Being pinned to the back wall of a broom cupboard by Tannoy PA speakers, driven by a pretend class A valve amp being overdriven, is supposed to impress some people, well it will if they are ignorant.

The Pros will give you scale and power, if they sound loud then something is wrong.

[Dr Bunsen Honeydew]

Some extra inf on the subject.

One of the things that tells our ears that a sound is loud is distortion. When amplifier circuits are driven into distortion, they create high-frequency harmonics of the original sound. The extra high-frequency content makes the sound seem louder. Also, when an amplifier reaches distortion, its dynamic range is reduced: although the quietest sounds it reproduces are increased in level, the loudest sounds it can reproduce are limited by its output capability. This will also make it seem louder. These two factors combined can make an amplifier with limited power driven to distortion seem louder than an amplifier with greater output operated within its limits.

Some inexperienced guitarists will set the level of an ‘overdriven’ channel at a lower level than the ‘clean’ channel. Without any other cues, the distortion of the ‘overdriven’ sound makes it seem louder, where a meter shows it is in fact lower in level.

From - http://www.astralsound.com/loudness.htm a good article by the way as PA companies have to understand this and are not subject to the bullshit hi-fi users are.

[terrybooth]

The build has arrived at something of a crossroads (not that I ever mix my metaphors). Cubes/Cubix/Cubix Pro have previously been built with the same size cover over the tweeters (facing forward and to the side) as the top firing Bass/Mid drivers. But should the tweeter have a smaller grill? Below is a mock up based on my Cubix. You have to use a bit of imagination because the size of the tweeter will remain the same.

The way they are built now

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the way they might be built

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[slinger]

Will the grill surround be the same thickness or will that be scaled down too?

[Dr Bunsen Honeydew]

Surround is the same, hole size in the mesh is the same. I have 10inch (Cubix Cubix Pro and Cube1), 8 inch (Cube2) and 6 inch(Cube3 and Cubettes) versions. The bass/mid driver needs the 10inch and I have always used that for the tweeter in the Cube1 Cubix and Pro, but was looking at it and couldn't make up my mind if Terry's 2 part pros would look better with either of the smaller grilles on the tweeters. So I have left it up to him.