stevie

[quote name='redstriper' timestamp='1377720809' post='2190944'] I'm sure they shouldn't sound so good on paper, but they work for me and all those who have used them - that's not to say they would suit everyone. [/quote] If they are a plywood sandwich with foam in the middle, that does sound good on paper.

[quote name='Mr. Foxen' timestamp='1377720598' post='2190937'] All of this doesn't ring true. You absolutely can compensate for the reduced self damping of thinner materials, changing the ply composition can do that. additionally all the stiffness stuff doesn't work, half the panel thickness and brace across two opposing panels will happily give most of the stiffness of an unbraced full thickness one, along with massively reduced resonance/raised resonant frequency. Observing any engineered structure shows specific reinforcement is employed over plain mass, any large concrete structure isn't just made of masses of concrete, it is made of reinforced concrete, with an interior framework giving strength with concrete over it. Bridges are not made of a solid mass, but a framework of supports. [/quote] You know what doesn't ring true? The idea that you can keep making material thinner and thinner and by adding bracing maintain the same properties as thicker material. It's b*llocks. Otherwise, we'd all be using cabs made out of 3mm MDF. What does changing the ply composition mean? And yes, bridges are designed for rigidity. But they are made from strong materials to begin with, i.e. reinforced concrete or steel. You don't design a bridge by making a structure that is as light as possible and then reinforcing it with bracing, now do you? By the way, have you any idea how stiff a church bell is?

[quote name='Phil Starr' timestamp='1377403675' post='2187129']Like Stevie says there are two ways to save weight. Mass is one of the things that affects panel resonances, stiffness another and there are more, there is nothing new in making thinner speaker panels and bracing and damping them or even looking at alternate materials with different mass/flexibility/internal damping. Bracing any panel will reduce it's resonance and shift the frequencies involved. The lightweight cabs may use 12mm panels rather than 18mm saving 1/3 of the mass. Then use some of this saving to create the bracing, they may even then be more rigid and less resonant than a conventional cab.[/quote] Whilst theoretically possible in an ideal world, getting a 12mm panel as stiff as an 18mm panel requires some serious bracing – enough to make the box nearly as heavy as making it out of 18mm in the first place. The way I remember it, if you reduce the thickness of plywood by 3mm you reduce its stiffness by 50%. So a 15mm panel is half as stiff as an 18mm panel and a 12mm panel is half as stiff again. An 18mm panel is actually 8 times as stiff as a 9mm panel – and it's a lot worse if you're also using lighter materials like softwood ply. I don't think any of the companies making lightweight bass cabs are using a really sophisticated bracing system like the B&W Matrix because that would add too much weight. These companies are building lightweight cabs – so they use as much or as little bracing as they need to get the job done. The only company that provides any information on their cabinet bracing is Trace Elliot and they seem to be using a single circular brace. Good, but not belt and braces, although to be fair they don't make any special claims for their poplar ply cabinet anyway – except that it's light. Although in theory you can brace the bejaysus out of a thin panel to make it stiff, what you can't do is compensate for the reduced self-damping of thinner materials. Damping is what stops a material from ringing - and ringing is what makes cabinets sound bad. There's also the problem that the thinner material is less acoustically transparent and will allow sound to escape through the cabinet more easily at certain frequencies. So while I'm all in favour of neo drivers, I am not a fan of thinwall cabinets for bass. You can easily check the inertness of your cabinet (and thus how much spurious noise it is producing) by playing a low E on your bass whilst placing your (other) hand against the back panel.

As long as it fits in the hole, there is very little that could go wrong. Use some foam gasket round the Celestion when you fit it. Be VERY careful with the screwdriver - they have a tendency to slip off the screws and through the cone.

[quote name='RandomBass' timestamp='1377344307' post='2186485'] I wonder if BF are available on the NHS? [/quote] We should all lobby our MPs!

You can buy an Ashdown 1 x 15 for about £150 on here. Even brand new they're ony £350. What's a Compact - £700?

[quote name='alexclaber' timestamp='1377267953' post='2185624'] Yes you are! [/quote] Well I was only guessing but you certainly appear to have a lot of customers with bad backs.

There are two ways that the manufacturers of these lightweight cabs make them lighter. The first is by using drivers with neodymium magnets. These are equivalent in every way to the more familiar, heavier drivers and the weight saving is made possible because of a technological advance. Neo drivers are roughly half the weight of their ceramic equivalents. They are also twice the price. The second way of reducing overall weight is by reducing the weight of the cabinet. Because there is no technological advance involved here (such as carbon fibre panels, for example), manufacturers make the cabinet walls out of thinner or less dense materials to get the weight savings. It's fairly obvious that this is not ideal, because the cabinet is going to 'talk' when pounded with bass frequencies, but many people are prepared to accept the compromise to get the light weight. I may be wrong, but I have the distinct impression that most of the people buying these have bad backs. The PA industry went throught a similar kind of thing several decades ago when the plastic PA cab was introduced. Most of them make the singer sound like he is singing in a bucket, but they remain popular - especially with female vocalists. It interesting to note, however, that PA bass bins are almost without exception made from 3/4" stock because that is what has proven over many years to be optimum. A good, modern conventional cab will always outperform a modern 'lightweight' cab of equivalent price - especially at volume.

The 1.5V NiMH batteries I have only charge to a maximum of about 1.3V in practice but I get up to 10V from my 9V ones when they are fully charged.

And what would you think of a builder who insisted that you paid in full a month before he started the job? I'd tell him where to put his spirit level and I'd find someone else.

[quote name='alexclaber' timestamp='1376572694' post='2176245'] Regarding finish related things, if we switched to 1/2" ply then the front corners would be easier to fit because of the larger edge radius but the bare enclosures would then be about 1/2" bigger in all directions and would weigh 30% more without sounding any better. [/quote] Just out of interest, are you using 8mm akoume all round?

I suspect that Chris is concerned you might overload your cab - which you might. However, if you find it perfect apart from the very low end, it's certainly worth trying a couple of dBs lift around 50 to 60 Hz with a suitable equalizer - one that gives you a relatively narrow boost. I'd be wary if it needs much more than that.

What's wrong with the wheels - are they too small? I have 3" castors on my cab, and they're not great.

Mr Foxen's right, but why can't you eq some more bottom-end welly in?

Whilst that's true, sk, I don't think the handles are actually failing, are they? That would be quite serious.

What's that supposed to mean?

[quote name='Happy Jack' timestamp='1376293079' post='2171673'] Sorry Stevie but the more extreme the view being expressed, the more likely it it to attract criticism. Toasted's wild exaggeration may well be his point of view (and he is of course perfectly entitled to exaggerate as freely as he likes) but he can hardly be surprised to find that some of us are not inclined to let such nonsense pass without comment. [/quote] I thought you replied to his comment rather well but there was no need for the ad hominems. I know these tend to slip out, but they are not conducive to open discussion - especially when they are thoughtlessly repeated by others. Toasted may have over-egged the pudding a bit, but he made a reasonable point: if you are going to charge premium prices for your product you shouldn't be fitting them with a cheap handles that don't last.

[quote name='discreet' timestamp='1376250926' post='2171377'] As that view has already been expressed, surely this is a moot point. [size=4]I have the right to reply to any comment, just as you do.[/size] [/quote] You didn't actually reply to the comment though, did you?

[quote name='discreet' timestamp='1376241252' post='2171206'] [size=4]Given the level of intolerance, surely The Daily Mail would be more appropriate?[/size] [/quote] A remark which itself betrays a distinct lack of tolerance for the rights of others to express a view.

[quote name='Ashdown Engineering' timestamp='1376076703' post='2169560'] Decent wasn't good enough for ABM Neo and therefore we have gone the extra mile in every respect when designing and manufacturing these here in Essex. [/quote] Good for you! Can we expect cast chassis and wadding in the cabinet of these new speakers?

It does look good! Ashdown cabs have never been state of the art but they have always offered really good value for money.

I arranged carriage for an item which was damaged due to really poor packaging. The seller insisted I should claim from the carrier even thought he was obviously at fault. I won my claim through eBay, got my money back and kept the goods.

I'm not sure you'll hear a huge difference, Dood. Seymour Duncan used to make a valve guitar amp called the Convertible which had a damping factor control knob. It worked and you could hear the difference, but it never caught on. For bass, I like an amp to have tight control over the speaker myself. If I need a bit more warmth I can always get it using the tone controls. However, Matrix obviously believe it's a good idea for guitar, and they seem to know what they are doing.

According to the designer, they reduced the damping factor to simulate the looser kind of tone you get from a valve amp. That could work for bass but I think a normal design power amp might be better.

Fascinating. Apart from the Musicman (which sounds different), the others are so close in sound that it would only take a tweak of eq to get one to sound like another. I liked the Fodera followed by the Yammy. The SX sounded a bit thin to me. There's a lesson in there somewhere.