stevie

The Beyma is a great choice. Here are the parameters, which have been cross-calculated and shouldn't throw up any errors. I'd pick the size of box you want rather than letting WinISD do it for you. 50-litres would be a good starting point. Tune between 50 and 55Hz using (preferably) a single 100mm dia. or else 2 x 70mm ports. [IMG]http://i48.tinypic.com/n1rpmo.jpg[/IMG]

I wouldn't buy a bass cab without Speakons nowadays. Unless you're getting a really good deal or are in a hurry, I'd wait. It's your money. Edit _ If it's jacks only, it will probably be pretty ancient - also worth bearing in mind.

Phil, the reason I mentioned frequency response is that I've never seen it discussed on here before. I just wanted to put a word in for the Celestions because everyone on BC seems to automatically favour Eminence, whose products really are a very mixed bunch. In a typical 12-inch cab the green Celestions (the BL-200X ceramic and BN-300X neo) model exactly the same as the Beyma at the bottom end (and the Eminence Beta 12 in fact). So they're going to have a full, warm bass sound. I've never seen the point of the Orange series because 1. their xmax is limited, as you rightly point out, and 2. because they roll off early when you load them in a box and will sound quite thin (very similar to the Eminence 3012HO which is not an ideal bass guitar speaker despite Mr Foxen's eulogy). However, they may work better in practice than expected - and I've never used them personally. The Green Celestions have an xmax of 4mm. As this is a proper voice coil overhang it's probably equivalent to 6.5mm on an Eminence and is perfectly acceptable, although not in the same league as the Beyma it must be said.

Even with collection only, it will go for more than £100. I had one and I still have the back pains. I don't know if they're all like that, but man was it heavy.

[quote name='bertbass' timestamp='1360862868' post='1977619'] One of these [url="http://www.behringer.com/EN/Products/BEQ700.aspx"]http://www.behringer...cts/BEQ700.aspx[/url] or one of these [url="http://www.behringer.com/EN/Products/PB100.aspx"]http://www.behringer...ucts/PB100.aspx[/url] should do the trick. Got one of each and clean boost is what you'll get and pretty cheap too. [/quote] I can recommend the PB100. Cheap but great quality - quiet, totally transparent and enough juice to drive a power amp if you want to. You get volume, bass and treble thrown in. Why pay more?

[quote name='Phil Starr' timestamp='1360580306' post='1972501'] The Beta has been redesigned recently. Q is ).46 which my table says means box size is Vas/1.03 or 120l which is big but practicable. The bass peak is 1dB which you will just notice. The cut of frequency is fs/0.97 or 46Hz which is OK too. Put it in a smaller box and you will get a bigger bass hump and cut off will rise a little but this speaker works for me. [/quote] Another important criterion when choosing a driver for bass guitar is its frequency response. Good bass guitar drivers have a frequency response that extends smoothly up to and beyond 2 or 3kHz. This makes a difference to the clarity of "tone", even though the driver rolls off much earlier than this off axis. You should avoid drivers that have large peaks in the frequency response because this is a result of undamped resonances and distortion - although not usually a problem if you are going to cross over to a midrange driver and less of a problem if you use a smaller driver on top. The Beta 12 is the only 12-incher in the Eminence range of ceramic drivers that has a decent frequency response in the midrange (as far as I know). I fitted one to a PA speaker last week and put my bass through it. It sounded all right (the JBL compression driver helped but the plastic cabinet didn't). It was in a 45-litre cab and I didn't measure any bass hump at all. I'm surprised that the Celestion bass guitar range gets so little attention on here - especially as these are specifically designed for bass guitar. I've used the 300-watt green neos and they were good. The ceramic BL12-200X is under £50 and would be my first choice for a budget bass guitar 12-inch driver. Phil's Beyma certainly looks the business though.

Beyma changed the spec of that driver in 2006. It looks like the only thing they did was to fit a stiffer suspension: the coil and cone look the same. There will some difference around the bottom rolloff point, but not much. Phil's spec is the current one.

[quote name='Mr. Foxen' timestamp='1360607407' post='1973296'] Polarity flip one result and overlay them, then you can isolate the difference part. That's always interesting. [/quote] You could use this: http://www.libinst.com/Audio%20DiffMaker.htm

The Faital will probably be a tad bigger than the Ashdown driver because it's a cast chassis. You can always widen the existing hole with a jigsaw but the best way of doing it is to get a piece of 1/2" MDF from B&Q and cut a spacer. I think there is somebody on eBay selling MDF spacers (for the car audio guys) if you don't want to go to the trouble. Come back and tell us what you think. I'd be surprised if you are anything less than amazed at the difference

I wouldn't use a Kappa as a standalone speaker personally - it's got a huge peak in the upper mids and doesn't really go high enough. It's an LF driver (unlike the Kappalite, which is fine but pricey). Grab yourself one of these if you can stretch to it: http://basschat.co.uk/topic/197764-faital-pr400-15-bass-driver-for-sale-x-2/. Not only is it neo (so it's light) but the price is half what you would normally pay in the shops - so you wouldn't lose any money if you eventually decided to sell it. Also, it is in a different league to the drivers you have been considering so far and will work fine in the Ashdown.

Actually, I believe Bergantino produce the thing you are looking for - and it's highly rated too. But it has been designed specifically for bass instruments.

It beats me:-)

Thin-wall cabinets ring like crazy. Plastic cabs are useless for bass. Plus a good PA cab is voiced a lot flatter than a bass cab. This is not a good idea.

If you want something that will work and not blow up, the Eminence 15 Beta will do that. As far as matching the cab is concerned, it doesn't really, but neither does the original Ashdown driver. My guess is that it will sound worse than the original Ashdown driver because it's been built down to a price for people who want cheap, cheap. (Hint - it's a pile of sh*t!). You could probably get something much better on the secondhand market if you can watch and wait.

[quote name='JTUK' timestamp='1359669257' post='1958677'] A decent 410 shouldn't be boomy, IME... but an amp with a semi paramtric EQ stage is good for notching problematic rooms... [/quote] This is your answer. Without knowing where the boom is coming from and what frequency is causing it you are working in the dark. A separate parametric equalizer is your best bet. It will also enable you to sort your midrange problem out.

I'd just like to air my appreciation for one of Basschat's real gentlemen. Tom replied to my request on the forum for help to pick up an equalizer I'd bought from someone in east London. Despite the snow, Tom travelled from Essex to Leytonstone to pick the unit up for me. Not only that, but he paid him the cash on my behalf that I'd previously transferred to his bank. To top it all, Tom was brilliant and packed the unit up for me (the seller had promised to pack it up but failed to do so). What can I say? My faith in humanity is restored:-). Seriously, Tom is a very generous guy and, if you're reading this thread to see whether you can do business with him, then the answer is a definite 'absolutely'.

Good advice from Phil as usual. You could use a spacer ring to fit your new driver. Cut it out of 1/2" MDF to suit the new speaker. For a reversible job, put adhesive foam on the back, screw it to the front of the cab and then bolt your driver to it. Your new speaker will be 1/2" closer to the grille but there's usually enough space to allow it. This is a common problem when going from a pressed steel to a cast chassis. I did this with an Ashdown cab and it worked fine.

What about singers who think their only obligation is to bring a mic and are happy to let the others in the band buy the PA? How common is that or have we just been unlucky?

Richard, I certainly hope you can persuade your customers to post their build experiences here. There are probably quite a few prospective punters watching and waiting.

Has anyone on here bought one of these kits yet?

A bit late (sorreee!) but Mike bought an amp from me a few months ago. It was a perfect transaction and Mike is a great bloke to do business with. Do not hesitate!

I've bought an equalizer from a very nice bloke in Leytonstone E11 and I've no way of getting it over to Dorset. I thought I'd be able to send a carrier in to collect it but he says he can't promise to be in all day and is not interested in dealing with freight companies. Is there anyone in London E11 who would be able to collect (it's not heavy) and then hand it over to a UPS driver for me? There would be a bottle of Scotch or a nice bottle of wine in it for you.