alexclaber

[quote name='gilmour' post='140409' date='Feb 14 2008, 04:02 PM']Alex is probably right we may well see more 15's now they can be made so light.[/quote] I'm still in shock at how incredibly light an Kappalite 3015LF is out of the box! The height thing makes even more of a difference with 15" speakers as if you don't have a separate midrange speaker the upper midrange output becomes very directional, so although a 15" cab might be making a great sound if you put your head on the floor it won't be so clear when you're vertical. My DIY cab will have the bottom of the 15" about 10" off the ground and then the 6" mid above the 15" (offset to minimise baffle step issues). Alex

See, I told you you'd be better off with 15"s! That 2x15" is about 2" bigger in each direction than the 15"+6" I'm building - nice and manageable to move but tall enough that your ears rather than your knees end up listening to it. The weight difference between an expensive old cast frame 15" with big magnet and an equivalent quality neo one is massive - I wonder if we'll see more people using 15"s now that 2x15" cabs can weigh less than a 4x10"? Alex

[quote name='bass_ferret' post='139080' date='Feb 12 2008, 08:49 PM']Thomman are in the former GDR, as are Warwick.[/quote] Warwick are? They must have moved: My '87 Streamer amusingly says "Made in West Germany" on the back. A lot's changed in 20 years! Alex

[quote name='mhuk' post='139777' date='Feb 13 2008, 06:45 PM']You must be buying from a different supplier - from Blue Aran handles (medium=450g, large=575g) are about £4 and corners 50p (25g).[/quote] I should have said casters and handles can be expensive and heavy - the large diameter casters and steel handles weigh a ton. But yes, I did get the lightweight cheap plastic handles from Blue Aran! Alex

[quote name='dood' post='139595' date='Feb 13 2008, 03:55 PM']I'm already interested in seeing how a non biamped version would work out.[/quote] Me too, think it would be a very nice match with one of the higher power lightweight heads on the market. I'm actually intending to use a passive line level crossover, which will be a split lead with a small box in the middle, so if you have two amp channels you can put this between preamp and power amp and you get a 2nd order highpass and 1st order lowpass, with sufficient attentuation on the highpass to match the sensitivities. [quote name='dood' post='139595' date='Feb 13 2008, 03:55 PM']Another interesting find: Powersoft, (I own one of their poweramps) I see actually make 2 way biamp modules that can be added to a cabinet to make it active too! The treble and bass signals are treated actively (as opposed to just having a single amp and passive crossover.)[/quote] There's quite a lot of active modules on the market - unfortunately they all cost rather a lot - and I already own a very nice power amp. [quote name='dood' post='139595' date='Feb 13 2008, 03:55 PM']Whats the projected costs involved Alex?[/quote] This is where it gets challenging. Things to bear in mind with cab building: 1. Good plywood is quite expensive. 2. Crossover components are expensive. 3. Metal grills are expensive - and heavy! 4. Casters, handles and corners are expensive - and potentially heavy. 5. Finishing - paint/carpet/tolex - none is easy to do well, all cost money. So in light of all that I've decided to go for very thin birch ply - cheaper and lighter but requires much more bracing - plastic handles, no corners, no casters, paint finish, fabric grill and the aforementioned biamping with PLLXO. The 3015LF is great value, about £100. The midrange is certainly good value because it is incredibly high output and low distortion, sufficiently so to keep up with a pair of 15"s being hit by high wattage - unfortunately it is rather expensive and actually costs more than the woofer! Other components have been pretty cheap. I'm enjoying the challenge of trying to build the best possible cab for as little money as possible - much more fun than just throwing money at it. Alex

I have a simple 4-way block in my rack and have cut down the leads on my preamp and power amp to tidy up the cabling. The block has about 30' of 13A cable on it to minimise the pain in stupidly wired (all?) venues... Alex

A box of fun containing connectors, leads, grill cloth and the most spectacularly light 15" woofer I have ever held, has arrived! Honestly, I thought the box was empty before I saw all 15" of bass awesomeness staring back at me... Alex

Not quite the grease of the real thang but the whole band is more hyped up. Amazing how many drummers seem incapable of keeping time without ticking away on their ride or hihat - everyone should learn some linear drum grooves. Good stuff! Alex

Zigaboo! Anyone tried any of his beats? Alex

[quote name='Merton' post='138879' date='Feb 12 2008, 02:37 PM']Cool, looking forward to watching this develop, you've been talking about it for a while![/quote] Yeah, I've been through so many different designs so I wanted to make sure I didn't think of anything better before I committed to the build! [quote name='bremen' post='138884' date='Feb 12 2008, 02:39 PM']What else will you do? 9mm is pretty bold, but for sure a well-braced 9mm cabinet will be better than an 18mm poorly braced one. Hope it goes well![/quote] I'm going to divide all the panels with strips of ply set at right angles but before glueing them in I'm going to prestress the cab with 2"x2" and wedges so the panels and bracing are tensioning each other. The port is going to be a large triangular port which will brace part of the cab and the mid enclosure is going to be a wedge shape that braces another part. All the joints will be butt joints with 18x18mm wood running along the inside edges to increase the glued surface and add further strength. I'm quite new to woodwork so need to keep it relatively simple, though longwinded... Alex

[quote name='Happy Jack' post='138898' date='Feb 12 2008, 02:48 PM']I understand that the cone's bi-directional movement comes into the equation, but I'm guessing that the Vd effect is actually relatively small ... an 18" cone will be easier to vibrate than a 10" cone, but a 10" cone will weigh less and therefore respond faster. So Vd will certainly make a difference, but as a factor it will be massively outweighed by simple size.[/quote] No, Vd matters more than anything when it comes to moving air at low frequencies. The best way to understand all this is to read this: [url="http://www.eminence.com/resources/data.asp"]http://www.eminence.com/resources/data.asp[/url] Download this: [url="http://www.linearteam.dk/default.aspx?pageid=winisdpro"]http://www.linearteam.dk/default.aspx?pageid=winisdpro[/url] And then start running simulations of different speakers - some typical bass cab choices are the Eminence Alpha 10 (for sealed cabs), Beta 10 (ported cabs), DeltaLite 2510-II (modern neo ported cabs). When you're dealing with low frequencies even the heaviest cone can move fast enough. Once you get into the midrange a lack of acceleration can manifest itself as a reduction in sensitivity but by then you're often running into voice coil inductance reducing response as well. Considering how most bass guitar 18" cabs are rather undersized and use relatively cheap (and thus low Xmax) woofers, I wouldn't be surprised if Ampeg are correct regarding their 410HLF. Alex

[quote name='BOD2' post='138789' date='Feb 12 2008, 12:29 PM']1. Speakers are not flat circles they're cones so its a volume calculation not an area calculation you'd need[/quote] It's the swept area that matters, so it's still a circle. Though you do need to bear in mind that the 10", 12" or 15" diameter is nominal and the real diameter once frame and surround have been subtracted is significantly less. Alex

[quote name='bass_ferret' post='138797' date='Feb 12 2008, 12:42 PM']Should have compared it to the old Cerwin Vega earthquake drivers that had 2 inches of XMax[/quote] If that is correct I'll eat my hat. 0.2" of Xmax would be pretty damn good for an old 18" woofer. Alex

I only found this station last week when the guy doing our bathroom put it on... Alex

Finally bitten the bullet and ordered the parts for this cab. Basically it's an Eminence 3015LF woofer in a ~110 litre ported box tuned to 46Hz with a sealed sub-enclosure containing an Eighteen Sound 6ND410 midrange. Am still hunting down some suitable plywood - looking for high quality 9mm baltic birch with equal thickness plies throughout. Will be doing all manner of strange bracing to get sufficient stiffness from such thin ply. External dimensions will be ~ 32" high x 20" wide x 16.5" deep - a neat fit in the boot of my car along with my 4U shallow rack. Estimated weight <50lbs. Alex

A couple of rehearsals ago whilst my bandmates were outside smoking I found myself attempting the one man band thing - left hand playing bass, right hand and both feet playing drums. Even worse than playing bass and singing simultaneously! Interesting challenge though... Alex

[quote name='Happy Jack' post='138779' date='Feb 12 2008, 12:16 PM']What am I missing here?[/quote] The third dimension! The amount of lows a speaker can produce is indeed dependant on the amount of air it can move but that depends not just on speaker area but also how far back and forth the speaker can move. In speaker specs this is called Vd, which is the produce of Sd (surface area) and Xmax (max linear cone excursion). For every octave you descend the speaker has to move four times as far to produce the same SPL. The only exception to this is with ported cabs where the port assists with output as you approach the tuning frequency, which is why the only sealed bass cabs on the market tend to have lots of speaker area to achieve high LF SPL with a port helping out. This then relates back to real world power handling - if speaker A can move twice as far as speaker B, then it can handle four times as much power and produce 6dB more output in the lows. Alex

[quote name='Cantdosleepy' post='138769' date='Feb 12 2008, 11:52 AM']If you never practice on the bass because you are so busy playing every other instrument, obviously your chops will suffer.[/quote] Though the chops that matter when playing 99% of basslines are nothing to do with speed and everything to do with tone, timing and dynamics. Alex

Sufficient gauge (usually less than you think you need), good connectors, solid construction and decent shielding are all worth paying for. Lower capacitance too with passive basses. Everything else is so close to snake oil that you might as well spend the extra money on hypnotism to help you believe your rig sounds better than ever. The human ear is a contrary and very subjective piece of kit! Alex

[quote name='Josh' post='138356' date='Feb 11 2008, 05:55 PM']Not as such, but it depends really, I've seen and taught guys who have their bass at different heights, I'm happy to listen and watch if their technique is clean and practiced but if it's bad technique and what-not I tend to loose interest.[/quote] See now my view is that if it sounds good and it isn't doing you medical damage, then play the instrument however you care. Geezer never sounds clean and practised - in fact nor does Bill Ward - but that's what makes the music sound so great! Back to the topic-ish, has anyone else noticed how ridiculously awesome Matt Cameron is (particularly on Soundgarden - Superunknown)? His timing is incredible! Alex

[quote name='Josh' post='138343' date='Feb 11 2008, 05:36 PM']Bad thing is it's gone a tad bit too far on me, by which I mean, if I hear a great drummer, perfect sound, great fills, the lot and then I see them live and his set-up is all off and his technique is shoddy, I just can't accept to liking them.[/quote] ????? Do you have the same view on bassists whose strap height preference is different to yours? Alex

Nice work! Alex

[quote name='ped' post='137570' date='Feb 10 2008, 01:25 PM']Alex, I got the 210 because it was really cheap. I thought it sounded great - maybe it doesn't on paper, but where it matters it sounded really full and rich.[/quote] Cheap is always good! Regarding the sound it's like using a Lotus Elise vs an AMG CL to achieve a certain lap time - both will probably get round the track in a similar time and both be good fun doing so, but one is an elegant and efficient solution whilst the other is impressive on paper but a messy combination of huge power vs huge weight. Alex

[quote name='bassman2790' post='137631' date='Feb 10 2008, 03:44 PM']The Low-B4 or B4W would seem to be just what I'm looking for. Is there a distributor in the UK or would I have to import one?[/quote] No UK distributor but very straight forward buying direct, just figure 1.9 USD to GBP and then add about 25% to the cost (including shipping) to account for import duties. The small extra cost of the B4 over the B4W gets you a really nice mid and tweeter with an excellent crossover and protection circuitry and if you want to use it with another cab just to add bottom, simply turn the attenuators down. 99% of the time I suspect that one cab on its own will be enough, they are LOUD! Alex

[quote name='bassman2790' post='137518' date='Feb 10 2008, 11:35 AM']That's really useful information Alex, thanks. The question is how do I solve the problem? Judging by the information you've kindly supplied, if I had a cab where the roll-off didn't start until about 50-60Hz, I should notice a difference in the 2nd harmonic. Is there anywhere where I can find the specs of mass produced cabs? Or a guide to how I could make a 1x15 cabinet that performed well down to 50Hz?[/quote] The aforementioned Acmes do a fine job of output down to 31Hz at the expense of sensitivity. As you have plenty of power that would be a great route for you - a single Low-B4 would be a righteous rig with 1500W from your Laney into it. Alternatively a pair of Low-B2s for a modular solution. Alternatively a higher sensitivity route that gives up the frequency extremes but produces good output from 40-6000Hz would be the 3015LF/6ND410 cab I'm building. Once I've done one for me I'm going to work out a passive crossover version but as you can biamp it my existing design would work great with your B1. The trade-off is that as you're biamping into an 8 ohm load instead of bridging into a 4 ohm load your amp produces ~6dB less power so the sensitivity gain by losing the last half octave of response doesn't actually get you any more max SPL. Add a second cab with another woofer and you do gain an advantage. The Dr Bass cabs that Robbie's importing are available with the 3015LF but make sure they have sufficient internal volume - any less than 100 litres once port, bracing and drivers have been subtracted and you're hamstringing yourself. Personally I'm not keen on the Basson approach, they strike me as designed by the marketing department, not engineers - heavy magnets, low port tuning and stupidly heavy cabinets looks impressive on paper but gives mediocre bass response where you really need it, though extension is certainly deep - lots of rumble but not a lot of fullness - and what is the point of a 2x10" that's as big and heavy as a well designed 4x10"? Alex