alexclaber

It's a bit late now! I suspect those of you that enjoy carpeting also enjoying wallpapering. I don't. But I am very happy to fuss endless over getting stupidly thin pieces of ply to line up neatly and then fill and sand any imperfections until it all looks very pro. Btw, that's the 3015 not the 3015LF. The LF sounds nice on its own but too treble-shy for most. The 3015 is very punchy and clear - seems very low distortion compared to the usual 10" cabs. Alex

3/4" MDF is not the way to go for light weight! 1/2" ply plus bracing is much better. Interesting specs on that Fane - I think the quoted Xmax must be Xlim, otherwise that driver is impossibly good (you can't get sensitivity, Xmax and Qts all that high at once). Alex

[quote name='david_l_perry' post='222657' date='Jun 20 2008, 09:16 AM']On the next one...[/quote] Am not doing carpet again - I spent so long getting the woodwork nice that it's almost a waste to cover it up with furry stuff. Tuffcab paint on all future ones! Shall try the WD40 tip later... Alex

Last night I finished the first of my lightweight cabs - this is a one-off for Mr Russ but it uses the same speakers and construction as my other designs, just different box proportions to match his Markbass 2x10". Unfortunately I don't have a set of scales - hopefully Russ does, so we can find out quite how light it is! [url="http://basschat.co.uk/index.php?showtopic=13344&view=findpost&p=222449"]http://basschat.co.uk/index.php?showtopic=...st&p=222449[/url] Alex

Voila!

Done! Photos to follow... Alex

Hmmm, carpet done. Not a fun job... Just recovering before I put the speaker, grill, handles and jack back in. Alex

[quote name='Crazykiwi' post='222082' date='Jun 19 2008, 12:58 PM']I don't understand it, I mean, do they teach ARSE 101 at soundman school or something?[/quote] Well they certainly don't teach much sound engineering... (A few honourable exceptions recently, thankfully!) Alex

A lot of older music that is mistaken for ska is actually rocksteady. Ska is faster with the bass usually walking 4 notes per bar, rocksteady is somewhat slower with the bass playing syncopated 8th note based patterns, reggae much slower. Jackie Jackson was the bassist first noted for 'doubling up' (playing 8ths, not 1/4s and thus forcing the music to be slowed down). Wikipedia is quite accurate on all this kind of stuff: [url="http://en.wikipedia.org/wiki/Ska"]http://en.wikipedia.org/wiki/Ska[/url] Your average man on the street would identify ska as uptempo music with the guitar on the offbeat and thus we in my band claim we're BritSkunk (Anglo Ska Funk) because of this key feature, even if little else is authentic. Alex

[quote name='rodl2005' post='220335' date='Jun 17 2008, 02:20 AM']I "Cope" with all the weight by using a trolley!!! Makes loads EZ as!!!![/quote] This probably works well in Australia, as in the US. Unfortunately in the UK we are plagued with old buildings and thus staircases when it comes to moving gear. Wheels and stairs don't mix! Alex

Oh yes, and the most important chops for a bass player are the ones everyone takes for granted yet are often so bad at - tone, timing and taste. To hell with playing fancy twiddly stuff, drive the bus first. Alex

What worries me is the unwritten assumption that everyone is nailing these grooves in covers bands - based on the ones I've heard the reality is horribly different. To the original poster - are you really making these songs happen or are you just playing the notes? Be honest with yourself. Alex

Amidst the carpeting joy, fun, fun, fun... Ordered the parts for my new crossover design for The Big One. Also ordered some parts to make a 200Hz highpass filter for my 6ND410 so I can put it in a tiny cab as a monitor for gigs with zero monitoring supplied. Alex

I rarely play covers but in my absence my bandmates decided that we're going to add a couple to the set - Hit Me With Your Rhythm Stick and If You Want Me To Stay. No complaints from this bassist! Going to be fun having to play and sing them... Alex

[quote name='lowhand_mike' post='221484' date='Jun 18 2008, 04:07 PM']if you are listening to tap dancing through a bass rig it may be time to go to rehab. [/quote] No, no, no. Alex

[quote name='lowhand_mike' post='221453' date='Jun 18 2008, 03:37 PM']interesting to see how early good results were formed and that this far down the line things haven't changed in instrument cabs (well some people are pushing it)[/quote] Look how many people spend all that money on an iPod and then proceed to listen to it through the original headphones - if only they knew how much better it could sound! To a large degree it's the same with cabs. Alex

Aha! "This entire thing goes back to the Eleanor Powell "double tap" incident at MGM studios in the early 1930s. When monitoring playback of Powell tapdancing an echo was noticed on the taps. John Hilliard, subsequently the greatest of all horn designers, was a young sound engineer at MGM and traced the problem to the 8 foot difference in the path lengths of the horns in the 2-way Western Electric monitor speaker. Hilliard did experiments that showed that the effect was time and frequency dependent and that a delay of less than 3 milleseconds (about 3 feet) was inaudible using crossvers between 350 to 800hz. A result of this incident and WE's refusal to market their improved Fletcher loudspeaker was the decision of MGM sound honcho Douglas Shearer for MGM to design their own improved system which would among other things minmize time delay. Hilliard was put in charge of the project which then developed the famous Shearer Horn. An entire galaxy of talent worked on this system including Hilliard, James Lansing, Bob Stephens and even RCA's Harry Olson. Note that though the folded basshorn of the Shearer cut time delay compared to the WE snail horns it didn't eliminate it totally but Hilliard's later Altec Voice of the Theatre did. So it seems that even though Hilliard thought some delay was inaudible the existence of any at all still nagged at him." Alex

[quote name='rodl2005' post='221151' date='Jun 18 2008, 09:49 AM']Thanx again Alex. AGAIN U help clarify many points I find difficult to grasp!!!! Thanx![/quote] Nice to be of use! Alex

[quote name='stevie' post='221376' date='Jun 18 2008, 01:47 PM']Indeed it is a short list - more's the pity. I certainly think a midrange driver is of more value than a tweeter for bass.[/quote] I agree, that's why my new cabs use a midrange speaker rather than a tweeter. I'm leaving the tweeter as an extra cost option because some people just can't live without that tone but I think they're relatively few and far between. It has been really hard to design a good crossover and the parts cost is far in excess of that of a typical tweeter, which explains why they're quite rare. [quote name='stevie' post='221376' date='Jun 18 2008, 01:47 PM']Use good science, of course. The problem is knowing what is good and what is bogus. Or perhaps more aptly, what is important and what isn't.[/quote] IME the bogus information is usually heard within close proximity of any guitar shop! Alex

Something I've noticed from modelling drivers in WinISD Pro is that the phase difference between models is rarely so huge as to cause cancellation if the cab tuning frequency is the same. Here is an SPL phase plot for a ported home cinema subwoofer: The point at where the phase flips from positive to negative is the port tuning frequency. In a typical bass cab expect this to be shifted up to 40-55Hz. If two speakers are 180deg out of phase you'll get full cancellation. If they are 0deg, 360deg, etc out of phase you'll get full reinforcement. Anywhere in between and you get anything between some reinforcement and some cancellation. The thing about adding a lowpass or highpass filter to one of your cabs is that you're likely to run into more problems with phase response as the filter won't work as predicted by the resistance model due to the impedance varying hugely in the low frequencies. I would recommend adding a highpass filter to a cab that keeps farting out but I'd be wary of doing any more than that. If you want to crossover cabs at low frequencies you're better off going with an active crossover and a dual channel amp. Alex

Sanded the rest of the cab down yesterday, it's looking nice and professional. Will give it a quick once over at lunch time with a finer grit, then a bit of filler plus primer on the baffle and I'll get it sprayed later. And assuming that dries quickly enough, carpeting joy later... Alex

[quote name='stevie' post='221237' date='Jun 18 2008, 11:11 AM']Shouldn't that be placing drivers horizontally without crossing over to a midrange unit? Leo Fender and Jim Marshall didn't make sde-by-side bass cabs in the 1950s. Marshall bass cabs were 4 x 12, 1 x 15 and 1 x 18 and Fender had the Bassman, which was a 1 x 15. The side-by-side 2 x 12s these companies built were guitar amps. The Fender Twin and the Marshall Bluesbreaker (and the Vox AC30 before it) used open back cabinets based on a perfectly valid dipole design that still enjoys popularity today.[/quote] How many bass cabs do you see with midrange drivers? It's a very short list... A 4x12" is a side-by-side design. 2x12" guitar amps, whether open-backed or not, consistently work better if you turn them on their side - it gets the speakers closer to ear level and significantly improves off-axis response. If you can persuade your guitarist to do this it can do wonders for the sound of your band, I know my guitarist is a total convert. Personally I don't have a problem with people doing whatever they like to get the sound they want - but surprisingly often their decisions are based on faux science and witchcraft rather than the claim of just using their ears! If you are going to use science to aid your decisions, use good science! Alex

[quote name='bass_ferret' post='221188' date='Jun 18 2008, 10:20 AM']The reason all those studio monitors were OK was because they were 3 way designs so the horizontal alignment would not cause problems because the cabs would have crossed over to the midrange drivers at the frequencies where comb filtering becomes a problem.[/quote] Same with the Acme Low-B4 - the woofers crossover to the midrange @ 1kHz. The tweeter and mid are side-by-side because that's where they fit and Andy deemed it more useful to have them high up vertically aligned, but you can always turn the cab on its side if you're elevating it. Alex

[quote name='Galilee' post='220742' date='Jun 17 2008, 04:48 PM']I did a cod-psychological test once that showed that I was (pretty much) 100% using my ‘left brain’ all the time. So I’m great at analytical, logical, mathematical stuff, but rubbish at imagistic, intuitive, creative stuff.[/quote] Bach's music is incredibly logical and mathematical and he was probably the most significant composer of all time. I know for me the initial ideas come out of nowhere but tying them all together into a composition feels like a mathematical puzzle at times... Alex

[quote name='stevie' post='220827' date='Jun 17 2008, 06:42 PM']By 'placing drivers horizontally', I assume you mean like this:[attachment=9729:SCM200ASL_Pro.JPG][/quote] Nice try but no cigar! Alex