gusthebass

Ta! Just to say the Buzz/vibration happening at louder levels on the lower G note were due to the speaker unit itself. It vibrated where the magnet met the pressed steel chassis. Someone had tried to sort it by stuffing matches into the gap, but only when I swopped it for a Deltalite 12 I had lying around (..in an active monitor I'd repaired!) that the buzz was cured. And it's now 2KG lighter... result! I repaired the old speaker by running hot glue all around the join - seems to be OK in it's new home in the monitor, so all's well!

Mind you, there is no way this is a transmission line. the line itself has to have the cross sectional area of the cone at the speaker end to avoid pressure changes and as Bill says is 1/4 wavelength so that's 6 cu ft packed inside a 2 cu ft box. Truly amazing! So my somewhat different take on the TL idea was to have almost a 1/2 wave line at the lower freqs (where the cab. would naturally be dropping off..), so the air from the back of the speaker arrives at the front large port (via the pipe) in phase with the air at the front of the speaker - hence 1 speaker for free! There are a load of compromises involved, and yes I know how long a lower E, never mind B is, but with wadding you can slow the speed of sound (and reduce efficiency).. and err.. well it didn't really work. Oh well.. I needed a bigger pipe than i used for starters (I had about 1/3-1/2 speaker cone Surface area).. and and and. Too heavy as well with all the wood making up this heavily folded pipe. Now if someone out there is into large Carbon Fibre Composite complex shape moulding and owns a big autoclave.. come on, wood is SO passé these days...

[quote name='dan670844' post='1218997' date='May 3 2011, 07:54 PM']Hey Gus greetings from England, would be interesting if you could tell us about all those boutique cab builders in Germany, would be nice to hear from a players perspective. Thanks Dan[/quote] In no particular order or preference Flying Music Circus [url="http://fmc-audio.jimdo.com/"]http://fmc-audio.jimdo.com/[/url] , BassSyteme [url="http://www.basssysteme.de/index.htm"]http://www.basssysteme.de/index.htm[/url] BassTown, [url="http://basstown.de/"]http://basstown.de/[/url] and HOS - "House of Speakers" that seem to have lost the website, but you can get them at Musik Schmidt at least [url="http://www.musik-schmidt.de/de/Baesse/Bassverstaerker/Bass-Boxen"]http://www.musik-schmidt.de/de/Baesse/Bass...rker/Bass-Boxen[/url] They are quite into "Tandem" speakers.. There must be others out there, as I said 've got a BassSyteme 15, but I've heard good things about the others I mentioned too. All these sell direct, I don't know how their English is, but they're all happy to chat and advise on the 'phone iMO. 40KG 8x10s... humm!! Or 33KG 6x10?'?!! If we want to get into a NEO/Ferrite discussion.. Oh yes, and "Bass Cabinet" in German is "BassBox(en)" - who'd have thought it! Cheers,

[quote name='Bill Fitzmaurice' post='1218817' date='May 3 2011, 05:48 PM']+1. Long excursion drivers aren't higher in sensitivity than shorter excursion drivers; if anything they're less sensitive, as is the case with the 3015LF. The advantage to them is being able to utilize higher power amps. If you have a lower power amp they won't do you a bit of good, and you're better off using multiple less expensive cabs than one more expensive cab. The other advantage to high xmax drivers of the Kappalite mold is that they're state of the art with all of their specs, which means they work better in smaller cabs than most older driver models.[/quote] So indeed, my experience. And the question then becomes how much more power does your amp actually need to really become "louder" (Higher SPL) with a small new cab instead of a big oldie!? Then there's this other thing about total membrane area (the 8x10s thing!)- though that could just be due to the increased number of drivers increasing the SPL for the same amp settings.. I'd liken this to playing acoustic bass guitars vs. a double bass - you know one of these works and the other one simply doesn't. Body volume, surface area..? Carry on please!

I've been looking through the forums here but haven't really found the info I'm after. I know watts are getting cheaper (and lighter!) all the time, but I'm thinking an efficient cab is rarely discussed, but makes a big difference. IMO I need less "loudness" when I've played with an 8x10 than with a 2x10 or a 1x15. I can hear myself better across the stage, and yet I seem not to be as "loud" as with a 2x10 Combo I regularly use - hey, even the keyboarder complained less! This could be due simply to the height of the speaker - nearer to my ear height so I turn it down - but I think that it's a lot to do with membrane area.. .. please don't bite too hard at that! And that 2x10 Combo is normally kickedback to point at my head- an HK Quantam. And along the lines of efficiency I've got 2 1x15s, one old 200W RMS from the 70s/80s, a large box, big front port, EV speaker, made by Craaft - and another modern (basssysteme.de) one that's really small (just larger than the speaker + tweeter), nice and light, also ported and 600W RMS(!yes!). BUT when I use the same amp into these, the big old beast is much louder at the same amp settings - and (as ever, you have to use my ears!) IMO a much better "Bassier" sound - which is why I play the bass in the first place. 'Course you can fiddle with the EQ and wind the amp up more, but I think it shouldn't be necesary to have to do that. I even made a 2 x10 cab with a transmission line system, so a bit over 2M of folded port to get my low freq. levels up.. but didn't really work. I know horns would have to be immense to help us bassers, so that's also out, unless you know different! So come on you brains out there - thoughts please. And if you're wondering, why?, I'm thinking a lot about getting a lightweight 8x10 (40KG) because of this - there's several speaker outfits over here in Germany all with pretty fanatical followings that seem to make good and lightweight kit- but really I'm meant to want to go small & light - so the industry seems to assure me.. never mind the family! Thanks in advance, I'm looking forward to a good discussion here - how about a list of sensitivity dB/Watt/1M specs for different speaker layouts & designs, but at a bass applicable 50 Hz or so and not the normally quoted 1KHz?