Bill Fitzmaurice

[quote name='xgsjx' post='199083' date='May 14 2008, 04:41 PM']Should I keep in with the matching rig & go for something MB, or should I try maybe an Ampeg 410 or SWR 1x15. Cheers.[/quote] The right way to do it is to add another identical cab, and in use stack them so that the woofers are vertically aligned. From an audio engineering standpoint one should never mix different drivers operating within the same frequency bandwidth. This does of course go against what's accepted practice by both the bassplaying and cab manufacturing communities, but bassplayers by and large are not audio engineers, and manufacturers build to suit demand, not correct audio practice.

[quote name='gilmour' post='198755' date='May 14 2008, 09:36 AM']Go for an Omni Top 15 ... my omni 15TB is plenty plenty loud enough.[/quote] These are very different cabs. The O15 is designed to run with high sensitivity flat to 50 Hz, for a full bottom end well beyond what commercial cabs are capable of. The OTop 15 has even higher sensitivity but is flat to only 100 Hz, giving a vintage style tone but with a much higher output than vintage cabs.

[quote name='umph' post='197857' date='May 13 2008, 07:01 AM']Was thinking of going for a 2X15 that i'd be able to wire in stereo so would be able to choose between using one speaker for home or two for louder gigs[/quote] Not a practical notion IMO. Two 1x15s, much more so.

[quote name='mintybassman' post='194978' date='May 8 2008, 02:43 PM']Ah cross-over. Now we're talking... Would changing my EQ on my amp effect this? i.e. push the signals too high etc? Am i buying one or making one? Or am i naive to the humungous complexity of that task? What kind fo prices am i looking at for one? This is new territory for me.[/quote] Making is your best option. It's a simple circuit, only two parts, put them in a box with an input jack to go to the amp, outputs to each cab. Figure $50, a lot cheaper than new cabs. Finding the parts on your side of the pond is the most difficult part, very odd since the #1 source, Jantzen, is Danish.

A first order crossover at 150 Hz would route the lows to the 15, the highs to the 2x10, and keep the overall load at 4 ohms. Get component values at [url="http://www.lalena.com/Audio/FAQ/XOver/"]http://www.lalena.com/Audio/FAQ/XOver/[/url]

[quote name='stevie' post='187150' date='Apr 28 2008, 06:51 AM']Er, no... this is incorrect and quite misleading, not to mention confusing. The 6mm Xmax of the BP102 is a reasonable specification which will not lead to any loss of efficiency at bass frequencies. Higher excursions on a ten-inch driver might, but only because of a possible knock-on effect on cone area. Midrange efficiency is irrelevant for bass guitar amplification because there is always plenty to spare.[/quote]Tone is midrange. To get the extra xmax of the BP102 other T/S specs are also affected, resulting in a paltry 88dB sensitivity at 500 Hz. On it's own it sounds dull and lifeless, it needs to be used with a midrange driver to sound good. I don't recommend the BP102 for any of my full range speaker designs. OTOH, it does work very well in subs.

[quote name='mav' post='186324' date='Apr 27 2008, 05:15 AM']So two different opinions ? I was thinking if TE could push 500watts out of there 210 they would.[/quote]No musical instrument ten will take 250 watts broadband without exceeding xmax. The average is 50. [quote]Look for a driver with at least 5mm.[/quote] Very few tens go higher than 4mm, and those that do, like the BP102, have less sensitivity, so what you gain in one area you give back in the other.

[quote name='mav' post='181600' date='Apr 21 2008, 04:21 AM'], i'm thinking of replacing the speakers for something with more power handling like 300-400 watts 8 ohms.[/quote]The wattage rating of a driver has virtually no bearing on its output capability. That is determined by the drivers cone displacement, Vd, so unless you can find out what the Vd spec is for your current drivers there's no way of knowing what you need to replace them with to gain an improvement. [quote]As long as there a matching pair it doesn't matter?[/quote]The drivers must be matched to the cabinet volume and tuning frequency or they won't function properly.

Same answer as I gave you on TalkBass. The rules of physics are the same on both sides of the pond, so why ask exactly the same question on two forums?

[quote name='thinman' post='152701' date='Mar 6 2008, 04:14 PM']They look ace and it sounds like you're pleased with the sound. Just a point about the build: The plans suggest filling the cavities each side of the horn plates with pillow stuffing but I see you lined all the surfaces with the egg crate foam (which I was going to do anyway). Is yours OK without? I must admit I thought that by the time I'd lined all the surfaces there'd not be a lot of space to stuff. Shall I not bother?[/quote] I use pillow stuffing in the tight cavities where cutting small bits of foam would be time consuming, foam on the larger panels where it can be easily stapled in place. There's no functional difference.

[quote name='finnbass' post='170005' date='Apr 4 2008, 02:48 PM']I'm not really sure I'd want to be in the same room as a crowd of people who'd spontaneously applaud a DVD....[/quote]Not even Pamela and Tommy Lee?

[quote name='bremen' post='168910' date='Apr 3 2008, 05:25 AM']Which of us, if we had the cash, wouldn't want to do that to our basement![/quote]Not I. My 8 cu ft horn loaded sub provides all that I need and all that She Who Must Be Obeyed will tolerate

Lift the cab up by a couple of feet. That will eliminate boom frequencies in the midbass without killing the low end. Electronically a parametric EQ is best, as it can notch out the boom without killing the low end. Also be very cognizant of cab distance from the rear wall, adjusting that can also notch out boom frequencies. Pads are of very limited value, all they can do is filter vibration of the cabinet walls, and if your cab walls are vibrating you've got a whole 'nuther set of issues.

[quote name='david_l_perry' post='163537' date='Mar 26 2008, 02:39 AM']Neo drivers have been being used by Bass cab manufacturers and DIY bass cab manufacturers for a number of years.[/quote] Most notably by JBL in their PA cabs well over a decade ago, though JBL has never made them available other than in finished cabs.

[quote name='Jamesemt' post='159437' date='Mar 18 2008, 06:19 AM']Any ideas? The 'bug' was plugged into my Fender Precision, with the aerial resting on the bridge.[/quote] Fan cool the rack. If you haven't already ditched the aluminum front and side plates on the Superfly do so.

[quote name='Mottlefeeder' post='158766' date='Mar 17 2008, 03:23 AM']As we agreed last time you auditioned it in our church hall, the Omni 12 is very good as a full range PA cab. Whether its perceived weakensses as a bass guitar cab can be fixed with EQ (and amplifier headroom?) is something we have not really explored.[/quote] While the Delta 12 LF was about as good a true musical instrument woofer available when introduced, and is still better than most, it's not in the same league as the Kappalite 15 neos. Kappalite 12s are at least 10 months away. When they do come out I'm sure the 3012LF will become the recommended woofer for the O12, as it should offer much better performance whilst weighing half as much as the Delta 12 LF. Meanwhile round-wound players just need to roll off the mid EQ more than they're used to with most commercial cabs.

[quote name='bass_ferret' post='157025' date='Mar 13 2008, 05:13 PM']I remember you keep saying that Bill but can never remember why. Remind me.[/quote]Because the responses of the two cabs are different, and the result is akin to adding oil and water. If you want to use a fifteen to get maximum low end that's fine, and if you want to run a smaller driver to get better mids and high that's fine too. But the smaller driver shouldn't be a twelve or ten, it should be an eight or a six, and a crossover should be employed so that only the lows go to the 15, and only the mids and highs to the smaller driver. That's how it's been done in high-fidelity, theatrical and PA applications since circa 1927. Perhaps the electric bass cab industry will wake up and smell the coffee by 2027. Perhaps not.

[quote name='Paul_C' post='156949' date='Mar 13 2008, 02:32 PM']If you have (as I'm planning at the moment) two 8 ohm cabs, one a 1x12 250w, the other a 1x15 300w and you're running them from a single amp which is 500w @ 4ohms, will one cab dominate the other, or are they reasonably closely matched ?[/quote]What's more to the point is whether their responses will complement or detract from each other. The majority of the time the latter is the case. One of the first things you learn in How to Design Loudspeakers 101 is never to mix different drivers or cabs covering the same bandwidth. Yes, I know, that's how it's always been done with bass cabs, but that doesn't make it any less wrong. My advise: don't do that.

[quote name='bremen' post='155911' date='Mar 12 2008, 07:30 AM']indeed - at frequencies that low the room is as important as the box, so it's only outdoors that it's going to be practical to hear 32Hz.[/quote] Au contraire. The best results below 40Hz are indoors, in rooms where the longest dimension is less than 14 feet, as that's where cabin gain at a rate of 12dB/octave will result in high enough SPL to hear it. To understand why google 'Equal Loudness curves'. To hear a 25Hz tone at the same level as a 100 Hz tone at 100dB the 25hz tone would have to be 120dB, and getting 120dB at 25 Hz outdoors even with a very large horn-loaded sub woofer would require about 1,000 watts. I've tested many subs outdoors, and at 25Hz and 100dB if not for the reading of the meter one would not even know there was any sound present. To the OP, faggedaboutit, you don't need response to 28 Hz and couldn't use it even if you had it. [quote]Accugroove Bill Dickens[/quote] Not a bad choice, but does not perform as advertised. [url="http://billfitzmaurice.com/phpBB2/viewtopic.php?t=2362"]http://billfitzmaurice.com/phpBB2/viewtopic.php?t=2362[/url]

[quote name='warwickhunt' post='152115' date='Mar 5 2008, 06:48 PM']True we also have the singers nearly new 300 watt EV 1x12's (not sure of the model). Would there be any pro or con using either of these sets of mid/tops with a bin? I basically feel that the transient response of the EVs and there comparative newness will be of greater benefit than a pair of well gigged 15 year old 1x15s, right or wrong?[/quote]15s have poor midrange response and dispersion, as well as being quite large, and offer no advantages when used with a sub. OTOH if those EVs are of the plastic fantastic variety those old Peaveys may still prove better; there's only one way to find out. As for the sub capacity, generally speaking you need at least one sub per top to have adequate output. With high energy DJ mixes a four to one sub to top ratio isn't unusual.

[quote name='warwickhunt' post='151345' date='Mar 4 2008, 04:15 PM']we'd be struggling with phase cancellation with two as we'd not get them far enough apart[/quote]Simple cure: put them together.

[quote name='Merton' post='151559' date='Mar 5 2008, 05:12 AM']I didn't say it made a difference to the sound, it makes a difference to the amount of power going down the first lead. But I did also say that it doesn't matter, you can connect how you want! [/quote]+1. You probably won't hear it, but daisy chaining does result in the cable connected to the amp carrying twice the current than otherwise. [quote]There's an audible difference between my rig with a brand new Stagg speakon and an OBBM speakon. That's not imagined, I've done a double blind test. I could always tell the difference between the two with 100% accuracy. The OBBM cable sounds that much better.[/quote] 'Better' is the wrong choice of words, technically speaking. No cable can make anything sound better. OTOH, a poorly built cable can make something sound worse.

This interesting tidbit came my way today: [url="http://consumerist.com/362926/do-coat-hangers-sound-as-good-monster-cables"]http://consumerist.com/362926/do-coat-hang...-monster-cables[/url]

WinISD will do dual chamber bandpass reflex, but you have to tweak the parameters manually. It's probably the least useful cabinet type for MI use as it has a very narrow passband and is extremely fussy to realize. It also demands a full crossover, by either bi-amping or passive, both being expensive propositions.

[quote name='BMoney' post='149562' date='Mar 1 2008, 01:46 PM']is it worth spending 60 quid on a cable or am i better of getting a cheapy cable? .[/quote] No. Allow no more than three pounds per meter, another five for the connectors.