Bill Fitzmaurice

[quote name='alexclaber' post='1253585' date='Jun 2 2011, 04:49 AM']I'd take most sensitivity specs with a whole bucket of salt! [/quote] More like a lorry load. Doubling power gets you 3dB. Doubling your cab count gets you 6dB with the same amp. Unless your amp is severely underpowered, as in 1/4 or less than the power rating of your speakers, adding a second identical cab will usually be the better route.

[quote name='OzzyGreg' post='1256177' date='Jun 4 2011, 02:46 AM']. Guys, I'm not real handy with speaker box design software, I'm very much a beginner. I have just used WinISD to calculate the design of a new 15" bass cabinet I want to build using an old Etone 461 bass speaker I have lying around here. The speaker's parameters are, according to Etone: Fs : 35Hz Vas: 253 Qms: 6.1 Qes: 0.34 Qts: 0.322 PMax: 250 W (RMS)[/quote]Those specs alone are insufficient to determine driver suitability. Also required is xmax, to know the displacement limited power handling, and an SPL chart, for midrange response. Unfortunately Etone doesn't publish either xmax or SPL charts, so a proper simulation is not possible.

[quote name='Subthumper' post='1246754' date='May 27 2011, 05:21 AM']Was wondering if it would be any good in the BFM omni 15 cab.[/quote] Yes.

[quote name='fryer' post='1242562' date='May 24 2011, 02:11 AM']Thanks Bill, and all. But I do like the sound of the Peavey cab, and prefer it to the sound to my Epi UL 410. What makes the sound though - is it the speakers or the box ?[/quote]Both. But in this case mainly the drivers, which have a high Qts that results in a pronounced midbass response peak. It's not my response cup of tea, but if you like it all well and good. [quote]If I made a new cab from ply, to the same internal dimensions, with the Sheffield speakers, would it sound the same as it does now ?[/quote]Properly built with cross-bracing and internal damping, probably better.

[quote name='reggaemaster' post='1242353' date='May 23 2011, 05:07 PM']Thanks for the info, but will the fact that there is more power running to the the 2 110's make any difference?[/quote]Not if they lack the displacement to use it. The average ten runs out of excursion at about 100 watts. [quote]Epis are 99db. GKs, depending on which model are either 100db or 101db[/quote]Only in the imaginations of their respective advertising department schlockmeisters.

Volume is limited by the displacement of the drivers. The average twelve has more displacement than the average ten, so a 2x12 will usually have more output capability than two 1x10s. I say usually, as a particular ten may have more displacement than a particular twelve. Unfortunately manufacturers won't tell you what the displacement is of the drivers they use.

[quote name='deepbass5' post='1240034' date='May 22 2011, 04:38 AM'][b]No don't do it[/b] is the answer these mass produced cabs are made from fairly cheap light weight stuff anyway[/quote]Au contraire, price point gear like Peavey tends to be made from thick heavy materials with un-braced construction, as that's the most inexpensive method. I suspect this is made of 18mm MDF or the like, as the Sheffield tens only weigh 1.8kG each. Build of well braced 12mm plywood it's possible to reduce the cabinet weight by at least 15kG. But I wouldn't. The Sheffield drivers are mediocre quality, and the 4x10 format is perhaps the worst possible for an electric bass cab. If the OP has the skills to duplicate the Peavey cab he has the skills to build a pair of 2x10s, which will work better, and they could be loaded with far better drivers than the Sheffields.

Mine are whatever sounds best in the room I'm in. Since every room is different acoustically my settings are different in every room .

[quote name='JPJ' post='1228081' date='May 11 2011, 04:27 PM']At coppers short of £300 including delivery they weren't a cheap upgrade[/quote]If you plan to get more do so yesterday, that's a silly low price considering what's happened to the price of neo drivers in the last 6 weeks.

[quote name='Bloc Riff Nut' post='1226365' date='May 10 2011, 11:10 AM']I think my thread will get a more positive response on TB [/quote]Or not. They're also sensible enough to know that the only thing that differentiates heavy gear from lightweight is that heavy gear weighs more. [quote]BUT..I have recordings of a 1x15/210 config over 2x1x12's and the sound of the latter does me fine atm[/quote]Moot. All that proves is that you prefer one recording to another. A recording is only as accurate as the gear it was recorded with and listened to on.

[quote name='JPJ' post='1225198' date='May 9 2011, 10:30 AM']Fair point I think what I meant to say was the difference between the stock PAS speakers and the DeltaLiteII's [/quote]That would probably be significant. The PAS being OEM are probably not high quality, and being ceramic are an old and probably obsolete design.

[quote name='JPJ' post='1224886' date='May 9 2011, 06:08 AM']I should get a really interesting 'real world' comparison between neo and non-neo speakers.[/quote]Aside from weight there is no difference between neo and non-neo drivers. There are differences between various drivers, but those differences are not the product of the magnet material.

[quote name='Mr. Foxen' post='1224479' date='May 8 2011, 03:30 PM']Depends on the speaker. The cab has to be tailored to the speaker. Throw up what they are, and a bunch of loudmouth internet know-it-alls will give suggestions.[/quote] More to the point choose the cab design based on your needs, use a driver suitable for it.

A loud popping is either the amp running out of headroom or the driver voice coils hitting the back plate. Neither is recommended. The cab wattage rating is irrelevant, few cabs can make use of more than half their rated power, and if pushed to full power the drivers may very well bottom out. I would not bridge the amp. 225w/8 ohms per channel is all your cabs need, so run dual mono. All that you're accomplishing with bridging is doubling the voltage swing, which doubles the likelihood of damaged drivers.

[quote name='Stompbox' post='1224336' date='May 8 2011, 01:29 PM']Following on from my earlier post, I'm acquiring a pair of 15" bass drivers - now I'm thinking about building a 2 x 15" vertical cab. How about one that will clip together (but have an open base on the top cabinet, and an open top on the bottowm one, if you see what I mean,) so as to make it more portable? Hmmm... [/quote]Just make two 1x15.

[quote name='JPJ' post='1224066' date='May 8 2011, 07:45 AM']Thanks for that, more or less confirmed my thoughts/fears about the neos so it looks like Delta's it is.[/quote]Model them both in WinISD Alpha Pro, look at the maximum SPL chart, and you'll see the Delta is an also-ran. Even the Basslite S2010 beats it, let alone the 2510.

[quote name='mcnach' post='1222580' date='May 6 2011, 03:49 PM']For gigs I often use a 410 with a 210 on top... I think I will try putting the 210 vertically next time and see what happens... would it make sense to align the speakers with the ones below... or not really bothered? [/quote] It may work better, hard to say, as the setup is already knackered by the horizontally placed drivers in the 410.

[quote name='gusthebass' post='1220622' date='May 5 2011, 04:05 AM']the line itself has to have the cross sectional area of the cone at the speaker end to avoid pressure changes[/quote]It doesn't, just as a reflex port does not have to have the area of the cone. [quote]with wadding you can slow the speed of sound[/quote] Not enough to make any difference. TLs are very misunderstood, and it doesn't help that there are many proponents of so-called mass loaded TLs that aren't TLs at all, they're tall skinny bass reflex cabs. It's all in the impedance. A TL has a single impedance peak, just like a sealed cab. If the cab has dual impedance peaks it's bass reflex. [quote]These may be great speakers but I wish people would be honest[/quote]Truth in advertising? What a novel concept.

[quote name='Phil Starr' post='1219241' date='May 3 2011, 04:57 PM']the easiest one to answer is your transmission line question. Although there are some technical controversies over these the whole point is to absorb the rear pressure and to stop it reflecting back to the speaker so you lose all the energy from the rear of the speaker and you have a decent mass of air in the line. Transmission lines promise lower resonance and smooth low end response with good transients but low efficiency.[/quote]Transmission lines are 1/4 wavelength resonant pipes. The 1/4 wavelength resonant frequency coming out of the terminus acts much like the port in a bass reflex. The line is stuffed with damping material to suppress the harmonics of the pipe frequency. The advantage to a TL is that below the pipe frequency response rolls off at 12dB/octave, like a sealed cab, rather than the 24dB/octave of a bass reflex, so you get sealed cab 'tightness' with reflex efficiency. The downside is that they need that 1/4 wavelength pipe, which is 5.7 feet for 50 Hz, 7 feet for 40Hz. They're just too big to be practical for electric bass.

[quote name='dan670844' post='1219010' date='May 3 2011, 02:08 PM']He its not a new idea WEM where doing it in the 60's and also had double angled cabs with 6 drivers in but they didn't catch on prob didnt look cool even though they where most def better than all the other crap and the time....................[/quote] The proof of concept can be seen in St.Pauls in London; the original installation was done in 1949. Acoustical engineers knew that was the right way to do multiple driver cabs for a decade prior to that. Needless to say Leo Fender and Jim Marshall were not acoustical engineers.

[quote name='Mr. Foxen' post='1218624' date='May 3 2011, 09:32 AM']Not sure that that is true, the woofer/mid ones are all about using tons of power to move loads of air in a small light package, and the small ones are for being able to take tons of power while still being small. The idea is they have a variety of sets of compromises in the line up.[/quote]+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.

Every time you double the number of drivers you increase dB per watt sensitivity by 3dB, so yes, an 810 is more sensitive than a 210. You also completely alter the dispersion pattern with an 810 versus 210, especially if you have the 210 with the drivers horizontal. That's the usual alignment, and the worst way to place them. Accurate, honest SPL figures are simply not available. Most manufacturers couldn't show an SPL chart if they wanted to, because they don't have any. If you like the 810 sound but don't want to haul one use two 210s stacked placing the drivers on a vertical line. In most cases output will be adequate, and with no drivers horizontally placed dispersion will be better than an 810.

[quote name='icastle' post='1217784' date='May 2 2011, 12:24 PM']More detailed information is in the user manual available [url="http://www.ampeg.com/pdf/SVT450H.pdf"]here[/url].[/quote] Man Law #1: Never ask directions. Man Law #2: Never read manuals.

[quote name='OzzyGreg' post='1217343' date='May 2 2011, 06:18 AM']Strangely, these speakers from this Australian company (Etone, not Eton BTW) are highly respected from my observations over the past 20 years or more.[/quote]Unfortunately their data sheets, such as they are, look to be 20 years old. Look at the driver data sheets at Eminence and you find complete data, including SPL charts. They also have basic cab designs for most drivers, which show in-box response below 200 Hz, and list their displacement limited power and useful low frequency limits. If I was going with six tens I'd use Beta 10s or Basslite S2010. I wouldn't use six tens, but that's another discussion.

[quote name='0175westwood29' post='1216487' date='May 1 2011, 07:28 AM']im guessing theres some sort of mixer that goes between the amps and speaker? andy[/quote]No. You need to use two speakers. The one for dirt would best be a guitar ten or twelve.