Bill Fitzmaurice

[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.

[quote name='OzzyGreg' post='1216237' date='Apr 30 2011, 07:24 PM']Can anyone who is familiar with speaker design software PULEEEEZE run these figures and see what [b]you[/b] come up with? (I ended up with 65 litres for a twin driver box.) Greg[/quote] Your drivers are unsuited for electric bass, the Fs is too high, the Qts is too low, and since xmax is not listed there's no way of knowing their actual power limitations. And you should not be running the drivers placed horizontally, as that halves their dispersion. [quote]WinISD is useful because lots of people here have experience with it, so can point out how to use it.[/quote]It's as good a design tool as any. It also has the same limitations as any tool: you have to know how to use it, and how to interpret the results it gives you. In the OPs case my guess is that he correctly used his program to get the best result possible from the drivers he chose, the problem being he didn't choose the right driver. One uses software to design the right cab for a driver, but a far more important use for it is to make sure one chooses the right driver to begin with. IMO these drivers should not be marketed as electric bass drivers at all, but ultimately it comes down to the consumer having to determine driver suitability, rather than blindly trust the manufacturer.

[quote name='Arrakis' post='1215713' date='Apr 30 2011, 07:24 AM']Well im looking at getting some 12" Bass drivers and there are alot on the market. I was hoping that people could give their opinions and experiences on the differnet ones availbale on the market I havent been able to find any comparisons anywhere. Im kinda looking at Celestian Neo green labels or Eminence Delta or Deltalites.. whats the general consensis?[/quote] Choosing the right driver is literally a scientific endeavor, it's not a popularity contest. It begins by understanding what all of this means: [url="http://www.eminence.com/support/understanding-loudspeaker-data/"]http://www.eminence.com/support/understand...udspeaker-data/[/url]

[quote name='EddyGlee' post='1214178' date='Apr 28 2011, 03:50 PM']hey Bill .. the standard Delta-12 isn't even that good mate with only 1.6mm xmax![/quote]The 'Standard' Delta 12 no longer exists, except as eight year old NOS. The 12A is 8 ohms, B 16 ohms. If there was a C it would be 4 ohms, but there isn't. The LF models are technically subwoofer drivers, but quite obsolete really, having no more xmax than the current neo fullrange drivers. [quote]Is that for one or 4? 50 watts each in a 4x10 sounds enough.[/quote]Talking about the Delta 12 here. Rather than use four in a 4x12 I'd use two twelves that can handle 100 watts, for half the cab size and half the cost. When you get down to it the Beta 12 actually is better than the Delta. But the thermal rating of the Beta is 250w, the Delta 400w, and what sells is watts, not xmax. More than a few manufacturers have used Deltas when they shouldn't have based purely on the wattage ratings.

[quote name='EddyGlee' post='1214031' date='Apr 28 2011, 01:15 PM']ps.. Delta-12(8 ohm) For high power bass in sound reinforcement systems, bass guitar combos, club music systems and stage monitors. Eminence words not mine!! Chris[/quote]Eminence isn't above recommending drivers for more applications than they should. It's up to the consumer to check the specs and make sure of suitability. With only 2.4mm xmax I don't recommend it for bass unless it's for use with less than 50 watts. IMO 4mm is the minimum acceptable. 2.4mm is OK for what it should be used as, PA midbass, just like its smaller sibling.

[quote name='squire5' post='1213929' date='Apr 28 2011, 11:21 AM']Chris,the blurb on the Eminence website says that the Delta 10 is optimized for lead guitar[/quote]Not the Delta 10. BTW, where it works best is in a PA top, the low end is too thin for good results with bass.

[quote name='squire5' post='1213864' date='Apr 28 2011, 10:01 AM']These 2 drivers cost me a ton,so I'm relying on Eminences reputation to win through.[/quote] They shouldn't have, it's the least expensive driver they make. In any event should you have to do any more driver replacement first choose the appropriate model based on the driver T/S specs and how it models in your cab, not the recommendation of a retailer. If the retailer really knew what he was talking about he'd be designing drivers and speakers, not selling them.

[quote name='Arrakis' post='1210371' date='Apr 24 2011, 04:13 PM']I was thinking deltalites mainly for the weight issue Matamp 4x12s are heavy enough lol[/quote]Deltalite II 2512s need about two cubic feet[i] each[/i] for a good result. As already mentioned you can't just stick a bass driver in a guitar cab to make it a bass cab. Running the two with separate amps is the best option.

[quote name='waynepunkdude' post='1204103' date='Apr 18 2011, 03:30 PM']Anyone got any info on these, I know Neil Young uses one as a guitar cab, I've heard you can get them as a 6 X 15 + 4 X 12 but can't find any info. [/quote] I vaguely remember seeing one or two of them in the 70s. They look impressive as all get out, but the side by side mids and tweeters indicate that the designer had no acoustical engineering knowledge, and if looks alone didn't confirm that the resulting sound would leave no doubt.

[quote name='arthurhenry' post='1201118' date='Apr 15 2011, 03:05 PM']My 350 Watt Hartke head was putting out, I think about 240W into my 8ohm cab. The volume hardly ever went above 2, even on loud rock gigs. Last night I used my new Hartke LH500 for the first time. This puts out 350W into the same cab. The volume was on 6! Why?[/quote]Gain structure. Google it.