Bill Fitzmaurice

[quote name='Billy Apple' timestamp='1380976176' post='2233015'] I think the OP should get in touch with Eminence themselves and see what they have to say. I had a question about removing the sealing gasket from the front of an Eminence Basslite driver. The supplier said it should not be done, could cause the cone to come unstuck and void the warranty. Eminence said it could be cut down, or indeed removed completely. They said the adhesive that sticks the gasket on is different to the one that glues the cone to the chassis, and the presence (or not) of the gasket does not interfere with this. [/quote]It should not be done, for two reasons. One is that there's nothing to be gained in so doing, so if it ain't broke don't fix it. Why one would decide to remove it is beyond me. The other is that in the process of removing it one might pull the suspension from the frame, and even the smallest air leak there could lead to driver failure. [quote]I'd seek the advise of the people who built it. BTW took Eminence less than a day to respond, the supplier took a week! [/quote]Suppliers/distibutors employ sales, advertising, customer service and shipping personnel, not transducer engineers.

[quote name='AndyKos' timestamp='1380853245' post='2231590'] recognising the name Bill Fitzmaurice,Im curious are you the same Bill Fitzmaurice thats linked to numerous speaker designs, [/quote]Guilty as charged.

[quote name='Mr. Foxen' timestamp='1380838496' post='2231478'] So that's two counts of Blue Aran staff not having the first clue about bass cabinets then. [/quote]I agree to some extent, though it falls upon the customer to do the proper research to be sure that they are purchasing the correct driver for a particular application, not the retailer. I don't expect a retailer to have a high degree of engineering expertise. Of course, if the retailer does assume the position of giving applications advice, other than merely reposting manufacturer specs and data, then they have the obligation to be sure that they get it right. In short, don't offer expert advise if you're not an expert. Still, I put the onus on the OP in this case. I'd be curious to see exactly what research he did. For instance, did he ask here before making his purchase?

[quote name='skidder652003' timestamp='1380655076' post='2228594'] There are numerous possibilities, including the fact that the speaker simply was not compatible with the cabinet you put it in.[/quote]That sums it up. How did you choose this driver? There's far more to be considered than just inches and watts.

[quote name='alexclaber' timestamp='1380620797' post='2227845'] The driver in question is excellent for bass guitar. The damage is a clear case of both excursion and thermal overpowering. . [/quote]+1. As is the case with any and all drivers it must be loaded into a cab that is compatible with its specs. If one is to push it to maximum output the amp must at the very least be appropriately high passed, if not limited to the driver's safe operating voltage swing. It must have sounded really bad for quite some time to have sustained the damage that it did. Distortion is the driver's way of telling you that you're pushing it too hard. In terms of performance the 3015 is on par with an Aston Martin. One would not expect Aston Martin to honor a warranty replacement claim should one drive it into a grove of trees.

[quote name='Roland Rock' timestamp='1380204281' post='2222279'] I've just discovered something very interesting, considering one of my amps is a Streamliner 900. I was researching Thumpinator on BC, and this came up on the subject of high pass filters: [/quote]Many amps incorporate HP filters, it greatly reduces warranty claims on blown drivers.

[quote name='Roland Rock' timestamp='1380186581' post='2221909'] I have ordered a low pass filter, as two of our songs are in a dub reggae style, and I'd like to get that pure deep deep tone. [/quote]Just turn down the high and mid EQ on your amp. [quote]So the question is, what happens if I boost a frequency below the "usable range"? Will I blow my speakers? [/quote]Quite likely. The 'usable range' takes into consideration not only frequency response but also the driver excursion limit. Boosting below that range may result in over-excursion, causing both thermal and mechanical driver damage.

[quote name='jdt' timestamp='1379880873' post='2217805'] just wanted a 2x10 to go with 2x10 markbass cab, was thinking of a 112 fender cab, [/quote]Whatever you're thinking about don't pull the trigger until you've actually tried the two together, as there's no way to predct the result. The only safe combination to go with without hearing it first is two identical cabs, which will sound the same as one, but louder. Beware the urge to add a different cab to make up for deficienies in your existing cab. If, volume aside, your current cab doesn't sound good, don't try mixed cab voodoo to fix it. Get rid of a cab that you don't fully like and replace it with one that you do.

[quote name='geoffbyrne' timestamp='1379420363' post='2212410'] I'm pretty much going to replace both of these little speakers (they're all fine, by the way) with a single 12", 8 Ohm rated somewhere near 150W-ish. [/quote]Bad idea. You need response to at least 10kHz. Useful response from a twelve is no higher than 2kHz before it beams so badly that you can't hear it more than a few inches off-axis at the range monitors are used at. Unless the drivers are damaged leave them alone. The above assumes you're using them for vocals. If you're intent is to use them for bass, along with a backline amp, that's a bad idea as well. You may be doing so with the intent of hearing yourself better, but if the backline amp and monitors create null zones in the space between them it will have the opposite result.

[quote name='Wolverinebass' timestamp='1379193037' post='2209771'] Surely GB would have been making money? [/quote]Obviously not enough not to accept the Fender offer. As for Fender retiring the GB brand, it wouldn't be the first time a large company has bought out a smaller company just to eliminate them as competitors, with no intention of preserving the brand.

[quote name='goblin' timestamp='1378650524' post='2202767']I know the 1000 watt ones have a fan in them, I'm wondering if there's anything else I can do to aid cooling, including potentially fitting a fan inside of one. I don't want to rack it and have a fan in a rack case, as that would then defeat the point as it'll be no more compact than the Hartke! [/quote]Racking it is the only practical method of fan cooling it. It does work, though.

[quote name='wateroftyne' timestamp='1378459557' post='2200513'] I'm quite happy to state that (so far) Neos don't seem to ring my bell, without being too bothered by the 'You don't understand the theory - they're no different other than the weight!; responses I invariably receive. :-) [/quote]They are different. Neo allows longer excursion, not because of higher flux, but because the motor structure is more compact. Longer excursion results in higher output with less distortion. Most of us prefer that to lower output with higher distortion, but I guess not all.

[quote name='Corvine' timestamp='1378157229' post='2196519'] Will I get more volume from one cab than another? Can this harm the amp/cabs, or just that it might not sound so good? [/quote]All of the above. The only totally safe and totally predictable combination is identical cabs.

[quote name='Corvine' timestamp='1378155219' post='2196477'] On an amp that goes to a minimum of 2 ohms, and has 2 speaker out-puts, it's ok to have a 4 ohm cab on one out-put and two 8 ohm cabs (in parallel) on the other out-put. [/quote]It's OK, but chances are slim to none that the cabs will have equal power distribution.

Impossible to say, but the small AlNico magnets reveal them as generic musical instrument drivers, so I would not consider them for bass.

[quote name='hamfist' timestamp='1377252793' post='2185276'] Maybe, for passive basses, the higher the impedance output of the pickup, the more they lose signal, and tone, with longer cables? It's a theory anyway . [/quote]It's a fact. When the impedance of any source is particularly high it makes the capacitance of the cable a major factor in high frequency losses and noise pickup. The higher the impedance the worse it is. The cures are lower source impedance and/or lower capacitance cables. Since capacitance is proportional to cable length that also enters the equation. Capacitance and cable length tend to be non-issues with line level/buffered sources, such as those in actives, where the source impedance tends to be less than 1kOhm, as opposed to 10kOhm and higher with passives. [quote]I chucked it away it was so bad. Is this an issue with curly leads [/quote]Coiled cords have the worst capacitance imaginable, and also high inductance, which makes them doubly bad.

[quote name='fuzzonaut' timestamp='1376680302' post='2178056'] just stumbled across an odd looking cab, it's a 3x15", and the owner claims it's good for guitar [b]or[/b] bass, which I thought can't be the case.. [/quote]Judging by the small dust covers those drivers may be generic musical instrument drivers from the late 60s or early 70s, which were used for both guitar and bass. By modern standards they wouldn't work very well.

Found my schematic, it uses the Alto PM12 Dragonfly power amp module. The input chip is a TDA8929.

[quote name='BassBunny' timestamp='1376501908' post='2175073'] There is also Alto the Italian PA company. they are distributed/repaired by Proel. [/quote]+1. Nearly everything in the Superfly was sourced there. Some of the boards have the Alto name on them, probably shared by Alto branded gear.

[quote name='apl4' timestamp='1376471815' post='2174266'] Does anyone know where I could get a replacement board? [/quote]Try Alto, that's who made them. Once upon a time you could download the schematic from Ashdown, but that was when they were in production and you probably didn't need it, as opposed to now, when you do need it.

[quote name='Ashdown Engineering' timestamp='1376076703' post='2169560'] The published specs are 100% correct(yes the specs are huge)and we are happy for anyone to test and check. We don't overinflate specs like some other manufacturers out there might.. ;-) [/quote]The only specs that matter IMO are a measured SPL chart and the driver displacement. Playing Devil's Advocate, the 25Hz - 20kHz at 98.5dB 1m/1w listed for the ABM210 is impossible to realize, unless said response is at least -20dB at 25Hz. The same applies to the claimed combination of low end response versus sensitivity for the 1x15. And 'front-ported for maximum forward dispersion' isn't a claim that came from the engineering department, or I'd surely hope not, as they should be aware that the radiation pattern of port output is omni-directional. I'd say that the marketing department is writing cheques that the engineering department can't cover. I'd like to be able to take you at your word, but I'm afraid the reality of the physics won't allow for it.

[quote name='grenadilla' timestamp='1375385650' post='2160679'] That cabinet with 4 8s is interesting. I have heard of Sica speakers but not an 8 that can handle hundreds of watts. [/quote]Thermal ratings mean next to nothing. Chances are the eight is this: [url="http://www.sicaspeakers.com/speaker/pl8b25s"]http://www.sicaspeak...speaker/pl8b25s[/url] It will only handle 100w before reaching maximum excursion, and the response plot isn't very good. The ten is likely this: [url="http://www.sicaspeakers.com/speaker/pl10b25s"]http://www.sicaspeak...peaker/pl10b25s[/url] and the the fifteen this: [url="http://www.sicaspeakers.com/speaker/pl15b3s"]http://www.sicaspeak...speaker/pl15b3s[/url] and they're OK, but far from stellar. They're no competition for the Eminence drivers that Barefaced uses. They're much better than the cheap Blue Line Ashdown drivers, but that's not a high bar to clear.

[quote name='Mr. Foxen' timestamp='1375888657' post='2167006'] Watt ratings are meaningless, so its all not worth considering. Its a thermal rating, and thermal has nothing to do with sound, or the point where the cab farts out, or where it breaks. [/quote]+1, useful power handling is determined by the driver xmax, and said useful power handling can be as little as 20% of the driver thermal rating. To find out what a driver can really do you need its T/S specs and then use speaker modeling software to model its capability in the cab that its loaded in. That will give you the displacement limited power handling, which in a perfect world all speaker manufacturers would provide, but the world is far from perfect.

[quote name='xgsjx' timestamp='1374493352' post='2149251'] Foam pads on the walls might help reduce the vibrations as well as a floating floor (Gramma pad, small drum riser, etc). [/quote]Foam will absorb midrange and high frequency reflections within the room, but it will do nothing to stop low frequencies passing through walls, ceilings and floors. Gramma pads don't do anything to stop low frequency passage. The only thing that stops low frequencies is mass, a lot of it.

The output voltage of a loop typically runs 1v at 600 to 1000 ohms. That makes it not a good match for floor pedals that expect maybe 100mv with the 25kohm output impedance of a bass.