stevie

The frequency response is exactly what you would expect from fitting a speaker in too small a cabinet. The Trace 1153 is similar, although not quite so bad. The measured frequency response starts at 40Hz here and finishes at 250Hz. It's not a pretty sight. The word is boomy.

I measured the impedance of the cab, and it is tuned to 50Hz. Too high. We can sort that out by lengthening the ports. I've used Pringles tubes before and they may work again here.

Snap! I also have an ABM Mini (purchased yesterday from a very nice Basschatter) with a faulty drive unit - just like yours. Mine is only starting to go, as there is no coil rub yet - but it's certainly on its way out. I'm fairly sure that incorrect cabinet tuning is the cause of the failure. My back-of-a-fag packet calculations show the cab is tuned to about 55Hz, which means the speaker will only handle about 10 watts of low E. So, driver failure has been built in and is just a matter of time unless you're using it in your bedroom. I'll measure the cabinet tuning some time soon, and when I've managed to persuade the driver to come out (I thought it had been glued in!!), get the Thiel Small parameters, which will show us the type of driver they've used. This cab is roughly 45 litres in volume (much smaller than I was expecting), which is much too small for just about every 15 I know - but a good volume for a 12. In other words, there is no benefit in fitting a 15 in here, because a 12 will produce just as much bottom end. Given the excessive profit margins manufacturers make on spares, I would hesitate to replace the driver with another of the same. A budget, lightweight option would be the Celestion TN neo 12" available for about £50, but you will need to fit a panel of 1/2" birch ply over the front baffle first. The 15" Celestion TN neo costs £25 more but will not actually provide any more bottom end (because of the small cabinet size). Plenty of quality 12" drivers will work in here though. Bear in mind that the cabinet should definitely be re-tuned lower - or else the same thing will happen again. As long as you're not in a rush, I can post my results from time to time for your guidance. Incidentally, I sent an email to Ashdown yesterday late afternoon (about getting the speaker out) and they responded this morning. Very impressive!

Phil can't help living in Birmingham. Maybe he was born there - or maybe he has to live there because of his job. *Don't* hold it against him: he is a standup bloke. Sold me an excellent Ashdown ABM cab. Haggled in a very civilized way, packed it up really well, called me up to advise of progress, and was a pleasure to do business with. Thanks, Phil.

Don't even think of it - it would be money down the drain! Plastic handle, plastic corners, piezo tweeter. It's a cheap and cheerful home-made confection that should be on Freecycle. The single 3-inch port will fart when you play low-E. And it's filthy, which speaks volumes about its owner. I'll bet you the cabinet is made of chipboard and there's an old, cheap, pressed steel Eminence of Chinese driver inside. Avoid it like the plague and wait for something half-decent to come along.

[quote name='Bill Fitzmaurice' post='526719' date='Jun 28 2009, 02:15 PM']No higher than 1.5kHz. The axial response of the 15 may well go to 4kHz, though if it does go that high I'd be concerned about its low end, that's very much in the realm of a guitar driver. But irrespective of how high the axial response is any fifteen's response drops like a stone off-axis above 1.5kHz at best.[/quote] If you try to cross a tweeter over at 1.5kHz you'll blow it up within a few minutes. Most of them are designed to be crossed over between 4 and 6 kHz. A very few will go down to 3 with a steep crossover, but 1.5k is the domain of the 1-inch compression driver - and high-end compression driver at that. The crossover point for a tweeter is a function of its resonant frequency and the steepness of the crossover being used. Your Fane starts rolling off at 3KHz - so you should try for a crossover point of 4 or 5kHz, certainly no lower if you're just using a high pass.

[quote name='Protium' post='526297' date='Jun 27 2009, 09:39 PM']How do If I want to wire up an 8ohm tweeter with an 8ohm woofer do I need a full crossover or can I get away with just using a high pass filter @ 4kHz on the tweeter?[/quote] Unless you have measuring equipment, you don’t really have any option and it will be a bit hit and miss. Still, it can be done. What type of crossover were you thinking of using? Do you have specific drive units in mind? I’ll try to point you in the right direction if I can. Here's an example of somebody who's done it: [url="http://www.humblehomemadehifi.com/Bass-Rig.html"]http://www.humblehomemadehifi.com/Bass-Rig.html[/url].

[quote name='Mr.T' post='524612' date='Jun 26 2009, 09:34 AM']Is it even a fair shoot-out?[/quote] It's only a fair shoot-out if you realize that the two types of cab offer different benefits. *All things being equal* (and I'm not referring to any brand here), a 15" will be louder and go lower. It's maximum output will also be greater. A 12" will be more compact and thus easier to transport. It will also have cleaner mids, a more extended high frequency response and a slightly better off axis response. Which is better will often depend on what you're looking for.

[quote name='alexclaber' post='524841' date='Jun 26 2009, 01:52 PM']I don't think anyone who's bought one has directly replaced a GS112 with a Compact. An Epifani UL112 owner who recently got a Barefaced Compact said this: "Having had the Compact a few days now and used it for two rehearsals yesterday I can confirm that it is superb smile.gif Just has so much more depth that my Epifani 1x12, much fuller across the whole range, punchier, lighter and a lot louder (I know it's not a fair comparison but even so). I've used the mid and treble eq on my Overwater in a way I never had before - the amp is set flat as usual but I can dial in mids and top end without it sounding all edgy and harsh. My new passive Fender Jazz sounds great through it too - so all in all extremely happy" Alex[/quote] The question wasn't about the Epifani UL112 but that's another nice plug for your product. Alex, how would you like it if other speaker manufacturers came on here and trashed your stuff?

That is such a brilliant album (apart from that awful Windmills track) with some very tasty bass playing.

[quote name='JTUK' post='511592' date='Jun 11 2009, 08:42 PM']Yes, nothing to put them in.....and I did indeed think about getting some 1x15 cabs made....never got round to it and I have that base ( no pun int' ) covered now... I'll dig them out and see what they sound like... and then put them on here for offers[/quote] That's a good idea. You haven't got any 2206s that you would like to dispose of (very cheaply) have you?

[quote name='alexclaber' post='514331' date='Jun 15 2009, 03:57 PM']Nothing will move more air for the money than the 3015LF.[/quote] This will - much more. [url="http://cgi.ebay.co.uk/p-audio-p210-254-21-driver_W0QQitemZ130312286006QQcmdZViewItemQQptZUK_ConElec_SpeakersPASystems_RL?hash=item1e5737af36&_trksid=p3286.c0.m14&_trkparms=65%3A12|66%3A2|39%3A1|72%3A1683|240%3A1318|301%3A1|293%3A1|294%3A50"]http://cgi.ebay.co.uk/p-audio-p210-254-21-...93%3A1|294%3A50[/url] Put it in a 200/50 litre box and you won't look back. Just make sure you have money in your budget for some castors.

[quote name='JTUK' post='510068' date='Jun 10 2009, 12:23 PM']Original thought was to replace both with Eminence Deltalite II 2510's and get a weight save at the same time...but that would mean 2 chassis lying around...and I have enough of those already...albeit JBL 15's etc..[/quote] You've got JBL 15s just lying around. What are you - nuts?

[quote name='redstriper' post='505963' date='Jun 4 2009, 11:35 PM']Cheers Stevie (again) I'm not going anywhere...............[/quote] There was a thread on flats a few weeks ago when Geejay (Graham) generously offered up a used set of Ernie Ball flats and I got in there just before you. He said at the time that, if I decided not to keep them, you were next in line. Well, I tried them and liked them but I just couldn't get on with the gauge - they're 55 - 110s, the equivalent of telegraph wires. They put enormous pressure on the neck and slow my playing down. I like 55- 110 roundwounds, but these are something else. Anyway, I decided I should take the plunge and get myself some TIs. Unfortunately, when they arrived, the D was duff and I've put the Ernie Ball Chromes back on my bass while I await a replacement set. Funnily enough, this ties in with BottomEndian's post. I'll send you the set on as soon as I'm sorted and let you know when to expect them. If you try replacing the bottom three strings on your bass with the top three strings on this set, the tension and the sound won't be a million miles away from the sound of TIs. They are third-hand now, but I don't think they've been used much, as they still have a reasonable about of sparkle. Geejay asked me to cover the postage by giving a pound the next time I passed a charity box. So that's the deal for you too. And if they don't suit you, just pass them on to someone else on the list.

[quote name='redstriper' post='505952' date='Jun 4 2009, 11:22 PM']Do you want to sell me your old La Bellas cheap? I want to try some for size before I buy a new set. I'd also like to try some TIs if anyone's getting rid of an old set.[/quote] If you can hang on, I have a set of flats for you to try. More info tomorrow.

[quote name='fatgoogle' post='505779' date='Jun 4 2009, 08:04 PM']Ive been reading over that, reading over the Electro voice sheet and looking in the shed. Just to make sure i have plenty of 1/2" ply in the shed, but on the cab specs, it says to use 3/4" i reckon ill be grand just making sure. Yep and reading it blocking of the middle square port at the bottom will give me 1 1/2 octave extension in the low end i believe. It would easier for me to do the diagrams build with the square ports as my routers not great so the more round ports the more likely it is to go off.[/quote] I didn't realize you'd originally used 1/2" ply, and that's certainly another reason to go for a smaller cab. An unbraced 150-litre cab in 1/2" ply will resonate like mad at volume. Anyway, if you're going to use 1/2 ply, you must make sure you've got lots of bracing in there. Dig around on this forum: [url="http://www.talkbass.com/wiki/index.php/Fearful%E2%84%A2_12/6_%26_15/6#Crossover_designs"]http://www.talkbass.com/wiki/index.php/Fea...ossover_designs[/url] where there are lots of examples and pictures of some bass cabs made with 1/2" ply. The bracing you see in there is the minimum you should use. I'd also strongly recommend that you double up on the front baffle, i.e. glue two pieces together to give you one inch thickness. It won't be much heavier than a 1/2 inch baffle - because of the big hole in the middle - but it will be a lot stiffer. And post the results of your efforts in the DIY cabs section for us all to admire!

[quote name='fatgoogle' post='505706' date='Jun 4 2009, 06:51 PM']So i could make the same size box as in the diagram, and then just use two ports, sound ok, If you have time to work them out that would be great and i can decide which one to go with. Is the Electro voice one already tuned the way it is, so you make it and plonk the speaker in, or does some self calculations have to be done after building.[/quote] Your 100mm ports should be 180mm in that cab. If you want to design the cab specifically for 5-string, you should lengthen the ports - 245mm is optimum, but anything approaching that will help power handling on the low B. The cab will handle low B better than the one you have now. There are two tunings available on the EV cab. You need to use the lower of the two, which as far as I can figure out, involves blocking up part of the slot port. Have a look here: [url="http://basschat.co.uk/index.php?showtopic=380"]http://basschat.co.uk/index.php?showtopic=380[/url], where Below has made a very nice job of the EV cab.