Phil Starr

Hi, you are getting good advice here. Bill designs speakers for a living and I used to design speakers. There's no disagreement between us because the maths/science points in one direction. The delta 15 isn't a great choice of speaker unless you want a very coloured sound. You may have chosen this because you've heard one and liked it or because you have some theory you want to chase. If you've chosen the delta on price or because of some sort of deal then we are telling you that there are better speakers out there. If you want to go ahead then the 100l cab I suggested seemed a reasonable compromise in the few minutes I spent modelling this speaker. Any larger and it will become a monster you never want to move, much smaller than this and it will have a huge bass hump that swamps your sound and you will lose all your deep bass. As it stands this would peak at nearly an octave and a half above bottom E. In any case Bill is telling you that this speaker is excursion limited at low frequencies so that the speaker will start to distort at 50W and may have a short life expectancy. I'm a great believer in getting on with building your own cab, you learn so much from it, not least your mistakes but if you want a reasonable result then it is good to listen to advice. You won't find good designs for this speaker because anyone who can design a speaker will know enough to choose something different. Speaker design is all in the maths and only the maths, you have to at least be able to drive the computer modelling programmes or understand the books/internet articles. if not then you might be better to use an existing design including using the drivers the designer has selected. Tell us why you have chosen this speaker to use and we might be able to offer more help. At least we will know where you are coming from and what you are trying to achieve.

I think the OP is wanting to carry as little as possible to the rehearsals. Rehearsals can be for different reasons, if you want to test out your stage sound then you have to take all the gear you will be using but if you are just working on songs then I'm a real believer in keeping the volume down. You can just simply hear so much more and if that sounds 'wrong' whilst you are playing then it is probably because it is wrong, as someone has said. Because our hearing is logarithmic doubling the power only gives an extra 3dB of sound, noticeable but not dramatic. Ten times the power only gives 10dB which subjectively is twice as loud. A 200W amp is only twice as loud as a 20W amp. That's why you are getting so much variation in power suggested. If you are using 200W into halfway decent speakers at a rehearsal in a small to medium sized room then, unless it is turned right down you should be wearing ear defenders. There's something slightly mad about carrying in a huge amp and speakers if you have to turn it down or block it out provided you can afford an alternative.

We're ten a penny down here. If it's the D and G strings giving you trouble on your bass then get new strings and then check the pickups are well away from the strings, that evened out the tone for me. Apart from that get playing, there are loads of open mic's in Taunton and around. Check the boards in Westside Music and the ads in Lemonrock.com. My band Wet Playtime play in the White Hart in Taunton sometimes.

It does depend upon so much but it is surprising what you can get away with. Just for fun I tried practising with our insane teenage drummer with a 20W practice amp going out through a fairly decent 1x12. by turning the bass down a few dB and boosting the mids it was perfectly audible and cutting the bass was probably an advantage in a small room. This set up would achieve 110dB at 1m. (that's peak of course) Without checking drums chuck out about 100dB at the same distance so it should be up about there in terms of volume, and it was. Nowadays i use a Harke kickback10 (125W through a single 10" speaker) as my practice amp. No problems at all and the kickback feature means I hear more detail anyway.

Well it is an interesting choice of driver with High Q and high Vas it wants a big cab. Win ISD came up with 654l as a first suggestion! With a 100litre cab tuned to 40 Hz (10.2cm dia 7.81cm port) it shows a big peak in the bass at 100Hz (about 3dB) but quite wide and flat. Combined with this speaker's big midrange peak this is going to have an 'interesting' sound. You might like it.

It sounds like room resonance to me. This can be complex and I doubt anyone will help much without being there. You may well be better to keep away from the walls as each reflecting surface near the speaker will boost the bass by 3dB. If the room is small this will be impossible of course. Raising the speaker well off the floor may also help. Basically the room has a series of resonances (just like a bass string) a suspended floor will have a resonance but so will the air in the room. In fact it will have lots of resonances. If you play any of these notes you will excite the resonances. Just like a string however the room is resonant in certain places more than others only it is in three dimensions. Moving the amp around might help you find the least resonant spot in the room. You'll have to use trial and error. I practice in one particularly resonant room. I use my Hartke Kickback pointing straight at me and turn down. The resonance means everyone else hears only woolly bass but it is bearable, just. Good luck

The W Audio is lightweight. I've got a Peavey IPR1600 for our PA if you want a name brand and light weight then these are good and with a crossover for subs. The cheap PA amps are incredible value for money and I've never had any trouble from any of mine, even the Behringers which just work forever just like the others.

Speakers and cabs work together with the cab designed to match the speaker so most of the time you are better off replacing like with like. 8" is a nominal size most 8's are actually slightly bigger Eminence and Fanes are 8.25". Are you sure you don't just have an 8 with a generous sized frame? If you can't get a replacement then you can stick a piece of ply on the back of the baffle (screwed and glued) and mount the speaker inside the old cut out, you may need to enlarge this to fit the new speaker. Make sure whatever youdo is airtight and you should be ok.

You are using a Sansamp through the PA? If so the only real function of the cab(s) you are buying is for you and possibly the rest of the band to hear the bass. The audience will hear you through the PA. If you have decent monitors you don't need a bass amp at all strictly speaking. In fact the bass amp/speaker is your monitor. Why do you want a second cab? If the ratings are right (big if) then this one cab will go to just about 126dB (probably excursion limited at the very bottom end) more than enough to drown out the drums or to damage your hearing. Even with 40dB dynamic range you can maintain an average sound level of well over 100dB. One speaker will be more than enough and if you spend more on it because you are saving on a second cab you will be able to major on quality rather than quantity and have a better sound. This solves your car problem, you can take the girl and her boyfriend!

It's easier than it sounds, I'm working on it at the moment and i don't have a tab yet but basically it is almost all in E and has a series of riffs on the minor pentatonic all played at the bottom position. It also goes to C and B in a couple of places. This is definitely work in progress but it is something like. G|---------------------------------------------------------------------------| D|---2-2-0-----------------------------------------------------------------| A|------------2-2-0-------------------------------0-3-3-2-2--------------| E|----------------------3-3--3-00---0-0-2-3-----------------------------| Hope this helps. I'm learning a whole set for a new band at the moment but if I get time I'll put this up on UG. By the way Bamboo I'm looking at my Daphne Blue Jazz bass which is what made me click on this post. Snap

To lower the resistance you need less wire or thicker wire or a combination of both. Manufacturers use all sorts of methods and if you are a major manufacturer you can get all sorts of impedances made up. If you are a home builder then beware, Most manufacturers do their design work on 8ohm speakers and the magnet gap is designed to work with an 8 ohm coil. To make a 4 or 16 ohm option the coil is changed with the 4 ohm version shorter reducing the excursion the speaker can cope with before distorting. The 16 ohm coil is often longer giving more excursion but at the expense of having more of the coil outside the magnetic field reducing efficiency and decreasing the control the magnet has over the speakers movement. This doesn't have to happen but completely re-tooling is expensive and just changing the voice coil by adding or subtracting turns isn't. As BFM says you need to check before using a speaker in a design, the 4 ohm and 8 ohm models probably won't be the same.

[quote name='shizznit' timestamp='1326912854' post='1503719'] Okay...I'm fibbing a bit...I do disagree with one thing (sorry!). Having a speaker angled to improve bass projection simply doesn't happen. Bass works from the ground up because of acoustic resonance. That's why bass bins live on the floor and tops...well...live on top! Not once have I ever seen bass bins above or in line of the audience. [/quote] Because of the way we perceive sound most of what we hear as 'bass' is actually contained in the higher frequencies. We are so rubbish at hearing low frequencies and so good at hearing mid range that Lawrence is right, differences in tone are all in the mids. The information that makes say, picks sound different from fingers, Rotosounds different from flats and nearly all the differences you get from your touch on the strings are down what we hear of the higher harmonics. All speakers are directional at any frequency whose wavelength is shorter than the diameter. So bass players need to point their speakers at their ears just like other musicians.

just for balance I'm going to make the other argument. Because these are mass produced items they are often very good value for money. The 12" speaker is designed for bass frequencies so it is no more likely to fail with bass than a 12" unit in a bass cab at the same price point. In fact the bass unit is designed to crossover at 1.6-3KHz so in some ways it is a more specialist bass driver than the ones in bass cabs. Just like cheap bass cabs the excursion may be limited but not so in the better quality cabs. The biggest factor is the sound. PA cabs try to be neutral, flat frequency and low distortion. Some bass cabs do the same but some are deliberately coloured. You either like the coloured sound or not, it is a matter of taste. If you are using decent monitors then the chances are you also have a decent PA. If this can provide the bass that the audience hear then you don't need huge volume on stage to be picked up by the vocal mics. Having an angled cab pointed at your ears means you will hear yourself better too. It is win win. I've been amazed at the quality of cheap PA speakers. Recently I took apart one of the Maplin ones. There was a decent magnet on the bass driver, a proper dynamic horn driver, good quality crossover components and the plywood cab was well braced. It met the specs they gave as far as I could measure them.

Just bought a kickback 10 and so far I absolutely love it. I really like the sound it makes with my Fender Jazz. No problems matching my drummer for volume, it is tiny and the tone shaping is pretty intuitive amd gives a good range of sounds. Gives a nice acoustic bass sound in one position. The kickback feature means you really get to hear what you are playing which takes some getting used to. I've kept my Ashdown/custom 2x10 for bigger gigs but the Hartke has become the 'go to' amplification. The rest of the band like the bass sound too. A bass playing friend has gone out and bought the 112 after trying my 10.

Wellington Timber and Yandles of Martock both in Somerset.

I'd really advise any bass player to avoid 4 or 16 ohm drivers. Most of the available ones were designed as 8 ohm drivers and then offered as a service to customers as 4/16 by simply adding a different voice coil. Because the rest of the speaker was designed to work optimally with the 8 ohm coil they are usually not as good as the 8 ohm version. Guitarists get away with it because they are not so interested in the bottom octave (two if you include the one we have that they don't). Changing the coil also changes all the speakers parameters so they no longer match the box. Stick to the recommended drivers, they were chosen for a reason.

Hi Lawrence, don't know which bit of Devon your folks live in but if it is near Chard I'm happy to cut a few panels on the bench saw.

+ in goes to the pin on your jack input or the + on your big speaker, often but not always a red wire. - in goes to the sleeve or - on the big speaker. There should be a terminal marked + on your tweeter (sometimes marked with a red dot) and that goes to T+. For reasons which are a bit complex the tweeter can be out of phase with the woofer at crossover and can sound better with the terminals reversed. You either get a small peak of a small dip at the crossover point. I always listen to both configurations before deciding. So long as your crossover is filtering out the bass neither way will damage the amp or tweeter. In any case when you test always start at low volume until you know you haven't made a mistake. Good luck

second the www.Lemonrock.com link particularly if you end up in W. Dorset. It will link you into the pub bands down here.

Hi Lawrence, you've probably cut your speaker holes by now but if you are stuck with using a jigsaw then you need a blade which is ground so the teeth are wider than the rest of the blade rather than a cheapy where the teeth are just offset. T101B is good or a T101BR which cuts on the down stroke. If you have to cut smaller than 10" holes then you would be better with a T101A0. Set the blade speed fairly slow and take your time. Use a new blade, I find old ones wear more on one side than the other and they wander off true as a result. Interesting you have chosen a PA driver for bass with an essentially flat response. I have done the same and I'm not sure of the results. Having true bass is interesting in a gigging situation as room acoustics become quite important. I almost always end up rolling off the bass, sometimes quite a lot. The relative absence of peaks in the 2-3k range means that the cabs lack character a bit. The speakers do what it says on the tin but I wondered if I might have preferred some of the 'inaccuracies' of the Eminences and the made for bass Celestions to the clean sound I have. It's all down to taste and I'm looking forwards to seeing what you think.

This depends upon how much twiddling you want to do and which drivers you have. As Bill has pointed out it is probably more to do with implementation than any inherent problem with the piezos. Most piezos act like a leaky capacitor in terms of load so you can trim down the volume by putting a capacitor in series with them. Try a 2uF polyester and see what it does to the sound. Bigger if you want even more cut and smaller if it is too much.. the other problem I have had with Piezos is that they don't have a very flat response and some are better than others although they all look similar. A lot of the cheap ones only have much output above 4kHz which leaves an empty gap between them and the bass driver. As Bill has said you'd be better with something crossing over at 2kHz or even lower for bass. My experience is that even fairly cheap coil based tweeters sound better than nearly all piezos though the absolute need to have a crossover makes them much more expensive

If it is in your price bracket the AER amp one [url="http://basschat.co.uk/topic/157525-aer-amp-one-the-best-amp-i-have-bought-evar/"]http://basschat.co.uk/topic/157525-aer-amp-one-the-best-amp-i-have-bought-evar/[/url]

You can run submixes in though you will need to match them, they might need to go to a jack or a phono input (line input) if the output from the submixer isn't a balanced (XLR) output. You might like to also think of looking at a mixer which takes all of your inputs and just feed the stereo output to the Stagepas which will act as an amp. The Yamahas have a great sound if you can put up with the relatively low sound output.

Don't know if this might help, there are other related articles as well, though you might need to go via my profile page to track them all down [url="http://www.ultimate-guitar.com/columns/gear_maintenance/a_guide_to_live_sound_speakers_and_amps.html"]http://www.ultimate-guitar.com/columns/gear_maintenance/a_guide_to_live_sound_speakers_and_amps.html[/url]

If you are in a covers band playing pubs, like a clean sound, and storage is a problem then take a look at AER's amp one. It's a tiny combo and it achieves a remarkable sound by the equivalent of an optical illusion (auditory illusion?) It compresses the bass end of your signal to reduce the demands on it's little speaker. At the same time this makes the bass sound louder and more 'in your face'. Compression is why the ads on telly sound louder than the programs. It also cleans up your sound. Because of the way our brains and ears work we can't really hear that this isn't genuine loud bass. Honestly I wouldn't have said this until I heard these things at gigs but the little so and so's work really well and if you are the sort of player that just likes to plug in and play then they are unbelievable. You'll love them or hate them but you really should have a look.