Phil Starr

Thanks, I usually put the bass through the B1ON so volume shouldn't be a problem. Is this a thin sound through the supplied headphones or through an amp?

Anyone any experience with one of these? I'm thinking of buying one so I can do silent practice when I'm away from home, though of course I'll try it with the amps. Playability will be more important than the sound but obvoiusly a decent sound would be interesting too.What do you think, a worthwhile purchase?

The simple answer is yes, it makes a difference. We dicovered whilst developing our designs here that one big round port is the ideal. Tust to be clear you can tune the cab to the right frequency with pretty much any port so long as it is the right length. At low to medium sound levels there won't be any difference you'd hear. As the volume increases the air moves more quickly through the ports and turbulence occurs within the ports, effectively caused by the resistance to air flow at the port walls. The ratio of wall to cross sectional area is worse for a lot of smal ports than for one large one so you get more turbulence. This in turn causes port noises and some compression of the ports output. So, why did I leave the design as four small ports? The reason was ease of construction, it uses standard guttering downpipe and hole saws are readily available for this size pipe. It also allows front mounted ports with less weakening of the baffle. We had lots of debate about ports, more than almost anything else really. Mainly it revolved around how much output there would actually be and at what frequencies. The science tells you the port velocities but not how loud an actual bass will be at a gig. All I can say is that I've never heard problems in practice. All speaker design is a bit like wrestling a balloon, you squeeze a little more in one place and something else pops up elsewhere. For example the triangular corner ports in some Genzler designs are a really neat way of stiffening a cab and building within a budget but could be the worse design possible for this sort of port noise. I play with very little deep bass in my eq so it wouldn't be a problem for me, probably not for anyone but designers like to push the envelope.

Hi sorry I didn't get back to you with the port calculations, I was on holiday in Madrid Let us know how that works out. You are right about the stereo amp, as Bill was saying.

OK how old are the Deltalites? Are they marked as Deltalite 2510-II or just as Deltalite 2510? I've been trying to keep it simple because I think B.flat just wants to get on with something that sounds OK, to get the best out of what he has. To be honest Stevie I don't think the phase issues will necessarily be that serious as the OP isn't trying to get a cab with a flat full range response. As he has the gear all there and he can try it without any expense or speaker surgery he might as well try it. (for the OP the phase issues will result in a bumpy frequency response through the crossover range) The thing is it is difficult to say what the combination would sound like when we don't know what the 15 is. Unless the sensitivity is in the region of the 2x10 then driving them all in parallel might not work. There are still too many unknowns to be I do agree with Stevie that porting the cab will give some extra bass and may make the 2x10 more useable on its own. yes it'll be bass light but that may still be OK. If they are the older generation Deltalites then they should be fine, WinISD shows them as being flat +-1db down to 80Hz with the cab tuned to 60Hz The other issue is impedance, I'm assuming the Deltalites are 8ohms and so is the 15. That's not an issue with a stereo amp but a single amp would struggle to drive all three speakers. I'd suggest the OP try the cabs with his crossover as they are. If he likes the sound that's great. If he wants to port the cabs after that with a bit more detail we can calculate the ports for him.

Sorted

I haven't got time at the moment to optimise what you have but you might like to have a look at Eminences own designs for this speaker https://www.eminence.com/pdf/DeltaliteII_2510_cab.pdf If you scroll down you'll see their recommended cab for a bass 2x10. It's getting on for 85litres. There are loads of other designs too. Is this a cab you've built or have you installed the speakers in a commercial cab? They are perfectly decent speakers so if you are up for a bit of woodwork well worth building a suitable cab for.

If you want something really simple to use then this https://www.ajdesigner.com/speaker/ will design a vented box for you. It isn't very flexible however as it will simply calculate a single box size optimised to give the flattest response. This often means the box is impracticably large for bass guitar. What it will do is just tell you the port is too small. Win ISD that Bill is recommending is much more flexible, you can change the tuning and box sizes and it will show you how that affects the frequency response and it will allow you to make the ports any size you want too, recalculating the length to keep the same tuning. It will pay you to learn to drive this software if you want to do any serious speaker building or modification. As to the OP request, give us a lttle more detail. Why are you wanting to do this? What speaker are you using? what size is the box? How much power will you be putting into the speaker? It is unlikely that you'd get chuffing at low power but if you are trying to match a monstrous drummer with a single speaker....

Not just 'back in the day' try playing along with Rag'nBone Man's Human

Not disagreeing with any of the advice, but at the risk of trying to teach you to suck eggs... You absolutely need a crossover and if the subs are passive the one(s) in that won't do. The chain is mixer->crossover->amp-> speakers. though with your active speakers the amp is built in. Crossovers may be built into your tops subs or separate like the Behringer. Some mixers even have a crossover built in, not yours, it's the same one I use. The crossover for a sub will work somewhere in the 100-150Hz range. Irritatingly your iNuke has a crossover built in, but no sockets to connect it to your tops. Without the crossover your tops will have all the bass going through them and the subs as well, that means the bass potentially will overload them at high levels and the sound probably won't improve, it may even be worse with the subs in place. The simplest solution is to buy a standalone crossover like the Behringer. you could go for an amp like the Peavey IPR1600 which has a full crossover for the subs or the best solution buy an active sub with the crossover built in so you can feed one lead to the subs and then on to the tops, which cuts down the spaghetti on stage.

What Bill is saying makes a lot of sense but I'd add one caveat. The fan should be enough to keep the temperature within acceptable levels but it is possible that inside the amp there are cooling fins that need to be vertical to dissipate the heat into the air prior to the fan removing the hot air. Without having the amp on the bench I wouldn't be able to say if this is the case or not. This is only a problem if the amp is stressed and most amps would be fine. If you are operating the amp at high levels and it's in a hot room already then I'd be cautious, otherwise nothing to worry about. Won't an amp on it's side look more odd than a bit of overhang though?

I've neen following this thread with interest and not a little amusement. What a great question; is Tab[b] evil! [/b] Well what is going on in Syria,Myanmar and Yemen is evil. The jottings of a few musicians evil, you'd think so from a few comments here? I can understand people who read thinking (knowing really) that standard notation is better but I do wonder why they sometimes get upset about people learning/using tab. Is it because they see it as cheating, just too easy. Does it let too many people in? Like taxi drivers with the Knowledge resenting sat navs? In the end if you play in a band you need to have a way of communicating with other musicians, and once you can write stuff down you can communicate and share with the past and future. You do a lot of work, you can share. That's true of both systems of course. In the end most of us play with guitarists, we pretty much all understand tab, only a few readers around so inevitably tab is our default, and with a fretted instrument it is so easy, you can learn it in a few minutes. There are many hundreds of amateur/hobbyist/weekend warrior musicians and only a few who make a living from music. Should we shut them all out? All of us who just make music for the sheer joy of it? Let's not pretend, I'd love to be a reader, I'd be a better musician if I was, but I'd never get the shopping done put food on the table and get the washing up done if I took on serious music study. Tab lets me get by and I'm thankful for it, it has fewer shortcomings than I do as a bassist. Hang on though, if I spent less time on BC maybe I could learn to read, now there's a thought...........

This sort of discussion goes one of two ways usually. Somebody like the OP raises a question and a few people chip in with observations then the techies get involved and try and explain the observations. Sometimes they (we?) agree completely and sometimes they don't, differing on details or perhaps interpretation. Science will tell you a lot about what a particular speaker in a particular box will sound like but it has nothing to say about which sound you will prefer. What we all hope is that by sharing some of the technical stuff people learn a little about how the gear' we all use works and can use their understanding to shorten their search for their sound, and at the same time stops them wasting money because they can't see through the advertisers hype. If you re frame this thread someone is saying 'I think I can hear a difference between front ported and rear ported cabs' and is asking if there is any technical explanation. Bill has put up a graphic showing that bass at very low frequencies is radiated equally in all directions and you can verify this yourselves with any textbook or a quick search of the internet. Then both Bill and I have explained that for the most part ports are put on the rear because of space considerations in very small cabs and that in turn is down to the nature of the speakers used to drive the cabs. This is all down to something which I called damping and Bill called Q, the mathematical symbol for the damping of tuned systems. Well damped speaker cabs are usually powered by speakers with more powerful magnets and are built into smaller boxes, poorly damped speakers tend to be built into larger boxes which will have more space for the port to be on the front. Now the damping affects the frequency response at the bottom end in a predictable way. Poorly damped speakers have a typical bass boost around the 100Hz range that typically is described as 'punch' well damped speakers have the cone movement, well damped really, so they have a flatter response which even droops slightly if they are over-damped. So well damped speakers are less likely to have a bass hump and more likely to be in small cabs with the port at the back and under damped 'punchy' speakers are more likely to be bigger speakers and have front ports. But, you can design front ported speakers that are well damped and put the ports in the back of underdamped speakers. There may be a small correlation with what Ghost Bass is experiencing but the causal link is the damping of the speaker and as Alex has said his well damped drivers are going to have little in common with the Genz-Benz. Of course well damped and poorly damped are only the way we describe the Q of the speaker in words. You may prefer added punch in your speaker (I do) so an underdamped design may be what you are looking for, it may even sound more natural to you as most bass speakers are underdamped designs. So the advice is still the same, don't worry about the ports and use your ears.

I'm sorry but you probably have to start again. Obviously a 4ohm speaker is not what you need unless it is meant to be a single speaker solution. I'm worried about that 10 too. A single 10 unless it is something very special will struggle to handle enough bass to match a drummer. you've kind of gone from one extreme in the Ampeg cab to the other. You've gone for a 'matching' cab in the 15 but all that will really match is the appearance. That's probably important if you are playing functions fair enough but there are no guarantees that two speakers from the same manufacturer will match any better than those from two different manufacturers. For me the trick would be to find a nice light speaker that gives the sound you want and will be enough to use on it's own then add a second identical speaker for the times you need to do it all from the back line. That will give you the same sound but louder, anything else and you will get a different sound when you add the second cab. At the moment you might be able to get what you want from a couple of 12's or 15's. I'm not convinced a couple of 10's will be enough if you are used to the Ampeg and I've reservations about the 10 you have, unless it really is just a monitor and you are prepared to roll off the bass when using it on it's own. I quite like a single 10 with the bass rolled off when going through the PA but the rest of the band miss the deep bass on stage. I realise this doesn't sound helpful. I'm hoping you bought used and can sell the cabs for what you paid. Sell them and get two matching cabs. Two EBS 15's, if you love their sound, are going to be a lot less to carry than the Ampeg but there are plenty of others to choose from.

[quote name='Ghost_Bass' timestamp='1504719277' post='3366893'] Yes you're correct but i think there's even more to it than just that. With the port to the front it sounds more focused and punchy. The notes "breathe" more. The back ported cabs just throw me a wall of wooly bass that in some stages may become boomy. BTW, i use my cabs lifted to ear level and never in corners or backed against walls unless there's no other option available. [/quote] The trouble is you are comparing chalk and cheese. You aren't comparing speaker cabs with the same drivers in, they aren't the same shape, size and the ports are all different sizes and shapes. In addition unless you did your testing all in the same room with the speakers carefully placed at the same spot using the same bass and amp with the settings all identical it isn't really a fair test. Oh, and you'd have to put the speakers behind a screen and the assistant switching the speakers round wouldn't have to know which was which either, a double blind test. What I'm hearing is that you prefer some forward ported cabs to some rear ported cabs. You are probably right but that isn't necessarily about the port. Most of us prefer the look of a traditionally ported cab (me included) they just look right. The reasons for putting the port on the back are usually to do with the restricted size of modern cabs. As someone has said you can't put a big port on a small baffle. Small cabs are only really practical with speakers with more powerful magnets to get the damping and they have characteristically different frequency responses. Maybe you just like big old cabs or underdamped responses. Nothing wrong with that it's what made the bass sounds we've all loved for years. I guess the only reason for saying this is to help the next person looking to buy a cab. The advice is that you should try them out, see how they sound, don't worry about where the port is. Buy the one that sounds right. Always be sceptical of experts unless they offer evidence, which people have, but science does give you a way of deciding right from wrong and a lot of people here like the technical details. In this case the science is unequivocal, the placing of ports isn't going to make a difference unless someone has screwed up. There are better things to worry about, like the size of the ports.......

For me the answer is no, or at least not usually. The limiting factor for most pub bands is the ability of the sound engineer, and the time taken to set up. Keeping it simple is always a worthwhile thing to think about. Mostly the drums are too loud anyway unless you are lucky with your drummer. Acoustic drums sound really nice, poorly miked ones not so much. It's not really a case of shoving any old mic somewhere near the kick and automatically getting a good sound, it takes a lot of skill/experience. You really need to listen to your sound. does it need more drums? If not then why do it? Do you have someone out front mixing? If not you can't tweak the sound anyway so again why make it complex. Obviously if you are playing bigger venues you'll need PA support and a lot of bands like a bit of extra kick drum in the mix but it is horses for courses and I'd need a reason to start miking the drums. If you do then go on the internet and start researching, I quite like two overheads, have a look at the 'Glyn Johns' method.

https://www.youtube.com/watch?v=QeIxJzdPD0A

Your question doesn't make total sense. Which amp are you talking about? The output from a valve amp goes through a transformer which is designed to match the speakers. Depending upon the amp the output may be matched to 4,8 or 16 ohms or even all three. You may also have just a four ohm output with two sockets, plug in two 8ohm speakers into these two sockets and you have a 4ohm load. (so that's [b]either[/b] one 4ohm [b]or[/b] a pair of 8ohm speakers) You'll only get full output if your output and speaker impedances match. A fifty percent mismatch isn't going to break anything but will reduce the power available. You need to read the manual to check which situation you are dealing with.

[quote name='fftc' timestamp='1504425008' post='3364683'] What about side ported or bottom ported? [/quote]with side ported common sense works. it's no different from a rear ported cab. A bottom ported cab is going to hve some extra resistance imposed upon the port but the designer should have allowed for that in the design.I personally can't think o a commercial bass speaker with a bottom port.

the port only makes a sound around the tuning frequency. For most bass speakers that will be roughly 50Hz. The wavelengths down that low are roughly 6metres so moving the port 30cm round the back of the cab will make almost no difference to what you hear. Obviously if you were to jam the speaker hard against a wall and block the rear port then that would affect the output from the port but if it is more than the diameter of the port away from the wall you won't have a problem. You can use a rear ported cab with no worries

Are you listening for pleasure or trying to transcribe a bass part. If the latter then extra bass really won't help. Try rolling of the treble and mids, effectively this removes the other instruments/vocals a little and lets the bass through.

In a previous band we used a Behringer B205D on a mic stand or the drummer which he quite liked (bought it off me, so he must have done) I think he liked being independent of the main monitors.

I had the chance to try side fills for the first time this w/e. A couple of Wharfedale Titan 12A serving backline and keys with traditional floor monitors for the frontmen. I have to say the sound was great with vocals and keys really in focus over some noisy bass. No feedback issues on a biggish despite the vocalists using cardioid mics, can't weed them off their SM58's

[quote name='Gottastopbuyinggear' timestamp='1504094112' post='3362618'] By way of an update, we've gone for Yamaha DBR12's (based on reputation for reliability and the four year warranty) and a Soundcraft UI12 (based on having 8 mic preamps, should we need them, and ability to have up to four separate aux mixes). Not used in anger yet, though we have used for rehearsal and I found it really easy to get a good mix. So far no problems with the built in WiFi on the UI12, though I have also got it linked to a small WiFi router via ethernet cable. Still looking at new monitors - the Alto TS210 looks a likely candidate, although there are a lot of stories about the tweeters blowing on them. [/quote]I'm sure you'll get many years of great sound from them. If you don't blame the band One school of thought is to use the same speakers as your PA for monitors, then if one goes down on the PA you can swap them out. It's worth a thought if you can afford it. Having said that I like dedicated wedges with the controls available on the front. I bought a couple of cheap Behringer 1320's to try out and currently (two years later) they are still going strong and are my 'go-to' monitors, really clear but lacking in bass which is not a problem for vocal monitors of course.

[quote name='thepurpleblob' timestamp='1503737333' post='3360594'] ....and Noris, you *still* haven't linked us to her Facebook page [/quote] you need to be more enterprising, there's a link to the band's Facebook page in Norris's sig