Phil Starr

Hi Smanth, with that cab I'd probably get up fairly close to one of the drivers only, rather than move out further and risk comb filtering between the different drivers. You'' also cut out other sounds like anything from the drums from feeding into the mic in a live situation. Apart from that I'd do it by ear, wearing headphones and listening to the changes as I moved the mic away from the centre of the cone towards the outside a small step at a time to find the sweet spot. Then measure the distance so you can find it again I'd only be mic'ing live if I particularly loved the sound of the cab though and even in the studio I'd be mixing it with a DI feed if I miked up at all. There's no right or wrong but its a lot easier to add to a clean feed DI'd from the bass than to remove distortion and eq after the feed.

Just couldn't resist, Squier Anniversary. Never bought a new bass before

Welcome to Bass Chat

It’s the nature of BassChat that threads are often derailed and become rambling catch-alls for all those with related but different issues. The only exception that comes to mind is the ‘IEM Bible’ where @EBS_freak puts in a lot of work and wrote an extensive wiki. There are probably others but I’m not so addicted to BC that I know every nook here. This is @Pirellithecat thread and I’ll be coming here to see how he is getting on. It’s up to him how he does it and if anyone wants a different thread then go ahead and start one of your own. We are all just here for the craic in the end just friends talking 😀 If someone wants to write a wiki it would be a great addition to the PA sub-forum. I’d love to give it a go but it’s weeks of work and I have a bass to play.

It usually is the guitarist 😂😎😂

You have to say this is a failure of government. There should be laws to prevent the unwary being exploited and moral hazard for all those who mis-sell or mis-price goods. It is everywhere from the pricing of train tickets to the sale of insurance. Even the removal of VAT on women’s sanitary products was taken by companies as a dividend and no reduction at all was passed back to the customer. When regulation is seen as ‘red tape gone mad’ or the ‘nanny state’ then you can only expect to be exploited. I would love to live in @Dad3353 world but sadly increasing parts of the economy ae controlled by corporations where the shareholder is king and the customer is only there to be exploited. Mind you we choose the government.

Ok so you have some noise and the KZ’s are emphasising it. Let’s look at the noise, it’s coming from somewhere. I’m assuming you have more than just the bass coming through your in ears? Try tuning off each active channel on the mixer. The noise could be from anything from a dicky lead to a broken amp but fx pedals are often a nightmare noise source. Just find which channels are noisy first. In the meantime just try rolling off the treble a bit in your monitor feed if you prefer the KZ’s. You don’t need the hyper real sound and nothing above 10khz is going to matter as a musician.

You will struggle to get something all singing and dancing at that price. Bass is quite demanding of speakers and high quality at high volume is always going to come with a cost. You are probably going to have to compromise a bit. I’ve successfully used an RCF ART310 but I’m not looking for huge volumes and I roll off the bass so it is less demanding of the speakers. Bass goes through the PA and of course the lower frequencies come back from them onto the stage anyway so rolling off the bass is necessary anyway. If you can compromise on volume Then you could pick up something like that used but within your budget.

Amps don’t really need ‘servicing’ at all. There aren’t any moving parts or any components that need routine replacement. The idea of a service comes from machines which wore at a known rate which would need regular checking to see that they were wearing at the expected rate and parts replaced at regular intervals. Parts in an amp all have known rates of aging but they usually last decades. The only exception to this is a valve/ tube which decay slightly quicker than the other components and can be expected to need replacement. If you were a touring band you’d probably get the valve amps checked regularly. Even so a pre amp valve like the ECC83 often lasts decades. I’ve got a valve radio from the 50’s still working with the original valves. Power amp valves run hotter and last less well but even so can give years of life.. The only thing that might make sense are regular safety checks. PAT testing in the UK, maybe blowing out the dust and cobwebs every 5-10 years if you are an obsessive. The thing is that components have a half life, a very few will fail in the first year some might last a century but it will be decades before most of them fail and you can’t really predict which resistor or capacitor will go first or indeed if it might be a bit of plastic insulation on a wire that goes first. There is no point in replacing everything just to be safe and it would cost a lot more than a new amp to do so. The other thing is that cleaning the pots (volume and tone controls) is more likely to shorten their lives so regular tinkering IMO is more likely to shorten the life of a modern amp. Save your money and don’t let some monkey poke around in your precious bits😆

Let me know how you get on. The KZ’s won’t create any noise but it may emphasise something which you barely notice otherwise.

It’s difficult to be certain of these things over the net without being abl to see or hear what is going on. First check your batteries. I’ve had the odd noise with dying batteries. Also be aware that the KZ’s have a pretty extreme frequency response boosting bass and treble a lot. I’ve struggled with the bass tone generally with them and booting the treble will emphasise certain types of noise. Also look at your leads, you’ll have wiggled them when swapping the D770’s in, duff leads can be intermittent.

Just use the main output sockets on the back of the mixer. I'm not sure if this will disconnect the internal power amps or not but it shouldn't pose a problem.

First of all it sounds probable that the coil is gone but you can check your 15. Get a large glass or a bowl so you can push the cone in gently without any sideways pressure. If you hear scratching as you push the cone then the coil is rubbing against the side of the magnet and your speaker is effectively dead. Double check your cone though, the glue line sometimes breaks where the cone joins the corrugated edge, at the point where the voice coil joins the cone or even the dust cap comes away. You can usually repair this with some latex based glue. As this is a Hartke is could be the aluminium centre coming away (less likely) so I'd look there too. Any replacement speaker is not going to sound like the Hartke original, even if they are a good match for the cab the midrange which gives most of the character will be entirely different, maybe better or worse but certainly different. If only a Hartke will do then you need to look for a used Hartke of the same vintage. A replacement cab of that age will probably be less than the cost of a replacement driver.

Not daft but maybe over-thinking it. Pre amp describes just about anything that deals with low level signals, they don't have to be something that changes or colours your signal and they don't even have to have any gain, they may just be matching impedances or buffering a signal to stop it affecting other parts of the circuit. Unless you intend designing your own electronics you don't need to know any of this Just be confident that the electronics in your interface are as clean sounding as they can be.

Hi Smanth, don't panic, whatever it is can be sorted. You can start by blocking those holes, and maybe sticking down the loose vinyl at the back of the cab. Just find some screws the right size to screw in the holes, you don't want to make them any bigger. You could even cut a couple of strips of wood the size of the old plastic strips and screw them on temporarily. It may not fix the problem but you have eliminated one possible cause. I have a minor problem here so I'll only dip in rarely for the next week or so.

Hi again You've kind of asked several questions here, I don't have a lot of time so I'll just answer the one in this bit of your post. So first of all you are spot on, basically you get twice the power through 4ohms and half the power moving back up to eight ohms . But that's theoretical, the theory works when the amp is running with the volume down but when you turn up full practical limits come in and it's almost always slightly less than double. 125W is as good a guesstimate as any. The second bit is about how much power the speaker is safe with. Matching the amp to the cab (there is a third question about matching two speakers but I'll ignore that for now) It's slightly complex because the power rating of a speaker is measured very differently to the way an amps power is measured. For the amp you are just measuring it's electrical output. If you know the Volts and Ohms you know the theoretical power and you just need to check that the amp can provide the current. Speakers are more complex, you can destroy them in two ways, pass too much power and the coil gets hotter and hotter and eventually blows. (heat causes other problems too but let's keep it simple). The second thing that can destroy a speaker is uncontrolled movement beyond the design limits of the speaker. The more power you apply from the amp the further the speaker cone and couil move, but this is also affected by frequency. The lower the note the more the speaker moves and a combination of excessive bass and power is what is more likely to cause failure by over-excursion than heat alone. It's that frequency element that makes it complex because: a.) nobody knows how you are going to eq or play your bass and b.) The cab plays a big part in controlling excursion so the same speaker may handle 300W in one cab and only 150W in a different cab. So, at the factory where they design and build drive units they test speakers by putting them in a standard box and by passing a standard signal through the amp for several hours until eventually they know how much power they can apply before the speaker fails. The standard AES test is for two hours and the standard signal is white noise (all the frequencies) but filtered to mimic the mix of frequencies in 'typical' music. The AES test says the speaker should be able to handle the power for two hours without failing. It's a good fair test and easy to do so you can compare speakers. Engineers and speaker designers can be pretty confident with this information but they knows that this is only half the story. Once the drive units leave the factory they cannot know what cabinet they are going into and what instrument they will be used for or how the musician will play, there are so many unknowns that no attempt is made to rate the speakers for use. So when you buy a 2x10 fitted with two Celestion speakers rated at 200W ea you will be told its a 400W cab. and samples of the speakers have been through the severest test possible of running for two hours at full power without harm. The reality though is that your 500W amp isn't going to overheat them. Music isn't continuous noise it has loud bits, quiet bits and times when you stop playing. Have a look on the back of any modern amp and it will give a figure for power consumption which is way below the maximum power of the amp. I've got the 200W Gnome in front of me and it says 60W power consumption. That breaks down to 10W of energy wasted heating the amp and 25% of the 200W going to the speakers on average when the amp is running flat out. If you keep the bass eq down and play 'normally' you can safely use a 1000W amp without your 400W speaker over-heating and some people actually do that. The problem is that you might like a bit of bass boost or you may add in all sorts of pedals and you still have the excursion limits of the speaker to worry about. There might be a frequency where each of those Celestions can only handle 25W each and your 400w cab is only a 50W cab at that point. So going back to your question, you could almost certainly use your 100W speaker with your 125W amp. 99% of the time if you use a 300W amp with a 300W speaker you'll never have a failure, you can probably risk going a lot further and use an amp that is double the power. People rarely turn their amps up full anyway and in reality your average power use will never reach 25% of full power. You don't need to be over protective but you do need to be aware of the over-excursion issue. If you are using a of of bass boost, slapping your bass without compression or increasing the frequencies below 100Hz in an unusual way and you hear unusual noises from your speakers at high volumes then you just might have a problem. I suppose I'm saying just be aware you are comparing apples with pears when looking at amp watts and speaker watts, six apples don't necessarily weigh the same as six pears

Hi Smanth Power is all about the transfer of energy the watt is a transfer at a rate of one joule per second. In electrical terms it's calculated by multiplying the voltage by the current. So for 100W you could have a power supply of 100V at 1A. For a 10v supply you'd need to drive 10A and for 1V supply you would need 100A. Your amplifier will be built with a power supply which has a fixed voltage which it simply can't go above and it will also have a current limit where it starts to overheat, the voltage will drop and eventually it will burn out (OK it won't as it will probably blow a fuse or trip something, but lets keep it simple) So the current is reduced as the resistance increases. If your amp is a 50V amp and your speaker is 8ohms you'll get 50/8=6.25 amps. 50Vx6.25A=312W If you use a 4ohm speaker you'll get 12.5A which would give you 624W and a 2ohm speaker 1248W and so on, but of course you won't get unlimited current so in the end the amps power supply will overheat and break down in some way (usually controlled ) This is why you see so many 300W into 8ohms and 500 into 4ohm put a amplifiers. It makes no economic sense to put a bigger power supply into a medium power amp when you could up the voltage a little and deliver that power to an eight or four ohm speaker. So the instantaneous peak is just advertising nonsense. You can measure the power supply voltage and you can measure the maximum current and that gives the power. The instantaneous power is just the real power multiplied by 2. Sometimes they give it away with an asterisk* sometimes they don't and even don't tell you they haven't ever measured it, because you can't measure a ghost! *calculated (as if multiplying a number by two is much of a calculation) There is a fiddle here which lets the advertisers get away with it which I'm happy to explain but it's to do with RMS voltages and I'll only answer if you ask So minimum load is 4ohms because any lower would draw too much current and overheat everything if you turn the volume up too high and the Speakon is only marked as an extra warning, it's written on the amp and in the manual too so you can't say you weren't warned.

That's almost a thread de-rail One of my pet hates. They are always the ones that suggest the songs with all the clever arrangements, never get on top of the tricky bits and then tell us it is more 'creative' to do our own version with just verse/chorus and an extended guitar solo over 32 bars of E7.

Genre often makes things more difficult too, I briefly played in a country band and thought foolishly 'all root-fifth and on the beat' Completely missed that this leaves nowhere to hide and the bass is prominent so you can't afford to be sloppy. Every genre has it's meme's and looks easy when someone else is playing.

I feel the pain, though as you both say it makes for a more interesting song but I curse when someone wants you to play one of these with a couple of days notice. One thing that always trips me is where there are maybe only two or three chords and in just one or two parts of the song where the chord sequence changes but the rhythm doesn't.

I guess it's personal to an extent but playing with three covers bands I learn a lot of songs, mostly at fairly short notice. With Christmas coming up I'm getting suggestions for songs we'll only play a couple of times a year and a lot of them are written by 'proper' musicians and have a lot of arrangement going on where they look superficially simple but have a lot going on musically. We've also had a run of illness and had to use a lot of deps so they prefer to do simpler songs for what are one off gigs for them. It's a given for me that I don't have notes in front of me when I play. More or less in order I find these make things more difficult Songs I've never heard, it's so much easier if it's a song you can hum along to. Complex arrangements. Rhythmic complexity (took ages to get the Steve Harris thing) Chord changes part way through a bar. Every verse is different Stops So what makes your heart sink when the singer says 'Let's learn three new songs for a one off gig'

It all sounds promising. Our '30l' cab is actually around that size, I prefer to be slightly over than under and I found with your speaker that going down to 30l and below was where the performance fell off sharply so 34l looks good. I did try 55hz tuning and thought it looked a little better but that to an extent is about taste. It's worth remembering that winISD is only as good as the data you enter and that the manufacturers specs are sometimes not entirely accurate. The program also makes some assumptions about things like leakage from the cab assuming Ql is around 7 for example. so calculated tuning is not always the same as the actual tuning. With drainpipe being so cheap I've often made up a number of ports so I can swap them around quickly and try different tunings. It's all about what sounds good as well and ideally you want an iterative process of designing and testing. Have a look at excursion and maximum power handling too once you have programmed in the tuning as this will change at 55Hz too. This is the point where it gets exciting

I've had a quick look and Bill is spot on 40l is about right for your speaker. Any smaller and you lose a lot of bass response which you will definitely hear in the result. This is the bass response of your Deltalite in a 25l cab in red. The green line is the Celestion Pulse in our 30l cab which has a fairly light neutral sounding bass. You can get that sort of response if you go to 35 litres with your driver and I think you'll prefer the extra bass. You'll get even more of you go up to 42l but i personally wouldn't go down to 25l with that driver, for me you'd be squeezing the life out of it

When I designed the first easy build cab I wanted it to be something that someone with minimal tools and experience could build on the kitchen table with the minimum frustration and the maximum chance of success. I wanted to use materials that are available not just in the UK but around the world and not likely to disappear. I've 50+ years of experience building cabs and access to my own well equipped workshop but I wanted something somebody could build with the tools I started out with: screwdriver, drill, and a couple of saws. Using screwed and glued battens makes it all a lot easier with no need to wait around for glue to dry, no fiddly clamping and very little chance of failure. Happily lot's of people have been encouraged to build their first cabs and are happy with the results

But if you have found the amp that get's the best out of your speakers you have to buy one for demonstrations, that makes it a business expense The colours match too!