Phil Starr

looking good, have you braced by the horn/port/speaker on the baffle? It's a real weak spot and we had real problems taming a resonance there. The fix was a brace across between the bass driver and the port/horn and a similar one across the rear panel with a third brace connecting them front to back. I just used the same material I had for the rest of the cab so you should be able to use any offcuts for that.

There's not much in a crossover which will cause crackling, as Bill said the bulb usually either works or it doesn't. I'd be checking leads first and trying to see if I get the same crackle with a different bass amp and leads. Good luck, intermittent faults are always a bother to find. Ooh, I'm a supporting member, that's new.

Or you could try the Zoom B1-four. Headphone output, amp and cab emulations drum tracks and fx, Stereo input for jamming along and loads of other stuff too. I run mine off batteries but it runs off a USB supply and has a dc input also. It's my go to practice machine and with the sims and fx built in you can sound great. if only I sounded like that live

Nothing wrong with you or WinISD. This was Stevie's design, I designed the basic 30l box for a 12" project and built the box untuned for Stevie to develop. Once the design was finalised it came back to me and i rebuilt it to the original design and added an extra brace. Before I did I ran it through WinISD and got the same result you did. First I know Stevie checks the tuning after building the cab. In practice the computer models only get you so close. Some of the data we get from manufacturers is only approximate, is hard to measure completely accurately and subject to manufacturing spread. There are also other factors like leakage in the cab and around the speaker that change the tuning (there's something called Ql that allows for that) but not mentioned in some of the simpler explanations. I don't know what Stevie's target tuning was but I do know he would have measured it after building the cab and tweaking the port to suit. It's all in his diary somewhere. Xmax is measured differently by manufacturers (not necessarily a fiddle) It's meant to tell you when the coil moves out of the magnetic field which extends beyond the magnet itself. Some use a distortion measurement to give Xmax as the sound measurably distorts when the coil moves too far. Others use a mathematical formula to calculate the size of the magnetic field but Celestion use the old fashioned worst case calculation of half the difference between the coil length and the magnet gap depth. They pretty much all say how they calculate Xmax so it's not a problem for us. The point is that the coil doesn't suddenly move out of the magnetic field and xmax tries to identify when it first starts to leave the magnets control. Eminence for example would say this speaker has an Xmax of around 5.5mm so we aren't too worried. The curve you have is the same shape for all speakers in a ported cab and pretty much none of them can handle the full thermally rated power without exceeding Xmax. That's right, none of them including all those expensive boutique wonders. So why won't this speaker blow and why aren't there thousands of broken bass speakers? The answer is that there isn't much fundamental coming out of the bass pickups, most of the energy is in the second harmonic and upwards, the pickups are well away from the centre of the strings where the fundamental is loudest. The bass is effectively rolled off by the positioning of the pickups and the position of the plucking hand. We are all familiar with the bridge pups having less bass than the neck pups. So build with confidence

Well I finally got through to Romford. There's been some movement and the Germans have finally passed the order to the German delivery company. By this time they of course are on the middle of catastrophic flooding and the roads are blocked so I think it's only fair to allow them a delay It looks like it has passed through and is finally being transferred to the UK couriers. The next step will happen when someone at Parcelforce scans the barcode. I chatted briefly to the guy at the other end. He's actually serving in the shop and they only answer the 'phone when they don't have customers. It must be a thankless task too, if everyone has had the same problems I've experienced. In the end I made over 25 calls stretching over several days. Most of these calls ended up being cut off after being told to hang on "your call is important to us". Emails and other messages are not responded to and the ring back service is not working at all. Music Store the German company are having problems with their couriers and their IT and although i can accept I'm unlucky there are obviously hundreds of dissatisfied customers in the UK. That's a lot of bad luck. I've saved about £60 in buying their own brand lights. It's probably taken half a day's work to get the two failed deliveries to work and I don't think one of the deliveries would have come through at all without my intervention, at no stage have I really known what is going on and their emails and phone answers have proved to be inaccurate. If anything goes wrong with the lights then I suspect I'm in for another world of pain. If i'd known in advance I'd have gone for the best UK supplier, it's not worth that time to save £60. I'd recommend avoiding them until they sort out couriers, IT and some sort of UK call centre or at least additional facilities at the Romford Store. I'm sure Brexit and Covid haven't helped but it's not a professional service at the moment. If anything does go wrong you don't want a contract with a company who don't respond to emails, answer the phone or communicate the facts accurately. I'll let you all know if the stuff arrives

Well done, it's always rewarding to see a project carried through, I hope you have many happy hours and hopefully a few gigs with your speaker.

Yeah Markbass aren't very supportive for users in contrast with Ashdown for example. My Tube needs a repair (I dropped it so not their fault) and they aren't forthcoming with a schematic, extracting any information from them is like pulling teeth.

I have the MB Tube 500, the 'tube' inside is a miniature tube soldered directly into the circuit board, there doesn't seem to be any special heatsinking or dispersal measures employed other than the normal fan so I suspect there isn't a lot of heat produced by the tube.. I haven't had the chance to compare it directly with the LMIII though so there may be differences I'm unaware of. You'll have the chance to see if there are any practical modifications when you take the old amp out. Obviously if there are any vents in the casings they need to be unobstructed when fitted in your combo, so if you find any extra venting in the case you will need to ensure airflow through them. I suspect you won't. Why not contact Mark Bass and ask them?

Good advice, if you like the sound and just want more then using the same speaker is the way to go. Anything else and you are back to having to audition it. Of course you may not need a second speaker.

As I say there are a lot of amps around at the moment that are 500w into 4ohms 300 into 8ohms and Ashdown amps do this too. The power stage is fairly standard across a lot of amps just as a lot of car manufacturers share engines across different makes. It doesn't make sense for everyone to repeat the same design over and again and they all use the same chips anyway. This also makes a lot of sense as the speakers generally will only handle around the 300W mark. To be honest 300W into a fairly ordinary modern 15 is likely to give you a sound output of maybe 120-125db which should be easily enough to match the drums and more than enough to permanently damage your hearing. The other thing is that this is a new band and a chance to agree in advance that you won't be fighting a volume war. If you aren't filling the room with a 1x15/300W then it would be much better to turn up the PA than try to do it from behind the singer and the vocal mics.

I use old duvets as my source of polyester wadding. I'm also currently eyeing up a memory foam mattress topper, probably not what I want but I hate wasting anything. If you want the old fashioned felt most carpet warehouses (not some of the big sheds though) still provide it and will sell you a metre. They also will also have cardboard tubes the perfect size for speaker ports which are used to wrap carpet around.

I'm now having real trouble contacting the Romford people on the phone. I've rung several times waiting an average 10 minutes at a time. Don't bother with their frequently offered 'press one if you want us to call you back' they won't. Offers of "I'll chase it and email you" aren't any better, they won't do that either. I've tried their social media, it's full of similar complaints.

You say the South East, Andertons have their shop in Guildford if that is near you then you could scratch that itch by going and trying both.

I think Real Electronics is your only current authorised option Real Electronics | Manufacturers

not at all though it will change the sound balance. In this design there is no low pass filter on the bass units. Stevie took advantage of the natural roll off of the 10" Pulse and designed the crossover to bring the horn in to take over the frequencies that the bass units don't create. The shape of the frequency responses for two identical speakers are going to be the same within manufacturing limits but you are going to get far more of those frequencies. Somebody out in the audience will hear a bass heavy sound but for you this will be countered by the fact you have raised the horn to nearer ear level so it may still sound very good to you. The horn driver will still be seeing the same voltage being produced by your amp so will still be protected by the crossover.

Hi Roger, my experience with them continues to be very poor and a second consignment has gone astray. I wouldn't have used them but I wanted some matching LED bars and had ordered their own brand so was stuck with them. I don't think they are dishonest but just a complete shambles, I don't think their software in different department talks to each other as I keep getting contradictory emails. Persevere and your stuff will come through. good luck, I hope you aren't in a hurry.

Just looking at this I think you've had some good advice. One of your queries was about power. Most of the amps have power sections that use basically similar or identical electronics. There are a lot that do 300W into 8ohms and 500W into 4ohms. Frankly this is enough for anyone and conveniently matches the power handling of a single 8ohm cab, and two cabs give four ohms so you still have the power of the amp and speakers pretty much where you want. With so much choice at the 300/500W range you may as well start looking there. I notice there is a fairly pristine Ashdown Rootmaster in the for sale ads here. Buying used means you can get most or all of your money back if you change your mind. The outlier amongst what you've been recommended is the Bugera which uses a bridged version of the Behringer power amps for the output and puts out a genuine 800W. I've only heard positive rsponses from people who own this amp. Ashdown are a great company, they are British and they take after sales really seriously often repairing gear long after their legal guarantees run out and always willing to offer advice, often in these forums. Hats off to @Ashdown Engineering The thing is with such a wide range of choices you really need to start testing things out because they will all do the job and the difference is in the sound. No amount of internet advice will help you there. In the end after buying a MarkBass and trying a range of others I bought a Peavey Minimax and just love the sound straight out of the box. It looks however like you are a combo man so try those first. It's hard to go wrong really so choose on sound and enjoy your new band.

The Saga continues, the lighting bars that they eventually delivered were excellent and I'd only ordered one of each in case I had to return anything. The stuff had arrived in the end, the staff in Romford helpful so I ordered two more..... I waited several days and no confirmation email, then one saying the stuff had been dispatched and was due to arrive that day. Nothing arrived and the next day an email acknowledging my order but indicating the stuff had not been dispatched but was in stock. Then a couple of days later an email from the German courier (in German) saying they had been told of the delivery but no goods had arrived from DV247. I gave it 3 days then rung today, Romford helpful as usual and said they would chase and email me when they had news. It seems as if their internal communications have just not been fully integrated. I'm getting different communications from different parts of DV247 which just contradict each other. I want the lights to integrate with each other and I'm not in a hurry so i'll see this through but i just wouldn't order anything i wanted in a hurry. The lights are £25 a light cheaper than anywhere else so I'm saving £100 and that's worth a bit of chasing but wtf? Sometimes you are just unlucky but this is twice now, and I wonder if the orders would arrive at all without some chasing and the UK base to help.

The advantage of a DIY cab is that you don't 'have' to do anything so if wht you've done works in holding the grille secure and no rattles then it's fine. It looks from your pictures as if you opted for the folded grille. that will give it more rigidity which will help.

Yep 13.5mm should be fine. I'd probably make up a 'frame' of battens all the way round the circumference of the baffle, fixed in and then screw the grille to that but anything that will hold the grille firmly enough to prevent rattles is good enough.

I can't see anyone who lives in Evercreech going alcohol free, well not the people i know

I use ER20's and they are the only ones that give a decent seal for me whilst allowing enough through to let me hear the rest of the band. They are uncomfortable but my hearing is going and I have tinnitus which is more of a problem than a couple of hours minor discomfort. To be fair you did say you'd go custom if you have to. The other alternative is to go in-ears. it's not quite as simple as that sounds and you still have the problem of finding something to fit but it has huge advantages. The trouble with ear defenders is that if you do get a seal they cut out all the good stuff too, the bit's you need to hear of your band and that is as frustrating as having something uncomfortable in your ears or things that fall out and need constant fiddling with to be effective. The Leights look interesting and I'm going to try them but strictly for when I'm using power tools or mowing the lawn. I've just gone down the in-ears route and it's a revelation. I've spent hours trying to get a good seal on the earphones trying dozens of different earbuds and three different in ears. Once you get that fit the sound levels fall as all the background noise is blocked and the bass leaps forward. You even have a volume control on the drums. Everyone's ears are different and they change as you get older. It's going to take a lot of trial and error to get the plugs for you. too loose and they are useless, too tight and they will be uncomfortable and then you are asking them to cut out just enough noise for you to hear the band but enough to save your hearing. You are asking for a lot from a simple plug.

A clapping noise? That's new. It could be the end of the coil hitting the rear of the magnet or the cone meeting the grille if that has been distorted but that is usually described as a farting noise. Turning the bass control down ought to reduce/remove the problem by limiting excursion but less bass could reduce other possible causes too. It could be something loose in the cab. Check the speaker is fully tightened down and the grille is firmly attached and have a look at the internal leads to the speaker, if they are loose they can end up slapping against the cone which makes an alarming noise. It could also be a loose panel in the cab so check everything is as it should be. The other possibility I can think of is something on the cone that has become un-glued like the dome shaped dust cone, though that tends to be a buzz rather than a clap.

How loud are your gigs! I think you've outlined all the main issues bar one, how would it sound and will it be a sound you like. You really need to try the cabs if you can, with and without your own cab. If you just want more of the same sound another 2x10 would make more sense and the safe choice would be to wait until one comes up. The 4x10 should be more than loud enough on it's own and you might well end up using that as your go to speaker. The 15 will probably change the sound more than the 4x10 and be louder. only you can decide if the extra portability is worth the extra money. Try them out if you possibly can.