Phil Starr

It's standard practice and you shouldn't really be doing anything else. the only problem is when a substantial part of your sound is coming from backline. Obviously if you have set up your bass amp on an open stage and you are forced into a corner at the next gig then cutting the boom on the PA won't alter the boom from your amp. If you are operating without back line then you lose that problem.

It's a good shout, you'll find that even the humble AKG D5 is just as good at feedback rejection as teh D7 and still sounds so much better than the SM58. It's like moving from a Morris Minor to a new VW Golf. The only word of warning is that for people playing instruments a super-cardioid like the AKG's demands really good discipline on the mic. Even slightly off axis and the sound fades away quite dramatically and you really need to 'eat the mic'. I found after a few gigs with my AKG's that I needed a cardioid mic and went for the Sennheiser E935. My duo partner uses a Shure Beta58. For singers who don't play instruments and hold the mic in their hands this shouldn't be an issue.

I use the Sansamp BDDI with my duo. Gives me a choice of three tones though I stick to one clean and one with a little drive. Previously I used a Zoom B1ON (now the B1 four) With a bit of fiddling around you can get pretty much any tone you want out of the Zoom but I prefer the three old fashioned stomp switches on the SansAmp, The Zoom is relegated to tuner nowadays but would be a backup if anything goes wrong with the BDDI. The SansAmp is also a bit magic

And just in case you don't think a magnet can't hold a Gnome captive. This is my magnetic tray doing the lifting

They probably wouldn't need to be that big either. Strangely I nearly ordered some last night to hold on a grille I'm fitting to my BC108 I'd just ordered a couple of bits from AliExpress including some threaded inserts for mounting the speakers and noticed the said magnets in the corner of the screen at a good price, but just as I clicked so too late. I'm sitting here with my Gnome in front of me, as you can see the feet are naturally dovetailed so flipping them over would be possible. Alternatively a bigger bolt head or a steel washer would bring the screw head up to a fraction below the feet so that a set of four neo button magnets would engae with the bolt head and it would stop an amp sliding around. Another option would be to embed a magnet into the feet to engage with magents embedded in the cab.-

You don't need to be too scared of technology but perhaps a little wary of advice on the internet You've ben using two Mackie subs plus two tops, presumably for quite a while with no problems but some people you've never met have told you they are unreliable. It would seem they are wrong about at least four speakers! I've heard the rumours too which usually go along the lines of 'get the old ones as they are more reliable'. I also know of several local bands still using their 20 year old Mackies. Think of it as being like cars, My two most problematic cars were Toyotas, an AVensis and a Yaris, my most reliable were Fiat Multiplas. I don't think Fiat are generally better than Toyota but failure rates are low and Iactually 89% plays 95% means it isn't hard to be apparently lucky or unlucky. My advice its to take advantage of the internet and buy a used Mackie cheaply because of the internet pile on. To answer your question however. These are active subs with volume controls, mis-matching isn't an issue really. Subs really don't have flat responses so there may be a mis-match there but I doubt you'll hear it and the auudience not at all.

Coincidentally I used my 8 with a TC Elf last night at rehearsal, I usually go straight to PA but I have a new drummer and we aren't locking in as well as Id like so I thought using back line would be more familiar than PA and monitors for him. The little 8 sounded really lovely straight out of the box and remarkably just like the PA sound. It kept up with the drummer nicely too. I had all the controls set flat and didn't need to adjust anything, I'd say its a good pairing.

I can't help myself, I looked at this and thought that you could print feet that would replace the rubber feet provided and also fit into the dovetail groove. I have to keep away from thoughts of 3d printing, the possibilities are endless.

Just buy ordinary round rainwater downpipe, it's a standard size of 68mm outside diameter and has to be a standard size to use all the fittings. I stick to this or 110mm pipe as they are going to be around for a very long time. I used to specify ready made ports but the availability changes all the time and it put people off building. It also comes in black

At the moment that's me. I put the band together with lots of help from the singer but I'm the one who pushed it over the line. I'm really not sure I know what I'm doing and it's all very cooperative. Organisation is very 'loose'. This is a covers band and everone is pretty experienced. We've set ourselves the target of getting 30+ songs up to gigging standard with 33songs on the initial set list. We're attempting to learn 8 songs for each rehearsal. Some are simple enough to learn quickly and some we've all played before, some a bit more tricky or only a couple of us know them and others are new to us all and need a bit more preparation so I've made sure we don't overload any one rehearsal by mixing the low hanging fruit with a couple of songs to work on. I send out the list of songs as early as possible to give people a chance to prep them at home, Rehearsal is for re-hearsing what you've practiced not for learning the arrangement or chord sequence. We've settled into a kind of routine, we start with a song we all know well as a warm up, Then run through the 8 msongs to see where we are with them, we'll play each song once or twice and move on if we get bogged down but it gives us an idea over which ones will need detailed work and which ones are working out of the box. We will also play through any songs we had concerns about from the week before, usually as part of the warm up. Then we take a break (there's a bar in the place we practice) and talk though which songs we want to work on. Second half we'll work on the things we've discussed. It sounds pretty workmanlike but we're all pretty sociable and there's lots of chat whilst we are setting up. I've been in quite a few covers bands, I think it's all in the preparation. Rehearsal time is precious particularly if you have a young family or are holding down a full time job. People need time to prepare so I'd expect a list of songs with keys and a few notes to go out at least a week before rehearsal. Ideally for a covers band you'd be clear of which version of a song you are covering with lyrics and a chord sheet. It's easy with a covers band as you have original recordings and I've sent out cassettes, CD's and now Spotify Playlists. There's no hope of learning My Way if everyone expects to do it their way, so it saves time to plump for one version and do that at the first run through. You can add your own touches once the basics of the song are secure. One band I was in started brilliantly. The band leader arranged for us to learn four songs a week for 3 months. We had the full list up front in the order we were to learn them. Three weeks in we were running through four songs for the third time and used these to warm up. The songs from the previous week we'd fix any issues and work out starts and ends and then address this weeks new songs. A gig had been booked at the end of the 12 week cycle so nobody messed around. It's kind of the pattern I'm repeating with my new band, we took the decision to attempt 8 songs collectively given that we all knew some of the material and were experienced enough to find Eight songs manageable. Plus 12 rehearsals would have been excessive with our other commitments. A third band was an established band, I was expected to learn 30 songs , contacted them when I was ready , one run through and we gigged a week later. We only rehearsed when we added new songs and you were expected to get it right. I loved that.

Hi Al, I would go back to @EBS_freak's in ears bible. All of the analogue vs digital radio connection issues are discussed there. The problem with analogue is the companders. Poor quality UHF systems degrade the sound quality so that is the problem rather than latency.

Just use white woodworking glue (PVA) There are all sorts of additives they use to make it waterproof or quick setting but it is always stronger than the wood so it's not something to obsess over. Probably best to check the 'open' time which is usually 1-4hours in which time you can pull the cab apart if you've made a mistake but most of the brands will be fine. Once it is glued the bond will go on curing so it will get stronger over the next 24-48 hours. You can handle and even finish the cab but don't try standing on it during this time.

I’m a little puzzled as to how you experiment with braces once the cab is glued up, or are you just attaching the baffle with screws until you are ready to finalise the build? You caught me Because I am always tinkering, and these are always prototypes I always screw the baffle on so I can remove it to make modifications. You can fit side to side braces through the speaker cutout.

The trick the old music shops used to smarten up old gear was WD40, I've tried it on black vinyl and it does kind of work but I suspect it's more of a quick fix rather than a deep clean. I'd be trying out any solvents on a bit of the cab that didn't show however, most plastics are going to be Ok with most solvents but with older gear you don't really know what they've used. Theirs a hierarchy of solvents that retarers try working up from distilled water to soapy water, detergent , methylated spirits, isopropyl (rubbing) alcohol and so on, Working on tiny areas with a cotton bud is good as you can see the dirt on the bud and make sure the fabric isn't being damaged. Once you are confident you can use the product you've settled on to clean the reat of the cab. Beware of too much water, old cabs might be made of chipboard or MDF both of which will swell and break down if they get wet, old vinyl won't be completely waterproof. Whisking up soapy water and just using foam is a thing and I've found 1001 Carpet Cleaner works well. Start slowly and take care, most gunk comes off in the end without using anything special. good Luck

Did you mean maximum? I don't think that there is any magic about speaker protection. Excluding manufacturing faults, which thankfully seem to be very rare, there are only two ways in whicvh a drive unit will fail. Over excursion leading to mechanical failure and over heating. There is just one complication, if the coil spends time outside the magnetic gap then it can't dissipate heat into the magnet so that there can be a special situation where over excursion and heating combine, but all of this is very predictable. For years folklore or perhaps more politely 'rule of thumb' has allowed musicians to match speakers and amps. In the 60's most of us would allow for speakers to have twice the power rating of an amp if we wanted reliability. As high temperature materials were introduced most of us now would now expect to be able to use double that power and match the amp and speaker power. In PA however well trained engineers have pretty much always gone for amps that were twice the power of the speakers. That way they could manage the peak excursion and overheating issues because they had a basic understanding of the duty cycles and frequencies they were pushing into the speakers to get extra peak sound output without distortion from the amps. It all depended upon skill levels and experience but the advent of active speakers and now DSP has brought that to all of us. As @Stub Mandrel has said we can predict the heating/cooling of any part of the speaker from the testing done during the design phase and knowledge of the power going from the amp and the ambient temperature. You can also predict the position/excursion of the coil from knowledge of the frequency and power level , that's what the speaker modelling software does to predict frequency response. Temperature rise and excursion are entierly predictable for any given speaker. With the amp and speaker built into the box and DSP 'knowing' power and frequency levels you can afford to use higher power amps to get higher sound levels with the DSP taking sure to dynamically limit the power if things go outside of the parameters of the drive units. DSP is doing what the sound engineers were doing in big professional PA's for decades past, and class D amps are so cheap that putting big amps in small speakers is cheaper than building 5 different PA amps for every different speaker model. At the moment I'll guess that there are no sensors for ambient temperature in most base level systems used by semi pro bands. From the advertising I don't think RCF for exampe do this. What they do have however is a proxy for ambient temperature: the amplifier monitors it's own temperature as there is overheating protection built into the amp. If the ambient temperature rises the cooling on the amp is challenged and the temperature there will rise in proportion to the rise in the voice coil again this is all predictable. Obviously a sensor on the speaker itself would give an extra layer of protection. I found it really interesting to know which amp modules were being used inside these boxes and it's fairly easy to track the design decisions being made generally from these videos. I think it is fabulous that we can buy speakers that manage themselves in ways that allow bands to use more of the available output of the drive units. This sort of thing is already starting to spread to budget cabs and I suspect it will be moving to bass guitar combo's fairly soon.

The latest iteration of the RCF 9 series are already using dynamic management of excursion and I think it will rapidly become standard to use extremely high power amps across the range with Dsp controlled management of the amp to allow best performance of the drivers but keeping well within their performance envelope for increased reliability in the face of abuse from their owners

Essentially any extra bracing is good, the downside is extra weight and more work to do. There is always going to be a point where extra bracing becomes silly and you might even have to increase the volume of the cab to accommodate it for very little and inaudible changes in the sound. You can see that @stevie and I take different positions where I am more minimalist. If I were building cabs commercially and had access to CNC cutting I'd probably go the way of the LFSys cabs and for FRFR cabs it's worth going the extra distance. My designs are intended to be as easy as possible, I build and trial all the designs and if there are no problems I publish them. In the case of the 8" cab the original was built for someone else and out of 18mm ply to match an existing cab. It needed no additional bracing. I re-designed the cab to make it fit more easily onto a sheet of ply and used 12mm ply because people here wanted some weight saving. The only serious panel resonance was solved by the brace in the picture and that is the cab I use so I'm happy to recommend it. I want people to build the cabs so I deliberately keep it 'easy build' which means as simple as possible. Where we agree is that you should build the cab and try it, with or without the recommended brace. the cab is then customisable and it's good fun to try different bracing and stuffing. When I've done this in the past I've usually ended up removing the wadding except for the rear panel because I prefer the sound. I've seen how iterative your method is with the guitar builds so I know you are probably going to do this anyway Maybe some printed braces are in order?

Yes, that's what I thought. Lot's of details about which amplifier modules were being used and some about the drivers installed too. I started watching over a coffee break and ended up watching it through. He's not shy of saying where measurements disagree with manufacturers specs either. It's good to be sceptical but cynicism can't replace an open mind

Hi Rob, You don't need cross bracing for the cab to work and many commercial cabs don't trouble themselves with it. The point of cross bracing is that linking opposite panels stiffens them both. as pressure changes in the cabs it pushes or pulls the panels and at certain frequencies (dependant upon the size of the panels, stiffness and their mass) they will resonate. Since the panels push out at the same time the forces cancel so the movement is damped. Putting the brace dead central risks creating a node and simply doubling the frequency of the panel's resonance so dead centre isn't great. Even slightlyoff centre though and you are good. The biggest panels are the most resonant, as smaller is also stiffer. Usually bracing front to back is difficult in a small cab as the speaker is in the way. If you are limited to a single brace then side to side is a good compromise. The two braces in my photo were my best guess for damping. I dropped the top to bottom brace later as it wasn't achieving anything. I don't spend hours on bracing. My simple method is to feel for resonances with my finger tips whilst feeding sine waves from a signal generator., sweeping up and down the frequencies. Putting the brace(s) where they do most good. a single side to side brace worked well and the cab is really quite well behaved. I'm pretty much agnostic on wadding. It's a really complex issue with lot's of theories but little proof. It definitely changes things in the cab and resonances are reduced but it's really hard to say that there is a working predictive model. I'd say cover the rear panel with some decently heavy felt stuck to the back panel with contact adhesive. Staples alone always work loose IME. If you want to go further then you can treat opposite panels or even cover them all. If you go for the white polyester wadding then make sure it can't move around in the cab and keep it well away from the ports.

The dimensions at the start would work but I'd tune slightly lower for this driver Two drainpipe ports of 18cm each would be a better tuning and what I was using in the computer model above. You can get a slighly better response with bigger ports but the port is then longer than the cab is deep and would need to be removed, probably bottom venting. At anything below 200W you wouldn't have problems anyway. In the end I used this cab for quite a while with one of my bands and had no problems with wind noise from the ports at gigs despite playing with one of my loudest drummers (David you know who you are ). Like any ported cab using a highpass filter helps power handling and chuffing a lot as well as cleaning up your sound. It might be worth having a quick look at this thread. Although this is designed as a 10" cab with a tweeter/horn the basic cab is the same except for the front panel and a bit of extra bracing. There are proper drawings in the first post

As it happens I had the details with the Faital saved from a previous project. With 130W which is the typical mini-amp output into 8 ohms it looks like this. Ideally the Faital would be better in a bigger cab (better in terms of more bass and a flatter response) There's a 2db peak at 120Hz which is typical of many commercial cabs, but that's not awful; it will sound quite warm and bass heavy without eq . My original driver did much the same and so did the Beyma 12CMV2 It's really quite a good match. The biggest problem is that you need quite a big port for a small box to avoid turbulence in the port but if you limit it to 150W that shouldn't be a big issue

Just thought other people might like watching this. The auto translation is hilariously out in places but you can easily follow so I guess it is functional. The opinions may be surprising but evidence is given so it is genuine food for thought and for UK purchasers might point you in new directions. Who would feature in your top 12?

Those drivers you've used are pretty formidable Bill. Proper professional drivers and good ones at that. Stimulated by your designs I've been browsing the Celestion catalogue and they seem to have rationalised their cheaper offerings a little and to be moving upmarket, apart from their guitar speakers which has long been a speciality. I guess moving upmarket makes a lot of sense when you are manufacturing in a high cost environment like the UK or US.

I think the LFSys convention is that smaller dia speakers have shorter names. Spa is still free but once that is used there is nowhere to go

I can't help but think that you must be too loud. You don't need a sound level meter you can get free apps for your phone which will do a simple measurement. All you need to be able to do is to match the output of your drummer. Who may be too loud of course. At rehearsal you should be way below gig levels It's a problem with a lot of inexperienced bands, rehearsal is as often about getting out and making as much noise as possible rather than working on learning or improving new material. Bands playing flat out will damage your hearing. Measurements at Glastonbury showed Drummers experiencing 103db and most of the band 100db average levels. That's way above the safe levels where you would be wearing protective gear in an industrial site. You'll suffer permanent hearing damage in less than 15 mins at this level. Think about wearing in ears as soon as possible. They cut external noise by maybe 20db depending upon fit and when you get the mix right you'll hear everything better. It may be that your problem hearing yourself is that your hearing has been damaged at rehearsal. Hearing your self isn't just about volume, it is also about direction and frequency. Firsly make sure none of the guitar amps are pointing at you. They are very directional and should be pointing at the guitarists ears, usually they are pointed at the back of their legs or at some other band member who doesn't need that much guitar. Secondly point your own amp at your own ears. Speakers are very directional, like a torch beam so standing off axis is standing out of the beam. Secondly the frequencies you need most are the mids boost these. Most amps have artificial boost of the bass and treble to make them sound better at low volumes in the showroom. Cutting the bass also lets you use more volume as the bass is soaking up the power and moving the speakers into distortion. Cut the bass and treble. Mainly though get the others to turn down and the drummer to back off too if they are too loud. My guess is that none of you can hear yourselves well and each of you is edging your volume up to emerge from the overwhelming noise level. Basically you are all fighting a volume war. Our ears aren't designed to work at the volume of a Rumble at full volume and they don't hear well. Keep going and that will become permanent.