LawrenceH

So that's where I'm at. Things still to do include getting the finish washers on exposed screws and adding feet to an extra side if I want to stack on the shorter dimension. I'll try and arrange it so that the feet of the top cab when stacking sit with the screws/washers of the lower cabs inside them to stop and chance of slipping. Similarly it'd be good to add something to secure the F1, and a tilt function. On the second cab I haven't got quite as far but I think that rather than screw the corners straight over the foam/vinyl I'll put in a nylon washer instead of the foam, 1mm thinner than the surrounding foam, so that it doesn't compress the vinyl quite so much on the corners but still holds it nice and tight. I may also get round to making a vinyl cover to help protect the speaker grillcloth when transporting it, and am idly contemplating a logo of some sort. How does this final version sound? Well, I've gigged them a couple of times as a (bare wood) pair and a (nearly) finished single cab and I really like it - clear, articulate and smooth. It doesn't boom and tweet and as a result, with the Markbass F1 on flat almost sounds bass-light because of the clear midrange, but this is deceptive. It gets pretty loud and deep when you want it! I'd love to try them with an SWR-type creamy valve preamp as I think they'd be awesome (I do wonder if the MB fusion could deliver this in a micro package). They were designed to give me a killer jazz bass sound in a tiny package and I really think they deliver. As a bonus if I wanted a more hyped up bass sound without EQing it in, then I could swap out the Celestions for the Eminence 2510ii as they'll also work well in this cab and give an instant scooped boombox 10" driver sound.

As you can see in the previous picture, the grill is held on by rubber feet. There's a reason for this rather odd arrangement apart from the fact that IMO it looks a bit cool and quirky in an oddly Scandinavian 1970s way. First I wanted maximum flexibility for stacking with these cabs, but also to use a really good comfy handle - which for me ruled out the recessed ones meaning whichever side it was on would not be stackable (the cabs were built with offset baffles in mirror image to minimise driver spacings whether stacking on long or short edges). Second, with the prototype I found that the easiest way of carrying a cab one-handed is with the longest edge horizontal against your body, and the shortest edge horizontal perpendicular to this. So both things pointed to putting the handle on the back. In this pic you can see this and also that I dealt with the vinyl seams by cutting a thin channel into the wood, overlapping the vinyl slightly at this point and holding it in with beading to give a smart finish: [attachment=108881:DSCF1569.JPG] This, with the nice leather handle, small overall size and light weight makes it exceptionally comfy to carry! Luckily given the expense, the poplar made a noticeable difference when comparing the final versions with the prototype.

So next was addition of the vinyl itself. Rather than a loudspeaker tolex I went for a premium high-abrasion-resistance contract vinyl, designed for heavy-duty commercial upholstery. Decent grade PVC on a tight weave polycotton scrim. Drawback is it's more difficult to work with as it's thick and the backing is not the same colour so seams are difficult. I also decided that this look would suit a retro grillcloth so put some speaker cloth on the grill, glued on to help keep it looking tight and neat. Here's a couple of pics of one very nearly finished cab, one thing I will change is to replace the panhead screws holding the corners with countersunk screws inside round-edged finishing washers so they're not liable to scratch anything they bash against. [attachment=108880:DSCF1570.JPG][attachment=108879:DSCF1569 (2).JPG]

So for a finish I decided the poplar ply really was too soft for any of the brush/spray versions, even rubber/polyurea-based, to be viable. I really wanted these cabs to be smart and 'professional' looking enough for functions gigs, and I feel people often judge these things on quite superficial aesthetics rather than performance (fair enough on here where you can't hear them anyway!) so felt the looks should match the material and driver quality employed. Tolex (vinyl fabric) is hard to beat on looks but people often complain it gets tatty quickly. I decided that some padding would both help protect the poplar or at least hide dents, and also protect a top layer of vinyl as the cushioning would help prevent it tearing due to catching on stuff. I would've liked to use closed cell polyolefin but gluing is a bit of an issue, especially to tolex, so for the time being I've used an open cell (polyurethane?) furniture trim. You can see the folded-edge grill here too. Definitely worth the extra effort.

Right, so this has been a very boring build diary since other things got in the way, but finally I have nearly finished these cabs in case there is anyone out there who still cares! Afraid I didn't take pics all the way through. But. Rebuilt the cab as a pair based on the prototype but tweaked the port length to drop the tuning slightly, bringing it pretty much to 55Hz as intended. I also abandoned the rear-mounted driver idea for these versions for finishing reasons, so lost a tiny amount of internal volume with the required extra 12mm recess but the acoustic difference this makes was fairly negligible in the real-world with a port length adjustment to maintain the tuning frequency. This time rather than a flat grill, the edges were folded over which adds a really worthwhile and noticeable extra rigidity. To prevent ringing I mounted it onto padded vinyl-covered wood in the corners and put a few extra blocks below the baffle to further deaden it and add more strength. It would be very hard to damage the driver by kicking now! [attachment=108875:DSCF1494.JPG]

[quote name='Truckstop' timestamp='1338021304' post='1668649'] The area of the port has been cut by about half. Had I though ahead I probably would have gone out and bought some thinner batons to make the grille with, but I am a very impatient person so I just cracked on with whatever I had to hand! [/quote] Hi, looks great, nice work! I notice you say you had problems with the adhesive, was that the Stikatak brush stuff that I recommended? It does have quite a slow tack time which can be good or bad... Unfortunately I do think that your port grill will cause problems, as well as lowering the tuning with the batons, it will impede the air flow causing issues with turbulence at higher volumes - cab ports are usually left uncovered (or with a high-void-percentage grill offset a cm or two) for a reason. I'd suggest you try with and without at a decent level to see if it matters to you.

I particularly like the way it's the best condition 1st year jazz bass on earth... and to photograph it, they take it out into the sun and lean it precariously against some Chinese ceramics standing on a rough brick floor

Gotta be slightly careful buying glues for vinyl fabric (flexible PVC). Plasticisers in the vinyl can leach out and stop the glue setting properly. Using a proper flexible vinyl adhesive is the safest option - I've used Stikatak from B&Q (check the vinyl flooring section) as a brush/trowel on glue and it's pretty forgiving, takes a while to dry so allows for repositioning but sticks well when dry. It's also fairly cheap, just under £4 for a litre pot or £8 for 2.5l and is water-based so low on the nasty VOCs. Stikatak also do a vinyl spray adhesive that I saw in B&Q which may be faster? Many spray adhesives will specify that they're not for flexible PVC even if they're fine on uPVC (the rigid kind). Hope that helps!

[quote name='brensabre79' timestamp='1337612419' post='1662752'] I should chip in here and say that although both use the same 12" drivers the Super12 is not simply the same as having two Midgets, the sound is different. Alex was at great pains to tell me that the way the two speakers 'couple' in the same cabinet on the Super 12 is what makes it, well... Super! It has the effect of altering the frequency response of the Eminence drivers and fills the little scoop in the low-mid, generating a flatter response than the Midget. This is probably what contributes to the Super12s reputation of being 'middy' I don't have any trouble getting really low synth bass frequencies out of mine at all, its just a really flat response so you can dial out what you don't like - instead of having to dial in what is missing [/quote] I'd guess from dims that the internal volume of the S12 is also slightly bigger than 2 midgets so you will get slightly more low extension that way too. As I said on another thread the 3012HO freq response makes it a great candidate driver for using in multiples, better than alone really.

[quote name='BottomE' timestamp='1337608481' post='1662655'] Seems to be 2 schools of thought here.[list] [*]Those that use the PA should pay for it [*]Everyone should pay for it [/list] I think after looking at all the posts... The singer is cool to get her own monitors - agreed. Why she doesn't have any in the first place is up for debate but hey ho its a decent offer. The guitarist is being a twat for expecting to own something (and use in an unrelated project) that we are all expected to pay for. He can Foxtrot Oscar on that. If we get a more powerful rig that all can use i'd be happy to pay my share. If they opt for a shinier newer version of what we already have then they can pay for it. I thank you [/quote] This sounds totally fair and reasonable to me!

[quote name='ThomBassmonkey' timestamp='1337606722' post='1662613'] If your band has distorted vocals because you're using a cheap PA, that's a huge problem and will cost you gigs. If your bass sounds a little muddy because you're using a cheap amp, it's not ideal but it's far better than screwing the PA up. It's always joked about on here but there's an element of truth when people say that punters don't listen to the bass. There aren't a lot of people out there that will say "the bassist is only using an Ashdown Evo 300w? Nah, let's get someone else" compared to "whenever I see them the vocals are quiet and sound horrible, let's get someone else". [/quote] I'd agree that vox sound quality is probably the most important thing. But, the scenario I was referring to was comparing vocals only through PA versus the whole band. That's not the same as bad or good PA. A genuinely good quality PA for vocals alone is affordable for about £1000-£1500 now (coincidentally similar to what BottomE's rig cost). If you want to put a lot else through it and maintain the sound quality, that price probably trebles because of the extra engineering complexity required.

[quote name='Mr. Foxen' timestamp='1337601660' post='1662488'] Plus using an amp eqed for a different cab is like saying a line of shoes are no good because you tried someone else's pair that were a different size to you. [/quote] I'd agree - but it's worth noting that cabs with particularly uneven freq responses require complex EQ capabilities to alter usefully, which has several disadvantages. Overall I'd say the best cabs are either those with a fairly gently sloping profile that matches what you want, or else just pretty flat allowing you to tweak to taste with just a couple of well-chosen EQ points - where matching heads to cabs comes in. I myself like fairly flat cabs or with a slight upper-mid bias (not as extreme as the 3012HO).

Doing sound I have gone from mixed set-ups, through putting everything through the PA/monitors with absolutely minimal backline, through to a much more old-school set up with PA devoted largely to vocals/keys, and perhaps reinforcing drums where necessary. Which is best depends totally on the application and the musicians involved, so I respectfully disagree with Monckyman that it'd necessarily sound 'mediocre'. It can, but if people have decent amps/cabs and know how to control their volume/dispersion there are a lot of clarity benefits to restricting what goes into the PA, especially with cheaper/mid-priced speakers (eg typical Mackies, JBLs). I think the people who're arguing that a PA makes the band sound better even if just for vox are ignoring the point that a good bass amp/cab also makes the band sound better, and also costs a lot of money. If you want to put that money into a small/cheap combo for stage monitoring and the rest to PA, that's a different solution - maybe a better one but that depends on how much you as an individual prioritise that band over anything else musical you may be doing.

[quote name='chris_b' timestamp='1337353611' post='1658718'] In terms of volume I could probably get away with a 110 but tone is the deciding factor. Several years ago I did suggest that Alex made a high quality 2x8 for small acoustic type gigs. I'd be very interested in one of those. [/quote] There is a long-throw neo PA driver made by Faital that is getting a lot of interest in the DIY community, the 8PR200, and the person behind the fEarful cabs in the US has commercialised 1x8 and 2x8 designs using this called the Crazy8. Apparently this has a very nicely integrated tweeter such that it does a good job on PA/monitor as well - sounds like it might suit your application well? There is a fibreglass(? I think) composite version available which should make it incredibly light too. I thought about using this driver for DIY but decided a pair of 10s would suit me better for the slightly bigger gigs, was a tough choice though and I still might make an ultra-compact 20 litre 1x8 when funds and time allow. B&C also have an 8" neo driver that should be a good one, and Celestion have previewed one for bass guitar that wouldn't be quite so powerful/clean but would be the lightest weight of the lot. I assume they're making these because someone wants them, so I wonder if the market's about to be flooded with high spec 8"-based designs?! Btw if you don't like the Midget I wouldn't tar all Alex's designs with the same tonal brush... that particular speaker in that small a box is going to be very toppy and bass-light unless you EQ heavily (which it's able to take if you've got the power) but something like the Big Baby would be a lot smoother and deeper, even the Compact will sound more even.

[quote name='Mr. Foxen' timestamp='1337558531' post='1662078'] Which SVT driver are you thinking of? They've used loads, but the original CTS and the Eminence B810 that is supposed to cop its tone are the ones that made the mark, with plenty of quitary top. There nasty low mids and nothing else period I have noted somewhere where they used high power handling drivers with no top. I was going to do 2x10s that were a single section of the 8x10, but then I realised I'd just invented the guitar cab. [/quote] Hmm, I'm not sure which drivers I'd have heard but the graph for a single Legend B810 matches well with what my ears hear when there's 8 of them http://www.eminence.com/pdf/Legend_B810.pdf It's already strong in the low mids (maximal ~150-300Hz) and shy in the upper mids, stick 8 together in a sealed box and you're really going to accentuate that as they sum coherently until around 500 or so then start combing above, which will roughly translate to a freq response heavily skewed to the low mids. Can't find a definitive graph but there's one from a Line 6 model on Greenboy's website showing a freq response that rolls downhill all the way from a few hundred Hz, you may have to be logged in to see the thread but it's there on google image search if you're interested. Incidentally, for a more modern application, the Kappalite 3012HO is actually a great driver for using in multiples as it has a gently rising response all the way from ~300Hz - think this is what's in the BF Super 12? A couple of them stacked up would work very well. Or there's the 18Sound 10NMB420, which is pretty much perfect for this application and 16ohm to boot. That's definitely be my driver of choice for a pair of loud stacked 210s. http://www.eighteensound.com/index.aspx?mainMenu=view_product_simple&pid=274

[quote name='Mr. Foxen' timestamp='1337547543' post='1661887'] Have to rejig things because with half the speakers doing midrange, they need to be doing it twice as loud as before they were split on axis, but its more consistent as you head off axis, needs a whole redesign to get a flat cab, or eqing to suit. [/quote] This raises a related issue which people often seem to overlook in more conventional cabs, the 'ideal' driver for say a 1x10 or 2x10 would have a very different freq profile to that for an 8x10, for a given goal. I personally really don't like the low mid hump that an Ampeg fridge develops because of this and would favour a high sensitivity upper mid-biased driver in that application, that on its own would sound thin. [quote name='bertbass' timestamp='1337554435' post='1662027'] Actually it's quite easy to check the science for yourself, just go for a wander round the venue with a transmitter or extra long lead during a sound check and hear the difference in sound/ tone from stage to audience. [/quote] Or just listen to any guitarist through a 4x12 from the side and then from the front and get slayed by the beam of death! It's so easy to hear on guitar... but if you do sound for other bands you find it quickly becomes an issue for bass guitar as well. I'm actually a bit suprised this thread is still going, thought it had totally been done to death! It's nice to see a bit more application-specific logic being applied though, rather than just saying 'vertical stack, always!'. I've played [EDIT - and engineered] plenty of gigs where vertical dispersion is more of an issue than horizontal

It's more complicated than absolute volume - take a hypothetical bi-amped rig with SINGLE large driver for the low end that's capable of moving the same amount of air as an 8x10 (ie total amount of energy that converts to sound is the same), EQ it to the same notional 1w/1m response as the 8x10 and then put it side by side with the same 8x10. Stand 3 metres away like on a biggish stage. It will sound different. The 8x10s will have a much narrower vertical dispersion - at 'medium' distances from the cab it will sound way louder at certain frequencies because the same energy is projecting into a narrower band. Your head will also be a bit closer to the source than the single low speaker if it's on the floor (with mids from a separate driver above). The other thing is that without the EQ, the 8x10 will likely be way more tilted towards the lower mids than a typical single larger driver. Speaker outputs are only additive up to frequencies dictated by driver spacings, above which it starts doing all sorts of crazy combing. Anyway, none of this stuff is capable of producing really big true bass, only BIG PA subs will do that! I suspect even 10 metres away the PA subs the OP talked about would contribute significantly. But actually for most gigs I personally prefer the tonal profile of a smaller rig

[quote name='Twigman' timestamp='1337014158' post='1654026'] Think I might get a quote from these guys.....to strip the chrome then nickel plate [url="http://www.ashfordchroming.com/dechroming"]http://www.ashfordch....com/dechroming[/url] will report back... [/quote] Good luck! I still think there's a good chance your parts will be nickel-chrome plated so might be worth asking their opinion on this too, potentially save you the cost of replating

[quote name='Twigman' timestamp='1337012683' post='1653983'] So I shouldn't be believing this?: [url="http://www.ehow.co.uk/how_7614546_remove-chrome-nickel-plating.html"]http://www.ehow.co.u...el-plating.html[/url] [/quote] It will probably work if it's chrome-effect paint like you'd get on plastic. But not on proper electroplating

So I probably haven't been very helpful, sorry! But having thought about it I am also sceptical that an organic solvent like acetone would dissolve chrome (or nickel) plating. In fact I'm pretty sure I've used acetone to clean hardware before without dissolving anything other than the grease I wanted to get rid of.

Hmm the babicz bridge is aluminium apparently... not a good idea to mix with the acid (bang!), though IF it is nickel plated underneath it MIGHT still be ok. If I was going to try this, I'd use a small amount of diluted acid solution on an inconspicuous part of the bridge first and rinse very thoroughly when done. There may be other chemical strippers for aluminium that'll leave behind any nickel layer. Replating aluminium is probably more complicated than brass though so I wouldn't do it unless you know it's nickel underneath already. Maybe easier just to trade with someone who has a nickel version?

[quote name='Twigman' timestamp='1337010889' post='1653942'] Is there nickel under the chrome? [/quote] Typically yes. Whether there is for your particular hardware though, is worth checking!

Markbass amps are internally switchable, and probably quite a few others as well. The cynic in me thinks this is probably about limiting the number of people buying kit from countries where it's cheaper.

It's not something I've done, but shouldn't muriatic acid strip the chrome and leave the nickel plate that's already on there?

[quote name='Lozz196' timestamp='1336903482' post='1652444'] Why not use the volume control on the FOH for your amp, for the FOH mix, leave the volume on your amp at the levels you need for on-stage monitoring, and additionally leave the vocal monitors for vocals only? [/quote] Typically it's the directional higher frequencies which you need for monitoring, but then are too loud for the overall mix. Setting up your rig so these are firing straight at your ears but not necessarily out towards the front can save a lot of mix problems.