Gottastopbuyinggear

Thanks all. Went for the 3mm option in the end. Did a test first in what I think was a bit of Beech, and it seemed plenty strong enough. I bought a brad point bit which helped with accurate drilling no end.

I looked at three Jazzes in a shop today, two MIM classics and a MIA. The positions were (basses hanging on the wall) one lot at 10 o'clock, one lot at 2 o'clock and one lot at six...

I have a new neck to drill for a parts build. I've read before that 1/8" is the correct size bit for the neck screws that come with the Fender neck plates, which is roughly 3mm. I think I've also seen 3/32" stated, which is just under 2.5mm. I've measured the screws with vernier callipers - 3mm diameter shank and 4.2mm diameter including the thread. If this was just a bit of softwood then I'd probably use a 2.5mm drill - which I happen to have. I understand that Maple is quite a lot harder, though. Should I wait until I can get hold of a 3mm bit? I'm not a seasoned woodworker as you might have guessed...

Are there a pair of resistors attached to the pots, with the tip of the jack socket connected to the middle of those resistors? If not then I can see how a dodgy (earthed) pot might kill the sound. It could be that you've got a very fine strand of wire in there somewhere which is shorting out. And apologies for stating the obvious, but be careful with those headphones on and everything turned up full, just in case it starts working again as quickly as it stopped!

Have you got a multimeter or continuity tester of some sort? If so then I'd suggest using that to check if the hot output has somehow become grounded. The only other thing I can suggest is getting some crocodile clip leads to bypass the jack socket and connect directly to the jack plug on your lead, and working through the hot wires to see if you can find a point where you get some signal, though that's possibly not going to work if you have got it grounded somewhere. It's a tricky one!

Is there any sound if you plug in and play with the bell plate off the body? Reason I ask is I've seen a jack tip connection grounding on shielding or conductive paint before.

[quote name='Phil Starr' timestamp='1491296123' post='3271825'] !4 kg is good, my originals came out at around that without the horn and crossover, though my bracing internally was a bit agricultural (rushed for the last bass bash) and I used Baltic birch rather than poplar. [/quote] My Mk 1s in 18mm Poplar, with all panel to panel joins reinforced with 20mm square battens, are also about 14Kg, hence why I thought the Mk 2 in 15mm would possibly be lighter. I think I recall seeing an estimate earlier in this thread of up to 16Kg, but I may have made that up. [quote name='Phil Starr' timestamp='1491296123' post='3271825'] Yes I'm looking at doing a 40litre version, possibly even smaller as I might do some prototyping with a bit of spare ply. Basically I find I always end up dialling in a hump at 100Hz and rolling off below 40 anyway, the response you'd get in an over small cab. That's fine with my Harke amp with a graphic but is proving harder with my Mark Bass amp. I'm wondering why I'm carrying extra wood to not quite get the sound I want. [/quote] Not the sound you want - now he tells us! I'm still relatively inexperienced with all this (from a user point of view) so I'm quite keen to do a bit of experimentation to see how a different speaker would sound in the real world. I need to revisit the modelling to check but I did look at putting a Beta 12 in the Mk1 cab (partly to free up a Beyma for a Mk 2 build, and partly just for curiosity) which I think predicted a similar bump of 2 or 3dB around 110 Hz or so. Of course the Beta 12 does have a pretty big hump in the high mids, so overall I guess the sound would be substantially different.

Well done for getting it finished and to the bash - that's real dedication for you! At some point it'd be really interesting to know how close this is to the original weight estimate. I have a hunch, based on my 18mm poplar Mk I cabs, that it might have turned out a bit lighter than you thought it would. Note that I deliberately avoided a straight "How much does it weigh?" question - that'd only invite someone to come along and ask if it's any good for metal

This place has them - maybe not very cost effective, though: http://www.cdguitars.co.uk/schaller-strap-lock-spare-nut--washer-chrome--14230200-1231-p.asp

I think C is wrong in the LF crossover circuit for the feed to the HF crossover? The input to the HF crossover should be the same as for the LF, but C puts it after the inductor?

I'm relatively experienced building effects on stripboard, have done a bit of PCB etching in the distant past, and have successfully built a couple of the Mk I cabs, but I have to admit I didn't have a clue what material to build a crossover on. I can see from that link that those have been built on ply - is that the easiest or recommended way, or is there a more appropriate alternative?

The one that winds me up is the regular invitations to follow Mark Zuckerberg. No thanks! I don't get any other "follow this person" type alerts, and I've indicated I'm not interested, so why keep bothering me?

[quote name='stevie' timestamp='1488877310' post='3252491'] I wasn't going to post anything controversial on this thread, as I didn't want to distract too much from the DIY content. But you did ask! [/quote] Nothing controversial there at all, I think. I'm pretty sure that a single Mk II will be more than enough for my needs, and I fully understand the reasons why the commercial box shifters design and build to particular price points, etc. I don't want to distract any more, either - I'm eager to see the design details for the Celestion driver version, and how you get on with the Poplar ply build, so I'd better let you get on with it! But thanks again to you guys for taking the time to post these threads - they're entertaining in themselves, and it's hugely satisfying when you take the knowledge and actually build something from them. As for the theory, there comes a point when you have to accept that there's

Well as it happens, Stevie, I do play a P bass with flats! Before I set off on my Mk1 builds last year I started a thread about considering a 2x10 build. It wasn't long before I was convinced that the best thing to do would be to go with the original Basschat 1x12 design, which was just emerging at that time. I have a suspicion that I'll soon end up abandoning my recent thoughts of a lightweight neo based build and just go with the Mk2 design this time around. I was going to stop asking questions, though another one popped into my head almost as soon as I posted, to which I think I already have the answer. Presumably combining a Mk2 and a Mk1 cab isn't going to present any problems with a 4th order crossover as there's effectively no phase difference, but there would be phase issues with a 1st, 2nd or 3rd order crossover? I wonder whether commercial manufacturers who offer both tweeter and non-tweeter versions of cabs address this, as you do hear of people pairing a non-tweeter and tweetered cab quite frequently.

Aha. I was never very good at analogue electronics when I did my degree the best part of 30 years ago, I've forgotten almost all of what I did understand in the intervening period, and I'm probably not going to dust off my copy of Horrowitz and Hill now... However, a short answer to satisfy my curiosity on this would be really good - I can see something that looks like a 2nd order crossover there, but there's obviously some other stuff going on. A quick Google suggests that's impedance stabilisation on the tweeter? Presumably it's things like that which many manufacturers are skipping? What's with the other resistors - just attenuation?

[quote name='stevie' timestamp='1488720793' post='3251242'] I don't mind designing the crossover as long as somebody lends me the drivers. [/quote] If we were talking about both drivers being 8 ohm then would the crossover need to be any different from the one you've already designed? I could understand it being different for a 4 ohm woofer.

Having read Stevie's comments I took a look at the Faital Pro PR300 specs and tried some models with it in WinISD. I'm pretty green at this stuff so I could well be interpreting things incorrectly, but it looks to me like you can get a similar response to the Beyma in the Mk 1 cabinet from the Faital in a smaller cabinet (about 46L) tuned about 5 Hz higher. If so then this would mean the weight of the cab would be reduced a bit, and the weight of the horn offset by the lighter weight of the neo woofer. The reason I've been looking at this is the possibility of a pretty lightweight single cab solution, and the Faital driver comes in 4 ohm as well as 8. From looking at things in WinISD I estimate I'm probably getting a maximum of about 5dB more from running two of the mark 1 cabs compared to just a single, and at similar overall power I'd get about 2.5 to 3dB more out of a single 4ohm Faital loaded cab compared to a single Mk1 cab. In the real world, that may or may not be noticeable, of course. Apologies if this is going off at a slight tangent - I don't want to derail the thread but I find these threads are great for learning and firing the enthusiasm for trying stuff out. I've just been through 6V6's 1x12 build diary, and the What 12" driver thread that preceded it, and there's a huge amount of information there. Ive also revisited Beer of the bass's 1x12 build diary, so coupled with this thread I now want a Basschat Mk2, a lightweight 4 ohm cab with a similar frequency response, and a Beta 12a loaded cab to see if I like the character of that driver, as many seem to.

I wouldn't rule out the Ampeg PF500. The issues were sorted out a few years ago, so as long as you pick up a relatively recent one then you should be okay. Mine is a couple of years old and has worked flawlessly. They go for relatively low amounts second hand too, so you could probably justify keeping the MB200 as well. Another possibility would be a GK 700RB - there was one for sale on here recently.

Here's the source for the grille cloth: http://www.ebay.co.uk/itm/Fender-Black-White-Silver-Grill-Cloth-94x93cm-/162388675451?_trksid=p2141725.m3641.l6368 In fact they're actually wearing perforated steel grilles now, courtesy of speakergrills.co.uk. That was a decision based on the added protection, since they're going in the back of the car with amp, pedalboard, mic stands, floor wedge, plus guitarists gear etc. I'll have to get a couple of pics. Still very pleased with them. Easily more than enough oomph when used as a pair in my 2 x guitar, keys and drums pub band. Flat response to my ears, plenty of bass. Possibly not for those who like a bit of high end sizzle, but see the guys' new design thread over in amps & cabs if that's a concern! My Markbass 2x10 was redundant after this build and has just been sold, and I've only been trotting out my Ampeg PF115 when the weather's bad as I didn't have any covers for these. At least, I didn't until: http://www.ebay.co.uk/itm/141784444756?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT Chop the handles off those and they fit a treat!

Pocket joints and dowels combined could be quite good - a few dowels for alignment, and pocket joints to draw the pieces together. I have to say that I'm not hugely keen on the woodworking aspects myself. I had the ply cut to size for the cabs I made last year, and would do exactly the same again to save faffing around with squaring edges with a router (I don't have a circular saw). Two more questions if I may. First, if someone wanted to maintain the same dimensions as the original build then could the port be put on the rear panel, and would there be any disadvantage in that? Second, does the added tweeter open up any alternative 12" drivers, since the need for a wide frequency range is reduced? I was looking at the Kappalite 3012LF recently, for example, though I don't know whether that would actually be any better - I've not got around to trying to model that in WinISD yet, and to be perfectly honest I don't think I know enough to be able to do that with any degree of confidence anyway!

As the proud builder and owner of two of the original Basschat 1x12's (and as someone who's just sold a 2x10 cab due to lack of storage space) I shouldn't really be interested in this. But... I am, so I'll chime in with a few comments and questions. I used 18mm Poplar ply in my build, but with the exception of battening every joint (and I do mean all 8 of them!) for safety and ease of build I haven't added any further bracing. I don't think the cabs have ever been driven particularly hard, but I've never heard any issues that I'd put down to panel vibration/resonance. To be clear, I haven't noticed any issues at all, and they do sound excellent to me! Out of interest regarding commercial cabs, I did have a quick poke around with a camera in the Purple Chilli 1x12 I had for a while and couldn't see any bracing in that, although it's possible there was some hidden by the wadding. The Ampeg PF 115 HE I have has only a single batten bracing the rear panel... Given the lack of bracing in my existing cabs (which might be a problem if driven harder as a single), and the appeal of having something you can perhaps hear a bit better when you're standing almost on top of it, I'm quite interested in building this new version for rehearsals and perhaps those gigs where, for ease of access, length of set, etc. I don't want to monkey around with two cabs. Do you have any idea of the target weight for the final design? I think my 1x12's worked out at about 14 and a bit Kg each, which is pretty good. Ideally I'd have something slightly less deep to make carrying even easier, and given the increase in height (or width, depending on how you look at it) for this cab you'll have decreased one or both of the other dimensions - can you confirm which one? As an alternative to battening every joint, and not owning a set of clamps, I've wondered about using dowels for aligning the panels. I've also thought of cutting the braces from single pieces of plywood - possibly a bit wasteful, but neat, and I wondered if that might increase the strength a little. Any comments on either of those approaches?

I quite often nip into PMT Cardiff on a Saturday morning for a quick mooch around while Mrs Gottastop is in the shops. I find it quite embarrassing, actually - they always ask if I'm okay, do I want to try anything, etc., and I'm invariably in there just to kill time and see what's new. Have tried stuff out a few times, and to be fair we did buy my son's bass there. Similarly good experience in PMT Bristol - they let my lad try out a bass that we said we had no intention of buying, and I spent hours in there with suitably attentive help (just enough, not over the top) when I bought my Les Paul a couple of years ago.