alexclaber

Although I referred to the 27.5Hz fundamental of the low A that wasn't my concern, and from what I've seen all the Markbass heads are many dB down by that point. The issue is likely to be the 55Hz second harmonic and you'll struggle to throw away that region without thinning out your tone too much.

Hi Mike, You mean the A below low B (i.e. 27.5Hz? My guess is that the enclosure alignment plus the speaker excursion is causing your woofer to move too far, which is thus killing the rest of your tone. I don't believe in trying cabs out shop-style - it's an artificial environment that frequently leads people down the garden path with their choices. You need to use them in a LOUD rehearsal or gig to find out if they suit. Best regards, Alex

[quote name='dincz' post='1087906' date='Jan 13 2011, 01:06 PM']"Clipping only increases the power output at higher frequencies" But the RMS voltage of a sine wave is about 0.7 of its peak value, whereas the RMS voltage of a square wave is the same as its peak value. So a square wave of a given peak voltage has an RMS value 1.4 times that of a sine wave of the same peak value. Surely that results in a doubling of power (I^2 x R)? At least in an ideal world with an ideal power supply. OK, I'm talking pretty severe clipping here - bags of level into a sensitive input - and an amp running into a purely resistive load. I've only ever tested this into a dummy load as I've always had intolerant neighbours [/quote] But if you run a Fourier Transform on that square wave you'll see that the additional energy is entirely made up of higher frequency overtones.

Hi Mike, How's the tone of the JB Combo at lower SPL? How does it change when things get loud? The answer's either going to be Compact or Midget, but it depends on where the current deficiency is - the challenge with the classic "I want clear lows" statement is trying to work out what's missing, because lows on their own aren't really clear. So is the lack of clarity in the lows due to a midrange issue, a treble issue or is it the lows themselves? Or is it indeed a problem with generating the lows causing a problem with the mids? How either cab works with the JB is a bit of a suck it and see thing - aren't you quite close to Brighton? If so, buy one, try it, if that doesn't work try the other, if that doesn't work then have your money back! Best regards, Alex

Mr Cocco, got your email, will reply to that and copy and paste the results here in case anyone is curious!

Maybe I'll write something on crest factor with respect to bass guitar. There's quite a lot to cover. But on the Claber scale of quick and dirty crest factor then: Violently slapping a sparse bassline on my RIM with Q-Tuners (passive pickups with zero compression) through Avalon U5 (extremely high headroom preamp) = highest crest factor that's possible from a bass guitar (maybe 1000:1 or 30dB or more) Live bass playing, no compression = typical bass guitar crest factor (between 10:1 and 20:1, 10-20dB) Straight 8ths with the same bassist playing the same thing as below, but live instead of studio = lowest normal live crest factor (somewhere between 4:1 and 10:1, 6-10dB) Heavily produced recorded straight 8ths with lots of compression = lowest normal crest factor (somewhere between 2:1 and 4:1, 3-6dB) Playing constant notes, no rests or muting, through a Big Muff with all the controls cranked = lowest crest factor that's possible from bass guitar (probably almost 1:1 or 0dB) The snare roll example is a good one - just bear in mind that the extra rimshots not only raise the peak level but also the average level - so the less frequent but louder the rimshots, the greater the crest factor. Turning up your treble will increase the crest factor whilst turning up the bass will decrease the crest factor. Adding compression or limiting will decrease the crest factor. Adding distortion will decrease the crest factor. Plucking closer to the bridge will decrease the crest factor. Plucking harder will increase the crest factor.

[quote name='Merton' post='1085983' date='Jan 11 2011, 08:01 PM']What's your current condition? Doesn't sound good![/quote] Broken ankle: Was operated on last Friday (I have new titanium upgrades) so on a mission to get it back to normal asap!

I'm taking advantage of my current condition to get on top of not only the thrilling paperwork I generally avoid but also some R&D I've been meaning to do, and writing some more articles to address this, that and t'other that I see getting discussed on forums but rarely getting resolved. The first one is here: [url="http://barefacedbass.com/technical-information/mythbusters1.htm"] Mythbusters #1 - Amplifiers[/url]

I'm not sure anyone has. Lots of Bass Terrors working well with Midgets and Compacts though, and all three cabs are pretty similar so I'd expect good results, subject to you liking the tone of the Bass Terror!

Here's the full article as it left the editor's desk!

[quote name='Sean' post='1077806' date='Jan 4 2011, 08:19 PM']Issue 62, page 70! Alex's column. There's a graph missing with a badly cropped random photo in its place and the graphs that are there don't have their axes labelled. Hopeless. Great column this month though and I'm definitely trying the guitar combo hint this Friday and I know it'll cost me that pint![/quote] Just got this through the door - aaarghhhh!!! The badly cropped random photo appears to be a cropped enlargement of fig. 4 and thus the real fig. 1 which the article keeps referring to has been omitted. Brilliant. The first plot does say dB on the y-axis but I'd assumed the axes were obvious, so that's my mistake. Here are the correct illustrations before I hop off on the warpath...

[quote name='Merton' post='1071272' date='Dec 28 2010, 09:09 PM']Have Eminence got a 3015 / 3015LF equivalent in 10" diameter? I wonder if that's the sort of direct Mr Claber is heading?...[/quote] No, totally different direction! These 10"s don't even have neo magnets, but purely because we're going for a more valve amp friendly motor, which means you can make a ferrite magnet and the resulting frame quite small and light so neo would have only marginal weight benefit and the reduced power compression from typical neo motors isn't relevant with the low power output from valve amps.

Mr Protium, you're putting 2 and 2 together and making 5! Statement One: Every speaker driver ever made is imperfect and thus has colouration, which is a product of the numerous distortions inherent to every driver. Statement Two: These distortions, and the resultant colouration, are not directly related to the nominal diameter of the speaker. Therefore we can say that every speaker has a sound. And we can also say that that sound is not related to the nominal diameter of the speaker. The original Ampeg 8x10" contained eight 10" drivers which were essentially guitar drivers. We will get that sound by using a suitable guitar driver, to cover the part of the spectrum where that colouration is critical - note that early Ampeg 8x10"s sound brighter and more open than later ones, and this design aims to match this. The other drivers are mid-bass drivers with greater Vd, so the cab can handle more power and produce bigger clean lows than the early Ampeg 8x10"s. Finally there is a completely unique crossover to split the signal so that the guitar driver is not hit by too much bottom, and so that half the speakers only produce lower frequencies to ensure excellent polar response. And also the speakers, crossover and enclosure have been designed to have a very smooth impedance curve for better coupling with output transformers, which should result in better power output from valve amps (closer to ideal conditions) and longer valve life. The only similarities to our other cabs is we're sticking with the same thin-wall heavily-braced and pre-stressed construction and the exterior look, and that we're continuing to obsess over polar response. But it's very much a cab with a sound, and hopefully "The Sound" for those who like that sort of thing.

10"s don't have 'a sound'. Every speaker ever produced does have 'a sound' because none of them are perfect, but there is no correlation between that sound and the nominal diameter. This will be the first Barefaced model that targets a particular colouration rather than aiming for minimal colouration. It will be a conventional looking 6x10" however it will exhibit the same off-axis response as a single column of 10" speakers because half the speakers in the cab will only produce lower frequencies.

Not just my opinion, it's fact (with the caveat that sub-par cabs don't count!) Figuring in everything (sensitivity, response, psychoacoustics, etc) I think the '69er is likely to sound about twice as loud as your 2x10" when driven by the same amp. Cloth grill will be a cost option, as steel grill cabs are significantly quicker/easier to build.

Indeed they are. We have a selection of large cabs coming out next year though: Dubster - ska/reggae/dub specific 2x15" Super Fifteen - full-range 2x15" (two Compacts in one box) Big Twin - louder and deeper version of the Big One (2x12"+6.5", optional tweeter) '69er - valve amp specific sealed 6x10" designed to get the original 1969 8x10" sound with greater power handling and improved polar response

Yes, it weighs 33lbs or 15kg, so slightly less than expected!

Great fun! My apologies for spending most of the day hiding in the jam room, much of it playing the drums badly - I'm clearly suffering a lack of jamming since my band went on hiatus. Next time I shall endeavour to be more keen to talk about basses, speakers and all that, instead of just wanting to hit loud things!

One tip for everyone taking photos - avoid using a flash if you can because the gloss finish reflects it harshly. Natural light photos look much better (and more representative of reality!)

Hi Ferg, As Mr Snickers said the key is to look at the tone and loudness you need plus the bass, amp and your playing approach and that then determines the cab or not. I gather the SVT3 makes a lovely fat mellow sound with the Compact but isn't loud/aggressive enough for noisier environments, in which case I'd recommend a Midget/Compact stack or a Super Twelve. Let me know more precisely what your gig situation is (style, repertoire, venue sizes, what your drummer/guitarists are like) and then what your 'ideal' bass tone would be (YouTube clips or Amazon samples please!) plus what bass you play, and then I can point you in the right direction. Best regards, Alex

The 3012LF needs a bigger enclosure with much larger port area to get the best from it whilst the 605Nd should be in a small sealed cab. You'd also need to build a suitable crossover, which is complicated, and the end result will be noticeably lower in voltage sensitivity without getting the upsides of the 3012LF due to the cab it would be in.

I'm more than happy to fake it on the drums. Whether anyone will want to hear the results however is a different matter!

Someone said something about using their Trace Elliot with graphic EQ for my EQ/tone whatnot and I don't think I replied. Yes, the more EQ the merrier! It would be useful to compare how to use a graphic vs a semi-parametric. The irony is that I hardly use EQ at gigs - but when mixing recorded stuff I'm quite keen on careful subtle sculpting!

Is it that amp power is misleading or is it that most bassists don't realise that you only get full power just before your amp clips? And if you're playing in a loud band, using a smaller cab and don't have thousands of watts you will frequently hit full power on the attack of louder notes.

I think that pretty much sums it up! There are lots of nice 1x12"s out there but very few that can handle LOUD gigs on their own. Add a second and you get 6dB more max SPL which is a lot. Alternatively use much more expensive drivers and you can end up with a 1x12" that is closer to two normal 1x12"s in max SPL, than it is to one common or garden 112. This does make it a lot harder to make it light because you're using a much heavier driver, which increases the cost further, but such is life... [url="http://barefacedbass.com/uploads/Barefaced%20Specs%20Oct%202010.jpg"]Barefaced Specs[/url] Note that the LF sensitivity is almost entirely proportional to the size of the cab - but deepen the response (i.e. lower the F3, F6 and F10) and you lose LF sensitivity unless you increase the enclosure size. So regardless of your budget, any cab that isn't boomy (you can cheat a bass cab louder in the true lows by making it under-damped but that's not good for tone) will be tied to the same LF sensitivity and roll-off points for a given size. So from that you can probably guess that the Aguilar sensitivity spec isn't a LF sensitivity one!