LawrenceH

[quote name='Bill Fitzmaurice' post='1055608' date='Dec 12 2010, 01:30 AM']The vertical spacing doesn't enter into it, as the distance between the LF and mid elements of adjacent cabs in stacked arrays is less than the CTC distance between those within each cab. For example, the JBL Vertec VT4888. The woofer CTC is about 24 inches, which is 1wl at 565 Hz. The CTC distance from woofer to woofer in adjacent cabs is about 15 inches, 1wl at 900Hz. The actual crossover used is 350Hz, well below the maximum allowable of 565Hz. That's all about system efficiency, as the direct radiating woofer sensitivity is only 98dB, whereas the horn loaded mid sensitivity is 102dB.[/quote] Ahh I think we're talking at cross purposes slightly, never mind I didn't get from your description the cab layout you were talking about. Still, slightly different to the situation where you allow low end signal to every driver but full range to the centres. The JBL crossover point still makes sense wrt CTC distances if you aim for half-wavelength rather than 1, but point re horn efficiency taken.

[quote name='funky_numba' post='1043231' date='Dec 1 2010, 01:40 AM']I normally play thru my pc soundcard however, I have a second hand TEC20B Starfire bass practice amp which I bought with the bass. It has a few pots .. 1 low, 2 mids and 1 high (i think) but they seem to make little if any difference to the sound. I wonder if the bass amp is gubbed!!! My bass still sounds 'muddy' through that amp.[/quote] Oh yeah. Does your bass have a battery in? If so then running through the soundcard is probably ok. But if not, then it will always sound 'dead' through a soundcard because of impedance mismatch unless the soundcard has an input specifically for guitar. But really, it's very hard to diagnose if this is worth sorting out over the internet. If you're ever in Edinburgh send me a PM and I can help you out.

[quote name='funky_numba' post='1055596' date='Dec 12 2010, 12:46 AM']I had the same problem. I lowered the action on the e-string and get fret buzz. I think I have passive pups on my bass. I still don't get the intonation thing.. the 12th fret harmonic???? Thanks for your help.[/quote] The frets on a bass guitar neck are spaced apart according to a mathematical formula. It's designed so that once an open string is in tune, when you fret the string those notes will also be in tune. For example, if I play an open E on a perfectly set up bass, then when I play the first fret on the same string it will play an F, second fret F# etc. However, the formula relies on there being a set 'scale length' (not the same as a musical scale). That is, the fret spacing only works if the string is a certain length from the nut to the bridge end (typically 34 inches). If it's the wrong length, then if I tune it to E open, when I play the first fret instead of being an F it will be a slightly flat or sharp F depending on if the string is too long or too short. This problem will get worse with each successive fret, so by the time I hit the twelfth fret which should be an E again one octave higher, it will sound very out of tune indeed. The way to solve this problem is to change the length of the string by adjusting the bridge saddles back and forth. We don't do this to tune the instrument routinely (although confusingly you do on a cello or similar), we just use it to set the intonation. Day to day tuning on a bass guitar is done with the pegs. One way of checking the intonation when setting it is to use the 12th fret harmonic and to compare it to the note when fretting at the 12th fret to make sure they're exactly the same. To play a harmonic, very lightly touch your finger on the string exactly over the 12th fret line, and whilst your finger is touching the string at that point only,play the string. You will hear an octave harmonic, a note that resonates one octave higher than the open string despite the fact that you haven't pressed down behind the fret. Now when you fret the note at the 12th and play it normally, you should hear the same note. If the note you hear when fretting is flat compared to the harmonic, then you need to move the bridge saddle towards the neck (shorten the string). If the fretted note is sharp compared to the harmonic, you need to move the bridge saddle away from the neck (lengthen the string). Note that for various reasons the correct exact length of each string from nut to bridge will be slightly different for each string, so you need to do this individually for all four strings. If you don't yet trust your ear enough to do this with harmonics, you can instead use an electronic tuner to check the intonation just by tuning the open E string, for example, then playing the 12th fret and seeing if it's also an E. If it's sharp, lengthen the string, if it's flat, shorten it, as before. However if you do this method you need to re-tune the open string between each adjustment. Hope that is helpful. The best way by far to understand this is to have a teacher show you! It's a LOT easier to understand by demonstration!

[quote name='Bill Fitzmaurice' post='1055348' date='Dec 11 2010, 08:05 PM']This is a commonly seen scheme with horizontal TV center channel speakers, and for that matter it's how the crossover points are determined with multiway PA line array cabs with with woofers outermost, the tweeters in the center and the mids between the two. The short CTC distance of the PJBs is no panacea. The result of using a number of drivers horizontally placed without appropriate filtering can be seen in applets such as those found here: [url="http://www.falstad.com/mathphysics.html"]http://www.falstad.com/mathphysics.html[/url][/quote] Ah I knew it must be used somewhere, cheers. Not sure I get the sense of what you mean with the arrays though, crossover points there are more determined by the constraints of the vertical spacing with respect to the lows and mids. I wondered if someone had done an applet and nearly asked if anyone had one, very useful thanks!

[quote name='Mr. Foxen' post='1055070' date='Dec 11 2010, 03:56 PM']"Tonal consistency" is very apparent in some scenarios, mostly guitarists pointing their cab at you some distance away and sitting on their cab so it shreds you with treble they can't hear. Also the old not being able to hear your folded horn cab from right in front whilst people at the back of venue are melted. I've also had mad comb filtering from running an 8x10 either side of the drummer.[/quote] Most guitar cabs are VERY directional, yeah - but that applies even to single driver cabs and is then to do with beaming and open backed cabs, I've not had serious problems with multiple drivers comb filtering per se (not saying it's not audible, clearly it is, but it's not normally the weakest link in the sound). One of the most useful bits of kit I used to take out with PA gear was a small tilt-back guitar stand, point it right at their ears and it's amazing how much (most) guitarists will turn down and roll the treble back. Then go away and immediately forget the lesson they've just learned (sigh). Separating out the bass cabs by a couple of metres or so must have sounded pretty crazy though! Pretty much everything 100Hz up would have been interfering, I'm not surprised it was audible. A lot less of an issue with the PJB stuff presumably, those small driver spacings shouldn't start combing until well into the midrange.

I've been thinking recently about the issue of vertical versus horizontal driver stacking, after my interest was piqued by the very unusual approach taken by Phil Jones Bass kit using multiple small drivers (with comparatively large voicecoils/magnets) in tandem, typically arranged in a grid. First, it made me question the assumption than in terms of controlling directionality we should always be focused on reducing vertical dispersion whilst maintaining wide horizontal dispersion. This probably only applies at half of the small pubs/clubs/etc that I've played/engineered/spectated at, where the typical set up can be long and narrow or in some cases short and shallow but with an upstairs gallery! Stage sound again, from a sound engineer's perspective limited dispersion is your friend as much as your enemy if you take it into account when setting up. Second, regarding the more complex comb filtering that one gets at greater-than-1/2-wavelength spacing, I wonder about allowing full-range signal to (or exit from) only a subset of the drivers in the stack, it's an obvious idea so it must have been implemented in some systems in the past. Even considering the typical 4x10 though, I wonder how much difference it really makes in practice to perceived (rather than measured) tonal consistency. Ears tend to be a lot more forgiving of changes to electric instrument sounds than, say, vocals. I must say I've not heard the PJB stuff, I would be interested to. (edited for typo)

[quote name='paul_5' post='1054995' date='Dec 11 2010, 02:33 PM']and of course - "tha one" [/quote] In the mids and on tha one, yeah

[quote name='crez5150' post='1054934' date='Dec 11 2010, 01:24 PM']I really don't see the benefit of scooping the EQ for slap.... you lose too much of the 'whump' from the tone. I think this is a mistake a lot of people make, they scoop the f*** out of the eq section and then wonder why it gets lost in FOH mix[/quote] Definitely. The funk is in the mids.

Larry Graham used a jazz (though later a Moon), his tone was ace. I don't think you need an active - and light guage strings may give that Mark King clanging metallic slap sound but honestly, I've yet to meet anyone who wasn't a slap fiend who actually liked his tone! Regarding 'Get on the floor'. I'd guess the closest approximation of his tone with your set-up would be the VMJ with the bridge on full, neck rolled off a fair bit. That gets my jazz 95% of the way there with that particular song, and you can always add a bass boost at the amp (I assume it's a 'ray on the original?). I do struggle to slap really cleanly on a jazz and I often wonder if a 'ray would be easier in this regard but then youtube proves it's just my technique that's letting me down! Check out 'Glide' by Pleasure, pretty sure that's a jazz.

Whilst you can get cheaper systems as separates, I think actives are pretty reasonably priced nowadays and are definitely my preference for small/medium gigs up to 150 or so people. They're great for confined spaces and versatile - for big gigs they can normally be used as stage monitors and a single cab using the built-in mic/instrument inputs is a great all-in-one solution for jams and really titchy gigs. Another thing I've found with half-decent actives is that they tend to get quite loud whilst still giving a fairly clean sound, I think the bi-amping probably helps here since you can be pushing the bottom end pretty hard but still have clean upper-mids/treble (where distortion is typically most objectionable).

Hmm, I just checked on my pretty well-set-up bass and it does the same (for a split second) - so I played around for a while and realised that with certain fret profiles it's pretty inevitable but that I'm automatically controlling it with my muting technique. If it doesn't buzz when the note's played then I can't see that altering the action or truss will get you any further than a certain point, but in the 'real world' for my playing at least it's a non-issue. EDIT: If it lasts more than a very short time though, it is set-up related.

[quote name='JMT3781' post='1050266' date='Dec 7 2010, 10:18 AM']yeah, i said i thought it was naughty, but a great idea nonetheless.. most business ideas are aren't they? someone always has to loose out i guess..[/quote] The ones who lose out are the manufacturers who don't offer courtesy amps - I'm sure a few of them will follow suit if this is successful for MB.

I have massive respect for anyone who can sing and play bass at the same time - I really struggle with it, I've managed on about two songs ever I think, though I have much less of a problem if I'm playing keys. It's the rhythm that does me, though I've not tried much on 'straighter' pop stuff. I really don't know how Larry and Bootsy do it!

[quote name='lemmywinks' post='1050117' date='Dec 7 2010, 01:26 AM']What would be the best way to bed the driver in? I would like to use this at practice on Thursday and don't want to push it until i'm sure it's ok to do so[/quote] Just feed some signal through it at medium volume with plenty of LF content. I used recorded music for a few hours on a Deltalite-loaded cab and it made a noticeable difference to the response, though it probably varies driver to driver. If you want to do it without making lots of noise, take the driver out of the cab first and wire it direct, just remember that you've got about 8mm peak-peak excursion to play with and you'll reach it at much lower power with the speaker out of the cab. Keep an eye on the cone as you turn it up though, and you'll be fine. I expect if you don't bother doing this, then as long as you don't force the cab too hard the worst thing that would happen would be slightly crappy sound for the practice.

[quote name='icastle' post='1050039' date='Dec 6 2010, 11:22 PM']Ye gods!!! Last time I saw anything that looked like that it had two electrodes and a man shouting "CLEAR"... [/quote] Am I wrong for liking that way more than the standard LMIII fascia?

[quote name='bobbytodd' post='1050002' date='Dec 6 2010, 11:00 PM']his reply the guitarist isnt as good as me[/quote] If he's too loud then he's no f***** good at music at all, no matter how fast he can run along the fretboard. Does he want to be in a band or perform as a solo act? I've done sound for players like this before, normally I find it's more a matter of psychology than knowing what's technically correct, get him onside and thinking that your idea is his idea and you'll be laughing. First the egomaniacal idiot needs to be reassured that a well-balanced sound will still let him be heard comfortably above the other instruments because he'll have frequencies where he is dominant. Second, he needs to realise that people hearing a band like this will now think 'what a great guitarist' rather than 'what a loud guitarist'. It'll really help if, when you do get it sorted with an engineer, people compliment him on his playing in the context of the band's overall sound. Especially if they are fit ladies and compare it favourably with a previous gig where he was 'so loud they couldn't hear properly'. You also have to make sure that your own sound is spot on, filling out the bottom end with a solid tone but not treading on anyone else's toes. Regarding the 'order' of loudness of instruments, this makes absolutely no sense to a sound engineer whether you're talking about live or recorded. You're not all producing the loudest part of your signal at the same time - live, the drums will always be way louder than anything else at their peak but that lasts a fraction of a second each beat, in between is when you hear the guitar etc. Plus you can have multiple sounds all loudest at different frequencies - the ability of ears to separate out different frequency sounds is why we can enjoy polyphonic music! It does sound like your guitarist is a few more tuning pegs short of a headstock even than is typical.

[quote name='fatback' post='1048477' date='Dec 5 2010, 05:49 PM']Anyone actually had an RCD trip? I've never used one, but i'm starting to think I should.[/quote] Yep, as a sound engineer loads of times. Amazing the number of hotels, pubs, clubs etc where you get dodgy sockets. Be warned though, I've also had faulty RCDs where the RCD trips on 'healthy' scokets so get a decent one. You can buy multiway extension reels with an RCD built in, very useful.

[quote name='bassatnight' post='1048227' date='Dec 5 2010, 02:03 PM']Folks, For the first time since playing Bass I have managed to break the bridge. After putting on some new strings I noticed a crack in the slot for the E string. I literally touched the crack line and it came away in my hands. I now require a new Bridge, the Bass is a Fender Jazz Fretless can anyone advise of a high quality replacement, I have seen plastic ones, Brass ones and even chrome I just don't know where to start also what size would I require? Cheers, Steve.[/quote] Stupid question maybe, but do you mean bridge or do you mean nut? I've never seen a plastic bridge for electric bass, and even the Fender bent-bit-of-tin bridge would be pretty hard to break by cracking the saddles!

2 too

[quote name='4 Strings' post='1047018' date='Dec 4 2010, 01:28 AM']Thanks all, been a great ride, I hope to continue it if I need more power and dig holes in my little Ampeg cab, and I'm really grateful for the advice.[/quote] Glad to hear it's sounding better - if you do decide you need to get the most out of this driver at the low end then I /think/ everyone would agree that, as BFM and others have said, the best way would be a slightly bigger box. The advantages are twofold - first you get extended bass response anyway from the volume increase, second you don't need such a long port to tune it. You're probably at the performance limit of a box that big at the moment and won't gain anything by changing it around further.

I am very impressed with both your basses. Well done sir!

I think it's worth listening to the original bass part on the recording of that Free number. It's very 'solid' without having a very deep bass - more low-mid punch and a bit of upper-mid clank. You can probably get a 'tighter' tone that'll fill out the sound and please the rest of the band without adding in the excessive treble you're worried about, by sorting out the mids and rolling the deep bass off a bit. It'll still be there providing nice reinforcement, but it shouldn't be the main component of a mix unless you're playing very specific genres. It might take a while to get used to as a player but it will give the band a fuller sound.