LawrenceH

Worth considering something with a graphite neck, no?

[quote name='MoonBassAlpha' post='1319906' date='Jul 28 2011, 11:52 PM']Is that a big problem if you also have a tweeter, as in the picture?[/quote] It is if you like mids in your sound. Instant smiley face graphic for those who like that though.

All this stuff about the load being more on the strap if you move it further down is incorrect, and the science behind what's actually involved is very simple. It's about the centre of mass around a pivot point. In this case the pivot point is on the strap, at the point where the load is balanced equally. Assuming the strap is free to travel along the pivot point, the point of equal loading is dependent on the anchor points of the strap relative to the object being suspended. To make it clear which way this works, consider the extreme cases of a bass with an infinitely small distance between anchor points - ie suspended from the bridge end alone or from the horn alone. Pretty obviously, a bass suspended from the bridge alone has the worst neck dive possible (pointing at the floor). So Ou7hined is basically correct, apart from a few special cases with unusual body contours. But, if the horn strap pin isn't sufficiently neck-wards, even suspending from that alone will still leave the centre of mass too far up the neck. In those cases altering the bridge strap pin won't help much either way. Having said all that...this simple model makes the assumption that the strap is free to slide around the pivot point. In actual fact, there is considerable friction between the strap and the player's body, plus the player's body gets in the way of the instrument preventing it hanging freely and probably takes some of the weight. If less of the weight is taken by the player's body eg because you alter the strap position so that the guitar hangs at a different front-back angle, then it will improve neck dive, potentially even if that move takes the pin the other way to normal.

[quote name='lanark' post='1319071' date='Jul 28 2011, 10:18 AM']Well, it's accepted that Stradivarius used crap wood that instrument makers would nowadays rather burn than make an instrument from. Guess what, the explanation for the tone moves from wood, to the "special" glue or varnish or something, whatever. It can't just be that he was exceptionally good at making instruments and that the magic comes from a) the maker's skill and b ) the listener's brain *after* being told it's a Strad.[/quote] Well no, the magic can't come from the maker's skill because it's not actual magic, the skill has to have resulted in some physical property of the instrument. Psychological effects are almost definitely involved as well, but it's not like all Stradivari sound brilliant and every other violin total arse, its just that good violins sound incredibly different from bad ones. But a braced hollow structure like a violin is incredibly different to a solid body guitar. People often misinterpret that to mean that wood is more important for the acoustic instrument, but actually what it means is the structure as a whole is more important - of which wood type is just a part, hence the importance of bracing. Shape of a solid body instrument within reasonable boundaries is by comparison much less critical. As far as I can see, this discussion always goes on and on for 3 reasons (not pointing the finger at anyone in particular, just an observation of what always happens). First, insufficient grasp of the physics involves. Second, insufficient understanding of how to formulate a scientific hypothesis and test it. Third, insufficient understanding of statistical analysis to interpret results. The second reason is the most insidious IMO, because people often end up at loggerheads when really they'd probably agree on the evidence, just interpret the question differently.

[quote name='Mr. Foxen' post='1318791' date='Jul 27 2011, 10:23 PM']Trace already did stuff with front resonant chamber:[/quote] I wondered if these would get a mention. Bit of an oddity in the bass guitar world, and I recall them polarising opinion a fair bit too! Neat idea though, 4th order bandpass but a port that radiates directly and modifies directivity at the same time. Scoop city when you fired them up, it wasn't very hifi! The contribution of chamber resonance to the output of a foam blocked cab is by comparison going to be negligible by guitar/bass cab standards though...

[quote name='Bill Fitzmaurice' post='1318471' date='Jul 27 2011, 05:35 PM']Yes, though while it seems the opposite of the beam blocker it isn't. It's just two different implementations of the same phenomena.[/quote] That really depends on the foam used. This 1" thick auralex foam has absorption coefficients approaching 1 above 2000Hz. [url="http://www.auralex.com/testdata/test/1wedge.pdf"]http://www.auralex.com/testdata/test/1wedge.pdf[/url] A good acoustic foam at even 1/2" will absorb energy more than reflect or diffract in the mid-high frequencies giving a very worthwhile reduction in output, while as Bill says being essentially transparent at low frequencies. In those cases that image is a good visualisation for a single high frequency wave.

[quote name='Marvin' post='1318382' date='Jul 27 2011, 03:52 PM']Unfortunately the detractors, of what is somewhat basic acoustic engineering, put up little in response apart from to say they're talking rubbish because no one else builds cabs like that.[/quote] Lots and lots of people and companies build cabinets like the BF ones, ie reflex boxes. A fair number of manufacturers in the PA world have also build horn-loaded cabinets like the BFM designs. Their strengths and limitations are pretty well characterised - I built a set of Jack 10s, measured them and while I was at it modelled the design in software. The design behaved as the software predicted.

[quote name='cytania' post='1317680' date='Jul 26 2011, 09:45 PM']Somewhere out there I remember a research picture of the resonant parts of an electric guitar and the body hardly vibrates at all compared to the neck. So these experiments with lumber are revealing that in a sense the body and the body/neck joint are as much a damper as they are a resonator. Clearly the lumber used was part of the mid-spectrum of useable woods between the balsa/leadwood poles.[/quote] This is really interesting...after much swapping of pickups, necks, bodies, tapping of woods and pondering I have come to the conclusion that the role of the neck is a bit under-appreciated and would probably look to change that before body wood if I wanted to make tonal alterations.

[quote name='EdwardHimself' post='1317726' date='Jul 26 2011, 10:24 PM']but I think it sounds pretty good. Of course i've never tried a barefaced or bill fitzmaurice cab before so for all I know it might be totally rubbish.[/quote] That's because it is, the B&C drivers used are very capable indeed and the cab I've seen inside used decent wood. Some people don't seem to like the character of the sound but that's neither here nor there really.

[quote name='Bill Fitzmaurice' post='1317393' date='Jul 26 2011, 05:50 PM']Maybe. An alternative view is that the hole becomes the primary radiating plane for high frequencies, and as its diameter is small the dispersion is widened.[/quote] But that's not an alternative view that is what was described in the original link and by me. Hence the existence of a hole is essential for the design. [quote name='Bill Fitzmaurice' post='1317393' date='Jul 26 2011, 05:50 PM']The same mechanism is seen in slot loaded tweeters, which also make the slot narrow and high, for both wide horizontal dispersion and tight vertical pattern control. It's an easy enough theory to test, you just make a foam plate with a narrow high slot instead of a hole and measure it on both axis.[/quote] Yes, I nearly wrote that before actually but thought that since a lot of slot tweeters are designed with horns/waveguides as well it confuses things. Anyhow a slot design is fine if you want narrow vertical distribution, but for the Beam of Death (which was why I brought up those foam things in the first place), I'd say it's better to have a more uniform dispersion to get it in the guitarist's ears!

[quote name='Mr. Foxen' post='1316945' date='Jul 26 2011, 01:00 PM']I've already read it, and the dissection of it with various engineers, including BFM. Just because something works doesn't mean that the explanation of why it works is true.[/quote] Wave transmission through an aperture at different wavelengths relative to the aperture width is secondary school physics, and pretty easy to visualise graphically. The problem in description is not in the foam donut but on the misconception where circular beam blockers are described as 'blocking' a 'beam' from the cone, when there is no such beam but instead a central point of symmetry where wave summation is maximally coherent. They actually 'work' by reflecting and as BFM has said diffracting the sound waves. The acoustic foam certainly does attenuate at higher frequencies as illustrated by the NRC for good quality 1/2" to 3/4" foam, and a model based on simple absorption predicts well what is observed in practice. The hole is entirely necessary - covering the whole speaker in a uniform layer of foam would do nothing to alter directivity, it would merely attenuate the overall output. Graded density foam can be used to act as a waveguide but that is relying on wave propagation through the foam and far greater thicknesses are required, ie a stuffed horn, to give sufficient distance for the induced delay to alter directivity appreciably. This however is a refractive effect - as explained on one of Geddes' own patents for a stuffed waveguide. Foam stuffing is also used to absorb sound in waveguides/horns, which [i]corrects[/i] for [i]problems[/i] introduced by diffraction. It is not a diffractive effect in its own right.

[quote name='Bill Fitzmaurice' post='1316462' date='Jul 25 2011, 11:22 PM']I think you'd find adding a beam blocker to the hole in that foam thingamajig would get a better result than either alone. The blocker probably works better than the foam if sized properly. I doubt that Weber ever did a thorough study of different sizes and shapes. I might someday if I have nothing else to do, it would only take an hour or so to map polars with different size blockers in different positions.[/quote] Careful, or you'll reinvent the phase plug With flat reflective blockers though you'll create a horrible mess of variable HF path lengths. With a theoretical totally absorptive round flat blocker you will create a ring-shaped aperture which will give quite a strange diffraction pattern at high frequency but do very little other than a small reduction in volume in the mids and lower. In the context of the foam donut thing, the opposite edges of the loudspeaker cone are no different to two smaller spaced drivers, with the same solution presenting itself ie get them closer together.

[quote name='Bill Fitzmaurice' post='1316393' date='Jul 25 2011, 10:11 PM']Not if you do it right, which is with varying foam thickness across the cone. See the Geddes model. The amount of attenuation offered by 3/4 inch of foam is infinitesimal. The diffraction is fairly significant at the shortest wavelengths, enough to cause them to literally bounce off the walls of the foam's individual cells, redirecting their paths, while longer wavelengths pass though unimpeded.[/quote] Sigh...but the Geddes model is considerably more expensive to implement. For all intents and purposes in the frequencies where guitars output this model works by attenuation, and 3/4" of the right stuff is enough to make a worthwhile (ie audible) difference that can be confirmed by measurement directivity plots without creating a bloody great waveguide that adds volume to the cabinet. The main drawback is an overall loss of sensitivity in the HF but you gain a less uneven dispersion pattern. By contrast a 'beam blocker' creates a more complex pattern that when you measure it is all jagged and unven. Doesn't really go towards solving the problem so much as shift it about. You do like to be difficult sometimes Bill!

[quote name='Bill Fitzmaurice' post='1316285' date='Jul 25 2011, 09:15 PM']It works, but isn't at all a new or novel idea. Earl Geddes has been using foam for quite some time, and without a hole in the middle, as that's not what makes it work. The underlying principle is diffraction; a thirty year old example is the JBL 2301 perforated plate horn lens. [url="http://www.jblpro.com/pub/obsolete/acoustic_lens_family1.pdf"]http://www.jblpro.com/pub/obsolete/acoustic_lens_family1.pdf[/url] Beam blockers use the same principle.[/quote] I didn't claim it was new or novel - just that it works and is quite neat - that one happens to be a good cheap implementation. But in that design the hole in the middle IS what makes it work, otherwise you just attenuate the sound without modifying directivity. The foam with hole is just an HF absorber to reduce effective cone diameter. Some of the designs use different density foams to alter the speed of sound through the material at different points to make a waveguide but that's not what's going on here. EDIT - oh yeah and a standard beam blocker doesn't use the same principle at all as it doesn't work, at 'blocking' the beam that is

[quote name='Bill Fitzmaurice' post='1316341' date='Jul 25 2011, 09:36 PM']More than a few top acts don't have any amps on stage at all. They still have them, backstage. They hear what the audience hears, the PA feed, though both monitors and in-ears. 'Journey' adopted this arrangement at least 12 years ago. Geddy Lee is probably the most obvious proponent. Chicken, anyone?[/quote] Yes and it'll become more and more common for larger acts I think - you need bloody awesome monitoring to pull it off though, way beyond what's 'average' in the UK and it still doesn't sound the same on stage. One functions band I used to do sound for went down this route, but in the end they were never satisfied with the stage sound and regressed back to big amps (sigh)! I suppose those same limitations inherent in a big stack also contribute to a unique stage sound.

[quote name='thodrik' post='1316257' date='Jul 25 2011, 09:00 PM']They see something that looks like a Fender and when it doesn't handle or sound like one, they go away disappointed and dismiss the bass as average/generic/rubbish.[/quote] Yeah this is definitely part of it. Though that's fair enough given what it looks like and Sadowsky's pedigree in the world of Fender repairs/mods! If they had a custom shape then even with the exact same pickup configs then people would see them as different. But, sound-wise, I honestly haven't heard anything that would distinguish their own 'signature' sound as distinct from any old jazz with aftermarket pickups/pre.

[quote name='ficelles' post='1316280' date='Jul 25 2011, 09:11 PM']I sense a beam blocker discussion approaching... ficelles[/quote] Oh dear, I hope not! Because they clearly don't work as designed... Mr Foxen, what I mean is that the problem of the guitarist not hearing himself is more down to the fundamental limitations/directivity of a single large diameter speaker than the comb filtering effect from stacks. Even if your stack is set vertically the sound will be highly directive just due to the speaker. Btw vertical stacks will still comb filter, just in one plane - but audience members at different heights will get just as different a sound as those in different positions around a horizontal stack. Vertical stacking is not an ideal solution and in, say, theatres or any gigs with balconies then it will actually be more problematic. Bill makes a very fair point that guitar stacks are overkill and a single speaker would do the job, though personally I think they like them not just for the look but the nearfield sound on stage (very full, bass-heavy and a PITA to mix). You just don't get that with a 1x12".

[quote name='Mr. Foxen' post='1315993' date='Jul 25 2011, 05:33 PM']No, Fender didn't make tall stacks, they made short combos, and guitartists tend to sit on them or stand in front of them, so all the top end misses them and icepicks anyone in front..[/quote] That has more to do with the fundamental limitations of 12" speakers than eg the small advantage gained by crossfiring. I'm a big fan of angling speakers back on stands to get the guitardist's ears closer to the 'beam of death' but a neater solution (IMO) is Jay Mitchell's 'foam donut' [url="http://www.stratopastor.org.uk/strato/amps/prii/speaker/foamdonut/foamdonut.html"]http://www.stratopastor.org.uk/strato/amps.../foamdonut.html[/url] Dead simple to implement and the beauty is you can tailor the foam type/thickness and size of the hole to give some flexibility to freq cutoff and amount of attenuation.

I like mine at the correct height... which is high shame it looks so silly

[quote name='thodrik' post='1316203' date='Jul 25 2011, 08:24 PM']Personally, I can't don't like Warwick basses. However every time a thread opens up about Warwicks and I do not feel the urge to tell the story about that one time I tried a Thumb and a Streamer in a shop and didn't like them, which of course means that all Warwicks are overpriced, have uncomfortable necks and deliver a distinctly underwhelming sound compared to what I was actually expecting![/quote] I think it's because a Warwick is it's own thing whereas a Sadowsky is a take on another well-known bass, so there's more of a direct comparison to make

[quote name='loudandclear' post='1316173' date='Jul 25 2011, 08:00 PM']If I bought a bass that sounded woolly I would take it back ![/quote] But it wasn't woolly, it was woody.

Sadowsky's certainly sound pretty 'average' to me...I'm sure they play nicely and all that but they just sound like another modern take on a jazz bass. I've only heard one Sandberg in the flesh, but it had more of a woodier, individual sound to my ears.

Well adding more weight to the bridge end of the body will definitely work, it's just a question of how much weight you have to add. The further you get that weight out from the centre of gravity around which the bass is pivoting, the less you will need cos it'll have more leverage. A good place to start might be to hang kitchen weights from the bridge strap pin and see just how much you need to bring it up to an acceptable position.

[quote name='skej21' post='1315833' date='Jul 25 2011, 03:33 PM']Having read through the thread, this is the part that sticks out. You appear to be putting in the practice time, but if your pinky is "dead weight" and you need to go out of your way to focus your practice to include it, I would suggest your technique is not good enough to allow you to get what's in your head out on to your fingers. If I was you, I'd practice technical/fingering exercises and get a teacher to help you rectify your technique. If your technique was right, you'd be using your pinky all the time when playing and once you get this sorted out, you'll be flying! Like you said, some days you'll nail it and some days it feels like you're making it difficult for yourself. The chances are that if your technique isn't great and you're not using your pinky, you actually are making it more difficult for yourself.[/quote] To me it stands out partly because too often people focus on left hand technique when the right hand is actually the thing that's the limiting factor. Trying to play lines slowly at first in isolation, looking at how your hands move and pinpoint the problem areas, is invaluable. You should also try and think about how you play when practicing compared to with the band - do you try and play harder to match the volume? I know I do, and if I'm hammering the strings it means I can't play as cleanly. All this advice on not overplaying is very important, but it is a separate issue to a problem with technique. Sorting out the latter doesn't do any harm to the former, on the contrary it really helps everything.

I ran my SR500 (both with the stock pickups and the Nordstrand Big Singles) active and passive wired VVT like a standard jazz. The difference between active (but flat) and passive was subtle - very subtle indeed with the Barts, bit more obvious with the Nordstrands but still the same fundamental non-Fender sound. But I have just remembered that if you look at the SR series with soapbar pickups from the last few years, the pickup position has shifted. Mine (2003/4 model?) had them both closer to the bridge than later versions. If the current ones have them closer to what you'd get on a jazz/P then you may find you get closer to the tone you want. My Aerodyne (basswood) is pretty light, something like that, perhaps kitted out with ultralite tuners, might do the job and would give you the sound you're after.