Gnome

Wow, you're still wasting time responding to this email , even AFTER I apologized for stirring trouble? Well, I guess I can waste some more time before heading to work. You still are pissed off huh? hmm 12,000+ posts. No wonder, you spend all day monitoring PG. Looks like someone needs a day job.

nice catch on the ft^2.. hotrock, oops. It's a wonder the resident genius (that would be wes) didn't pick up on that (he didn't even know what an infinite baffle was, therefore he couldn't correct me until Lovecraft made a point about it). My haste got the best of me. All of speakers I've seen are spec'd for a total ft^3 (bolded for hotrock, hehe) volume. Oh yeah, how the heck could I have spelled bass, Base??. Must have been pain from watching the Red Sox lose last night.

Spelling ability without the use of a checker has absolutely no bearing in engineering. One drop down menu in MS Word? Viola, spelling mistakes gone. A couple silly mistakes on a project guitar board?? hey I can live with that. You're the one the has get his panties in a bunch over a few spelling errors. Heck, the engineer in adjacent cube at work has Dyslexia for christ's sake, yet was able to still do pretty well for himself. Hmmm, I guess he is an idiot for making spelling mistakes often? Right?

Sorry Gorecki for helping to drag this thread through the mud... but when I hear someone rattle off an uniformed theory like "This cabinet is louder/softer/better/worse due to less/more/etc air behind a speaker" ... it makes me shudder. not to mention the oldest, sadest tactic in the book for saving face in an argument... changing the subject to focus on someone's typos and grammar mistakes.

apologies to all (gorecki, westheman, lovecraft, et al).

....Wes is implying that (rather badly I might add) that better bass response is coming from the slanted speaker due to the fact that there is "less air volume behind the speaker"....

You've lost track of the thread - Wes is stating the exact opposite.

Ok, next, as far as the infinite baffle enclosure goes (as in these cabs, or at least in the homemade cab I have here and the others Ive seen), when you have an infinite baffle there is and infinite number of ft^2 behind the speaker, hence using the same speaker in the enclosure.

Since Marshall stack cabinets are sealed cabinets, this is totally inapplicable, and you know that if you've had the training you claim - I'm forced to assume that either you are trying to win the argument at the expense of accuracy, or that you know very little about production guitar cabinets. It really doesn't matter to me who "wins", but it would be nice if Dave could get the info he was looking for without all this extraneous noise.

Lovecraft I agree about taking the thread off on a tangent, however I just explained that I've been mistyping. However, my argument holds whether you use "slanted" or "flat" in there. Winning the argument? I really wasn't trying to "win" the argument, however when Wes completely skips the argument at hand and has to resort to silly insults involving typos or my intelligence, it gets tiring. Can't come up with any arguments? Call someone an idiot and find a typo. It's such an easy 'out'.

Wes is making a "My car is fuel efficient because its color is red" argument. Every one of my arguments with qualified with either "infinite baffle" or "sealed", and it's funny you, not Wes, caught that statement.

Wes is implying that (rather badly I might add) that better bass response is coming from the slanted speaker due to the fact that there is "less air volume behind the speaker".

umm...actually i am implying the exact opposite of that are you sure you know what you are debating?

oh,and drop the first "that" in your statement

oops my apologies sorry wes, I've been mistyping this whole time. The fact remains, you're trying to argue air behind a speaker in a infinite baffle application.... same volume of air behind each.

... I found a cheap $40.00 12" Polk sub online that requires 1.8 ft^2 in a sealed enclosure. I also found a higher quality $170.00 12" alpine sub that requires 0.8 ft^2 in a sealed enclosure...

Now you're just arguing to try to save face. Bringing up Alpine subwoofers in a discussion of guitar cabinets is like bringing a knife to a gunfight. Besides, all the amp manufacturers that I've seen use the same drivers in their slanted cabs as they do in their straight cabs, which kinda makes your point moot. Wes is/was completely correct in the context of this conversation, regardless of how much smoke you blow around - might be time to cut your losses and retire from the conflict.

Hey at least someone who doesn't want to resort to personal attacks.

Saving face? I don't agree with you. Wes is implying that (rather badly I might add) that better bass response is coming from the slanted speaker due to the fact that there is "less air volume behind the speaker". I brought out the fact by using 2 examples from a crutchfield catalog I had nearby, that just because you have less air volume in a speaker enclosure, it doesn't guarantee you increased db's for any particular frequency, or across a range of frequencies for that matter. The math just doesn't work out. Btw, please explain how the science of loudspeakers differs between Marshall and Alpine? It doesn't.

Ok, next, as far as the infinite baffle enclosure goes (as in these cabs, or at least in the homemade cab I have here and the others Ive seen), when you have an infinite baffle there is and infinite number of ft^2 behind the speaker, hence using the same speaker in the enclosure. It doesn't matter whether the angle is 90 degrees or 45 degress or somewhere in between.

I'll concede that in certain soundstage setups you're going to get better bass response in a slant cab, and in others you'll get better for a flat cab setup.

"slant cab has less bass because of the lack of volume behind the speakers"

Personal attacks:

"anyway you guys have fun trying to see who is smartest,but i don't think m.e.n.s.a will be knocking your doors down trying to recruit."

What part of the statement above is not a personal attack?

"Maybe you should research a little"

Research what? The fact that you don't 'waste' your personal attacks here?

You're a funny guy. Let me guess? 15 yrs old at most? Yeah, I didn't pay attention. I didn't graduate with good grades, and I don't have a job right now employed as an engineer. Gee, my employer must have done something wrong in order to hire someone with such poor grammar.

I don't pay attention to board members? Talk about calling the kettle black. Notice how other board members didn't need to resort to "You don't know what you're taking about" in order to make their points. Not everyone has to agree here, but try to lay off the blanket statements. It's obvious you're living in a world of speculation.

Please indulge me with an explanation of your breadth of knowledge in audio/electronics/acoustics? (I've at least taken a couple of courses in it)

My Dearest Wes,

Nothing like resorting to personal attacks when you can't prove your point. Oh and attacking a few mispelled words and a few grammar errors will really help buoy your points.

So sorry to ruin your day, but I've got a BSEE from a decent university, took 2 pretty rigorous courses in Acoustics as an undergrad. Not tooting my horn, but "thems the facts". Did everything from finding TS parameters, applied acoustics, to *you guessed it* loudspeaker enclosure design. coursework ran the gamut from rigourously deriving formulas to taking measurements in an anechoic chamber. So me thinks you're outta your league in this argument. I may not remember 100% of my studies, but for the most part I'd be willing to rely on my memory versus your blanket statements. I'd try and dig up some of the math, but something tells me you're just a 14 year old kid who likes to argue and it would be way over your head.

straight cabs produce more bass than similar slant cabs

that is not a blanket statement.

there are other things that also affect the sound,such as type of wood used in a cabinet,or special baffling systems like marshall puts in their 1960 vintage cabs...but as a general rule,if all other factors are the same,slant cab has less bass because of the lack of volume behind the speakers

so now who is "just plain wrong?"

wes, "Wood type" changing the sound? that's a good one. If you believe that, I have a bridge to sell you. We're talking about guitar amp speaker cabinets projecting a relatively small band of the sound spectrum, not high-end stereo equip where it *might* make oh so bit a difference some big band jazz song comprised of the full sound spectrum. As long as the appropriate type of material is used. (i.e. a quality rigid material thick enough so that deflections/warping do not occur in the cab walls due to pressure) you could probably use any material on earth for a speaker cabinet. Won't make a damn difference in 99% of scenarios. I've seen concrete and brick used for cab building before... A speaker was designed to see a specified volume of air behind it in order to work at maximum performance. I've heard quite a few free air subwoofers (read: infinite speaker box volume) kick out better base than ported enclosures (read: improperly designed cabinet due to incorrect box volume).

"slant cab has less bass because of the lack of volume behind the speakers"

Wrong, just isn't true, the cab is designed according to a particular speaker specifications. Just because there is "lack of volume" behind a speaker doesn't automatically mean "poor base response". If you're taking about open-back cab. guess what? the slanted and straight faced woofers see the SAME amount if air behind them = infinite baffle.

To further illustrate... I found a cheap $40.00 12" Polk sub online that requires 1.8 ft^2 in a sealed enclosure. I also found a higher quality $170.00 12" alpine sub that requires 0.8 ft^2 in a sealed enclosure. If you had to lay down your money, what would you bet on to be louder and have better bass response? The one with "less volume" behind it or the cheapy?

and Maiden just to clear up my point earlier, I was referring to deep sub freqs being non directional. If youre building an angled kick panel for a 6" woofer or something, and your sending anything below, oh i dont know, say a couple hundred Hz than you're crossover is f-ed up. I wasnt speaking about mid range.

lower frequencies are non-directional, or at least 'feel' non directional. therefore speaker placement and direction of speaker are less important.

projecting mid range, and especially high frequency sound depends heavily on how the speaker is directioned.

like someone said before.. if youre playing a bar and putting your cab on the floor you may want a slanted cab to project some of the high freq up to peoples ears. if youre on a stage, a flat faced cab is fine...

btw. a blanket statement like "there is 'more base' on a straight cab" is just plain wrong.

id agree that thing is nice, but I think the knobs dont really "work"

WOW, nice stuff. You've got 2, so can I have one of them? How bout if I agree to pay for shipping?

To reply to the original idea, a small home built machine with software will cost in the area of $8,000. I can not stress this any stronger but, do not buy stuff on Ebay. Use only ballscrews and linear bearings. Servo motors are better than steppers and require less power. Use a 1 Gig or larger ram memory in your computer, g code files can be very large. Do not skimp on anything and be very precise in your constuction methods. Gnome, the best site for homebuilt cnc is

www.cnczone.com. Here you will find the best minds on the net for homebuilt cnc.

And for the young monkey, before you buy anything make one by hand first to discover your strenghths and weaknesses and go from there. A good job would help the money problems and maybe a degree in Machine Technology will help.

Thanks for the link been there many times.

as far as cost goes.. I'm $1200+ (i think, heheh). The 1200 includes a bunch of stuff i may not end up using, but the price on some of the pieces were good. I'm lucky in that I've got ProE, AutoCad 2000, and Solidworks2000, but regardless, basic toolpath software can be had for real cheap ($200-500). We're talking CRUDE functionality, but its enough for debug and basic tuning. I think $8000 is on the high side. Im aiming for $2000 for the 'first gen' machine.

I'd have to disagree about ebay. I've gotten several great deals. Patience is the key. I picked up a couple 48" ball screws and a few pillow blocks for like $100. I couldnt believe I won that auction. If you know what youre looking for and are willing to wait for things, you can find deals.

i need to get off my a** and pick up some aluminum extrusion so i can start building the frame and start mounting. its a slow process when you got a full time job and no extra time. no complaints though

I found this article just now when I searched the net to find out what "stickered" meant:

Storing Lumber

I can't vouch for the validity of the article, but it does seem to touch on a few of the points made by others in this thread.

Best Regards,

Mike.

thankx for the link, good info

'Wood' anyone really spend $100, $200, $300 on wood that they haven't actually seen in person from ebay? (sorry couldn't pass up the crappy pun)

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...3752103561&rd=1

I'm probably going bidding on some wood for my project tonight if I see anything decent.

So... As a general rule. Where should I store the wood? In my apartment, in my garage?

Don't buy Chinese metal... and look carefully at the description. Stanley has a bunch of stuff that is assemble in the USA or UK, but the metal is from China.

You can get good files for $5-15 each. And buy a wide variety of widths, shapes, tooth count, and tooth shape/pattern.

D~s

I'd agree with this 100% .. steel from China is absolute crap. CRAP.

I usually look for british stell.... sadly, american steel isnt that great now.

you get what you pay for within reason.

While I appreciate the help, since small-signal schottkys generally run less than a quarter a piece, I really don't mind buying them - what I was hoping for was some info on which ones worked best. Oh well, guess I'll just have to buy a couple of dozen pair when I get sufficiently motivated, and decide what sounds best. If anybody else gets around to it before I do, update me if you don't mind.

my message was more for javacody, than anyone else. he seemed to be ahving problems located them...

where are you guys located?

You could take a quick trip to the local university electrical engineering department. they usually have a good stock of parts for cheap for students. they probably wont even know youre not a student.

also, http://www.partsexpress.com/

Also, back when i was a student I used to email semiconductor companies and request samples for 'student projects' even though I was using them for my own projects. i got TONS of free parts. It helps to have a .edu email address I would imagine.

How about something like "Dee" by Randy Rhoads. Its not that tough, tabs are available, and its sounds really good once you master it.... and it is pretty short

Not really "lime" but green nonetheless:

http://www.timtone.com/gallery/images/RJHiRezHalfFace.jpg

thanks for the question lovekraft.  i was wondering the same thing.  and since i know you'll be checking back in i've got another little question about farads.  i found a good little tutorial explaining pico, nano and micro farads but looking in my trusty radio shack catalog i find pf and the u with the tail.  is the uf larger or smaller than the pf?

IT goes like this

Farad

millifarad (mf) 1x10^-3 = .001

microfarad (uf) 1x10^-6 = .000001

nanofarad (nf) 1x10^-9 = .0000000001

picofarad (pf) 1x10^-12 = .0000000000001

so.. uf has a higher capacitance than pf

I did a search for your posts and the result was a million pages. Is there a thread where you've posted all of your pics? I found some pics of "Bones", but thats it

...can i tap into the amps power? if i tap the amps power how do i go about doing that? i just see a bunch of wires in there...

If all you see in there is a "bunch of wires", then you probably don't need to be poking around in your amp in the first place. Sorry to sound blunt, but you can cause yourself serious personal injury if you don't know what you're doing, not to mention destroying your amp. It's not like case modding, where everything is modular and designed to be reconfigured. You'll have to have some basic electronics know-how to identify where to tap into the amp's power supply without damaging anything. I strongly recommend you learn a little more about how electronics works before risking your amp and your health - or have the amp modded by a qualified technician.

haha, youre probably right... you have to know what youre looking for or else your going to end up getting zapped. .. for that matter even when your amp is unplugged for that matter, you still can get nailed if you go poking around caps and what not.

i think you need to first thinking about gettting a wider neck. which youll need to buy, unless you can come up with some crafty way to widen your existing neck.

im sure some of the more experienced people on here can give you some caveats.

http://projectguitar.ibforums.com/index.php?showtopic=11365

you may find some info here... maybe not