Bass guitar cabinet design

[groovatism]

I'm in the preliminary planning stage for 2 bass guitar cabinets. Each will have a 15" speaker (which I've already purchased) in a sealed cabinet. Running the numbers, the cabinet will need to be 6 to 6.5 cubic feet (unstuffed), which is a bit large, but fine.

They will be made of 1" plywood, using ripped 2x4s to cleat all of the inside edges, to middle-brace each panel, and to provide front-to-back, top-to-bottom, and side-to-side bracing. They will be "glued & screwed", for transporting stability.

For the baffles, I will do the regular speaker cutout, but then I'm going to laminate a piece of 1/4" plywood to it, cutting a circle in it, slightly larger than the diameter of the speaker (more on this - read on), before I put them together. This will strengthen the baffle, plus provide flush-mounting without routing. Once the speaker is installed, I'll stretch black speaker cloth over the speaker, and attach it by using piping between the edge of the speaker and the 1/4" plywood cutout, using small brass screws to help secure the piping. This will provide physical protection of the speaker, retaining the flush-mount status. This will be necessary because, unlike typical instrument cabinets, there will be no overhang of the sides, top, and bottom, past the baffle, nor past the rear panel.

All edges will be radiused 1/2", and the cabinets will be covered in snakeskin naugahyde.

All hardware will be black. They'll have metal corner protectors, metal cup-style side handles (like on a Marshall cabinet), large rubber feet, and pop-in/pop-out casters.

The only electrical connection will be a 1/4", gold-plated jack, which will be in the middle at the top of the back of the cabinet. The jack will reside in a 4" x 4" wooden box inside the cabinet, so that there will be no air leakage through the jack (I'll caulk-seal it, where the speaker cable enters the little box).

ALL THAT BEING SAID...I still have two problems:

The First Problem: The shape of the cabinets. I have two completely different dimension options, both of which I've been given expert advice to use.

The first option is to use the golden ratio: .6 x 1 x 1.6, mounting the speaker centered horizontally (the "1" dimension), and about an inch from the top vertically (the "1.6" dimension). This design is to theoretically minimize standing waves and turbulence problems within the cabinets. However, an expert told me that those benefits, in a sealed cabinet, are out-weighed by diffractional problems outside the cabinet using this design methodology, even when employing a flush-mounted speaker on a baffle with radiused edges.

The second option (which that same expert suggests I use) is to make the cabinets 18"H x 18"W, and then as deep as I need them to provide the proper cabinet volume.

The Second Problem: Stuffing. I did a lot of Google-searching regarding stuffing, yet found nothing to specifically help me in this particular situation. Here are some of the things I found, but as we all know, most information on the internet is misinformation, or peoples' unsupported opinions...

* "Stuffing a cabinet makes the speakers think they are in a box which is approximately 20% larger." However, this person did not specify if this 20% figure is in a heavily-stuffed cabinet, or lightly stuffed. He also did not say if this holds true in EVERY cabinet type; sealed, vented, ported, isobaric, et cetera. He also did not specify which TYPE of stuffing yields this result. It stands to reason that different amounts, types, and densities of stuffing will have very different effects on the speakers' perception regarding the volume of the cabinet. Correct knowledge of this phenomenon is imperative before starting design of the cabinet, as it will drastically alter the required size of the cabinet.

* Regarding stuffing guitar and bass guitar cabinets, I read SO many conflicting opinions and results. Some say that stuffing deadens the sound undesireably, and makes the midrange dull and lifeless. Others say their cabinet sounded awful until they "packed it tightly" with stuffing. Some bass guitar cabinet manufacturers use no stuffing, some use a layer of stuffing attached to all insides surfaces, some use a layer of stuffing on half of the inside surfaces, and then some stuff them completely.

* One site gave (IMO) the best description of properly stuffing a cabinet. My understanding of his method is that you must calculate the cabinet size to be close to what it must be with it's stuffing, then adjust (fine-tune) the exact amount of stuffing (once the cabinet is assembled) according to frequency response, impedence effect on the speaker, and (of course) your ears. However, as all other experts, he did not go into the most important aspects of how to carry-out his methodology:

* How do you know, with reasonable accuracy, approximately how much stuffing will finally be used? How do you calculate where your "starting point" with the stuffing will be, with which to "fine tune" from? This knowledge is imperative, as I said before, as the properly calculated amount of stuffing to be used greatly impacts the cabinet size.

* He stated that "fine-tuning" the stuffing is accomplished using the factors of frequency response, impedence, and your ears. My foresight tells me that these three factors will somewhat conflict. Logic dictates that this will be a give-and-take situation, and that this will be a balancing act, but it DOES make sense. My take on this procedure is that, in the end, the ears will be the final judge. If it sounds right, the other two factors are probably going to naturally fall into line. I may be totally wrong, but that reasoning makes sense to me.

I apologize that this post is rather long, but I know that if I give as much information as possible, I stand the chance of getting the best help. Expert help is desperately needed at this point, and I will be very grateful for it. In particular, information regarding stuffing, in regards to the primary stages of speaker cabinet design, is virtually non-existent. With expert participation in this thread, it may indeed become a great resource for others in the same position, which I assume is a LOT of people.

Thanks, in advance, for your help and participation.

Sincerely,
A "Baffled" Builder

[rone]

Pardon me if I am a bit blunt, but none of this stuff really matters much for a PA cabinet.

As far as dimensions go, you are better off going with a standard width to match your head unit or other equipment.

As far as rounding or flush mounting, your 15" will be so directive at high frequencies that very little will reach the baffle or edges anyway, and a 1/2" roundoff won't help for the frequencies that do.

As far as stuffing goes, there is no "best" way - the final judge is your ears. REALLY bad resonances might show up in the impedance curve, but there is no magic impedance curve to look for. You might prefer the sound with lots or no stuffing, there is no way to tell except trying.

Consider using some hardware cloth to protect the woofers. Vinyl looks good new, but it will show scuffs and scratches very well, you might consider using "Rat Fur" instead.

1" walls are overkill IMO and are more likely to give you a hernia than anything else - look at high quality PA equipment and see what it is made of -

good luck, I'll buy stock in advil now....

[unknownuser]

you're going to have to find some roadies to lug that sucker around. most bass cabs even high end ones like ampeg eden and SWR are 1/2 to 3/4 ply .
I would reconsider your building materials. I'd also suggest ported for an instrument cab especially bass. you can get basicly flat all the way to the lowest frequencies a bass, even 5 string, with ported design. if you are going sealed to try and get more punch you will probably be disappointed. for punch 4 10"s is the way to go or a traditional stack of a single 15 and a 4 x 10 as a compromise.
2 15's are going to give you that reggae bass sound lots of low end and very little mid detail
it may even sound kinda muddy.
I would suggest trying a bunch of cabs out at guitar center or similar and trying to reproduce the one you liked the sound of best. it will likely be cheaper and you can customize as you like, say wrapping them in purple shag :-) rather than the standard carpet type fabric
good luck, let us know what you decide

> I'm in the preliminary planning stage for 2
> bass guitar cabinets. Each will have a
> 15" speaker (which I've already
> purchased) in a sealed cabinet. Running the
> numbers, the cabinet will need to be 6 to
> 6.5 cubic feet (unstuffed), which is a bit
> large, but fine.

> They will be made of 1" plywood, using
> ripped 2x4s to cleat all of the inside
> edges, to middle-brace each panel, and to
> provide front-to-back, top-to-bottom, and
> side-to-side bracing. They will be
> "glued & screwed", for
> transporting stability.

> For the baffles, I will do the regular
> speaker cutout, but then I'm going to
> laminate a piece of 1/4" plywood to it,
> cutting a circle in it, slightly larger than
> the diameter of the speaker (more on this -
> read on), before I put them together. This
> will strengthen the baffle, plus provide
> flush-mounting without routing. Once the
> speaker is installed, I'll stretch black
> speaker cloth over the speaker, and attach
> it by using piping between the edge of the
> speaker and the 1/4" plywood cutout,
> using small brass screws to help secure the
> piping. This will provide physical
> protection of the speaker, retaining the
> flush-mount status. This will be necessary
> because, unlike typical instrument cabinets,
> there will be no overhang of the sides, top,
> and bottom, past the baffle, nor past the
> rear panel.

> All edges will be radiused 1/2", and
> the cabinets will be covered in snakeskin
> naugahyde.

> All hardware will be black. They'll have
> metal corner protectors, metal cup-style
> side handles (like on a Marshall cabinet),
> large rubber feet, and pop-in/pop-out
> casters.

> The only electrical connection will be a
> 1/4", gold-plated jack, which will be
> in the middle at the top of the back of the
> cabinet. The jack will reside in a 4" x
> 4" wooden box inside the cabinet, so
> that there will be no air leakage through
> the jack (I'll caulk-seal it, where the
> speaker cable enters the little box).

> ALL THAT BEING SAID...I still have two
> problems:

> The First Problem: The shape of the
> cabinets. I have two completely different
> dimension options, both of which I've been
> given expert advice to use.

> The first option is to use the golden ratio:
> .6 x 1 x 1.6, mounting the speaker centered
> horizontally (the "1" dimension),
> and about an inch from the top vertically
> (the "1.6" dimension). This design
> is to theoretically minimize standing waves
> and turbulence problems within the cabinets.
> However, an expert told me that those
> benefits, in a sealed cabinet, are
> out-weighed by diffractional problems
> outside the cabinet using this design
> methodology, even when employing a
> flush-mounted speaker on a baffle with
> radiused edges.

> The second option (which that same expert
> suggests I use) is to make the cabinets
> 18"H x 18"W, and then as deep as I
> need them to provide the proper cabinet
> volume.

> The Second Problem: Stuffing. I did a lot of
> Google-searching regarding stuffing, yet
> found nothing to specifically help me in
> this particular situation. Here are some of
> the things I found, but as we all know, most
> information on the internet is
> misinformation, or peoples' unsupported
> opinions...

> * "Stuffing a cabinet makes the
> speakers think they are in a box which is
> approximately 20% larger." However,
> this person did not specify if this 20%
> figure is in a heavily-stuffed cabinet, or
> lightly stuffed. He also did not say if this
> holds true in EVERY cabinet type; sealed,
> vented, ported, isobaric, et cetera. He also
> did not specify which TYPE of stuffing
> yields this result. It stands to reason that
> different amounts, types, and densities of
> stuffing will have very different effects on
> the speakers' perception regarding the
> volume of the cabinet. Correct knowledge of
> this phenomenon is imperative before
> starting design of the cabinet, as it will
> drastically alter the required size of the
> cabinet.

> * Regarding stuffing guitar and bass guitar
> cabinets, I read SO many conflicting
> opinions and results. Some say that stuffing
> deadens the sound undesireably, and makes
> the midrange dull and lifeless. Others say
> their cabinet sounded awful until they
> "packed it tightly" with stuffing.
> Some bass guitar cabinet manufacturers use
> no stuffing, some use a layer of stuffing
> attached to all insides surfaces, some use a
> layer of stuffing on half of the inside
> surfaces, and then some stuff them
> completely.

> * One site gave (IMO) the best description
> of properly stuffing a cabinet. My
> understanding of his method is that you must
> calculate the cabinet size to be close to
> what it must be with it's stuffing, then
> adjust (fine-tune) the exact amount of
> stuffing (once the cabinet is assembled)
> according to frequency response, impedence
> effect on the speaker, and (of course) your
> ears. However, as all other experts, he did
> not go into the most important aspects of
> how to carry-out his methodology:

> * How do you know, with reasonable accuracy,
> approximately how much stuffing will finally
> be used? How do you calculate where your
> "starting point" with the stuffing
> will be, with which to "fine tune"
> from? This knowledge is imperative, as I
> said before, as the properly calculated
> amount of stuffing to be used greatly
> impacts the cabinet size.

> * He stated that "fine-tuning" the
> stuffing is accomplished using the factors
> of frequency response, impedence, and your
> ears. My foresight tells me that these three
> factors will somewhat conflict. Logic
> dictates that this will be a give-and-take
> situation, and that this will be a balancing
> act, but it DOES make sense. My take on this
> procedure is that, in the end, the ears will
> be the final judge. If it sounds right, the
> other two factors are probably going to
> naturally fall into line. I may be totally
> wrong, but that reasoning makes sense to me.

> I apologize that this post is rather long,
> but I know that if I give as much
> information as possible, I stand the chance
> of getting the best help. Expert help is
> desperately needed at this point, and I will
> be very grateful for it. In particular,
> information regarding stuffing, in regards
> to the primary stages of speaker cabinet
> design, is virtually non-existent. With
> expert participation in this thread, it may
> indeed become a great resource for others in
> the same position, which I assume is a LOT
> of people.

> Thanks, in advance, for your help and
> participation.

> Sincerely,
> A "Baffled" Builder



(Originally posted by: jim)

[groovatism]

> Pardon me if I am a bit blunt, but none of
> this stuff really matters much for a PA
> cabinet.
> As far as dimensions go, you are better off
> going with a standard width to match your
> head unit or other equipment.
> As far as rounding or flush mounting, your
> 15" will be so directive at high
> frequencies that very little will reach the
> baffle or edges anyway, and a 1/2"
> roundoff won't help for the frequencies that
> do.

> As far as stuffing goes, there is no
> "best" way - the final judge is
> your ears. REALLY bad resonances might show
> up in the impedance curve, but there is no
> magic impedance curve to look for. You might
> prefer the sound with lots or no stuffing,
> there is no way to tell except trying.

> Consider using some hardware cloth to
> protect the woofers. Vinyl looks good new,
> but it will show scuffs and scratches very
> well, you might consider using "Rat
> Fur" instead.

> 1" walls are overkill IMO and are more
> likely to give you a hernia than anything
> else - look at high quality PA equipment and
> see what it is made of -

> good luck, I'll buy stock in advil now...

Well, as you said, pardon me if I'm a bit blunt, but that was some the worst, most innaccurate advice I could have hoped for. You obviously did not read my thread with any thought. You didn't even notice that the thread is called BASS GUITAR CABINET DESIGN. You are dead WRONG regarding flush mounting and cabinet defraction, and obviously have absolutely NO knowledge whatsoever on the subject. As far as 1" plywood being overkill, again you are dead wrong. This is a bass guitar cabinet. The more rigid it is, the better it will sound, and the better it will hold-up to transporting. As far as "hardware cloth", again, if you had read my post carefully, you would have noticed that I did say that the speakers will be covered with black grill cloth. As far as using "rat fur", which also happens to be my name for that cheesy garbage, I wouldn't dream of putting that stuff on my work. I have a '65 Bandmaster that's still gorgeous (vinyl covered, of course)... it's all in how well you care for your gear. And a as far as looking at mainstream manufactured equipment ... pffft ... that's why I'm making my own.

Again ... are there any EXPERTS out there who can help? I'm not looking for uneducated opinions regarding my endeavor ... I simply need answers to the two dilemmas I am faced with.

PS ... I really am sorry if this was harsh, but I did ask for EXPERT advice, not the opinionated ramblings of those whom are ignorant of the subject. This poster didn't even take the time to thoroughly read the post.

[groovatism]

> you're going to have to find some roadies to
> lug that sucker around. most bass cabs even
> high end ones like ampeg eden and SWR are
> 1/2 to 3/4 ply .
> I would reconsider your building materials.
> I'd also suggest ported for an instrument
> cab especially bass. you can get basicly
> flat all the way to the lowest frequencies a
> bass, even 5 string, with ported design. if
> you are going sealed to try and get more
> punch you will probably be disappointed. for
> punch 4 10"s is the way to go or a
> traditional stack of a single 15 and a 4 x
> 10 as a compromise.
> 2 15's are going to give you that reggae
> bass sound lots of low end and very little
> mid detail
> it may even sound kinda muddy.
> I would suggest trying a bunch of cabs out
> at guitar center or similar and trying to
> reproduce the one you liked the sound of
> best. it will likely be cheaper and you can
> customize as you like, say wrapping them in
> purple shag :-) rather than the standard
> carpet type fabric
> good luck, let us know what you decide

I am aware that most manufacturers use 3/4" plywood, but yet others use 3/4" MDF, which is actually heavier than 1" plywood. I think you may have misunderstood my post ... this is to be TWO 1x15 cabinets, not a singular 2x15 cabinet, so they will not be all that heavy.

I have tried darn-near every bass guitar cabinet on the market, for the past 35 years. I am going with the sealed cabinet because I do not like the sound of ported cabinets for bass guitar. If you had ever heard a well-designed sealed bass guitar cabinet, with the proper speaker for the application, you would understand why. They have a very tight, yet very DEEP low end, not in the least bit muddy, but rather they are extremely articulate. In a sealed cabinet, the low-end rolloff is much more gradual than a ported cabinet. The sound is absolute bass-players' bliss. As far as top end, that is being handled in a separate cabinet, with four 6" speakers.

I'll pass on the purple shag

[chadg]

Provided Link: http://chadgray.info/


You need to get a hold of Dave Tenney. He is a bass head. Stand up bass, electric etc. He built a bass cabinent called Tuba 24. I dont think he has it on his web site.

<A HREF="http://www.wadsnet.com/~dtenney/">http://www.wadsnet.com/~dtenney/</A>

[unknownuser]

two separate cabs does sound a lot lighter . a friend of mine had a 2 x 15 and i cringe just thinking about having to move that beast around. it was covered in purple vinyl with stuffing underneath and looked very funkadelic , like a shiny rectangular purple coach
as for stuffing, i think the previous suggestion of adding and subtracting until you get the sound youlike best is very valid. buy a big box of poly fill and start by perhaps covering the rear wall and then add a bit more and see how the sound changes. the "right" amount of stuffing seems to be a very subjective thing and also can depend on the specific drivers in question. I personally would lightly staple a couple inches to the back top bottom and sides and then add a bit at a time and see what i liked the best. alternately you could line the box with acoustic foam
i too plan on building a bass cab in the near future and will be building a sealed single 18 to go biamped with my 4x10
in my case i am just matching dimensions to my 4 x10 and adjusting depth to make the correct volume. though i don't plan on purple shag either :-p .but the endless options with diy are what make it so much fun

> I am aware that most manufacturers use
> 3/4" plywood, but yet others use
> 3/4" MDF, which is actually heavier
> than 1" plywood. I think you may have
> misunderstood my post ... this is to be TWO
> 1x15 cabinets, not a singular 2x15 cabinet,
> so they will not be all that heavy.

> I have tried darn-near every bass guitar
> cabinet on the market, for the past 35
> years. I am going with the sealed cabinet
> because I do not like the sound of ported
> cabinets for bass guitar. If you had ever
> heard a well-designed sealed bass guitar
> cabinet, with the proper speaker for the
> application, you would understand why. They
> have a very tight, yet very DEEP low end,
> not in the least bit muddy, but rather they
> are extremely articulate. In a sealed
> cabinet, the low-end rolloff is much more
> gradual than a ported cabinet. The sound is
> absolute bass-players' bliss. As far as top
> end, that is being handled in a separate
> cabinet, with four 6" speakers.

> I'll pass on the purple shag



(Originally posted by: jim)

[groovatism]

> two separate cabs does sound a lot lighter .
> a friend of mine had a 2 x 15 and i cringe
> just thinking about having to move that
> beast around. it was covered in purple vinyl
> with stuffing underneath and looked very
> funkadelic , like a shiny rectangular purple
> coach
> as for stuffing, i think the previous
> suggestion of adding and subtracting until
> you get the sound youlike best is very
> valid. buy a big box of poly fill and start
> by perhaps covering the rear wall and then
> add a bit more and see how the sound
> changes. the "right" amount of
> stuffing seems to be a very subjective thing
> and also can depend on the specific drivers
> in question. I personally would lightly
> staple a couple inches to the back top
> bottom and sides and then add a bit at a
> time and see what i liked the best.
> alternately you could line the box with
> acoustic foam
> i too plan on building a bass cab in the
> near future and will be building a sealed
> single 18 to go biamped with my 4x10
> in my case i am just matching dimensions to
> my 4 x10 and adjusting depth to make the
> correct volume. though i don't plan on
> purple shag either :-p .but the endless
> options with diy are what make it so much
> fun

Yeah, I realize that I'll have to experiment with the stuffing, in the end, but my predicament is in calculating the enclosure volume. As I originally stated, I am aware that stuffing a cabinet makes the drivers behave as if they are in a bigger cabinet. When I calculate the size of the cabinet, it puts me at 6 to 6.5 cubic feet (unstuffed). So, depending how much stuffing I use, I will need to make the cabinets smaller to avoid screwing up the total cabinet Q and the low freq response. So, the problem here is ... how MUCH smaller to make the cabinets to allow for the added apparent volume the stuffing creates as seen by the drivers. As I also originally mentioned, one guy said that stuffing makes the drivers "see" the cabinet as 20% larger. But I don't know if he was refering to light, medium, or heavy stuffing. If I don't have a pretty close idea as to the effect the stuffing will have on the drivers, then I run a great risk of building cabinets that will be too small or too large, which will definately screw up the low freq response and cabinet Q, rendering the cabinets useless. If you look into the effect of how cabinet size effects the low freq response and the Q in a sealed cabinet, you will find that there is not all that much room for variance. I REALLY need someone to respond who has definitive knowledge as to the perceived volume that stuffing creates. I also need someone to respond to my cabinet shape dilemma. I just want to confirm whether one shape will indeed be better than the other regarding defraction.

Best of luck with your project. Keep on thumpin.

[groovatism]

> You need to get a hold of Dave Tenney. He is
> a bass head. Stand up bass, electric etc. He
> built a bass cabinent called Tuba 24. I dont
> think he has it on his web site.

> <A HREF="http://www.wadsnet.com/~dtenney/">http://www.wadsnet.com/~dtenney/</A>

Thanks. Yeah, he's definately a bass kinda guy, and has done quite a bit of DIY speaker work. It's too bad the bass cabinet isn't on his site ... with a name like Tuba24, it MUST be something unique and interesting. I think I'll drop him an email and ask him to have a look at this thread.

Cheers

[mloretitsch]

I will answer inline...

> I'm in the preliminary planning stage for 2
> bass guitar cabinets. Each will have a
> 15" speaker (which I've already
> purchased) in a sealed cabinet. Running the
> numbers, the cabinet will need to be 6 to
> 6.5 cubic feet (unstuffed), which is a bit
> large, but fine.

Not it's not fine. What driver are you using? 6 cubic feet and a 15" will most likely exceed xmax with a few hundred watts of power destroying the driver in short order. 3 questions, what drivers do you have? How much amplifier power is available? How loud do you play it?

> They will be made of 1" plywood, using
> ripped 2x4s to cleat all of the inside
> edges, to middle-brace each panel, and to
> provide front-to-back, top-to-bottom, and
> side-to-side bracing. They will be
> "glued & screwed", for
> transporting stability.

Stroger construction methods exist. This will certainly work and will be heavy. Standard pro construction would be all 13 ply baltic birch. It comes in 5'x5' sheets ONLY. Only available from real lumber stores. 1.5" double thickness front baffle. .75" single thickness sides and back. All bracing and panels 1/4" dadoed into eachother, glued, and stapled or screwed. This is far stronger than **** joints and screws. This style would be lighter and stronger provided you have the abilities.

> For the baffles, I will do the regular
> speaker cutout, but then I'm going to
> laminate a piece of 1/4" plywood to it,
> cutting a circle in it, slightly larger than
> the diameter of the speaker (more on this -
> read on), before I put them together. This
> will strengthen the baffle, plus provide
> flush-mounting without routing. Once the
> speaker is installed, I'll stretch black
> speaker cloth over the speaker, and attach
> it by using piping between the edge of the
> speaker and the 1/4" plywood cutout,
> using small brass screws to help secure the
> piping. This will provide physical
> protection of the speaker, retaining the
> flush-mount status. This will be necessary
> because, unlike typical instrument cabinets,
> there will be no overhang of the sides, top,
> and bottom, past the baffle, nor past the
> rear panel.

Okay. In lieu of a router it will work acceptably. I'm leary of not extending past the baffle on the front of the cabinet. You're asking for damage unless you are extremely careful and keep all the punters away from your gear.

> All edges will be radiused 1/2", and
> the cabinets will be covered in snakeskin
> naugahyde.

Not my aesthetic choice, but will work. Rounded corners really help prevent damage to the wood and finish. I opt for pro paint such as sherwin williams polane 700t. Same stuff EAW uses among others. Tough as hell. Difficult to apply.

> All hardware will be black. They'll have
> metal corner protectors, metal cup-style
> side handles (like on a Marshall cabinet),
> large rubber feet, and pop-in/pop-out
> casters.

Cool. I like the all steel penn handles.
<A HREF="http://www.partsexpress.com/pe/showd...number=260-705">http://www.partsexpress.com/pe/showd...number=260-705</A>

> The only electrical connection will be a
> 1/4", gold-plated jack, which will be
> in the middle at the top of the back of the
> cabinet. The jack will reside in a 4" x
> 4" wooden box inside the cabinet, so
> that there will be no air leakage through
> the jack (I'll caulk-seal it, where the
> speaker cable enters the little box).

Will work okay. Neutrik connectors are usually airtight...note the USUALLY part. I like speakons, but most bass heads are 1/4" out that I see.

> ALL THAT BEING SAID...I still have two
> problems:

> The First Problem: The shape of the
> cabinets. I have two completely different
> dimension options, both of which I've been
> given expert advice to use.

> The first option is to use the golden ratio:
> .6 x 1 x 1.6, mounting the speaker centered
> horizontally (the "1" dimension),
> and about an inch from the top vertically
> (the "1.6" dimension). This design
> is to theoretically minimize standing waves
> and turbulence problems within the cabinets.
> However, an expert told me that those
> benefits, in a sealed cabinet, are
> out-weighed by diffractional problems
> outside the cabinet using this design
> methodology, even when employing a
> flush-mounted speaker on a baffle with
> radiused edges.

> The second option (which that same expert
> suggests I use) is to make the cabinets
> 18"H x 18"W, and then as deep as I
> need them to provide the proper cabinet
> volume.

Box dimensions should be suited to fitting through doorways and inside of your transport vehicle. It sucks not being able to get through a doorway believe me! I've had em' as narrow as 24 inches at load in. Golden ration is out there yes, but will likely be inaudible in your cabinet compared to proper box sizing.

> The Second Problem: Stuffing. I did a lot of
> Google-searching regarding stuffing, yet
> found nothing to specifically help me in
> this particular situation. Here are some of
> the things I found, but as we all know, most
> information on the internet is
> misinformation, or peoples' unsupported
> opinions...

> * "Stuffing a cabinet makes the
> speakers think they are in a box which is
> approximately 20% larger." However,
> this person did not specify if this 20%
> figure is in a heavily-stuffed cabinet, or
> lightly stuffed. He also did not say if this
> holds true in EVERY cabinet type; sealed,
> vented, ported, isobaric, et cetera. He also
> did not specify which TYPE of stuffing
> yields this result. It stands to reason that
> different amounts, types, and densities of
> stuffing will have very different effects on
> the speakers' perception regarding the
> volume of the cabinet. Correct knowledge of
> this phenomenon is imperative before
> starting design of the cabinet, as it will
> drastically alter the required size of the
> cabinet.

> * Regarding stuffing guitar and bass guitar
> cabinets, I read SO many conflicting
> opinions and results. Some say that stuffing
> deadens the sound undesireably, and makes
> the midrange dull and lifeless. Others say
> their cabinet sounded awful until they
> "packed it tightly" with stuffing.
> Some bass guitar cabinet manufacturers use
> no stuffing, some use a layer of stuffing
> attached to all insides surfaces, some use a
> layer of stuffing on half of the inside
> surfaces, and then some stuff them
> completely.

> * One site gave (IMO) the best description
> of properly stuffing a cabinet. My
> understanding of his method is that you must
> calculate the cabinet size to be close to
> what it must be with it's stuffing, then
> adjust (fine-tune) the exact amount of
> stuffing (once the cabinet is assembled)
> according to frequency response, impedence
> effect on the speaker, and (of course) your
> ears. However, as all other experts, he did
> not go into the most important aspects of
> how to carry-out his methodology:

> * How do you know, with reasonable accuracy,
> approximately how much stuffing will finally
> be used? How do you calculate where your
> "starting point" with the stuffing
> will be, with which to "fine tune"
> from? This knowledge is imperative, as I
> said before, as the properly calculated
> amount of stuffing to be used greatly
> impacts the cabinet size.

> * He stated that "fine-tuning" the
> stuffing is accomplished using the factors
> of frequency response, impedence, and your
> ears. My foresight tells me that these three
> factors will somewhat conflict. Logic
> dictates that this will be a give-and-take
> situation, and that this will be a balancing
> act, but it DOES make sense. My take on this
> procedure is that, in the end, the ears will
> be the final judge. If it sounds right, the
> other two factors are probably going to
> naturally fall into line. I may be totally
> wrong, but that reasoning makes sense to me.

yes it is a balancing act. If it were just a subwoofer the stuffing doesn't do jack for anything pro audio. Being that you are playing the 15" much higher yes damping is good. Lining the walls with acoustic foam will dampen the box. Adding stuffing will make the box appear larger. To see a 20% increase in box size you would need to fully fill the entire box with several pounds of stuffing. This may cause your woofer to overheat in a professional situation. I would not undersize the box and rely on stuffing. Actually I would just line the box with acoustic foam and not stuff at all in favor of longevity. Any weirdness can be made up with EQ.

> I apologize that this post is rather long,
> but I know that if I give as much
> information as possible, I stand the chance
> of getting the best help. Expert help is
> desperately needed at this point, and I will
> be very grateful for it. In particular,
> information regarding stuffing, in regards
> to the primary stages of speaker cabinet
> design, is virtually non-existent. With
> expert participation in this thread, it may
> indeed become a great resource for others in
> the same position, which I assume is a LOT
> of people.

> Thanks, in advance, for your help and
> participation.

> Sincerely,
> A "Baffled" Builder

I use the Tuba 24s loaded with hl-10a's. They are a fine box indeed and half inch ply. I also use tuba 36's made out of half inch. 1500 watts rms to each and will play reliably for 8 hours (as long as I've cranked them). My other subs are 18's loaded in 7 cu ft boxes driven at 1500 watts rms each as well. These are traditional construction baltic birch cabinets and are heavy.

I recognize the sound you are after and it is pleasent to hear. I typically cut 2-4db at 200hz and boost 2db at 60hz to get a cleaner more articulate sound from a bass player. If they slap quite a bit I might work the high eq as well on that channel.

What experts have you talked to? Other bass players? Speaker builders? Pro audio speaker builders? This definetly flies in the face of convention and may sound good...but you are running the risk of damage from what I see.

If you give me the woofer model and available power we can determine if you will be okay or not.

-Matt

[groovatism]

> I will answer inline...

> Not it's not fine. What driver are you
> using? 6 cubic feet and a 15" will most
> likely exceed xmax with a few hundred watts
> of power destroying the driver in short
> order. 3 questions, what drivers do you
> have? How much amplifier power is available?
> How loud do you play it?

> Stroger construction methods exist. This
> will certainly work and will be heavy.
> Standard pro construction would be all 13
> ply baltic birch. It comes in 5'x5' sheets
> ONLY. Only available from real lumber
> stores. 1.5" double thickness front
> baffle. .75" single thickness sides and
> back. All bracing and panels 1/4"
> dadoed into eachother, glued, and stapled or
> screwed. This is far stronger than ****
> joints and screws. This style would be
> lighter and stronger provided you have the
> abilities.

> Okay. In lieu of a router it will work
> acceptably. I'm leary of not extending past
> the baffle on the front of the cabinet.
> You're asking for damage unless you are
> extremely careful and keep all the punters
> away from your gear.

> Not my aesthetic choice, but will work.
> Rounded corners really help prevent damage
> to the wood and finish. I opt for pro paint
> such as sherwin williams polane 700t. Same
> stuff EAW uses among others. Tough as hell.
> Difficult to apply.

> Cool. I like the all steel penn handles.
>
> <A HREF="http://www.partsexpress.com/pe/showd...number=260-705">http://www.partsexpress.com/pe/showd...number=260-705</A>
> Will work okay. Neutrik connectors are
> usually airtight...note the USUALLY part. I
> like speakons, but most bass heads are
> 1/4" out that I see.

> Box dimensions should be suited to fitting
> through doorways and inside of your
> transport vehicle. It sucks not being able
> to get through a doorway believe me! I've
> had em' as narrow as 24 inches at load in.
> Golden ration is out there yes, but will
> likely be inaudible in your cabinet compared
> to proper box sizing.

> yes it is a balancing act. If it were just a
> subwoofer the stuffing doesn't do jack for
> anything pro audio. Being that you are
> playing the 15" much higher yes damping
> is good. Lining the walls with acoustic foam
> will dampen the box. Adding stuffing will
> make the box appear larger. To see a 20%
> increase in box size you would need to fully
> fill the entire box with several pounds of
> stuffing. This may cause your woofer to
> overheat in a professional situation. I
> would not undersize the box and rely on
> stuffing. Actually I would just line the box
> with acoustic foam and not stuff at all in
> favor of longevity. Any weirdness can be
> made up with EQ.

> I use the Tuba 24s loaded with hl-10a's.
> They are a fine box indeed and half inch
> ply. I also use tuba 36's made out of half
> inch. 1500 watts rms to each and will play
> reliably for 8 hours (as long as I've
> cranked them). My other subs are 18's loaded
> in 7 cu ft boxes driven at 1500 watts rms
> each as well. These are traditional
> construction baltic birch cabinets and are
> heavy.

> I recognize the sound you are after and it
> is pleasent to hear. I typically cut 2-4db
> at 200hz and boost 2db at 60hz to get a
> cleaner more articulate sound from a bass
> player. If they slap quite a bit I might
> work the high eq as well on that channel.

> What experts have you talked to? Other bass
> players? Speaker builders? Pro audio speaker
> builders? This definetly flies in the face
> of convention and may sound good...but you
> are running the risk of damage from what I
> see.

> If you give me the woofer model and
> available power we can determine if you will
> be okay or not.

> -Matt

Matt, you rock, Brother! Here's the speaker specs:

paper cone/accordion surround, 50 oz magnet, 2.5" kapton vc, 250 watts rms/500 peak, 35-4k freq range, 100db spl, 8 ohms/6.4 RE.

FS 36hz
VAS 8.29 cu ft
QTS 8.26
QES .888
QMS 11.83
BL 12.76
Le 468.73 uH
Mms 98.98
Xmax .25"
Xmech .5"

I'm not into "loud", especially, just clean, clear, and heard. Loud enough to keep up with a drum kit is about it. I'll be running the two 1x15 cabs with my Ashdown MAG300, which is "307 walls rms" lol. I very much doubt the volume knob will ever go past five. It has two 1/4" speaker outputs (no Speakons), hence the 1/4" connectors on the cabinets.

You are absolutelty correct regarding construction method. Indeed I could use the expensive plywood, but IMO it's overrated (for the price ... ouch). I'm using the 1" ply (one side clear) because I've always used it, with great results, no problems, and it's relatively inexpensive (as wood goes these days ... ughh). I'll be using finger joints, not **** joints, but given that it will be "glued and screwed", and will have very good bracing, it will travel like a tank. Also, as I'm sure you are aware, almost every "pro-sound" cabinet uses a 3/4" baffle, like the rest of the cabinet. I'm sure my 1 1/4" baffle will be more than adequate. I chose the unusual construction method for the baffle because it serves three purposes ... it thickens and strengthens the baffle a bit, eliminates the pain-in-the-*** circular routing for the speaker inset, and allows me to attach the speaker cloth over only the speaker. It will give it a unique look. As far as the snakeskin naugahyde, I just feel it will give it a sort-of Texas blues "cool factor".

Lastly, and DEFINATELY not least,I REALLY appreciate your clarification on the stuffing. I'll go with 26" x 24" x 24", line the inside walls with acoustic foam, and pray for the best results. That is what I figured I'd end-up doing, and your help confirmed it for me.

[madrok]

Large guitar and bass amps are dipole. They run the driver in a baffle, with a little stuffing and a brace behind it. That makes the cabinet MUCH lighter. The sound is very dependent on room placement.

The other night I had our bass player try out the sealed PA system I have, which is vented, 4ft3, tuned to 50Hz. We were astonished by the extra deep bass it gave, and the all-round better mellower tone, in comparison to his 4x12s.

We were also disappointed by its comparative lack of dynamics, especially when plucked and slammed. I'm sure it would have had trouble, driven with its 150watt amp. The open baffle bass amp with. like, 20 watts was much louder.

So, use a high efficiency bass guitar speaker in a dipole box.

[groovatism]

> Large guitar and bass amps are dipole. They
> run the driver in a baffle, with a little
> stuffing and a brace behind it. That makes
> the cabinet MUCH lighter. The sound is very
> dependent on room placement.

> The other night I had our bass player try
> out the sealed PA system I have, which is
> vented, 4ft3, tuned to 50Hz. We were
> astonished by the extra deep bass it gave,
> and the all-round better mellower tone, in
> comparison to his 4x12s.

> We were also disappointed by its comparative
> lack of dynamics, especially when plucked
> and slammed. I'm sure it would have had
> trouble, driven with its 150watt amp. The
> open baffle bass amp with. like, 20 watts
> was much louder.

> So, use a high efficiency bass guitar
> speaker in a dipole box.

By "dipole", I assume you are referring to a ported or vented cabinet design. I've already covered that, considerably, in this thread. I have full understanding of the pros and cons of various types of cabinet construction, but have chosen this route for very good reason (TONE!).

If your bass player is playing through a sealed 4x12 cabinet, I assume that it is probably a guitar cabinet, not a cabinet intended for bass guitar, as I am unaware of any sealed 4x12 bass cabinets currently on the market (perhaps I missed one?), and only a couple that were manufactured at all. If indeed he is using a guitar cabinet, figuring that it should be "big enough" for bass guitar, then of course it sounds terrible. A good sealed cabinet, specifically designed for bass guitar, is capable of giving some of the most clear, articulate, full sound imaginable. If you do a bit of searching, you will find that sealed cabinets for bass guitar are very common, especially in the high-end market. One of the most popular bass cabinets of all time, the 8x10 Ampeg SVT, is a sealed cabinet.

[mloretitsch]

Hey Groovatism....

Did some poking around with that speaker. It will probably hold up okay in a 6.0 cu ft. box. It has a rising response between 50 and 150hz. Power handling may be a little bit limited below 50hz, but will probably be okay if you don't clip your amp into it. F3 of 41hz roundabout which will catch your low E.

The slight rise around 100-150 may make it sound a little bit boomy, or may be just the tone you're looking for.

I also checked it in a 4 cu ft. box. The response is a little peakier and the F3 moves up to 46hz.

I'll email you the max power graph. Where the power handling dips, the impedance generally is high so you won't be dumping that much power into the driver anyhow.

-Matt

[madrok]

OK. It may have been a big guitar cabinet. Still, when I say dipole, I should say open back. And most guitar amps are that.

The bass maps I have seen may be ported, but all they really have is a bunch of holes in the back of the cabinet, which I think double as vents for the (presumably) tube amp.

The little practice ones are sealed.

[groovatism]

> Hey Groovatism....

> Did some poking around with that speaker. It
> will probably hold up okay in a 6.0 cu ft.
> box. It has a rising response between 50 and
> 150hz. Power handling may be a little bit
> limited below 50hz, but will probably be
> okay if you don't clip your amp into it. F3
> of 41hz roundabout which will catch your low
> E.

> The slight rise around 100-150 may make it
> sound a little bit boomy, or may be just the
> tone you're looking for.

> I also checked it in a 4 cu ft. box. The
> response is a little peakier and the F3
> moves up to 46hz.

> I'll email you the max power graph. Where
> the power handling dips, the impedance
> generally is high so you won't be dumping
> that much power into the driver anyhow.

> -Matt

Hehehe you're right on the money. Yeah, I did all my calculations before-hand, and double-checked myself. When I was crunching the calcs, with the 6.5 cu' cab, the freg response fell nicely into place (I believe it was 40.1) with a QTC of just shy of 1.3, which is where that beautiful "smooth punch" comes from in high-end, sealed boutique bass guitar cabinets. That "slight rise" which you mentioned (which is an elevated QTC from what would be "normal" in a typical home audio or public address cabinet) is part of what gives this type of bass guitar cabinet it's "magical" sound.

Thanks again for all the help. I really appreciate your thorough attention to detail, and your follow-up.

[davet]

First off...What driver are you using?

Pro sound stuff is way different than hifi stuff, as others have pointed out. You are not trying to create a box with the same type of alignment as you would a home speaker cabinet. In pro sound you have to consider power handling, cabinet weight and portability in the equation.

As far as construction is concerned, I tend to use either 1/2" or 3/4" with some bracing.

If you really want a killer bass guitar setup, go here: <A HREF="http://www.billfitzmaurice.com/">http://www.billfitzmaurice.com/</A>

Build a Tuba 24 for a sub and a DR250 for a top. That setup will slay a 2x15 in a ported or sealed cabinet. In fact it will probably sound better than any cabinet you could buy.

Return the 2 15's that you bought.

If you're really stuck on using the 15's, I'll try to help you come up with a cabinet (or better yet, two cabinets) that will work.

For bass, I use 2 1x12 cabs that I built loaded with Eminence Delta 12LF's and tweeters. I also own an Ampeg 4x10, an SWR redhead, an Ampeg 1x15, and a Peavey 1x15. My 1x12 cabs are smaller and put out more low end than any of the above cabinets.

I have a pair of the Tuba 24’s I mentioned above, but use them for subs in a PA.

That's my advice, and I’m stickin’ to it!

Dave

> I'm in the preliminary planning stage for 2
> bass guitar cabinets. Each will have a
> 15" speaker (which I've already
> purchased) in a sealed cabinet. Running the
> numbers, the cabinet will need to be 6 to
> 6.5 cubic feet (unstuffed), which is a bit
> large, but fine.

> They will be made of 1" plywood, using
> ripped 2x4s to cleat all of the inside
> edges, to middle-brace each panel, and to
> provide front-to-back, top-to-bottom, and
> side-to-side bracing. They will be
> "glued & screwed", for
> transporting stability.

> For the baffles, I will do the regular
> speaker cutout, but then I'm going to
> laminate a piece of 1/4" plywood to it,
> cutting a circle in it, slightly larger than
> the diameter of the speaker (more on this -
> read on), before I put them together. This
> will strengthen the baffle, plus provide
> flush-mounting without routing. Once the
> speaker is installed, I'll stretch black
> speaker cloth over the speaker, and attach
> it by using piping between the edge of the
> speaker and the 1/4" plywood cutout,
> using small brass screws to help secure the
> piping. This will provide physical
> protection of the speaker, retaining the
> flush-mount status. This will be necessary
> because, unlike typical instrument cabinets,
> there will be no overhang of the sides, top,
> and bottom, past the baffle, nor past the
> rear panel.

> All edges will be radiused 1/2", and
> the cabinets will be covered in snakeskin
> naugahyde.

> All hardware will be black. They'll have
> metal corner protectors, metal cup-style
> side handles (like on a Marshall cabinet),
> large rubber feet, and pop-in/pop-out
> casters.

> The only electrical connection will be a
> 1/4", gold-plated jack, which will be
> in the middle at the top of the back of the
> cabinet. The jack will reside in a 4" x
> 4" wooden box inside the cabinet, so
> that there will be no air leakage through
> the jack (I'll caulk-seal it, where the
> speaker cable enters the little box).

> ALL THAT BEING SAID...I still have two
> problems:

> The First Problem: The shape of the
> cabinets. I have two completely different
> dimension options, both of which I've been
> given expert advice to use.

> The first option is to use the golden ratio:
> .6 x 1 x 1.6, mounting the speaker centered
> horizontally (the "1" dimension),
> and about an inch from the top vertically
> (the "1.6" dimension). This design
> is to theoretically minimize standing waves
> and turbulence problems within the cabinets.
> However, an expert told me that those
> benefits, in a sealed cabinet, are
> out-weighed by diffractional problems
> outside the cabinet using this design
> methodology, even when employing a
> flush-mounted speaker on a baffle with
> radiused edges.

> The second option (which that same expert
> suggests I use) is to make the cabinets
> 18"H x 18"W, and then as deep as I
> need them to provide the proper cabinet
> volume.

> The Second Problem: Stuffing. I did a lot of
> Google-searching regarding stuffing, yet
> found nothing to specifically help me in
> this particular situation. Here are some of
> the things I found, but as we all know, most
> information on the internet is
> misinformation, or peoples' unsupported
> opinions...

> * "Stuffing a cabinet makes the
> speakers think they are in a box which is
> approximately 20% larger." However,
> this person did not specify if this 20%
> figure is in a heavily-stuffed cabinet, or
> lightly stuffed. He also did not say if this
> holds true in EVERY cabinet type; sealed,
> vented, ported, isobaric, et cetera. He also
> did not specify which TYPE of stuffing
> yields this result. It stands to reason that
> different amounts, types, and densities of
> stuffing will have very different effects on
> the speakers' perception regarding the
> volume of the cabinet. Correct knowledge of
> this phenomenon is imperative before
> starting design of the cabinet, as it will
> drastically alter the required size of the
> cabinet.

> * Regarding stuffing guitar and bass guitar
> cabinets, I read SO many conflicting
> opinions and results. Some say that stuffing
> deadens the sound undesireably, and makes
> the midrange dull and lifeless. Others say
> their cabinet sounded awful until they
> "packed it tightly" with stuffing.
> Some bass guitar cabinet manufacturers use
> no stuffing, some use a layer of stuffing
> attached to all insides surfaces, some use a
> layer of stuffing on half of the inside
> surfaces, and then some stuff them
> completely.

> * One site gave (IMO) the best description
> of properly stuffing a cabinet. My
> understanding of his method is that you must
> calculate the cabinet size to be close to
> what it must be with it's stuffing, then
> adjust (fine-tune) the exact amount of
> stuffing (once the cabinet is assembled)
> according to frequency response, impedence
> effect on the speaker, and (of course) your
> ears. However, as all other experts, he did
> not go into the most important aspects of
> how to carry-out his methodology:

> * How do you know, with reasonable accuracy,
> approximately how much stuffing will finally
> be used? How do you calculate where your
> "starting point" with the stuffing
> will be, with which to "fine tune"
> from? This knowledge is imperative, as I
> said before, as the properly calculated
> amount of stuffing to be used greatly
> impacts the cabinet size.

> * He stated that "fine-tuning" the
> stuffing is accomplished using the factors
> of frequency response, impedence, and your
> ears. My foresight tells me that these three
> factors will somewhat conflict. Logic
> dictates that this will be a give-and-take
> situation, and that this will be a balancing
> act, but it DOES make sense. My take on this
> procedure is that, in the end, the ears will
> be the final judge. If it sounds right, the
> other two factors are probably going to
> naturally fall into line. I may be totally
> wrong, but that reasoning makes sense to me.

> I apologize that this post is rather long,
> but I know that if I give as much
> information as possible, I stand the chance
> of getting the best help. Expert help is
> desperately needed at this point, and I will
> be very grateful for it. In particular,
> information regarding stuffing, in regards
> to the primary stages of speaker cabinet
> design, is virtually non-existent. With
> expert participation in this thread, it may
> indeed become a great resource for others in
> the same position, which I assume is a LOT
> of people.

> Thanks, in advance, for your help and
> participation.

> Sincerely,
> A "Baffled" Builder

[groovatism]

> OK. It may have been a big guitar cabinet.
> Still, when I say dipole, I should say open
> back. And most guitar amps are that.

> The bass maps I have seen may be ported, but
> all they really have is a bunch of holes in
> the back of the cabinet, which I think
> double as vents for the (presumably) tube
> amp.

> The little practice ones are sealed.

Actually, typical little practice bass amps are ported, in order to get more bass end out the little 8 or 10 inch speaker. Also, it is VERY unusual to see a bass amp with a port anywhere but on the front of the baffle. Usually, bass guitar cabinets have either one or two round ports, or a vent running along the bottom or one side of the cabinet. I don't recall ever seeing a manufactured bass guitar amp which is open-backed. If you'd ever played bass through an open-backed guitar amp, you would understand why.

[groovatism]

> First off...What driver are you using?

The specs are listed in this thread.

> Pro sound stuff is way different than hifi
> stuff, as others have pointed out. You are
> not trying to create a box with the same
> type of alignment as you would a home
> speaker cabinet. In pro sound you have to
> consider power handling, cabinet weight and
> portability in the equation.

Those factors have all been considered and addressed in this thread.

> As far as construction is concerned, I tend
> to use either 1/2" or 3/4" with
> some bracing.

So do most manufacturers ... that's why I'm building my own

> If you really want a killer bass guitar
> setup, go here:
> <A HREF="http://www.billfitzmaurice.com/">http://www.billfitzmaurice.com/</A> Build a
> Tuba 24 for a sub and a DR250 for a top.
> That setup will slay a 2x15 in a ported or
> sealed cabinet. In fact it will probably
> sound better than any cabinet you could buy.

IMO folded horns sound like crap for bass guitar, and I'm not looking to "slay" anything. I will have AWESOME SOUND.

> Return the 2 15's that you bought.

Not in this lifetime.

> If you're really stuck on using the 15's,
> I'll try to help you come up with a cabinet
> (or better yet, two cabinets) that will
> work.

LOL these cabinets will work, like a CHARM.

> For bass, I use 2 1x12 cabs that I built
> loaded with Eminence Delta 12LF's and
> tweeters. I also own an Ampeg 4x10, an SWR
> redhead, an Ampeg 1x15, and a Peavey 1x15.
> My 1x12 cabs are smaller and put out more
> low end than any of the above cabinets.

> I have a pair of the Tuba 24’s I mentioned
> above, but use them for subs in a PA.

> That's my advice, and I’m stickin’ to it!

Kewl ... thanks.

> Dave

[davet]

Sorry I couldn't help you.

Dave