Vertical cab stacking---the only way to play

[Mika]

Looks OK, but the box volume seems very small, unless those are midrange drivers.

The cab is quite deep, and the net internal volume is ~68 liters. The drivers are B&C 8NDL51-16, so I should have 60 Hz - 5 kHz response (-3 dB) in anechoic conditions. The sensitivity is around 97 dB theoretically (91 dB for one driver at 1 W input power and 1 m measurement distance) as they're all wired in parallel.

Anyhoo, the effective diaphragm area is around the same as on an average 15", but this design has about 60 Tm of Bl.

 

[JimmyM]

Mika, I like the design a lot, but you think 60hz will be low enough response to sassify you? After all, it's not every day we get to play in anechoic conditions.

 

[Mika]

Mika, I like the design a lot, but you think 60hz will be low enough response to sassify you?

Well, the good ol' SVT 8x10" fridge doesn't have a much lower -3 dB frequency point. Being a sealed cab the fridge has less steep rolloff than my ported 4x8" and therefore is capable of reproducing some more LF. The low frequency response was one of the design tradeoffs and most likely -3 dB at 60 Hz will suit me just fine.

After all, it's not every day we get to play in anechoic conditions.

True, but it's the most common reference condition for measuring loudspeakers and hence the reference.

 

[6stringbassist]

I've read this thread over the last couple of nights, I have to say that I don't really understand a lot of what has been said, but I do know that my Accugroove Tri112 cabs sound better stacked upright than on their sides.

 

[billfitzmaurice]

Mika, I like the design a lot, but you think 60hz will be low enough response to sassify you? After all, it's not every day we get to play in anechoic conditions.

Anechoic means outdoors, indoors it will work even better. Those are superb drivers, and two of those cabs will equal a Fridge. They run about 6dB less sensitive than the drivers in an SVT, so it will take a lot more power to get there, but the response is pretty close and with the narrow footprint of a pair of those vertically stacked the dispersion will be infinitely better. The downside is that those drivers cost twice as much as something like a Basslite S2010, and will take a big amp to get the job done, but if you've got a lot of $ and a small car to lug your gear in it's a very smart option.

 

[Mika]

Anechoic means outdoors, indoors it will work even better. Those are superb drivers, and two of those cabs will equal a Fridge. They run about 6dB less sensitive than the drivers in an SVT, so it will take a lot more power to get there, but the response is pretty close and with the narrow footprint of a pair of those vertically stacked the dispersion will be infinitely better. The downside is that those drivers cost twice as much as something like a Basslite S2010, and will take a big amp to get the job done, but if you've got a lot of $ and a small car to lug your gear in it's a very smart option.

Yep, the drivers are unfortunately quite expensive. With two 4x8" cabs stacked I should have around 100 dB sensitivity, and I'd imagine that I'd be able to make quite a racket with the stack and my Genz Benz Neo-Pak 3.5 (500 W @ 2 ohms). If not, I have a spare QSC PLX3402 channel in the PA rack, so 1.7 kW @ 2 ohms is available if needed.

One of the key design criteria was that with the chosen drivers and alignment combined with a suitable highpass filter (such as the 50 Hz filter in the PLX3402), the cab will be able to take full rated thermal power without exceeding Xmax.

 

[JimmyM]

Anechoic means outdoors, indoors it will work even better. Those are superb drivers, and two of those cabs will equal a Fridge. They run about 6dB less sensitive than the drivers in an SVT, so it will take a lot more power to get there, but the response is pretty close and with the narrow footprint of a pair of those vertically stacked the dispersion will be infinitely better. The downside is that those drivers cost twice as much as something like a Basslite S2010, and will take a big amp to get the job done, but if you've got a lot of $ and a small car to lug your gear in it's a very smart option.

Anechoic means "without echo," I thought. But yeah, between you and Mika, I'm convinced. Mika, build me one and send the bill to my wife

 

[Mika]

Anechoic means "without echo," I thought. But yeah, between you and Mika, I'm convinced. Mika, build me one and send the bill to my wife

Thanks, but I'm afraid the bill would mean instant divorce at the current exchange rate and bill-of-materials.

 

[DAcat]

Vertical Array is WAYYY the best Array... Peace... DAcat

 

[pedro]

(pedro still reading and realizing he's the only shallow one.)

 

[tolson36]

I thought I'd share.

I've bought into the vertical array thing long ago. However, I've still had to deal with less than optimal stage sound for some time. Mainly inability to hear mids well enough without cranking the rig to the point other band members get drowned out. I think elevating the speaker is still a key.

The situation is a classic rock band that's fully miked or lined to a PA fully capable of all FOH. We are struggling to reduce stage sound without going to IEMs.

So while in the past---I've been asked to turn down even when I couldn't hear myself well (and sometime at all), I've finally pieced together a solution. A gig last night I was asked to turn up even when I could hear myself fairly strong. In fact, I really might have had the opposite problem--hearing myself too well and if I turned down I was getting thumbs up from everyone to turn up. A much better situation.

The pieces are a single Schroeder Mini 12 (strong mids), sitting on a 4-space rack but tilted up with a 2x4, and that sitting on an On-Stage brand amp stand. (real sturdy)

Inside the rack is a Markbass LMII. None of the pieces weigh more than 25lbs. I even put a little velcro strap on the handle of the rack to act as a guitar stand.

In the event I need more, I've got an Avatar 210 to be put in place of the stand.

Link Removed
Link Removed

 

[theshadow2001]

That second picture looks really unstable. I wouldn't fancy bring that to a bar where someone could knock into it.

 

[billfitzmaurice]

Link Removed
Link Removed

Nice, but the bare 2x and waferboard is a bit shy in the esthetics dept. On the cheap I'd paint them, matching rat fur would be sweet.

 

[tolson36]

agree, the bare wood gets finished in black spray now that I'm satisfied with the results.

On the stability thing, in both configurations it's much more stable than it looks. I've used these little bungee cords to increase stability on tilted cabs but don't think it's even necessary here.

The speaker on top is 22lbs and it really is over the center of gravity. More of the weight in most speakers is on the front side which means when tilting it back--can actually create more stability as long as the base is stable. The rack as well has more of the weight on the front side.

No doubt a drunk could knock it over (and probably could knock over even a straight vertical stack). Most places we play--we are forced to put our amps behind us and I'm not too worried.

The first stack (with the RS7000 stand) is in fact a bit more stable than the second and is the configuration I'll use 90% of the time. The back support arms on the rack extend to about 3" above the rack and so prevent the speaker from sliding off the back side. I've even place the 210 on the rack instead of the 1x12 and it still felt very stable.

I was very surprised how sturdy the RS7000 actually is. When locked down it's just as stable as any bottom cab in my opinion. If all you need a bottom cab for is stability as a platform for raising a speaker to ear level---that's a lot of weight for just that purpose.

When we are playing---if I have a cab on the bottom that adds to the low end our sound guy is already dishing out with the bins---that contributes to the mud problem and I'm back to square one. The bottom cab on a bigger stage might be needed for the rest of the band to hear me. But I'll play that by ear

btw--if you have sound guy that understands the power of the kick is centered a bit higher than 40hz--you are lucky. I haven't had any luck asking him to roll off the extreme low end. If I give him a signal with lot's of mids--he performs a smiley face on me. At times, the kick's extreme low end makes it virtually impossible to hear any of my low end.

 

[billfitzmaurice]

btw--if you have sound guy that understands the power of the kick is centered a bit higher than 40hz--you are lucky. I haven't had any luck asking him to roll off the extreme low end. If I give him a signal with lot's of mids--he performs a smiley face on me. At times, the kick's extreme low end makes it virtually impossible to hear any of my low end.

Your primary power bandwidth really should be starting in around 60 Hz, with the kick below that. Where things get messed up is when the FOH either runs the kick too high or the bass too low so that they're stepping all over each other. High end boards have sweepable HP filters on every channel, and the better FOH guys high-pass the bass around 60 to 80 Hz, to compensate for the stonger low end capability of the PA versus the backline bass cabs. The preferred method with boards that don't have that capability is to aux feed the subs, so that the only things going into the sub feed are the kick and floor toms, keys and bass, and the amount of sub content from each can be tightly controlled by the aux send of each channel strip.

 

[fdeck]

Now you need to start a poll to see how many bassplayers know who Feynman was.

 

[theshadow2001]

Your primary power bandwidth really should be starting in around 60 Hz, with the kick below that. Where things get messed up is when the FOH either runs the kick too high or the bass too low so that they're stepping all over each other. High end boards have sweepable HP filters on every channel, and the better FOH guys high-pass the bass around 60 to 80 Hz, to compensate for the stonger low end capability of the PA versus the backline bass cabs. The preferred method with boards that don't have that capability is to aux feed the subs, so that the only things going into the sub feed are the kick and floor toms, keys and bass, and the amount of sub content from each can be tightly controlled by the aux send of each channel strip.

So with aux feeding you can control how much of what goes into the subs. But how can this stop say the kick from stepping all over the bass since there's still no control on that end of the frequency spectrum on most desks (well any desk I've seen has had at most two sweepable mids and a high and low)

 

[JimmyM]

I'll tell you how you can stop it...by taking your soundman out back and teaching him a thing or two about respect and knowing his role

It's really very simple to mix a band to where it's not mud for the bassist. It's all in separating the frequencies for kick and bass. Kick gets a shot at 20-25hz and a gradual scoop down until about 2 or 3k so you get some attack (some like to go even higher...matter of taste). Bass takes over at around 60hz and takes up almost all the mids, and you might want to try a slight boost around 750-800hz to get it to power its way through clearly. Then you let the guitars fight it out for the upper frequencies and maybe give them a bit of your low end for some depth. Keys you basically run flat except maybe a rolloff on the low end. And you don't need any fancy schmancy setups to do it. They make life easier, but just knowing how frequencies work is half the battle.

But then you have to make your soundman do it. Quite honestly, if I tell a soundman how I want my bass to sound and he does the exact opposite time after time, I'd can him.

Also, this is why I think the Shure SM-58 is the best mic to use when micing bass cabs. It's got a mid hump built into it.

 

[tolson36]

"Kick gets a shot at 20-25hz"

I've always heard the power of the kick is 80. And I also thought most sound guys roll off at 50-55--so I have to question that anything is being reproduced at 20-25.

I'm not a pro though--anyone else?

 

[theshadow2001]

Now that you point it out. Yes I would agree. I don't think there are many live sound reinforcement systems that could go down that low effectively. I could be wrong though.

It could be why QSC have a 30hz cut button on their amps...I think, I'll check that one up



Yes it's a 30Hz or 50hz cut