Separate subs or big 3-way cabs?

[blinz]

I used to have a huge PA that I sold off about 12 years ago and I'm looking to get back into running sound for some local bands - small to mid size clubs mainly. My old system was too big. It was 3 way but every piece was a separate cab - 2x18" cabs for subs, then 2x12 for mids, then big horns on top. I want something fairly compact that will do the job and sound good. I'm looking at 2 options for the mains right now:

 

1- A pair of used Carvin 1588 cabs - huge 3 way w/ 2x15, 2x8, and horn. They handle tons of power and would probably do the job with just that pair. i can get the pair for $400.

 

2- A pair of used EV SH-1512 mid/high cabs (15 + horn) and then a used 2x18 sub cab. I can get the EVs for $200 and the 2x18 sub for $200.

 

So, the price is the same either way. Which way would be better to go and why?

[GCDEF]

Subs will give you better bass almost every time. I'd think you'd get tired of hauling those 1588s too. They're very big and heavy.

[Square]

If you were in the game 12 years ago and are now thinking about gtting back in, then like me you are not terribly young (I am 37). I would go with multiple smaller boxes as you will find them easier to single hand at the gig and around the shop.

 

I am also a fan of the EV 1502/1512. They are a little low mid heavy but are decent cabinets. I used to have 8 of the 1502's spread across 4 rigs. Now I use the EV QRx series (which has a nice 2X18 that only weighs 150lbs).

[blinz]

 

Subs will give you better bass almost every time. I'd think you'd get tired of hauling those 1588s too. They're very big and heavy.

 

 

You're probably right about the separate sub. The 2x18 I'm looking at is about the same size as the 1588 though so that is not too big a deal. Nothing a handtruck can't fix.

[Craig Vecchione]

The EV. It's a bit more flexible...as they're smaller and you can use just the 15's for smaller gigs and leave the sub home. They are very efficient, so don't let the low power handling fool you. But mostly I recommend them because they sound pretty damned good.

 

I will say that I'd look for a pair of 1x18 subs instead of the 2x18. There's a huge difference in portability, if not total size.

[blinz]

 

If you were in the game 12 years ago and are now thinking about gtting back in, then like me you are not terribly young (I am 37). I would go with multiple smaller boxes as you will find them easier to single hand at the gig and around the shop. I am also a fan of the EV 1502/1512. They are a little low mid heavy but are decent cabinets. I used to have 8 of the 1502's spread across 4 rigs. Now I use the EV QRx series (which has a nice 2X18 that only weighs 150lbs).

 

 

You've got me by a couple years, but yeah, I'm not in my 20's anymore. I'm 33. I hired out to run sound for a number of local cover bands over the course of about 3 or 4 years when I was in college whenever my band wasn't playing. It was a way to make some extra money with my gear.

[blinz]

One other idea as a possiblity. A guy about an hour from me is trying to unload some cabs that were built by a carpenter from a JBL design. They are completely unloaded but he only wants like $10 per cab for them. The subs are horn loaded 1x15 or 1x18 (don't remember) and the mid/highs are 2x12 and horn. I have seen detailed pictures and they do appear well made.

[GCDEF]

 

You're probably right about the separate sub. The 2x18 I'm looking at is about the same size as the 1588 though so that is not too big a deal. Nothing a handtruck can't fix.

 

 

You've still got to get it in and out of the van, and up on the stage though.

[blinz]

 

You've still got to get it in and out of the van, and up on the stage though.

 

 

True

[agedhorse]

 

One other idea as a possiblity. A guy about an hour from me is trying to unload some cabs that were built by a carpenter from a JBL design. They are completely unloaded but he only wants like $10 per cab for them. The subs are horn loaded 1x15 or 1x18 (don't remember) and the mid/highs are 2x12 and horn. I have seen detailed pictures and they do appear well made.

 

 

Don't waste your time or money. Old, big and heavy. By the time you get done loading them with speakers (and the HF horn which will be pretty expensive to fit the cut out, JBL 2300 series?) There's a lot of compact modern stuff that would not cost much more and be about 1/2 the size/weight for the same performance.

[aw_dee_o]

You can't achieve high spl's, low distortion and wide bandwidth without having at least "reasonable" cabinet size and driver displacement. It's called physics. Anybody that tells you differently is either lying to you, doesn't know what they are talking about or is forgetting to mention the trade-off's that go with a specific smaller design. Going to smaller cabinet designs will almost certainly compromise system bandwidth ( deep bass ) and max spl capacity.

 

Having said that, "BIG" cabinets should be reserved strictly for low frequency use. Driver size, baffle area, box volume and driver / cabinet alignment are what contribute most to what dictates performance criteria here. One could use two smaller ( but NOT "small" ) 1 x 15" or 1 x 18" cabinets per side rather than one 2 x 15" or 2 x 18" if weight per cabinet and portability is important. Try to keep these crossed over below 400 Hz for best results. The lower that you can cross them, the better off you'll be. Just remember, doing so will result in your mids seeing more power and having to make longer excursions, so make sure that they are up to the task BEFORE pushing the system hard.

 

As far as mids go, you want to use smaller drivers and more of them. Having said that, efficiency and displacement is important, so don't go too small. Rather than use one larger front horn loaded 15" ( JBL 4560 style ) or two front firing 12" drivers here, go for six 8's or four 10" drivers here. Array them in a vertical line, NOT stacked side by side like a guitar cabinet. You'll end up with about the same amount of driver surface area and total cabinet height, but with much better transient response, wider dispersion, better upper midrange / lower treble clarity, wider total bandwidth, etc...

 

The wider total bandwidth and improved upper mids / lower treble is important, as it will allow you to cross the tweeter over higher. This not only improves power handling and dynamics, but will also reduce listening fatigue at higher volumes.

 

If you MUST use 12's for the mid-woofers, look at something along the lines of the Eminence Beta 12LTA's. In stock form, these offer MUCH better upper mid / treble response compared to most other 12's. In modified form, they are even better.

 

Depending on what driver / cabinet alignment you end up with for mids, these should be crossed over somewhere between 200 - 400 Hz on the low and and somewhere between 3Khz - 5 KHz on the top end.

 

If playing smaller venues with people sitting up close, you want to use front firing horns that are measurably above ear level when standing up. Two smaller horns that you can build into one cabinet and splay ( angle apart ) at an angle of at least 45* may work better than one larger horn, depending on the horns being compared. More consistent in-room response at high frequencies is what we are looking for, regardless of where one is listening. As previously mentioned, try to cross the tweeters over as high as possible i.e. at least 3 KHz if at all possible. The use of a sharp active crossover slope will work best ( 18 dB /octave or higher ), protecting both your drivers and increasing system dynamics.

 

If playing larger venues with people sitting further back, you may want to arrange the tweeters in what is called a manifold array. This would give you better projection into the distance while sacrificing some coverage up close. This requires multiple tweeters per cabinet, driving up the cost, but also lowering distortion and increasing power handling. For the best of both worlds, one can stack a manifold array of tweeters on top of the splayed tweeters, giving excellent coverage both up close and further back into the room.

 

With all of that in mind, you can build a reasonably inexpensive and very good performing PA system using well constructed utilitarian cabinets for less than what you can buy something that will cost you a LOT more and deliver a LOT less. Buying on the used market "almost" brings the new drivers / DIY cabinets into equal playing fields, but in most cases, unless you stumble upon a killer deal, DIY will still work out to be more cost effective in terms of system performance vs dollar spent. Bare in mind that using three smaller individual cabinets i.e. seperate woofers, mids, tweeters, etc.. can allow you to better aim / position each cabinet for optimum dispersion and frequency response characteristics in any given room. They are also easier to transport than one or two large cabinets per side.

 

Obviously, there are a LOT of different approaches for any given set of variables. It all boils down to what one wants, expects and is willing to do and pay for. Only you can judge which approach will make you the happiest.

 

Having said all of that, if you end up going with ANY commercial design, do some simple things that will noticeably improve the performance of the system. Replace the scrawny factory wiring inside the cabinets. Use at least 12 or 14 gauge conductors for large dynamic drivers ( 6" - 21" ) and at least 18 gauge for horns. I prefer twisted pair wiring for everything, but especially on mids and tweeters. Heavy gauge zip cord aka "Monster cable" ends up working okay for subs or woofers that are crossed over pretty low. Solder all of the connections wherever possible. Install ( staple or glue ) a layer of sound dampening material ( polyester fiberfil available from Wal-Mart works okay ) along ALL of the interior walls of the cabinets. Don't go crazy here, just a reasonably even covering. This is most important directly behind and on the sides of the drivers, as it helps to reduce reflections within the cabinet. In most cases you DO NOT want to place damping material at or very near the mouth of a port or vent, as that can drastically alter box alignment. For that matter, placing stuffing in the box that was not originally accounted for can / will alter box alignments. In most cases though, the benefits FAR outweigh the small amount of possible drawbacks.

 

If you do the above, you'll find that the commercially built speakers will typically sound FAR more dynamic with greater low end impact and definition, offer improved clarity and be noticeably smoother in overall response. You may find that the sound will change slightly ( for the better ) shortly after performing these mods / upgrades once you start throttling the system. Start off slow though, as you want to make sure that everything is working okay before cranking it way up. Performing one task at a time and sticking with it until each step is done will reduce the potential for any problems or mistakes. Sean

 

[aw_dee_o]

One more thing that i forgot to mention. Unlike the mid drivers, where you do NOT want to stack them horizontally and should stack them vertically in a straight line, it is actually preferred to do this with woofers. So long as the woofers are crossed over relatively low, it is always preferred to have multiple woofers mounted horizontally ( closer to the floor ) rather than vertically. The closer that the woofer is to the floor, the more room reinforcement that you'll get. You also want to place the cabinets as close together as possible too, as this increases coupling. Sean

 

[coyote-1]

Short of narrow spiral staircases, this really should not be a problem for anyone with brains enough to figure out the principles of leverage.

 

You've still got to get it in and out of the van, and up on the stage though.