First PA rig, advice needed

New to pro-sound/PA. In the process of building a pair of subs (Josh Ricci's SKRAM loaded with Eighteensound 21NLW9601s) and would like suggestions on tops that will keep up. Would prefer DIY but open to suggestion. The subs will probably cover 150hz or so and down. If I had the money I would opt for something like the Danley SH50 or SH46 but that will probably never happen. These will be used for small outdoor events (100 to 200 people). Would like to keep the system as simple as possible. Budget for tops around $1000 - $1500 USA. Signal chain: laptop > audio interface > 1 amp for subs and 1 amp for tops > speakers. Any suggestions or criticism appreciated.

Paul
 
For 100-200 people, I'd grab a pair of good 10" coaxials. I like the Faital Pro 10HX230, but others are available. I've dropped around 1KW of test tones (ie, far exceeding what you're supposed to do with them) and they stayed pretty linear, with only a couple of dB of compression occurring - very impressive.

I would seriously recommend purchasing a measurement microphone and learning to use it.

Chris
 
While Crown Macrotechs are decent amplifiers, I'd hesitate to recommend them in this day and age. The weight is a serious issue, especially next to something like a Powersoft T604.

If you talk to the right people, a T604 would probably cost the same as those Crown amps, and the Powersoft comes with the full suite of processing.

Times have changed...

Chris
 
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My tops cost less than $1000 USD (if you don't count your own labor) and are point source: BM-D446 on PH-4220
my tops have a 90x40 degree coverage pattern, the SH-50 has a 50x50 pattern, its worth defining a specification for your speaker covering points like the following:
1) coverage pattern (work out from expected speaker and crowd position)
2) SPL capability (from target audience SPL and speaker position)
3) bass extension (from sub crossover point)

As Chris says if you want to design speakers and set up sound systems a measurement microphone is a very good idea.

With your signal chain your only intending per-recoreded music playback? Its quite tricky to get latency low enough when using a PC for signals processing for other uses. I would recommend a dedicated DSP unit to do crossover, limiters, EQ etc. or if you haven't already purchased amplifiers you can get these functions built into the amps.
 
... its worth defining a specification for your speaker covering points like the following:
1) coverage pattern (work out from expected speaker and crowd position)
2) SPL capability (from target audience SPL and speaker position)
3) bass extension (from sub crossover point)


With your signal chain your only intending per-recoreded music playback? Its quite tricky to get latency low enough when using a PC for signals processing for other uses. I would recommend a dedicated DSP unit to do crossover, limiters, EQ etc. or if you haven't already purchased amplifiers you can get these functions built into the amps.

1) These would mostly be for large yard parties and possibly live bands at some point. The 90x40 coverage pattern you have would probably work but I wouldn't want to go any wider.
2) For SPL, I just want to get close to the SPL capabilities of the subs and have a good amount of headroom.
3) The subs are pretty flat from about 27hz to 150hz.

I was looking at miniDSP, Behringer DCX2496 among others but wanted advice on whether it would be simpler or cheaper to just get amps with built in DSP.
 
Any links to builds with those drivers? And a measuring mic and software is in the works, thanks.

The drivers are pretty new, so I'd be surprised if anyone was doing much with them yet.
I can say, however, that they start to go non-linear (including a couple of dB of compression) when you drop 1KW sine tones into them.

At sensible power levels, they're very clean.


I'd contact a dealer for a quote on a Powersoft T604. I suspect you'll be able to get one for the price of those XTIs and a DCX2496, and the Powersoft will be in a different league.

Chris
 
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Amps with DSP will lower the rack size, weight and complexity of cabling and probably simplify limiting (as you won't need to take into account amp gain). The advantage of a dedicated DSP is increased flexibility and power. For example on my DSP (Symetrix Symnet 8x8 DSP + DIGIO) I have over 40 PEQS, delays, 3 way crossover, external controls, live metering, multiple different limiters on outputs and the processing is done using floating point so I only need to worry about levels at input and output. If you get DSP amps to start with though you may find they have enough features or add a DSP later.

I wouldn't recommend the minidsp for pro use as it has a 4V maximum input voltage, some mixers are going to give you a very hot signal, I have had a +20dBu input clipping before.
 
I will definitely be on the look out for the T604. I have a friend who deals with Crown stuff so he can get me a decent discount so that is why I was leaning toward those. Any more thoughts on tops? I was reading Art's SynTripP thread and though the design is pretty complicated for my woodworking skills I may be able to pull that off. Just not sure about the final cost...thread is quite long.
 
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I will definitely be on the look out for the T604. I have a friend who deals with Crown stuff so he can get me a decent discount so that is why I was leaning toward those. Any more thoughts on tops? I was reading Art's SynTripP thread and though the design is pretty complicated for my woodworking skills I may be able to pull that off. Just not sure about the final cost...thread is quite long.

There are also the PM60/90, they will cost more than the Syntrip but look easier to build (no compound angles):
60 Degree DIY Mid Hi | Sound Forums

Building your own design around a coaxial is a good idea it simplifies construction. If you look at the SM80F you can see an example of extending the coaxial horn cone shape to given pattern control to a lower frequency:
SM80F | Danley Sound Labs, Inc.
In this design is also a 3 way which keeps the excursion of the coax to a minimum reducing modulation of the tweeter by moment of its horn. The SM80F is very heavy and large mainly due to its bass section. However with less SPL/bass extension you could make a 3 way based around a coax 10" (with possible horn front baffle) and a mid-bass 12". A high tuned (~70 Hz) bass reflex high efficiency 12" will go very loud when run with high pass filter as it will no longer be excursion limited. As high excursion is not needed the motor can be small and light while still providing a lot of motor force. Which brings me to another point in that if your stand mounting speakers its best to keep them under 25kG, mine are 31kG and lifting them onto stands on my own is a struggle. The extra expense of neo drivers is worth it in this circumstance. Some manufacturers are using popular ply which is very light and stiff but has less surface impact resistance, this can be mitigated to an extent with tough paints.