Need some help planning a CHEAP PA setup!

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Hello.

My brother in law in Bali asked me if I could help him out with a PA setup. Amps and other electronics are expensive and hard to get down there, easiest to get locally is probably low end car stereo stuff, so thinking of bringing lower priced PA gear in my bag.

I am a bit strapped for cash, but it should be possible. Thinking of some reasonably priced 12" like for instance the Fane 12-300 combined with maybe something along the lines of Faital 3FE25, because it would be possible to get quality sound out of it, and be a bit loud.

Aiming for a roughly 75cm tall * 45cm deep * 40 cm wide box because that is what he wants, and I can get at least some bass output to 30hz with the Fane 12".

Open for other driver options.

My biggest problem is AMPS! If I go for a 2 way setup I would REALLY like to have a 4 channel amp with DSP filters, but the cash thing is a bit difficult.

If I decide what the **** and get the Fane 15-300TC and just a Behringer NX1000D it would just fit my budget, but then I do not have room for anything else at all in my bag :(

I am stuck in planning phase but need to get things done real soon, to get the parts in time. Please help!
 
Firstly, I'd suggest you won't get 30Hz out of a 12" driver at PA levels without using a very very large cabinet. Think LABhorn as a minimum.
For a direct-radiating 12", flat-to-50Hz would be a reasonable goal, and that's for a good driver.

You need to set off with the usual design questions:

- How loud?
- How low?
- How big?
- What budget?

Chris
 
It's not going to be huge SPL, the frame of reference for my brother in law is perhaps a bit schewed, since the only PA stuff he's ever heard is not very good quality.

I get 109db per box in halfspace at xmax for the Fane 12-300, ca 50 watt input. Down to 107db at 30hz. If I xo at ca 200hz there will be sort of a "party hump" from over 110db at 80 to 112db at 150hz when using a 4th order BW LP.
It's not set in stone, but this will give "good enough"sound for a decent party, and does not require expensive parts of any kind.

Budget is very limited around 1000 NOK in drivers per channel + maybe 2000 NOK in amps. So around 350£, including taxes.
 

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Why use the 3" Faital speaker at all? :confused:

Fane 12-250 TC is 10 dB more sensitive :eek: , stands 250W and reaches incredibly flat to almost 15 kHz.

Not sure why would you use a 3000W power amp to drive 2 x 250W speakers ... and that if you *forget* the puny inadequate 20W 91dB Faital that is :confused:

Also forget any mention of 30Hz.

Any reasonably portable cabinet will start dropping below 60/70 Hz and be "usable" down to 50Hz or so ... and that´s a very good response for high efficiency PA speakers.

Your in law will be very happy with 2 such cabinets, full range, and driven by a power amp with limiters set to 250W per speaker, so it never ever clips.
 
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Fane 12-250TC does not have enough low end.

My in-law specifically asked for more bass, some years ago, I made them a speaker with W5-1611 SA 5" FR in a folded voigt pipe style box, it drops like a rock after 60hz, but they like it a lot, so much that he snapped the wires from the connector to the VC because of over excursion... Even after being warned repeatedly.
So I got some new W5-1611SAF drivers here that will also accompany me on the journey.

But after I got the drivers to fix the speakers, he humbly asked if it was possible to make some speakers with more bass, quote: "Need big bass!" and also: "Want big sound, like mini concert!"

I would like something smaller with better off axis response that can keep up with the 12-300 or equivalent (See image above, or whatever else is suggested that can give more per buck invested).
The Faital 3FE25 are on my shortlist, but they would have to be ordered from another source, which again would cost more in shipping...

Passive filters would be *really* expensive to implement, since we're talking maybe 300hz xo, and I would like the freedom a DSP solution gives.

I could bring a standard minidsp 2x4 (board only), and some TPA3250 amps, but I am a bit concerned about possible reliability/end users technical ability. Maybe I could have them make a wooden box to put them in or something...

The Behringer EPQ304 is a possible candidate for power amp, it has 4 channels, it's cheap, and together with something like the Behringer CX2310 V2 filter it would work, and possibly even be repairable should the worst happen.

I've never said anything about using 3kw of power.
Just some extra info:
There is NO option to use power to get more spl, I just asked, and they have one 10A breaker fuse with 220v for the entire household, frequent brownouts and dirty power grid in general.
So one 10A fuse is for lighting, a small side of the road cafe with a refridgerator and extra lights etc, another small shop with a smaller fridge, waterpump, a tiny water heater, and a laptop + whatever else a family household with a small baby needs. I don't know, but his father just told me they have 1300w power total. So not much!

Seeing as I am severly power limited, and the last few db's to cross into 120db territory demands a certain amount of "oomph", I thought it was better to forget about it and get whatever possible down low. The restricted power is the main factor here, and since the driver I suggested can do it, why not?

Maybe I should forget the whole thing and try to squeeze 2 x Fane 15-300TC + 1 x NX1000D in my bag, all these other things take space too, maybe it's better go the basic route.
The NX1000 is not a big power monster, only 2x160W in 8 ohm, I estimate the clean power should be maybe around 2x90w or so. And the DSP would make short work out of the weak spots of the FC152.
 
Fane 12-250TC in vented box (preferably larger than 75cm * 45cm * 40 cm) and Behringer NX3000. DSP is not needed for this simple set-up, and NX3000 is more powerful and about the same price as NX1000D.

I would have gone multiple Fane 15-300TC as it has a slightly better low end. No expensive crossovers to worry about with the full range drivers.
Simple box design too, all drivers the same size.
I wouldn't put more than two in a box if you need to move them much, maybe even just one ?
 
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Allright... I think the FC152 + NX1000D might be feasible. And it would most certainly be easier than most other options.

I think it should be in a closed box, and the response looks a bit wiggly in a BR/TL type thing, but the BR/TL thingy just gives so much more output!
Closed goes 113db to 83hz, vented goes 113db to 55hz, within xmax, per channel. That is a major difference.
Vented also peaks out at 117db/80hz, while closed is at the 113db mark.

I really want to use slot ports, but they absolutely must be off the ground a bit (rats, very fat ones), so round ports a bit up are mandatory.
 
Fane 12-250TC does not have enough low end.
Fane 12-250TC has about the same low end cutoff as Fane 15-300TC in the same small box. So, 12-250TC has enough low end and is better suited to small boxes then 15-300TC.

Maybe I should forget the whole thing and try to squeeze 2 x Fane 15-300TC + 1 x NX1000D in my bag,

And the DSP would make short work out of the weak spots of the FC152.
DSP can not make better dispersion of loudspeaker at high frequencies. Forget about DSP amplifier, you need appropriate (and better) loudspeaker. But because you can not afford better loudspeaker, please accept the given advice. Ideally, 4 boxes with 12-250TC and Behringer NX3000 is all what you need - it will beat in every imaginable way the setup of 2 boxes with 15-300TC and Behringer NX1000D. Price would be about the same. Or, 2 boxes with 12-250TC will be cheaper than 2 boxes with 15-300TC.
 
I must respectfully disagree that the 15-300TC has poor dispersion, after taking care of some resonant behaviour with my DSP setup, it is better in many regards than quite a few smaller FR's I have heard.
And after reading up on the NX1000D and it's flaws, I am thinking it would be better to buy a cheap but good TPA3255 in a box with volume knob.
This will also make the 2 x 15" much more realistic, since the TPA3255 takes up so little space.

I already own the 15-300TC, I bought some of the very first of these drivers, it is impressive in so many ways.
Would you rather have a single pair of 12" than a single pair of 15"?

There is no way whatsoever that I am bringing 4 x 12" in my suitcase! It is too much!

Also, you keep suggesting the NX3000 even though I have specifically mentioned that there is a very limited amount of power available.

Even the NX1000 is pushing it! Anything with more power will not even be able to power up at all! Even with really good soft start on a big power amp the fuse might blow, since it's absolute max 10A FOR AN ENTIRE HOUSEHOLD + 1 SHOP AND A CAFE.

After some more thinking, I have decided the speakers must be sealed boxes, because of insects, lizards and rodents, it will be too tempting for geckos and rats to start living in there if the box is vented... It will be hard to make vented boxes safe enough.

So:
Fane 15-300TC
+
TPA3255 (Compact + low weight class D, good on performance, power efficiency, small size and low weight)
+
??? dsp (Perhaps this one? t.racks dsp 4x4 mini, because of price, and most importantly, it's in a box)
 
I must respectfully disagree that the 15-300TC has poor dispersion,
Every full-range has very poor dispersion at high frequencies compared to any 2-way loudspeaker with high frequency driver plus horn. DSP can not improve dispersion, period.

I already own the 15-300TC,
Well, this is the first time you mentioned that. So, when the budget is tight, then the choice is easy - use what you already have.

I have decided the speakers must be sealed boxes, because of insects, lizards and rodents, it will be too tempting for geckos and rats to start living in there if the box is vented... It will be hard to make vented boxes safe enough.
Actually, it is quite easy - metal wire mesh or perforated metal grille, covered inside with thin open-pore foam. That is the standard feature of all professional PA sound reinforcement loudspeakers.
 
As far as I know, Bali is Indonesia? In Indonesia a lot of loudspeakers we buy are manufactured. I don´t know why you want to bring Chinese stuff, bought in Europe, to a country that has very good speaker manufacturers.
Also, your idea of building an active speaker system from Wondom parts (much to expensive junk), in a place where electricity is rare and while you solder, rat´s chew your wires, seems unrealistic. Buy a Behringer NX1000D, source localy speakers, build a box with basic passive 12 dB/oct frequency x-over and trim the bass and high with the DSP oft the amp.
The amp has a soft start and draws very little energy, there is no other concept that is more efficient. If you can´t draw that little energy from the line, buy acoustic instruments and make music with your hands!
If the end user is an idiot, who ruins gear by playingt it intentionally too loud, don´t expect anything to last... small brothers are that way, some times...

Good luck

PS don´t forget the import taxes, that will be charged when you enter the country with a bag full of raw electronics,wires and heavy stuff. But, probably at the first airport you will be identified as muslim extremist with a bomb anyhow and miss your flight.
 
... I hear what you guys are saying, and maybe some places in Indonesia electronics are easily available.
But what I'seen in Bali is that the prices are higher and the selection very poor.
In a place where for instance diapers are more expensive than here in Norway, and one persons income per month is ca 230$.
They just can not afford luxury items like a stereo, things that many here take for granted.

If you go blindly about with they eyes of a tourist you may never notice this, but the people live hard lives, many work 12hour days for not much money, and they have to buy purified water for drinking. Propane for cooking costs a lot of money, heating water for showers or cleaning is a luxury that is too expensive for the locals. And it is not that hot everywhere, in Kintamani where the family lives it was mostly 12-15 degrees c and for the most part constant fog last time we where there.

The times I've gone there before, I have brought stuff like first aid equipment, since noone wil let the ambulance "sneak" in still standing traffic... :(
I have brought basic tools like saws, axes screwdrivers, because they have to travel far to find these things in a big wharehouse, and then it is a little bit more expensive than here, but horrible quality... :(
I have brought sweaters and weather resistant jackets so they do not have to be wet and cold.

This year I am bringing stuff to fix the speakers we made together years ago, and some new drivers so they can get a little bit of sound and maybe increase the income of the cafe a little bit. I am also bringing water filters so they do not have to spend so much money on bottled water.
 
First for all the non native English speaking folks, dispersion is not the dame as coverage angle when used in acoustics. Dispersion is the property that allows a prism to separate the colors of light. It refers to the fact in some media high frequencies travel faster than the lower ones. This does not occur in mono atomic gases. In real air it is affected by the humidity.

Secondly a ported box is really the way to go. Use fine wire mesh or window screen material to keep vermin out. It will require a bit bigger port area as screen is not 100% open area.

The other item might be to buy a used audio power amplifier to save a bit of money.

Also folks seem to be confused with on axis frequency response and actual energy output. With any cone driver the coverage narrows as frequency increases so with declining energy output the on axis frequency response remains flat.

As to cone over excursion it can be either operating at too low of a frequency, but more likely a resonance. A bit of fiberglass or even fabric stuffing may solve the issue.

Finally one friend rented an old beat up road case to take a brand new musical instrument through customs. He of course left with the case containing a cheap knock off.
 
Thank you Simon, I think that's the most helpful post so far.

I will have to bring some wire mesh, I can get bug mesh down there.
Ported boxes do indeed have quite a lot of advantages if done correctly.

Nothing is set in stone, or this thread would not exist, but so far it seems that a pair of either the Fane 12-250TC or the 15-300TC + a TPA3255 will give most output per amount of money in relation to weight.
Box volume is not fixed, can be increased it if nets extra output. Woodwork is cheap down there...

I am open for other suggestions and/or constructive criticism, as long as these factors are taken into account:
1. Limited total weight of components.
2. Limited physical volume of components. (In my bag with clothes etc.)
3. Limited power available on site.
4. Limited budget. (I will have to bring other hard to get items as well, I am not rich.)
 
First for all the non native English speaking folks, dispersion is not the dame as coverage angle when used in acoustics. Dispersion is the property that allows a prism to separate the colors of light.
Thanks for the clarification, "coverage angle" is the right description, I used the word "dispersion" in a rather wide meaning found in the Google dictionary:

dispersion
/dɪˈspəːʃ(ə)n/
noun
noun: dispersion
1.
the action or process of distributing things or people over a wide area.
 
The tops in my cheap PA are the fane 15 full range drivers, driven by an inuke 3000 dsp. You will need DSP on these drivers or they sound peaky in the midrange. Ive currently got 3 heafty EQ cuts at (IIRC, quite a few db at 2k, 4k and 7k). They sound OK now, but definitely not OK without the DSP.

Personally I would look at second hand stuff if budget is tight. If you want a remotely decent sounding system on the cheap its worth spending a little more and having a sub in my opinion. The fanes will deliver bass but you will have to dial in a fairly huge boost at the bottom end meaning an overall drop in level and the top end becomes a bit distorted (doppler distortion, as I found out here the other day).

If you went for a cheaper sub driver, e.g. Eminence Kappa 15LF - 15", you could probably build a decent 600 watt sub for about 200 quid. Then the lower end response of the mids / tops doesnt matter since they wont have to handle anything below 100hz or so. You also would need 2 amps (or a 4 channel amp) with DSP to effectively dial in a crossover point (sub / tops respectively).

There is a tonne of second hand PA stuff available on facebook selling pages and ebay and at good prices.

If its any help I have a pair of peavey 300 watt 15" drivers sitting about doing nothing. They could make a working sub, or use them as part of full range speakers by adding tweeters. if you cover the shipping costs I'm happy to send them over.
 
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OP specifically mentioned that there is a very limited amount of power available from the power grid and also he can't move big boxes around. Because he already have 15-300TC, one pair of vented boxes for them with some EQ boost at the box tuning frequency are the best option.
 
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