Need some help planning a CHEAP PA setup!

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I did a quick test of the t.racks DSP 4x4 mini and EPQ304. It was used as crossover and bass and high end EQ. It is not too noisy and the amplifier is quite silent, too. The only disadvantage of this combination is the fan noise. I actually think about getting a second DSP and a larger power 4ch amp to power my 4way home PA stack. And a minor disadvantage is, that the maximum crossover slope is 24 dB/oct. All in all, I think it could be a nice budget setup with the 12" Fanes (which are still in the boxes).
 
Thank you for the information pelanj. I am trying to avoid fans on the amp, still undecided on amplifier. I ordered a ready made TPA3255 that *should* be here before the airplane lifts off. It may be that it's not up to spec though, varying production quality and all that.
I do have some very nice TPA3250 left over, and a couple 3116 kits that are preserved by a thick layer of dust.
Actually considering something like the Yamaha R-N303D even if it's a bit big, because it would be a more flexible input source, and there's integrated DAB and FM tuners.

Still undecided, it's only the 12-250TC + speaker grills and OCF that are 100% go.
 
Thank you for the information pelanj. I am trying to avoid fans on the amp, still undecided on amplifier. I ordered a ready made TPA3255 that *should* be here before the airplane lifts off. It may be that it's not up to spec though, varying production quality and all that.
I do have some very nice TPA3250 left over, and a couple 3116 kits that are preserved by a thick layer of dust.
Actually considering something like the Yamaha R-N303D even if it's a bit big, because it would be a more flexible input source, and there's integrated DAB and FM tuners.

Still undecided, it's only the 12-250TC + speaker grills and OCF that are 100% go.

Re OCF: approx 65mm thick, cut cone shaped hole, inner = mid cone diameter (125mm IIRC), outer hole 25-50mm, depending on acceptable losses v HF dispersion. Lots of room to play with thickness and hole sizes. Try and make the foam overhang the edge of the driver equal or greater than the thickness of foam.

I would say that melamine acoustic foam would be the best for this.
 
Thank you, I really appreciate the information.
I was thinking of using this stuff:
https://www.biltema.no/bil---mc/bil...empemateriale-for-hoyttalere-5-stk-2000018639

It's cheap, readily available, made from polyurethane. and I thought the egg crate pattern would perhaps work in place of holes, since I will have to attach it to the inside of these speaker grills, I will have to cut away varying amounts on the crate peaks. Whatever foam is left will not be very thick.
Gitter Hifi 12 - Ljudia

Do you know where I can look for the melamine foam?
 
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Polyurethane open cell fire retardant foam works, not quite as good a spec as melamine, you should be able to find that a lot more available and cheaper, if you buy a big sheet of 10mm then you can layer it between 2 very open grills.

These people will cut a sheet down, not sure i they will sell part sheets as they cut it themselves off of a big block:

Grey Melamine Foam Sheets 1200MM X 1200MM X 25MM - Acoustafoam

This ebay seller is cheap but only in 25mm thickness but still doable if will post to you:

6 Tiles Acoustic Absorption Melamine Foam Panel Sound Treatment | eBay

Another place to try:
Melamine Foam – Wilhams Insulation


2 packs would more than do it, although you would have to go with either 50mm or 75mm, but again doable.

You could try felt but I'm guessing it will absorb more of the low mid before the highs are dealt with, rockwool will likely absorb to much of the low mid from the specs I've seen but might work.

As you have the felt, could you not try a couple of layers taped over one of your 15-300tc's?
 
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... Those magic cleaning sponges are made from melamine, and I can get them very cheap, everywhere. I will grab a pack and try out on the 12-250TC when they get here maybe early next week, just ordered the drivers and grills + some cheap compact led lights.

We are in a moving house process, and my beloved FC152 are packed away for another two horrible weeks... Temporarily replaced with some MA 10.2 and a couple Beyma 12BR70, not compareable at all! Much worse off axis, lacks detail, and for the "un-initiated" bass may seem impressive, but completely lacking the highly addictive dynamic sound of my 6x15" setup...
 
I'm out of cash, just bought water filters and proper first aid kits (not a humanitarian effort, just stuff they actually do not have there).

And the ASX50 is 22watts in 8ohm, so then I might as well just bring a couple TPA3250 as backup/plan B, because they're so nice and compact, and also just sitting on my shelf.
But thank you for mentioning it, ASX50 are nice Class D modules and it's a reasonable price.
 
SubSoniks, I ordered 18 small sheets of melamine foam, 400*300*25mm
18 Tiles Acoustic Absorption Melamine Foam Panel Sound Treatment | eBay

The cheapest I could find, useable size, melamine foam that ships to Norway.

Norway is like the backwoods in terms of international shipping, crazy expensive and halfway outside the EU postal and trade regulations... We are part of European Economical Area, but not European Union.
European Economic Area - Wikipedia

So not everyone on Ebay send stuff here.

Anyway, you want me to have a double layer of these boards, the one closest to the 12-250TC should have a hole roughly slightly smaller than the big wizzer, and the outer layer closest to the grill should have a hole slightly smaller than the size of the small wizzer?
 
Large hole equal to diameter of the large whizzer, the small hole can be anything from 25mm - 100mm, depends on loss v dispersion of HF, ideally try both 2 layers and three layers with different hole sizes. I am currently going from 125mm to 25mm over a 65mm thickness of foam.
 
Indonesia isn't such a backwards country anymore. IMO not much to find in Norway which isn't available in Bali!! just saying. Denpasar has PA specialists and buying local will make future repairs way more simple. An example of local stuff see: Contact – X9PROAUDIO

I'm not saying Indonesia is a backwards country. People just have different priorities due to income and time restrictions.
I know there's electronics stuff around, but it's more expensive and smaller selection. And I see no reasonably priced alternative to the design I will make with the Fane 12-250TC.

The reason I wanted to ask in the PA section was that perhaps someone had experience making cheap but loud diy setups, now I've learned that the PA section is more about off the shelf stuff.

And I am keeping myself well away from Denpasar, I put more value on my time than using it to stand still in traffic. Will get a local woodworker to make the boxes in Bangli or closer to Kintamani, support local craftsmen for sure.
 
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.

I somewhat agree, but in many Germanic languages and for instance in Norwegian the term "Spredning" can be used, perhaps in correlation with "vinkel", so "Spredningsvinkel". I guess the more accurate translations would actually be "Spread" and "angle", so "Spread-angle" or "cover-angle" may seem like a good word.
However, I feel that this is not the most optimal use of words, because the "spreading" of sound is never uniform, and you also have increasingly higher loss of sound in relation to distance for higher frequencies/lower frequencies go further, this might suggest that there is actually some form of "dispersion" going on (fluid dynamics, gases etc).

I understand that the term "cover-angle" *could* be used as a term, especially in relation to PA where you're looking to "cover" a specific area with sound, but somehow I do not see it as an accurate enough description for what sound is, and does.

Maybe we should have a more in-depth discussion of this topic.
 
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I do believe norvegian is euroasian and stems alot from horsepeople migrated via the silkroad from what is now known as Afghanistan akording to newer studies. The same thing with. Viking culture and mythology. Only their original Thor had a thunderbolt instead of a hammer. Sirry for way off topic
 

ICG

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The A800 has no fan = silent operation, and it has balanced + unbalanced inputs and Speakon + screw terminals for backup.

If someone manages to screw up and break stuff, I see value in the seemingly redundant connectivity options of the A800, as well as less chance of failure should something happen to the fan and some failsafe circuit on the NX1000D engages.

The connectivity is an argument but on the other hand, you have to use real brute force to kill the XLR plugs. If they poop out, the RCAs will be gone long before.

Bali can get quite hot. Most amplifiers are not made to work in tropical conditions and will have big problems dissipating the heat. I'd really suggest to add a fan on each side and probably for the power supply too. That applies not only to the A800 but to all amps.

And the ASX50 is 22watts in 8ohm, so then I might as well just bring a couple TPA3250 as backup/plan B, because they're so nice and compact, and also just sitting on my shelf.
But thank you for mentioning it, ASX50 are nice Class D modules and it's a reasonable price.

Well, maybe bring a few fans too and buck converters. Both are pretty cheap and with adjusting the voltage you can reduce the noise even of cheap fans a lot, most of the cases to not being audible.
 
I expect the XLR sockets to last forever, the XLR sockets would be the natural backup in any case. The RCA sockets are the most likely to be used, and the most likely to be abused... Not really expecting brute force to be applied, but I've learned to expect the unexpected.

Not that hot in Bali, at least not in Kintamani, last time I was there it was mostly between 15-20c indoors, even in the hotter areas it's not too bad. Think "room temperature" and you're not that far off. Houses are built to cool, as opposed to here where houses are built to insulate.
 

ICG

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Joined 2007
I expect the XLR sockets to last forever, the XLR sockets would be the natural backup in any case. The RCA sockets are the most likely to be used, and the most likely to be abused... Not really expecting brute force to be applied, but I've learned to expect the unexpected.

Yes, it's more likely on the XLRs the cables will break much sooner than the socket or plugs. And I agree, it's even more likely the RCAs will be killed rather earlier than later.

Not that hot in Bali, at least not in Kintamani, last time I was there it was mostly between 15-20c indoors, even in the hotter areas it's not too bad. Think "room temperature" and you're not that far off. Houses are built to cool, as opposed to here where houses are built to insulate.

Okay, but that brings another issue with it because it's less than 20km away from the coast, you'll likely have to deal with salty air, which reduces the lifespan of electronics vastly.
 
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