Amp for high power mobile PA

[ravels]

If you are using 8 ohm speakers, you are pretty much limited by voltage. Adding a second amp wouldn't help you at all.

You could actually connect a pair of 8-ohm speakers to each output of the TAS5630 board (for a total of 4 speakers) and get 2x225W output at 1% THD. But then you would have to use a more powerful step-up converter and may have to parallel two batteries as you would be drawing close to 50A at 12V. Basically, the amp board is not likely to be your bottleneck in your setup. You are more likely to be limited by the battery current/capacity and/or step-up converter current/power limit.

I am not familiar with the Alpine amps. They probably have built-in step-up converters. I just took a look at their product page, and PDX-F4 may be the closest product to the TAS5630 board. When you bridge the outputs of the PDX-F4, the specs look very similar to TAS5630. Who knows, maybe Alpine is using a TAS5630 chip in that amp?

 

[ICG]

Thanks a lot, that sounds quite feasable.

Would I gain something if I'd buy two TAS5630 boards, and put one in front of each speaker by paring the outputs? Would that mean I'd get 2x200W or doesn't it work to combine the two outputs of one board into a single one?

With most of these amps it's only possible to parallel bridge them. That means - as ravels already stated - gives you only more power at lower impedances but you aren't using that either. So no, that won't help you.

And how do these board compare to car amps that cost 500EUR+ for e.g. 2x300W RMS on 4 ohms (e.g. Alpine PDX)?

It's pretty much the same, don't expect an audible difference in loudness, the power is the same. Even if it would differ from, let's assume 125W on one and 150W on the other (which I doubt it would be that much difference), you'd only lose 0,76 dB. That's not audible except from a very experienced listener in direct A/B comparison in lab conditions.
I got the impression you might think double the power is double the loudness. But double the volume needs +10dB, which equals in 10x the power needed for it, +6dB means 4x the power.

I see 4 possible solutions:

1. You switch to other speakers, 4 Ohm. Or smaller tops and one or more subs, the latter preferably also 4 Ohm. Or you go for much more effective speakers (bass horns - but they will be BIG!).
2. You go for a real PA amp with class D and a 12V/220V converter (or 12V/110V, depending on where you live/buy). Even if you aren't a fan of the brand, in such a case i.e. a Behringer iNuke 3000 would be a very cheap and vialbe solution (~200-250 Euro (Thomann i.e.), 440W/8 Ohm, 880W/4 Ohm).
3. You buy an amp like in 2. and get a generator
4. You reduce your expectations to reasonable dimensions. You want to use the setup outdoors? Then you will have to yank the bass up a lot. That means though you will reach the mechanical limit of a single 15" far before you reach the power limit, outdoors you lose 6-18dB in the bass, the cone excursion gets too high too quickly once you compensate for that via equalizing. Or you need more cone surface. A 2x12" speaker might there be a solution because they usually have 4 Ohms and it's the same surface area as a single 18". Even better 2x15".

You see, the power is not the first concern at all. That leads to the real question, which is: How much spl do you really need? (Dicso volume/party/background?) How many PAX? How big is the space you want the sound on? What kind of music are you playing? (the deeper the bass, the quieter it will be at the same dimensions) Or in other words: What can be achieved with the given limits and in which you might be flexible (power, size, price).

There are also still open options, like smaller tops (10" or 8") and a DIY horn hybrid or tapped horn sub (i.e. 1 Cubo 15 or 2 MTH 30) but that derives also from your posted requirements. Or you could simply rent a mobile PA and see and try if that's enough or not and with that experience you can buy or build exactly what you need. If you don't use it regularily, renting the equipment could be better, no big sum spent, no storage space needed, cables, speaker stand etc all in one package.

 

[ICG]

[...] Or you go for much more effective speakers (bass horns - but they will be BIG!).

I meant 'efficient'. Sry, not a native speaker.

 

[Buehgemeiste]

You could actually connect a pair of 8-ohm speakers to each output of the TAS5630 board (for a total of 4 speakers) and get 2x225W output at 1% THD. But then you would have to use a more powerful step-up converter and may have to parallel two batteries as you would be drawing close to 50A at 12V. Basically, the amp board is not likely to be your bottleneck in your setup. You are more likely to be limited by the battery current/capacity and/or step-up converter current/power limit.

I would not use a step up converter.
Just use three 12v batteries in series.

 

[Eforce]

I'm building a battery powered music bike for this summer and I bought a JL Audio HD600/4 car audio amp to power my top boxes. It's a 4 channel amp rated at 2 x 300 watts into 8 ohms when bridged. I'm thinking of using the Lanzar Opti4000 on my subwoofer which is a mono amp rated at 2000 watts into 4 ohms.

 

[bitSmasher]

Hey Eforce, be sure to post a new thread with a few pics once it's together, or at least PM me some details- I'm very interested in speakers on bikes!