The Boominator - another stab at the ultimate party machine

Hmmm... How do i change the input resistor on my amp, and what value is good for mobile phones and such? I'd like to get the same volume as my Computer

In the amp6basic assembly guide there is a table showing what resistors to use to have a specific gain. Look it up, i use the setting with the most powerful gain and it is perfect for my iphone.
 
Would this work? Is it okay to fit 2 wires into the same side of a butt splice as pictured in the diagram?
 

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@Saturnus
I checked the Google Sketch design of Boominator II. I see the centerpiece with allot of holes in it. The original design was without the centerpiece where the HP-10 was touching each other (is there a Google Sketch of the original one as well ?). I have read thru all the threads here but can't seem to find what benefit these new centerpieces do. Can you elaborate ? Is it easier to assemble this way or ?

thx
 
Sorry. That was inaccurate of me. The 4.5 times was per channel. The amp9b has 4 channels and not 2 so it's actually almost 9 times as much when playing maximum volume.

However, the idle current is also much higher so it uses a lot more power than the amp6b. Let's compare:

amp6b idle: 60mA @ 12V = 0.72W
amp6b max: 350mA @12V = 4.2W (loaded with 4 Ohms drivers, 2.5W with 8 Ohms)

amp9b idle: 220mA @ 24V = 5.3W
amp9b max: 1470mA @ 24V = 35.3W (loaded with 4 Ohms drivers, 20.3W with 8 Ohms)

I'm not saying the amp9b is not a great, if not fantastic amp, but you should know it's drawbacks in that it has a much more normal power consumption compared to the amp6b which uses a miniscule amount. The amp9b uses more power in idle on 24V than an amp6b uses at full volume on 12V.

So no, I don't think your pair of 60Ah batteries will last an entire festival with an amp9b without being recharged or supplemented by solar cells.

@saturnus

How can the amp6 use only 350mA from 12V power supply and output of the amplifier deliver 2 x 25RMS.
 
Hello again, I finally got the boominator back after the paintjob.
So yesterday we had the first field test at a party.

I notice that the sound become very distorted on lower volumes than expected.
I verified that its not the speaker/box by connecting it to my home hifi system and here I can play fine to ridiculus volume levels with far less distortion than with my lepai/battery setup.

Also Ive noticed that if I max out the volume knob on the lepai the bass is non existant pretty much. Even if the source volume is turned down (not playing at max). If I lower the lepai volume knob to about 75% the bass comes back. This in itself is not a major problem the volume is far too high even at 75% when the source is maxed. But maybe it can give a hint as to what might be the cause of the distortion?

Measured voltage on the batteries today is 12.1V

I will continue testing with Trends audio amp with external pre amp (the trends audio can not reach the volumes where I have distortion issues with the lepai without a pre amp).
I will also test using regular power supply (not battery) to rule out power as the root cause of this problem.

But meanwhile it would be great if anyone had tips on what might be the problem.