The Beast...dream to reality.

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Looks interesting. Have you given much thought on how you are going to power your beast? A normal 15A household line will only deliver at most 1800W into 8 ohms, and that is with a 100% efficient amp. You'll probably need two household circuits for each channel of your amp, if you don't want to trip your breakers on loud transients.

you sure know how to hype your projects!
Anything "special" about your circuit besides 'raw power'?
Who is your heatsink 'dealer'?

1800W? that's all? Where I am from it's 3kW upgradeable to 6kW. I would agree with you that with 1800W continuous you would need a dedicated line, breaker and plug.
Re: power supply

dutch diy said:
One solution is to use
multiple toriod / rectifier bridge combinations to
load the [presumably] huge capacitor bank and supply each toroid with its own mains plug.
Gryphon Audio Designs had this solution in one of its amp which btw needed water-cooling also.

Bingo. Nailed it :) Power supply is 4 Plitron 1500W toroids, separate plugs, wired in parallel to two capacitor rails that drive all four amps. Plugs into 4 separate circuits when used at full power. Each channel is a special bridged Leach SuperAmp. Capacitors rails are (each) 16 times 15,000uF, rail voltage is 92V. The 32 caps store a total of 2000 to 2200 joules. Heatsinks are Aavid Extrusions, cooled by 8-12 120mm fans (working on this). The potential extrusion is over 8 feet long. The transformer turnon is staged and then the capacitors are charged initially through resistors to slow inrush at turnon. I've built several bridged Leach amps so far and am thoroughly impressed to say the least. I'll post some pictures of my last project soon, so check my site out again.

If anyone needs info on parts/suppliers/questions/etc, etc, etc on the Leach amp or me! :) I have worked on them for a long time now and have lots of info.
Who is Sam? ;)

Hey, I'm new to this forum, so I thought I'd post a little info about me. Let's see, the quick stuff: I'm an 18 year old student about to start my freshman year at the University of Texas at Austin. I've been working with audio for several years now. I built my first set of speakers with the help of my grandfather about 5 years ago (young start). In the 10th grade my dad was transferred to the middle east. I then built my first leach amplifier into a powered subwoofer in the 3 years ago. It was a JBL GT 15" subwoofer in a sealed box....mannnnn did it hit hard! :) On the move back to the US, the moving company shorted the power supply leads, so when I hooked up my stereo, the amp blew. My neighbors heard this. Clearly. :( Insurance paid for the whole box, and I used the money to build a stereo Leach amp in replacement. More info on this amp later. It powers some BIG speakers built for sound quality and frequency response. More info on these monsters later. I am now working on The Beast and a matching set of speakers. I am a AVID Diy-er and plan to stay that way....I'm majoring in Electrical Engineering through the engineering honors program....who would figure? ;) Later all....believe me, I will be back :) I LOVE COMMENTS, make my day.

-- Sam

I checked out the pictures you have up on your web page. These show some MAJOR problems. You spent lots of money on a big transformer, and big filter caps, but you destroyed their ability to function properly, by using small wire to hook everything up. I'll bet your PCBs are single-sided, 1 oz. copper.

To get the most out of your high-dollar transformer and caps, you need some serious wire connecting them. If there are multiple large caps in parallel (generally, a good idea), a set of copper buss bars (1/8" x 1") would be a good idea. Remember, every bit of power going to the speakers comes through the filter caps.

If you don't have large filter caps (200uF or larger, bypassed with .1uF) at each output device, then you should use a wire with a current-carrying capacity similar to your speaker cables. If there are large filter caps at the output devices, you can use slightly smaller wire going to the output devices.

Additionally, I see electrolytic caps with bleeder resistors (good safety idea), but I think you should bypass your cap bank with some high-quality, low ESI/ESR polypropylene capacitors (these could be on the PCB, but it's better at the filter caps; both would be best). This will significantly lower the HF content of the power.

I see that you use rail fuses with 1 wire in and 1 wire out. This part's OK, but I think you need to consider where you're putting them. Rail fuses should be located as near as possible to the largest current load (the output devices). This minimizes the length of the high-current runs.

By increasing the copper thickness on the PCB from 1 oz. to 4 oz. (or, better yet, 4 oz., double sided), you significantly decrease the resistance of your power, ground, and output traces. The easy way to double the copper thickness is to use double-sided PCBs. The main power rails, and the output rail would be duplicated. The rest of the top could be a ground-plane. This results in a cleaner output signal, and more power delivered.

NOTE: Thicker copper only helps on the power runs, and near the output devices. The ground-plane should decrease the noise of the entire circuit.

Finally, the wires from the PCB to the output appear to be of medium guage (14?). By using heavy guage wire here, you can clean the signal up still more. This should have a current-carrying capacity similar to your speaker cables.

See a pattern here? The problem is that many DIY designs use super-hefty components, but don't do a good job connecting them together. Both Douglas Self and Randy Slone have chapters in their amplifier books that go over these, and many other, construction issues. It's as important as the circuit.

Good luck on the BEAST.

Also try buying a diffrent colour wire from RED.

Even though you may know whats going on inside it only takes one small mistake on the power supply to ether dent your wallet or your amps. I bet you also get a bit of hum on that amp too, if you keep wires short and cable tyed presentation is not the only benfit you will reap.

On the beast you should try and get caps with beefy looking terminals and use bus bars, copper hopefully but where i live copper is massivly expensive. Also be VERY wary of ripple ratings (and maybe the ESL/ESR), don't be temped to by the biggest cheapest caps. Try the Evox Fifa PEH200 range (i think). I personly would forget about fitting resistors across them and fuses, but i suspect people will just tut me for being lethal. Do fit bypass caps that thoth points out
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