MickyMcD

Toroid or centertap transformer. 240v - 12V>Rectifier>Low voltage DC. Or Switchmode Power Supply. A typical gaming ATX standard SMPS will deliver around 36A on the 12V rails. A MIDAS Heratige 3000 has (usually) two redundant supplies. We benched Murray's H3K PSU at a massive 88A on the 5V rail. What do you designate as 'usable' low voltage DC? 300amp? Well, try converting that 300A DC to 32A AC 3-phase. Have fun. Cheers, Mick

Hmmmm.....No. You don't. The reason another coil is added? F=BILsinx. Force equalds B, the magnetic field strength in Webers x I, current x Length of wire in magnetic field x sinx, the angle of wire to field direction. More wire, more force. Cut a coil, lose some force. Still goes matey. Cheers, Mick

Parrallel two 1 ohm woofers, and what do you get? A (theoretical) load of half an ohm. Parrallel two 8 ohm woofers and you get a four ohm impedance, which can be paralleled again with another two 8 ohm woofers to give you (around) 2 ohm. That's four bins off one channel. PA Amplification is designed to run multiple cabs off a single channel or amplifier to maximise usage from minimal power. Also, a true high-power amplifier such as the Crown MA5000Vz is absolutely MASSIVE in power supply size and in terms of the number of transistors per channel. My largest amplifier personally is a Peavey PV Series PV3800. It delivers 1300watts continously per channel at 4 ohms. To do so, it has 13 power transistors each side, with a power supply drawing 2980w (240v, 12.41A). Drive it at 2 ohm a side, it complains. Drive it at 1 ohm a side, BANG BANG BANG x 26. Understandable as the amplifier tries to draw a good 20A plus off a 240v feed. Not good. Car audio woofers are designed at a low impedance to get a metric dickton of power. You can happily throw 3k+ to some woofers, individually. And it is not rare to see people throwing 2k+ a coil on these drivers. The only drivers that I have ever come across in my field that can remotely and briefely handle that sort of insane power are the Peavey LowRider, ProRider (to some extent), the higher end JBL array drivers, the EV Array Drivers and the P.Audio woofers. I am sure that there are more, but still a few out of thousands. All in all, it boils down to cleaner power that is easier to supply and more useful in terms of multiple driver arrays. It's great when we can run 8 NeXO Geo-s cabs a side off one Lab.Gruppen IP6400. And yes, you CAN here the difference between an amplifier run at 8 ohm and at 2 ohm. To many it's not audible, to some it's ear splitting. And Bigpimpin, it is much easier to convert AC to DC. Four diodes and a capacitor will get you a smooth DC feed from a dirty or inconsistent AC feed. Cheers, Mick

Of course, I can see these environmental factors having significant impacts. But, an example of what we may do at work; 10 ElectroVoice P3000's in a rack in direct sunlight in Townsville, Australia (usually around 34-38 degrees celcius in the sunlight) with no rack spacing except for 1RU at the top to leave our pizza's. Those amplifiers get mighty hot, yet we have not a single amplifier go into thermal protect. Although they do a mighty good job of keeping our pizza's warm, it's great. I do agree that some may install their amplifiers in...less than ideal locations, and I do realise that the old convection cooling method is less effective than a fan forced heatsink. Do many manufacturers employ fan cooling? Lastly, taking a look at your Sundown amplifiers....I'm impressed to say the least. Cheers, Mick

Just generally warm amplifiers or do they dislike being driven like a box cart down a hill for a while? It would make sense if the amplifier is going into protect like it was described. Just something I have noticed though; why is it so common to have car audio amplifiers go into protect? If one of the RAMSA's at work protects, we all bust out torches and ladders and check absolutely everything to do with that particular amplifier, from the desk to the driver. Is it simply accepted that convection cooled 12v electronics thermally protect occasionally or is it a trend for cheaper/budget amplifiers? Cheers, Mick

I'm sorry, I can't understand a word you are saying. Try posting again and using the english language. It could indicate a great many things. Of these great many things, try looking for a loose ground point, frayed wires, shorts, shorted speaker leads, disconnected remote wire etc etc. The standard looksie around. Cheers, Mick

Well, I actually like the design of this woofer. I am quite partial to big ol' heavy slugs, neodymium drivers just don't have the raw power to my ears. Even with Professional Audio equipment, I much prefere a set of JBL 2226's to the new NEO range of JBL's. But that's just me. If anyone could please post first hand experience and/or video when it surfaces, I would appreciate it. I am looking for some drivers to mount in a large horn...... Cheers, Mick

Sounds like cheap potentiometers to me. The bane of any switch is dust. Dust in the pot is often the cause of infrasonic noise put through the system at around 1-4hz. Would make your woofer look like it's 'breathing.' Clean out the pot with Cailube. Cheers, Mick

A higher thickness guage wire with a high strand count will have less Roh, or natural resistance. The hgiher strand count and thickness of the wire assist in lowering impedance, which in turn allows for higher levels of power to be delivered through the cable, lower heat generated by the cable and a higher value of Damping Factor. Cheers, Mick

Knobgobbling Fuckmints, what in Jesus' name happened there? Those fuses failed baaaaaaadly. I really do not want to know how much current was going through that. Cheers, Mick

I do not agree with the test amplification being computerized Crown amplifiers. It is very easy to disengage the Low Cut Filter which will allow subsonic frequencies to be fed to the woofer, a hazardous practice at best. Suicide at worst. There is no proof that all amplifiers were running at the same level with the same settings at all. I would actually believe them if they ran Power Amplifiers, not all in one solutions. All on unity gain (0 db), all with a low cut filter at 25hz, with all amplifiers fed from a proper splitter, such as a foldback split or one of Klark-Tekniks splitters. Cheers, Mick

This scenario will not have too much of an impact on overall woofer effeciency in terms of db/w/m. Yes, the change of impedance and coil weight, moving mass etc will modify the Thiele-Small parameters of the driver, but not enough to be of any concern. But yes, every little thing you do to a driver will affect overall effeciency, as you are changing the Theile-Small parameters, and thus how the driver functions. Effeciency is not purely based on size. dwright27, I'm not sure. Could be useful. If you get hungry, you could just whack a pork roast on the heatsink and she'll be right as rain. Cheers, Mick

Happy birthday big man, have yourself a good one aye? Cheers, Mick

Every amplifier class (A, B, A/B, C, D, G, H), apart from Class TD (Lab.Gruppen and their amazing amplifiers!) and valve amplifiers, run more effeciently at a higher impedance. You may not think so as you get more power from an amplifier at a lower impedance, but power is not effeciency. An amplifier running at 1 ohm runs far hotter than one running at 8 ohm, and draws significant amounts of power to generate output. This heats up the transistors in the output stage, and impedes the amplifier's ability to function. That is why you will NEVER see any sort of professional speaker or speaker array lower than 2 ohm. Also, with class A, B, A/B and G-H amps, they have what is called '1/3 power.' At '1/3 power', the amplifier is creating exactly the same amount of heat in watts as it does output power. You will reach '1/3 power' faster with a low impedance load than you will a high impedance load. So yes, you will alter effeciency through resistive loading. Cheers, Mick

Sorry to be harsh mate, but it should be pretty god damn obvious. Drop two one ohm coils in, you have two one ohm coils. Drop two two ohm coils in, you have two two ohm. Cheers Mick

Two one ohm stable amplifiers, three dual coil woofers. Three coils to one amp. If dual 4 ohm woofers, final load should be approximately around the 1 ohm area. Cheers, Mick

Incorrect. All loudspeakers, bar planar magnetic drivers and coiless drivers, have formers. It's what the voice coil is mounted to. Technically, the voice coil is simply a solenoid. The solenoid is mounted to a former, or bobbin. A former is not an extension. Cheers, Mick

No worries big fella. Good to see you laying down the basics for the blokes too. Keep up the good work matey. Cheers, Mick

No, Ohm's law is Easy. Ohm's law wasn't said anywhere in that paragraph. Ohm's law is V=IR. Voltage = Current x Resistance. Cheers, Mick

Put a .5ohm load on a bridged amplifier, each side of the amp in series see's .25 ohm (roughly). The MA will not handle that. Cheers, Mick

Well, I guess the most fucked up thing for me is suffering from multiple personality disorder and having psychosis. You will just be speaking to someone, and then the most horrific visions cloud you. You see them decapitated, mutilated etc and then blink, all gone. I never knew what was real and what wasn't. Of course, sometimes you just black out when he takes control. You never know what he's done, what he's said, who he's hurt. Not much fun. Thankfully, I'm almost over it. But even still, sometimes I see things. Now that I have an amzing person to love, the things I see concerning her drive me insane. It's not often, but it still hurts. And that sucks. Then again, seeing a dude cop 240v, 250A power was pretty intense. Fucking roasted like a christmas ham. Cheers, Mick

Pick up a Peavey PV series, Crown XLS series, QSC Powerlight Series or any Crest amplifier. That shall deliver enough power to move your speakers quite nicely without moving the wallet out of the pants too much. Cheers, Mick

Geez man, you had me worried something hardcore. Great to hear you pulled through alright man, I know we all happy to have you back. Cheers, Mick

P = Power (wattage) P = work/time P = IxV (current x voltage) P = V2/R (voltage squared over resistance in ohms) V = IR (Voltage = Current x Resistance - Ohm's Law) Therefore, use a Voltmeter or preferrably a Multimeter and get the output voltage. Square that, then divide by the load impedance (resistance). You now have the power at the ouput terminal. If the amplifier is either a high output or high current design, please ensure that the multimeter is fused to prevent damage. Cheers, Mick

1. My lover crying 2. Cunts banging mic's 3. Feedback 4. Feedback 5. Feedback 6. Overly boomy, peakey systems. 7. Feedback Cheers, Mick