Silver Member Username: ScubasteveAnnapolis, MD Post Number: 481 Registered: May-05 | The last time I posted this it dissapeared so i'll try it again. Anyone know if there's any reason why I should't buy a pyramid power supply? I want it for testing amplifiers and for running a car sub in my room. Its pretty cheap and I was wondering if any reliability issues with it would hurt my ability to accurately test amps. Also, are there any better brands that I should check out? www.ebay.com item number: 5803463317 |
Gold Member Username: CarguyPost Number: 4136 Registered: Nov-04 | No, unlike in car audio, Pyramid in power supply is actually good. I have one that I purchased 15 years ago and still using it. |
Silver Member Username: ScubasteveAnnapolis, MD Post Number: 486 Registered: May-05 | I'm starting to think I'll regret not getting a power supply with more than 40 amps continuous. Do you know of a company that makes good power supplies that produce up to around 80 amps so I can test amps in the kilowatt range? |
Gold Member Username: CarguyPost Number: 4146 Registered: Nov-04 | It'll cost you hundreds of dollars. Orion had 100A ps on sale last year and it sold for over $500. The problem with high current ps is, there is no market for it. Just what are you trying to do? Car amps convert 12v into higher voltage. You can bypass the regulator and supply 36v - 58v, or whatever the amp needed. At that voltage, you don't need 80A. |
Gold Member Username: GlasswolfWisteria, Lane USA Post Number: 9732 Registered: Dec-03 | make sure it's a regulated, switching power supply, and be sure 50A is the continuous rating and not peak. they like to use peak ratings which are only good for momentary bursts with those AC to DC units. otherwise go for it. |
Silver Member Username: ScubasteveAnnapolis, MD Post Number: 488 Registered: May-05 | Thats the thing, the biggest pyramid power supply is 40 amps continuous and 50 peak. Also, i can't use it to bypass the amp's power supply because the pyriamid can be adjusted from 12 to 15, but no higher. |
Gold Member Username: CarguyPost Number: 4148 Registered: Nov-04 | I was talking about making your own ps. The electronic parts stores sell 38v - 58v ac transformers with 10A - 30A. 38v x 15A = 570W 12v x 47.5A = 570w. As you can see, the higher you go in volts, less current you need to produce same amount of power. FYI, 40A @ 12 is good enough for testing audio amps. That is how I test my amps at home. I just had a great idea. Get yourself a car battery charger. They have some that are 225A. Add 5F capacitor to it and you got yourself a high current and smooth DC generator. It's much cheaper than looking for 60A ps. |
Silver Member Username: ScubasteveAnnapolis, MD Post Number: 490 Registered: May-05 | I did a little more looking around and I found an 80 Amp continuous Pyramid ps that looks pretty beastly but it goes for $400 online. But if I can use 40 amps to test 99% of the amps I would come across at some impedence load I think I'll do that and save myself a good amount of money. Most of the car battery chargers I've seen are of the trickle charge variety, on the order of 10 amps or so, but I'll look a little bit more just to make sure there isn't one out there fairly cheaply that will put out 100 amps when called for. |
Gold Member Username: CarguyPost Number: 4168 Registered: Nov-04 | In Canada, the Crappy Tires (known as Canadian Tires) sells 225A fast charger/starter for $200 CDN. I got it on sale for $150. That thing will put out 60A continuous 225A for a short period of time. With a 1F capacitor, the power is smooth. I think Walmart has something similar. |
Silver Member Username: ScubasteveAnnapolis, MD Post Number: 495 Registered: May-05 | I've never stepped foot into a Walmart, but your tempting me and I don't like it. I'll see what I can find around. |