# Best Power Supply for bench testing Old School amps



## MCLSOUND (Oct 21, 2011)

I am looking to buy a good 40amp(min)PS for checking these big ol amps that will eat 100 amps if you let them.
There is a refurbished Pyramid locally but there still asking $250+13%tx and 90 day warr..If I am that close I would get new but I would rather find out what to look for first.
thanks


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## bigdwiz (Oct 7, 2010)

I use Audio Authority Model 978 100A 13.8V power supplies and recently found another one by Audio Authority...the "Hybrid" 2/77 50A continuous and 300A peak! The power supply itself provides 50A and the hybrid part is adding a large starting battery (not deep cycle according to the manual) for the extra burst of amperage up to 300. I picked up the 2/77 locally off CL for $50, so keep watching local ads and eBay and you may just get lucky. Also, the 2/77 uses a standard 15A outlet plug while the Model 978's use a 20A plug. Another difference is the 978 has five 20A modules which can be replaced individually if needed, but is a switching power supply. The 2/77 is solid state with a huge power supply and weighs a TON.

As for the Pyramid power supplies, I've never used them, so I can't comment. Maybe someone else has experience with them?


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## MCLSOUND (Oct 21, 2011)

thanks B


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## smgreen20 (Oct 13, 2006)

I have a 10a right now but our local shop has a 100a he said he'd sell me for $240. Don't know the brand of either.


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## chad (Jun 30, 2005)

The pyramids don't hold up well if you intend to hammer them at their rated current.


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## ahardb0dy (Feb 19, 2012)

I have a Astron with variable voltage and amperage, mine is a 35 amp but they make them up to 70 amps


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## MCLSOUND (Oct 21, 2011)

Thanks...I figured so about Pyramid.


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## chad (Jun 30, 2005)

Watch test equipment/lab liquidations for a Lambda. I just sold mine, all 90 Lbs of it but damn, that thing was a hoss.


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## MCLSOUND (Oct 21, 2011)

thanks chad


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## bigdwiz (Oct 7, 2010)

Found you one...Ok, maybe not, but this is the one I need for my bench  


12 Volt Power Supply


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## MCLSOUND (Oct 21, 2011)

PERFECT D
A local place has a astron 70 but it is 13.8v fixed?


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## bigdwiz (Oct 7, 2010)

My Audio Authority units are all 13.8v fixed (my volt meter shows closer to 14v). It's not easy to find an over 50A P/S that's both adjustable and affordable


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## TrickyRicky (Apr 5, 2009)

bigdwiz said:


> I use Audio Authority Model 978 100A 13.8V power supplies and recently found another one by Audio Authority...the "Hybrid" 2/77 50A continuous and 300A peak! The power supply itself provides 50A and the hybrid part is adding a large starting battery (not deep cycle according to the manual) for the extra burst of amperage up to 300. I picked up the 2/77 locally off CL for $50, so keep watching local ads and eBay and you may just get lucky. Also, the 2/77 uses a standard 15A outlet plug while the Model 978's use a 20A plug. Another difference is the 978 has five 20A modules which can be replaced individually if needed, but is a switching power supply. The 2/77 is solid state with a huge power supply and weighs a TON.
> 
> As for the Pyramid power supplies, I've never used them, so I can't comment. Maybe someone else has experience with them?


I love my 2/77, never had a problem with it. I bought mine used after CircuitCity closed out. They used them to power up display models and testing models on the floor. I dont use a battery, but if I ever have to I can always buy a battery and have 300amps available.

Got mine for 125.00 shipped (this things weight atleast 50lbs). Good luck with shipping charges to Canada.


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## MCLSOUND (Oct 21, 2011)

So I decided I was going to bite the bullet on a Astron 70 when low and behold a 35 comes up for sale this very morning for one quater the price of the 70.It may not be as powerful but it will do for now


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## Old Skewl (May 30, 2011)

So did you get a 35 Amp Astron? What model? I have seen different models.


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## ahardb0dy (Feb 19, 2012)

Here is my Astron it is a VS-35M, specs say 25 amps at 13.8 volts, variable from 2-15 volts, amperage variable from 1.5 to full load. I bought this about 20 years ago and it still works perfect. The 70 amp one you saw it would depend on which model it is on whether or not the voltage is variable. The RS-A series only have an on/off switch no meters, the RS-M series have meters but not variable, the VS-M series have meters and are variable


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## minbari (Mar 3, 2011)

get 1000CCA car battery and a 80A charger, like the kind Kinetic makes. for testing, will give you 100's of amps and then recharge it.


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## TrickyRicky (Apr 5, 2009)

minbari said:


> get 1000CCA car battery and a 80A charger, like the kind Kinetic makes. for testing, will give you 100's of amps and then recharge it.


I dont know what kind of testing the OP whats to get. But just using a battery will just go to show the amplifier cuts on and produces amplification. For fully testing an amplifier (scope and sinewave generator) then you'll need a steady voltage and current supply without dropping. Also 12v batteries by themselves can't make what most power supplies can (13.5v or a bit higher). So it may depend if he can just use a battery, plus charging a battery after every amp/test will suck because you'll have to wait untill battery is fully charged.


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## minbari (Mar 3, 2011)

True, will depend on the level of testing he needs to do

Sent from my Motorola Electrify using Tapatalk


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## MCLSOUND (Oct 21, 2011)

Thanks guys
It is a rs35m and should get all the gear up and running.Maybe not doing a 1ohm load on a pair of 15" subs but should see if everything works.


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