Plate Amp Standby Current (PE 500W/1000W)

[gmikol]

Hey all--

Anybody out there with either of these amps (PE #300-806 and #300-808) care to measure standby and active idle current for me?

I'd like to know whether it makes sense to future-proof by getting the 1000W, or if I'll just be blowing a ton of standby current compared to the 500W without ever really needing the 1000W in my current setup.

Also, they list efficiency as 75%/86% (500W/1000W, respectively), but is that at max output power? Is it simply max efficiency (like it's 86% efficient at 100W output but then it goes into the toilet after that)?

If I had the equipment, I'd do these kinds of tests for the sake of the DIY community, but I'm not going to drop >$100 on a 1000W dummy load just for that. Maybe next time I'm at the surplus store...

Anyway...thanks for any help you can provide...

--Greg

[simon5]

Efficiency is usually rated at full power output yes. It's also usually the same efficiency at any power level.

[gmikol]

Originally posted by simon5
Efficiency is usually rated at full power output yes. It's also usually the same efficiency at any power level.

simon5...I don't mean to jump all over you, but that's an overly simplfied view, isn't it? I mean, there are fixed losses in the transformer and the regulator (if one exists) and the rest of the PSU. There is some Class A current even in an AB design, isn't there? So at low output power, it's terribly inefficient. It'snot significant, 'cause 20% efficiency at 10W still isn't a whole lot of power. But the question is, where's the knee in that curve? How quickly does the system approach its maximum efficiency?

Also, isn't it possible that heating of the output devices would increase losses at full output power, too? Maybe it's not appreciable, but I'd like to know...

Also, I just wanna know how much this thing will burn standing still, which is something an efficiency number will not tell me.

I guess reading National,Hypex,Tripath datasheets have spoiled me for getting all the information I need...

--Greg

[phidauex]

If you use the 'auto on' feature, that turns the sub on when it gets a signal, that should lower standby current to just a few milliamps. Whatever the number though, the standby current would be the same for the big amp as the little one. Larger amps are usually more efficient, because they have increased cooling at lower volumes, but its not a huge effect.

peace,
sam

[simon5]

Yes it's an overly simplified view. Yes there's fixed losses and class A power so not efficient at lower levels. Devices usually have more losses at higher output levels, but that's where they calculate efficiency.

I guess to know the standstill current and check the efficiency curve, you'll have to measure it yourself...

[gmikol]

Originally posted by simon5
Yes it's an overly simplified view. Yes there's fixed losses and class A power so not efficient at lower levels. Devices usually have more losses at higher output levels, but that's where they calculate efficiency.

I guess to know the standstill current and check the efficiency curve, you'll have to measure it yourself...

Like I said...I didn't mean to jump all over you. Being an engineer I sometimes get obsessed with knowing everything to 3 decimal places (or more...)

I may test it when I get one, but for now I will trust the response I got from PE which says that standby current is <10W.

This seems pretty good, as I've seen specs on cheap 1kVA toroids that have magnetic losses of >20W unloaded.

--Greg

[simon5]

Yeah I'm a future engineer myself so I understand you.

I would like to help you further but there's rarely as much information out as we would like to have in the audio market...

The subjectivity of audio keep mostly all objective documentation hidden.

We would all love to have those 7 pages specs sheets for every audio part like they give us about a simple 2N3904...