Amp experts come in plz

[Sundownhoe]

Well hi there new to forum and well ur gonna be seeing me posting here from now on lol i currently picked up a db drive 2500.1 a7 amp and well iam running it with 2 xs batteries and i think its not strong enough

So my question is if anyone of you all know the true rms on these?? Help will be apreciated!

Click to read more...

 

[mylows10 5,000+ posts]

You need to clamp the amp

 

[Sundownhoe]

More details plz not to related with these amps

 

[mylows10 5,000+ posts]

You need a clamp meter with a max hold and a multimeter with max hold. Set the clamp meter at ac amperage and multimeter at ac voltage probes in the pos and neg speaker wires and the clamp around the pos speaker wire make sure the arrow on th clamp is pointed towards the sub box or the natural flow of the current Multiply the readings when you burp or play music. That should give rms wattage

 

[Sundownhoe]

Thnkx

 

[shizzzon 10+ year member]

Its called an ammeter and multiplying both will give you VA, not wattage.

 

[negolien]

Here's a great resource for you..

Ohm's Law Calculators and Formulas

 

[n2audio 5,000+ posts]

Its called an ammeter and multiplying both will give you VA, not wattage.

I trust that you are smart enough to recognize that in this situation they are essentially the same thing.

But it sure makes you look smart to point out that technically, they are not.

SDhoe, the internals appear identical to the crescendo 2000d, and q1-2200d. So I would say just short of rated if you have the elect to support it.

 

[trumpet 5,000+ posts]

I trust that you are smart enough to recognize that in this situation they are essentially the same thing.But it sure makes you look smart to point out that technically, they are not.

I stay out of the amplifier "clamping" scene as it's not a technique I use as either as a salesman or a technician, but it's a fact that Volt-Amps are not equivalent to watts. I recognize that forum folks like to compare clamp test results, and it has been argued that since it's more or less the standard then there is some use for that test. That said, I can't ignore scientific fact because it's the entire basis of audio reproduction.

"Clamping" method VS Amp Dyno - D'Amore Engineering - High Quality Car Audio Installation Tools & Accessories - SMD Forum

After speaking with dB Drive about the A7M amplifiers, I know their published power ratings are not RMS. In other words, it's an arbitrary figure they state as an assumption that with music playing the amplifier may be able to make that power momentarily. In other words, it's a peak power rating. I don't agree with it as I'd rather see power ratings measured and published something like the pro audio industry tends to do. A "Program Power" rating makes more sense than RMS.

 

[n2audio 5,000+ posts]

The spec on their site is 2.5k at 1 -- it should be in that ballpark.

And again -- while it IS a fact that va isn't power, it is also a fact that for this measurement they are "essentially" the same.

There would be less than 1/2% difference in the two.

 

[shizzzon 10+ year member]

Less than 0.5% difference? lol..

You do realize people do not take into account temperature, DC voltage, THD level, phase angle, etc..

All all that equates to 0.5%? No.. This is wrong information.

Driving an amplifier into above or below controlled variables will net Much more than 0.5% difference.

Just look at THD alone when driven heavily into clipping.

Power ratings can jump as much as 30% and that's just ONE variable.

Forum is to help learn and understand about this hobby. Can never stop learning.

So yes, we never suggest comparing VA to watts.

IF you cannot compare apples to apples, then it's not a valid test and not worth spreading "close enough" info.

 

[n2audio 5,000+ posts]

You're annoying.

Nobody is trying to perform brain surgery. Or publish technical papers on precise amplifier power measurement.

They want a semi-accurate assessment of power out of their amp.

If someone takes the measurement while the amp is clipping, that would obviously negate the test.

I may not have the in-depth knowledge regarding electronics tech that you seem to have, but on the other hand -- some people can't see the forest through all the trees.

 

[shizzzon 10+ year member]

If they want a semi accurate measurement, then they SHOULD measure with clipping as thats usually what happens when playing music.

If annoying is educating then maybe this hobby isnt for you.

 

[negolien]

yeah knowledge is good but your coming across like a douche just saying.

 

[shizzzon 10+ year member]

I'm not so if you interpret it that way, it's not my doing.