Maker Pro
Maker Pro

larger Class D amps

B

Bob Eld

Jan 1, 1970
0
I found this on the web:

http://www.ramseyelectronics.com/cgi-bin/commerce.exe?preadd=action&k...>http://www.ramseyelectronics.com/downloads/manuals/UAM2.pdf


Not kits but check out ICEpower from B&O. They have 100Watts to 10kW!



Ok, thanks.

Wait a minute... the TPA3001D1 is mono, huh, meaning I'll need 2 to
power 2 speakers... so that's 40W already... and wait, Class D is ~90%
efficient, vs. ~50% for class AB, right? So this will sound a bit
like an 80W Class AB system, right? (rounding the 90% to 100% to make
the math easier to do in my head)

And if I power 4 speakers, that's 80W consumed, sounding like 160W of
Class AB, right?

Hmm...
 
N

Nobody

Jan 1, 1970
0
Ok, thanks.

Wait a minute... the TPA3001D1 is mono, huh, meaning I'll need 2 to
power 2 speakers... so that's 40W already...
Right.

and wait, Class D is ~90%
efficient, vs. ~50% for class AB, right?
Right.

So this will sound a bit like an 80W Class AB system, right?

Wrong. Amplifiers are rated by the amount of power they deliver, not the
amount which they consume. A 40W class AB will consume ~80W and deliver
40W; a 40W class D will consume ~40W and deliver 40W.

If amplifiers were rated according to consumption, everyone would be
selling "1kW" amplifiers consisting of an 8W IC amp and a 1kW power
resistor ;)
 
N

Ninja

Jan 1, 1970
0
... and wait, Class D is ~90%
efficient, vs. ~50% for class AB, right? So this will sound a bit
like an 80W Class AB system, right? (rounding the 90% to 100% to make
the math easier to do in my head)

If I'm not mistaken, audio amps are usually rated by output power rather
than input power. A 40 watt amp delivers 40 watts to the speakers
(neglecting speaker impedance as it affects the output power), whether it
class D, class A or anything in between. Ninty percent efficiency vs. 50%
will save you some heat sinks and power supply capacity, but it won't give
more output power.
 
E

Eeyore

Jan 1, 1970
0
Wait a minute... the TPA3001D1 is mono, huh, meaning I'll need 2 to
power 2 speakers... so that's 40W already... and wait, Class D is ~90%
efficient, vs. ~50% for class AB, right? So this will sound a bit
like an 80W Class AB system, right?

NO.

Amplifier ratings are OUTPUT power not INPUT power, so efficiency is irrelevant to how loud they go.

Graham
 
Top