B&K amp specs are "greek to me"

[gcmarshall]

below are the specs for the B&K Reference 200.5 amplifier. what should i make of these specs? for example, among other things that are "greek to me", i always thought a better representation of an amps true power rating was if it was rated across the 20Hz-20Khz range. the B&K's 200 wpc at 8 ohms is rated at 1Khz, as shown below. does that mean it is probably not really a 200 wpc amp? anyone with technical ability to help me decipher this mumbo-jumbo would make my day. i am seriously considering this item and mating it to a Yamaha RX-V2500. thanks.

High Power Output effortlessly drives state-of-the-art loudspeakers
High Current Capability reproduces demanding source material
Toroidal Transformers provide high current for superior dynamics
Class A Pre-driver improves low-level detail for smoother, more musical sound
Class AB MOSFET Output Stage delivers efficient, linear power
1% Metal Film Resistors reduce noise
Number of Channels 5
Power Rating 8 ohms 200W @ 1 kHz
Power Rating 4 ohms 375W @ 1 kHz
Frequency Response 5-45kHz
Dampening Factor (50Hz) 450
Input Sensitivity Unbalanced (RCA) 1.4V
Input Sensitivity Balanced (XLR) 2.8V
Input Impedance (ohms) 33.2k
THD (S+N) .09% @ 1 kHz
Slew Rate 14v/µs
Amperage (peak-to-peak) 75
Signal to Noise Ratio, A Weighted 95dB
Dynamic Headroom 1.2 dB
Line Voltage 120/220/240 VAC Switchable
Dimensions width 17" height 7.25" depth 19.25"
74 Lbs

 

[DaveOCP]

Thats one of the things I dont like about B&K. "Real" amplifiers should have 20hz-20khz ratings. Also, the S\NR rating is rather mediocre, and THD is not terribly impressive either.

 

[tdeluce]

Thats one of the things I dont like about B&K. "Real" amplifiers should have 20hz-20khz ratings. Also, the S\NR rating is rather mediocre, and THD is not terribly impressive either.

As long as the frequency band contains 20hz-20khz, why do you care?

 

[gcmarshall]

if it's not one thing, it's another. i thought i had found a good amp in this B&K 200.5. might still be good, but i would prefer that it rate its power using the "preferred" method rather than at 1Khz. everything i've read says that power rated at 1 Khz, rather than at the more accepted 20hz-20Khz, is less informative about its true capability. i am sure it must perform well; magnolia has it in their $130K demo dedicated theater room. but, it irks me that they appear to be playing games with their specs.

 

[MDS]

There a few different 'standards' for measuring amplifier power. Rating at 1 kHz is the DIN standard. The FTC requires the full bandwidth rating. EIAJ (Japan) is another, but I'm not sure of its requirements.

The numbers will always be higher for a 1 kHz vs full bandwidth rating because it's obviously easier to amplify one single frequency than it is to amplify full bandwidth pink noise [Pink noise has equal amplitude at every octave and is the type of noise a receiver's test tones emit].

B&K supposedly makes good stuff (no personal experience) but I would rather see a full bandwidth FTC rating. Even receiver manufacturers usually list both FTC and DIN ratings.