To all the folks here on the forum who have built, rebuilt or modified any Phase Linear amps, I would like to know which of the parameters noted below you are currently testing.
All I need are the corresponding numbers (i.e. 1a, 1b, 2a, 2b and so on).
Let me be the first to say, I am not currently testing all the parameters noted below.
As with the case with measuring damping factor, I know of at least (4) or (5) methods to do so. I have only tried one of the methods so far and am not convinced it works well with amplifiers with a high damping factor.
NOTE: Even Bob Carver had his own way of measuring damping factor which appears to be different than the methods I am currently aware of.
1.) Power Output RMS
a.) Watts per channel, both channels driven into 8 Ω 20Hz – 20kHz:
b.) Watts per channel, both channels driven into 4 Ω 20Hz – 20kHz:
2.) Power At Clipping Point
a.) Watts per channel, both channels driven into 8 Ω 20Hz- 20kHz
b.) Watts per channel, both channels driven into 4 Ω 20Hz – 20kHz:
3.) Total Harmonic Distortion (THD+N) (20Hz to 20 kHz) (4Ω and 8Ω)
a.) Maximum levels at rated output
b.) Maximum level at 1W
c.) Maximum level at 250mW
4. ) I.M. Distortion (SMPTE) (60 Hz: 7kHz=4:1)
a.) at Rated power into 8 ohms:
b.) at Rated power into 4 ohms
5.) Frequency Response
a.) at 1W +0 dB / -1 dB
or
b.) at 1V +0 dB / -1 dB
6.) Power Bandwidth
a.) Frequency Response +0 dB/ -3 dB
7.) Signal To Noise Ratio
(inputs shorted) (Ref. Rated output)
a.) Unweighted
b.) A weighted
8.) Damping Factor (at 8 ohms)
a.) at 20 Hz
b.) at 1kHz
9.) Input Sensitivity (at 1 kHz)
a.) Volts RMS for rated output
10.) Slew Rate
a.) Volts per microsecond
11.) Rise Time
a.) Microseconds
12.) Phase Shift
Leading At 20 Hz
Lagging At 20 kHz
13.) Square Wave Response
a.) Tilt(%)
b.) Undershoot (%):
c.) Overshoot(%):
14.) Input Impedance
a.) Controls fully CCW
b.) Controls fully CW
15.) Channel Separation (Crosstalk) vs Frequency
(output level set at -3dB down from rated output)
a.) at 100 Hz
b.) at 1 kHz
c.) at 10 kHz
16.) Dynamic Headroom
(IHF-A-202 3.2 or CEA-490-A 5.2)
Thanks!
Ed
