Powersoft X4 real power

Pasi wrote: Peaks can be, and are there but for the very short time and hence the bass suffers. When Toasty, Dominic and me tested the XTA APA against Toasty's X4, the APA sounded like it goes an octave deeper than X4 due to more RMS power available and the ability to sustain peaks longer. This becomes very clear to understand when you think the amounts of time required for each wavelength to go through ones. 11ms for 100Hz, 22ms for 50Hz and 44ms for 25Hz. And that is only one cycle of each frequency. What if we need 3 cycles of 50Hz and amp can only sustain 33ms? 100Hz works fine, but for 50Hz we get only half of the needed time. This is in many case due to PSU design and because it has to be kept cost effective. It could be done for the full specs, but size, weight and most importantly price would go up by a lot. Other aspect is that nowadays we do understand that music is mainly peaks, and hence the full power output is not always needed and thus the SMPS can be downscaled. Why would we need 3000W for 1 minute when nothing in the real life requires that? But we do need to sustain things for bit longer than 1ms or 10ms or even 33ms in real life. And this is where the differences start to come from, and this is why old heavyweights rule for deep sub applications like roots music.

It's quite easy to measure the voltage and current on the amp in real use you know - they provide nice meters for all of it. You can do the maths yourself.

DjLeco wrote: I saw in one test that I do to the K10, showing 67-70 volts Rms and 50 amps on 2 ohms resistive load.   70 volts on 2 ohms means a maximum of 35 Arms on that dummy load, presuming the resistor value is not degrading with temperature (positive coedicient as loudspeaker voicecoil thermal compression). The powersoft measured 50 amps... That amperage value of 50 amps rms matched to 100 volts rms on 2 ohms dummy load. So, who I must believe? Ohm's law or Powersoft "software"?   That test wasn't even burst mode done.

power factor?

It is not new that Powersoft is cheating with real power figures. These large amplifiers are always stated by burst ratings, such 8:32 1KHz standard. For example the K10 can pretty close deliver their peaks with 8:32 1KHz test signal.
Continuous power levels , for example for 5 straight seconds are just a fraction of the peak ~35-40% of the peak in case of 4 Ohms load with the K10.
However the X4 (and likely the X8 too, but we did not measure that) can not deliver its specs even with 1:32 1KHz signal as well as 8:32 1KHz burst would pull down the whole amp, since its power supply can not deliver the required average power. So the difference lies in the peak to average ratios, if you have requirement of very narrow duty cycle jobs the X4 could be OK but as soon as you start to push it will collapses and loose dynamics/headroom.
The X4 is NOT the amp what I would put to front stage , even for mids (rock music usually..)

It is cheaper to build
people buy it anyways
Most people won´t notice
-> it sells.

Goal reached (from powersofts point of view)

toastyghost wrote: gen0me wrote: Why such expensive amp has cuts on psu? Would bigger psu make it sound worse? How is it related to the sound? It takes 415v or more. Or anything in between. Seems a pretty poky PSU to me. Odd thing is, we have 14. They run all sorts. And they play plenty loud for all our jobs, which are not exactly 'vanilla' shows. Hell, one X4 ran 8 scoops in Berlin on multiple shows no hassle and outplayed the JTS monoblocks no questions.

Edited by Hvedstrup - 21 June 2017 at 8:37am