Hello all,
while discussing some amp-issues on an event with a diesel generator, we once again went into the topic of Active PFCs in PA Amps with switch mode PSU - so I went on the yourney of gathering information... Which Amps do have a very good active PFC (which is able to almost mimic a constant load)? And since I have found only snipplets of information, I thoght it might be a good idea to start a thread, maybe make a list... ?
I am not a PSU Expert - please feel free to correct me whenever needed. If this thread makes sense and will grow, I would be happy to polish it... I will start a list of amps, I know have acive PFC that mimiks sine-type draws from the mains:
Not sure about:
All input on the issue is welcome 🙂
while discussing some amp-issues on an event with a diesel generator, we once again went into the topic of Active PFCs in PA Amps with switch mode PSU - so I went on the yourney of gathering information... Which Amps do have a very good active PFC (which is able to almost mimic a constant load)? And since I have found only snipplets of information, I thoght it might be a good idea to start a thread, maybe make a list... ?
I am not a PSU Expert - please feel free to correct me whenever needed. If this thread makes sense and will grow, I would be happy to polish it... I will start a list of amps, I know have acive PFC that mimiks sine-type draws from the mains:
- Hoellstern Amps (all models)
- PKN Controll XE and XD models
- Powersoft X-Series
- Crown DCi Series
- Camco Q-power 14
- Carvin LT Series PFC
Not sure about:
- Crown i-Tech Series
- Other Camco Models
- older/other Powersoft
All input on the issue is welcome 🙂
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If you look at the front end power supply schematics, there is your answer.
Mackie (Loud Technologies) , Crown Tech, Bose and most newer power amplifiers use a PFC.
It is a legal requirement to use a PFC for most European equipment including stepper motor driver power supplies for medical equipment.
All Sanyo LCD Projectors have used a PFC since 2001.
Mackie (Loud Technologies) , Crown Tech, Bose and most newer power amplifiers use a PFC.
It is a legal requirement to use a PFC for most European equipment including stepper motor driver power supplies for medical equipment.
All Sanyo LCD Projectors have used a PFC since 2001.
Thanx for commenting.
I would like to focus on those amps that have an active PFC, which is able to get an almost sinusodial draw from the wall (lets say around 0,9..). Those are rare and not all models from one manufacturer are alike. Crown seems to have them in iTech, XT Models don´t have them. Most Entry level Amps sold in Europe and even a lot of more expensive gear don´t have these (just simple PFCs).
A list with specific models would be the goal.
I would like to focus on those amps that have an active PFC, which is able to get an almost sinusodial draw from the wall (lets say around 0,9..). Those are rare and not all models from one manufacturer are alike. Crown seems to have them in iTech, XT Models don´t have them. Most Entry level Amps sold in Europe and even a lot of more expensive gear don´t have these (just simple PFCs).
A list with specific models would be the goal.
the new carvin 1U format power amps
besides being class D , have PFC
https://carvinaudio.com/products/lt5800-5800w-2-channel-pfc-power-amplifier?
another one 1U format
this one from ADMARK claims to work from 60v to 400V
PFC
https://www.admarksound.com/power-a.../ad442-class-d-power-amplifier-4-channel.html
besides being class D , have PFC
https://carvinaudio.com/products/lt5800-5800w-2-channel-pfc-power-amplifier?
another one 1U format
this one from ADMARK claims to work from 60v to 400V
PFC
https://www.admarksound.com/power-a.../ad442-class-d-power-amplifier-4-channel.html
correct power factor to 1 or close to 1 (0.92-0.99) so current draw is in phase with voltage sine.
It is known that linear power supply have these factor around 0.65 capacitive, so to get Watts you will draw much more VA (W=VA*power factor).
If you have diesel generator with only 1kW, you will easily reach it's max current output and overload relay will switch off output (when using power amplifier with 600W and linear PS, or SMPS without PFC). When using SMPS with PFC (or APFC) your current will be in phase and you will get maximum from the generator and amp will reach it's max power (if it is about 1000W). Current will vary with the load (loudness of your amplifier), it will not be constant load.
It is known that linear power supply have these factor around 0.65 capacitive, so to get Watts you will draw much more VA (W=VA*power factor).
If you have diesel generator with only 1kW, you will easily reach it's max current output and overload relay will switch off output (when using power amplifier with 600W and linear PS, or SMPS without PFC). When using SMPS with PFC (or APFC) your current will be in phase and you will get maximum from the generator and amp will reach it's max power (if it is about 1000W). Current will vary with the load (loudness of your amplifier), it will not be constant load.
There are different types of PFC. The ones we are after here in this thread are able to mimic a constant load (like a resistor) and draw a sinusodial load from the mains. These are active PFCs.
Thanx. The Carvin seem to have what we are looking for, added it to the list.
I did not find specifics about the admark PSU - could you point me to the info whether it has an active PFC which has a Factor above 0.9 and mimiks a sinusodial load?
I have a couple of Crown DCi series install amps, e.g. DCi 2|1250, that include active PFC in the PS section. Nice amps IMO. I picked them up used from Ebay, but they are still not "cheap" but have guaranteed power delivery into various loads down to 20Hz.
One major Amplifier manufacturer that does not use PFC is Linea Research, they have also published a white paper as to why they don't:
https://linea-research.co.uk/wp-con...sets/Tech Docs/PFC - Lineas position -01a.pdf
https://linea-research.co.uk/wp-con...sets/Tech Docs/PFC - Lineas position -01a.pdf
That is not logical. Is that have sense? Constant load means unnecessarily use of energy, where you will store or spend that energy.
SwitchModePowerSuplly are based on energy flow, what energy is needed will come out (to the load, your amp), but current for making that energy will be in phase with utilities (mains) voltage. ActivePowerFactorCorrection will with high frequency switching take current from mains in phase with voltage. Result is higher voltage in mid circuit.