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2x150W Amp module for sale

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@Erica.C
 
Eric,
One of the FFA001 amps I built and gifted to a friend has been acting up. At high listening level it will cut out for a second and continue. It driving a pair of Martin Logan Electrostatic speakers.
Bill .
Hi Bill

According to the description, the amplifier is running in overcurrent mode and will be protected and recovered soon.
It does have a lower threshold due to the output MOSFET limitations in the FFA001V3.
You can try the FFA002V2 or I can change the output MOSFET in FFA001V3 and let you try again.

Thanks,
Eric
 
For lower limits of overload or clipping initiation (red led illumination), please check post #507. This is for FFA001V3 board.
Complex music is approximated better with multitone test signal rather than single tone test signal.
George
 
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I think part of the issue with the unit clipping is when people who have not listened to loud music with no distortion they don’t realize how loud it is. Some times I drag out my sound level meter to calibrate my own brain, and also so I don’t destroy what is left of my hearing. To be honest I should be putting a clip led on these units when I build them.
Bill
 
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Hi, Randy

These amp modules implement the current/voltage limit to keep the same output for 4R(current limit)/8R(voltage limit) in stereo mode. If you run it with bridge mode and 4R load, the output wattage is the same as the 4R load in stereo mode.

FFA002 2* 300W @ 4ohm;
2*150W@2ohm;

Bridge mode= 1*300W @4ohm

PS: If you need the 600W @4ohm in bridge mode from FFA002V2, I need to modify its current threshold .

Thanks,
Eric
Eric, please confirm whether this is true: 2x 300W amp when bridged provides only 1x 300W???
 
Hi, Mike
It depends on the load. As mentioned, each amplifier output channel has its own current limit circuit. If it's 300w@4OHM, then it's just 150w@2ohm, due to the same current limit data and the formula P=I^2*R.
And, for the bridge mono output, it's 300w@4 ohm, and 600W@8 or 16 ohm,

Thanks,
Eric
 
And, for the bridge mono output, it's 300w@4 ohm, and 600W@8 or 16 ohm,
At first, it sounded weird and opposite to specs that I am used to reading, but this is actually brilliant. Great way to deliver high power and make use of DVC 4R+4R drivers with the coils in series. DVC 4R+4R is very common but usually means either 8R in series and not making use of a regular amps ability at 4R or 2R in parallel and then a lot of amps struggle with that

I am worried about when impedance varies, if the 8R driver dips low to near 4R impedance at lower frequencies, would it make for weak sounding bass as only half the power is available there, but that band wants power ramping up for "loudness" reasons
 
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Hi, Mike
It depends on the load. As mentioned, each amplifier output channel has its own current limit circuit. If it's 300w@4OHM, then it's just 150w@2ohm, due to the same current limit data and the formula P=I^2*R.
And, for the bridge mono output, it's 300w@4 ohm, and 600W@8 or 16 ohm,

Thanks,
Eric
Thanks for this info, Eric. The bridged mode is not exactly what I expected but... I will wire my subs accordingly. 👍
 
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