Sure Electronics AA-AB32313 2x400

Sorry I took a kind of shortcut here : yes they state 1.27 for max scale. But most consumer preamp deliver 0.7V Rms full scale (case for mine).

And if you look at the full range of products, the lower the power supply voltage, the lower the sensivity at full range. The 2x100W version has a sensivity lower than 0.7 and already 26db gain.



Also from what I read (I am not equipped to confirm this) the way of early clipping (at least when signal it's under the true clipping threshold) mimics the behavior of a tube amp, and that's what people usually love or hate with this amp.
 
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I recently tried their 2x 200W board. I even fitted it in a well ventilated enclosure but it just didn't satisfy, me or the Mrs, or the cat 😸 maybe it didn't suit my 6 Ohm speakers much but that fan certainly didn't suit anyone here. It cut in quite regularly even at very low volume.

It might make a fairly decent PA amp but I doubt the power ratings. It could probably still make a lot of noise in a small venue though 👍
 

fvaille, it always puzzled me the way wondom states the sensitivity and the the voltage rating in a spec soup mix that does not make much sense, as they go from .7 to 1.7V ; from 30 to 50V max in PCBs that are all very similar or equal. One of the advantages of running 1.7V sensitivity with a .9V source is that you never reach the 10%+ distortion, but you loose much of the power.


davym, I had to replace the fan with a noctua and the low speed noctua resistor. before it was unsable, as it would random spin to 100% at idle times. Now it is silent. Expensive add on as the fan costs 1/4 of the cost of the amp.

 
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I use the 2x100 and 1x200 T-amp modules and I'm happy with them on a 3way active horn system.

The specs are maximums under the specified conditions,. The gain for the 2x100w is 30dB (31.6X) and I run it from 24VDC which allows the amp output to swing ~+/-24VDC peak (~17 Vrms) and with an 8Ohm load I get Pmax=(17V*17V))/8R ~= 36W . This is far short of the 100W max, but in my system it's expected based on my supply and drivers. That also means the max input is 17V/(10^1.5) ~= 0.54 Vrms before clipping. The outputs are differential (idle at Vcc/2) so I used a scope (Ch1-Ch2) to measure the amp gain, input and output and it does what its suppose to.
 
I use the 2x100 and 1x200 T-amp modules and I'm happy with them on a 3way active horn system.

The specs are maximums under the specified conditions,. The gain for the 2x100w is 30dB (31.6X) and I run it from 24VDC which allows the amp output to swing ~+/-24VDC peak (~17 Vrms) and with an 8Ohm load I get Pmax=(17V*17V))/8R ~= 36W . This is far short of the 100W max, but in my system it's expected based on my supply and drivers. That also means the max input is 17V/(10^1.5) ~= 0.54 Vrms before clipping. The outputs are differential (idle at Vcc/2) so I used a scope (Ch1-Ch2) to measure the amp gain, input and output and it does what its suppose to.
You do not get 24V peak voltage output from a 24 Volt supply. Any semi conductor crossing takes up some voltage.
With well build A/B amps, you often feed the driver stages 5-7 Volt more than the power transistors, thus you can use the full output swing and get better clipping behavior.
So you should better calculate 22 Volt peak if you have a 24 Volt supply.

Anyway, your output numbers for a 24Volt supply are correct, with roughly 30W/8Ohm at 1% THD or 60W/8Ohm

Power output at 10% THD is, even for subwoofer use, very questionable. A full range amp at 10% is maybe usefull for anouncements at a train station and has nothing to do with HIFI.
 
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I use mine (500W x1) as sub amp, but since I dive it with a .9V signal , way below the 1.7V sensitivity, I get about 150 watts clean out of it with a 40 Volts power supply, Yes, you have to take in consideration that you loose about 10% to efficiency in the classD amps. That is enough to drive my 15" 92dB driver to the limit of my room.

IMHO, with class D amps you have to get the Purify/Hypex and similar block that give you good linear performance or if you get a wondom or similar, you have to derate the unit to make sure you avoid a 10% distortion. Even a 10% distortion may not be the end of times if it is only reached in explosions or similar content on a home theater sub.
 
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You do not get 24V peak voltage output from a 24 Volt supply. Any semi conductor crossing takes up some voltage.
With well build A/B amps, you often feed the driver stages 5-7 Volt more than the power transistors, thus you can use the full output swing and get better clipping behavior.
So you should better calculate 22 Volt peak if you have a 24 Volt supply.

Anyway, your output numbers for a 24Volt supply are correct, with roughly 30W/8Ohm at 1% THD or 60W/8Ohm

Power output at 10% THD is, even for subwoofer use, very questionable. A full range amp at 10% is maybe usefull for anouncements at a train station and has nothing to do with HIFI.
Of course there are losses, both on the semi side and resistive losses. It was a quick Pmax calc, to get some ballpark numbers to see if they agreed with the spec sheet and what I measured.
 
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Finally...

Amp was not defective (tested by audiophonics). Built a new case with 2 amps + 2 DSP using a modified Meanwell RSP1000 (modified with 12" silent fans). With the standard 48V voltage and plenty of amps (1kW), works great with clean bass despite the power hungry low volume subs. DSP output is max 1V so about 250W/channel (4Ohms), far from high distortion zone.
 
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919E856C-79F4-4C4A-A4AD-C888BC30AF4C.jpeg
 
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Black power supply on the right as since been replaced with a 48V to 10V step down converfter to feed DSPs and VU-Meters.

The third output of each DSP does max(main,sub) to feed the VU-Meter, input is RCA and output is speakon 4 poles (subs are integrated into speakers). Full range to tweeter is a passive filter.

6DD81C23-F980-419A-A052-3748B780EAD0.jpeg
 
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Hello fvaille,

I changed the input caps to Mundorf Mcap Supreme Evo Oil paralleled with little Silver Mica. Quite expensive but sounds really great. I also changed the the 470uF caps to one of the best 680uF caps. So next step would be an (if there) opamp.
I think one is under the heatsink. I will have to remove it an see.

Ralf