I replaced four Audiolab 8000M mono blocks with four of these to save space and energy, they actually drive my Martin Logans better than the Audiolabs and sound way cleaner so they definitely punch well above their weight.
It doesnt boost voltage at all in bridge mode! What happens it the circuit can handle 2x the amps, so you can driver lower impedance speakers. Its not at all like AB class bridge mode.
I'm sure the people at fosi are sitting at the edge of their seat hanging on every word with maximum excitement giving each other high five every time you say something good about their product that they sent you for free lol. They are already ordering you many more future shipping labels so that you can continue the same flow. This is after they get done taking notes of everything you want from their products in the future of course lol. So expect to get many more products from fosi moving forward lol.
I just wish Fosi put a mark on the faceplate so users know when the volume knob reaches unity gain. Incredibly helpful for those who use it as a power amp.
Really bad ass judgement on the subwoofer out part. Fosi kept the filter at 300hz knowing very well that the sub preout will be used for an active subwoofer. And every good active sub has a crossover these days. And range 180-300 hz provides more tighter "thhwapping" bass.
I agree that if you plan to hook up an active subwoofer having a higher frequency filter (or none at all) on the sub pre out makes more sense. However, making you sub play 300 Hz deliberately (for "thhwapping" bass) is most of the time not desirable. You can confirm this, but looking at any active subwoofer or subwoofer plate amplifier. The variable crossover frequency maxes out at 150 Hz or 200 Hz.
Actually that "300" figure got mistyped which should have been 250 hz. At that range the subwoofer gets more WOOF if of course the sub is a good one. Sometime if it goes unbearable or unlistenable (owing to reasons like room size or others) then you have that variable crossover knob at your disposal on the active sub. You can set the crossover point just according to your ear's liking. Fosi just provided that added feature. If you dont need it just leave it. No point criticizing them. But No offence meant here bro.🙏🏽
Just wanna add that I also happen to use an active external electronic sub crossover sometimes for 8 or 10 inches woofer (not subwoofer) which has the crossover maxing out at 250 hz and it provides just the right amount of slam. Some people feel that without a sub their music is incomplete so for them a sub out on the ZA3 is just so fine for them. I hardly use use subwoofer for stereo listening but still support the idea of having such a sub output.
It doesn't look ugly at all, but it's a hard pass for me. Here it costs like 580,00 before taxes, plus 520,00 (taxes) plus shipping... 1100,00+ on a subwoofer amp? No, thanks...
I disagree that the built in LPF should be lower. The ideal LPF should be set according to the speakers and the room. Hard setting it at 80hz doesn't make any sense because maybe 80hz isn't what will blend the speakers and sub together nicely. Setting it to 300hz is higher than anyone would normally set it meaning you can easily just lower it on your sub and if your sub happens to not have a LPF at least its crossed at 300hz so it isn't playing full range signal. 300Hz is the better option. Personally I'd like to see it set to 500Hz or even better have a LPF defeat switch so you can use external LPF and just have a pre amplified mono signal.
I can see your scenario being more popular indeed. I was thinking that you would use a Fosi amp in stereo mode for front channels and another Fosi amp in mono mode for a passive subwoofer. In that case a fixed setting at 300 Hz is an unfortunate choice. The idea was to incorporate as many Fosi Audio products in an audio setup.
Tried it, ordered two with 48 Volts power supply. For the money it was worth a try. What can I say, they didn't live up to expectation at all. Attached to my AE520 floorstanding speakers, I lost every detail and it sounded chaotic. Not a soundstage that makes you relax.
I am building speaker box for my own purpose . 8 inch 120Rms Woofer, fs 54 hz, Vas 27 ltre, Qts 0.4 I made the box 35 ltres and seperation given for mid and hi freequency drivers and tune the port for 39- 40 hz is that good? 15 Hz bellow the driver resonance frequncy good or bad?
Hi, I bought infinity alpha 121W 12 inch sub. RMS 250w Fs 33.5 Vas 68 Qts. 0.85 Qes 0.97 Owners manual suggest me to built ported volume of 1.6(45ltr) And port tuning of 36 Hz Is it possible to tune the port for 30 Hz is it meaningful to tune a ported box bellow Fs of the driver? Owners manual also given sealed volume of 40ltres. As the woofer has lower EBP and higher Qts i am going to built sealed one. But pls help me to resolve the doubt over ported box question. While trying softwares to resolve my doubt softweres don't show result for ported box. Because Qts exceeds Qtc of 0.7. Pls help me
My ideas: 1. Include built-in DSP in the amp, with USB/BT connectivity to control it. 2. Replace mono subwoofer output with stereo line out, with x-over and level controlled by DSP. The same DSP can be used to add a HP to the output channels, so the amp is not providing a full range signal to the main speakers when a subwoofer is being used. 3. Lose the "mono" option. Do like they do for car audio and offer automatic bridging based on connections to the outputs.
@@jaredhouseman2094 Not that much extra if it's a simple DSP to control x-over settings and perhaps an EQ channel or two. Hell, I'd pay extra just for that feature. In fact the same chip that many BT speakers use and amplifiers to provide the BT connectivity also contains a built-in DSP module, so that could be a 2 in 1 solution.
@@Grommet2007 To make that happen the sound would be digitalised to apply eq and back to analog again into the the power amp. That would ruin the sound! AD converters degrades the sound badly.
@@impuls60 That's what happens with basically every added on DSP, LOL. There will be zero degradation if done properly. And that's based on electronic engineering I did on the subject many, many years ago.
Superb video,succes în tot 👌🏼
I replaced four Audiolab 8000M mono blocks with four of these to save space and energy, they actually drive my Martin Logans better than the Audiolabs and sound way cleaner so they definitely punch well above their weight.
It doesnt boost voltage at all in bridge mode! What happens it the circuit can handle 2x the amps, so you can driver lower impedance speakers. Its not at all like AB class bridge mode.
I'm sure the people at fosi are sitting at the edge of their seat hanging on every word with maximum excitement giving each other high five every time you say something good about their product that they sent you for free lol. They are already ordering you many more future shipping labels so that you can continue the same flow. This is after they get done taking notes of everything you want from their products in the future of course lol. So expect to get many more products from fosi moving forward lol.
Not agree with the filter part. Good subs all have their own filter. Leaving it high gives you enough range to decide yourself.
I was hoping that you would provide a frequency response graph, thd, or any else more than other channels do
I just wish Fosi put a mark on the faceplate so users know when the volume knob reaches unity gain. Incredibly helpful for those who use it as a power amp.
Really bad ass judgement on the subwoofer out part. Fosi kept the filter at 300hz knowing very well that the sub preout will be used for an active subwoofer. And every good active sub has a crossover these days. And range 180-300 hz provides more tighter "thhwapping" bass.
I agree that if you plan to hook up an active subwoofer having a higher frequency filter (or none at all) on the sub pre out makes more sense. However, making you sub play 300 Hz deliberately (for "thhwapping" bass) is most of the time not desirable. You can confirm this, but looking at any active subwoofer or subwoofer plate amplifier. The variable crossover frequency maxes out at 150 Hz or 200 Hz.
Actually that "300" figure got mistyped which should have been 250 hz. At that range the subwoofer gets more WOOF if of course the sub is a good one. Sometime if it goes unbearable or unlistenable (owing to reasons like room size or others) then you have that variable crossover knob at your disposal on the active sub. You can set the crossover point just according to your ear's liking. Fosi just provided that added feature. If you dont need it just leave it. No point criticizing them. But No offence meant here bro.🙏🏽
Just wanna add that I also happen to use an active external electronic sub crossover sometimes for 8 or 10 inches woofer (not subwoofer) which has the crossover maxing out at 250 hz and it provides just the right amount of slam. Some people feel that without a sub their music is incomplete so for them a sub out on the ZA3 is just so fine for them. I hardly use use subwoofer for stereo listening but still support the idea of having such a sub output.
It doesn't look ugly at all, but it's a hard pass for me. Here it costs like 580,00 before taxes, plus 520,00 (taxes) plus shipping... 1100,00+ on a subwoofer amp? No, thanks...
I disagree that the built in LPF should be lower. The ideal LPF should be set according to the speakers and the room. Hard setting it at 80hz doesn't make any sense because maybe 80hz isn't what will blend the speakers and sub together nicely. Setting it to 300hz is higher than anyone would normally set it meaning you can easily just lower it on your sub and if your sub happens to not have a LPF at least its crossed at 300hz so it isn't playing full range signal. 300Hz is the better option. Personally I'd like to see it set to 500Hz or even better have a LPF defeat switch so you can use external LPF and just have a pre amplified mono signal.
I can see your scenario being more popular indeed. I was thinking that you would use a Fosi amp in stereo mode for front channels and another Fosi amp in mono mode for a passive subwoofer. In that case a fixed setting at 300 Hz is an unfortunate choice. The idea was to incorporate as many Fosi Audio products in an audio setup.
Tried it, ordered two with 48 Volts power supply. For the money it was worth a try. What can I say, they didn't live up to expectation at all. Attached to my AE520 floorstanding speakers, I lost every detail and it sounded chaotic. Not a soundstage that makes you relax.
I disagree .. I ditched my $4 k bryston for a pair of these and sparkos opamps .. pocketed the change after selling the bryston . Happy days !!
salut! de unde l-ai achizitionat? ma uit dupa el de cateva zile si nu il prea gasesc in romania fara ca pretul sa fie exagerat
Incearca la ei pe site, pe amazon sau pe aliexpress
E de vânzare? aș vrea să-l achiziționez...sunt interesat!!!@@AudioJudgement
Sunt interesst sa-l cumpar!!!
I am building speaker box for my own purpose .
8 inch 120Rms Woofer, fs 54 hz, Vas 27 ltre, Qts 0.4
I made the box 35 ltres and seperation given for mid and hi freequency drivers and tune the port for 39- 40 hz is that good? 15 Hz bellow the driver resonance frequncy good or bad?
Hi,
I bought infinity alpha 121W 12 inch sub.
RMS 250w
Fs 33.5
Vas 68
Qts. 0.85
Qes 0.97
Owners manual suggest me to built ported volume of 1.6(45ltr)
And port tuning of 36 Hz
Is it possible to tune the port for 30 Hz is it meaningful to tune a ported box bellow Fs of the driver?
Owners manual also given sealed volume of 40ltres.
As the woofer has lower EBP and higher Qts i am going to built sealed one.
But pls help me to resolve the doubt over ported box question.
While trying softwares to resolve my doubt softweres don't show result for ported box. Because Qts exceeds Qtc of 0.7. Pls help me
Great. You do have a big point when a product gets too hyped. But I would love great mono blocks that are good enough and affordable.
My ideas:
1. Include built-in DSP in the amp, with USB/BT connectivity to control it.
2. Replace mono subwoofer output with stereo line out, with x-over and level controlled by DSP. The same DSP can be used to add a HP to the output channels, so the amp is not providing a full range signal to the main speakers when a subwoofer is being used.
3. Lose the "mono" option. Do like they do for car audio and offer automatic bridging based on connections to the outputs.
At the price, it's a nice power amp. If you add dsp, it's going to have to get a lot more expensive or a lot lower quality
But crossovers would be nice since you could one for LR and one bridged for your sub
@@jaredhouseman2094 Not that much extra if it's a simple DSP to control x-over settings and perhaps an EQ channel or two. Hell, I'd pay extra just for that feature. In fact the same chip that many BT speakers use and amplifiers to provide the BT connectivity also contains a built-in DSP module, so that could be a 2 in 1 solution.
@@Grommet2007 To make that happen the sound would be digitalised to apply eq and back to analog again into the the power amp. That would ruin the sound! AD converters degrades the sound badly.
@@impuls60 That's what happens with basically every added on DSP, LOL. There will be zero degradation if done properly. And that's based on electronic engineering I did on the subject many, many years ago.
I like 115 Greetings from Indonesia, join in learning, my master friend
I actually have four DCM. They take 900 w to push them. There are also bigger than your end table for your. Good luck with your toys on here 😢
Have one. Agree volume knob is cheap as it gets. Wire connections suck as well.
Marius you should do a build with the Dayton Audio Epiques subwoofer !!! Something like a 2 way or 3 way!!