Class D Amplifier options in India

I'm no expert in driver design but when the sensitivity is different it is because other parameters combined make the sensitivity higher, to the question of the same driver with higher or lower sensitivity, this might not be possible as someone said, some parameters might be the same, perhaps even the basic response in a sealed box/test baffle is similar but the driver would still be different. There is no apples to apples as the differences in the drivers (including the sensitivity) would make them sound different. That said I do concur that high sensitivity systems sound different than low sensitivity ones, now obviously they were different systems so it isn't apples to apples and many other differences existed in the system other than sensitivity but the subjective difference is clear to hear for anyone. I don't think an apples to apples comparison can be made unless a manufacturer decides to develop a driver which has a low sensitivity and high sensitivity version and does their best to make them similar sounding. Maybe such drivers exist but I can't remember them. If one had to answer this question "with proof" then we can't say high sensitivity makes a driver sound different (as there is no such example of high vs low apples to apples driver comparison that I am aware of) but high sensitivity combined with certain parameters does make it sound different. This can be easily seen taking a typical hifi driver and a pro driver. Personally I am of the opinion high sensitivity matters, a lot.
 
To muddy the waters a bit, speaker sensitivity comes at a cost. You want high sensitivity, you need to sacrifice the high end. You need high frequency extension, you need to sacrifice sensitivity (assuming the driver to be a constant).

So you could build two speakers with the exact same driver, same manufacturer. One speaker has large volume allowing it to be more sensitive. The other speaker a tiny hermetically sealed box large enough to house the driver. Both will sound different. The higher sensitive speaker will suck at high frequency and the lower sensitive speaker will suck at bass.

Using speaker sensitivity as a benchmark is definitely not a criteria for judging quality when you are not stating the sensitivity for every frequency range.. Producing power is cheap now with solid state amps. You can sacrifice sensitivity to get good bass exension with good solid state amps without building a monster that occupies your room powered by amps guzzling trillions of coal power, giving you the warmth that is not required in a tropical country.

The whole thing about speaker sensitivity is ridiculous. The manufacturers never state the frequencies they used to test the speaker (is it only one frequency (usually the most sensitive one) or a set of frequencies, is it pink noise, etc.). The majority of the renowned manufacturers measure sensitivity for multiple frequencies ranging from 300Hz to 3kHz and then calculate the average sensitivity and that's it. So speaker sensitivity comparisions of two speakers should be taken with a pinch of salt.

Does Greater Sensitivity Mean Better Sound?

If you need a simple answer, it’s no. Great sensitivity rating (anything above 90dB at 1W/1m or at 2.83V/1m) doesn’t imply that the speaker can deliver excellent sound quality. If the sensitivity was the only or the decisive factor, the manufacturers would make much lighter and more sensitive drivers but that would increase the distortion and ruin the performance and sound quality. Sensitivity is just one of the things that you have to consider when buying speakers. You also have to consider their frequency response, crossover frequency, size of the woofers and tweeters and the materials they are made from, build quality of the cabinet, distortion, etc. And after all, it would be best to test them and really hear them before actually buying them. All the numbers in the specifications lists don’t mean anything if you don’t like the sound you hear.
 
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In my opinion, a high sensitivity driver is a deliberate design, usually using light cone materials. And every material used has its own distinct sound character usually. Atleast Troel's thinks so, and he's built more speakers than us combined lot.

Second is beyond my IQ level to understand, but I do remember reading something about choice of magnet material / strength / size too. So, there seem to be different design implementations in reaching that high sensitivity goal. Having said that, I have no clue if a low sensitivity driver cannot be designed to have similar voicing.
 
In my opinion, a high sensitivity driver is a deliberate design, usually using light cone materials. And every material used has its own distinct sound character usually. Atleast Troel's thinks so, and he's built more speakers than us combined lot.

Second is beyond my IQ level to understand, but I do remember reading something about choice of magnet material / strength / size too. So, there seem to be different design implementations in reaching that high sensitivity goal. Having said that, I have no clue if a low sensitivity driver cannot be designed to have similar voicing.

It's been a while but as I recall for woofers you need low mass, high motor strength for high sensitivity. Lower sensitivity drivers tend to have heavier mms, more xmax, more inductance even if motor strength is high, in some cases the motor strength is so high that even with a lot of mass the drivers are high sensitivity. With these differences (often the mass and inductance) the drivers have a rolled off top end and the character will be different. It will be difficult (as far as I know) to make a driver with the same voicing but one is high sensitivity and one is low. Certainly you can make different drivers but will they maintain all their other parameters. One other thing is that for subwoofers the low sensitivity drivers in a sealed box have a top end that is not "pushed up" like high sensitivity drivers where the top end has greater sensitivity so it seems like the low end falls off a cliff. How will you account for this? It's part of high sensitivity itself where the sensitive range is pushed up compared to the less sensitive range. When you listen to two such drivers the highly sensitive part will stand out, if you level match them then the less sensitive part will be more rolled off, what people will prefer is a different topic but the difference will be large IMO.
 
In my opinion, a high sensitivity driver is a deliberate design, usually using light cone materials. And every material used has its own distinct sound character usually. Atleast Troel's thinks so, and he's built more speakers than us combined lot.
Very true. Anything that impedes movement will result in low sensitivity and vice versa. However such free flowing moving cone cannot move fast. So one will not use a woofer for a tweeter. The tweeter driver has low sensitivity. It will require immence power to move the cone a mm compared the power required to move the woofer cone a mm. But a tweeter will be like an agile gymnast ready to spring back in a fraction of a second compared to a woofer.

Hence all speaker systems are a compromise. You use two or 3 different drivers to achieve wide frequency response. Now you have single drivers that can be an agile dancer as well as a lumbering elephant that can dance slow steps. But I have never understood how by having two different cones this can be achieved.
 
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The tweeter driver has low sensitivity. It will require immence power to move the cone a mm compared the power required to move the woofer cone a mm. But a tweeter will be like an agile gymnast ready to spring back in a fraction of a second compared to a woofer.
I am not sure if I am reading this correctly. From the specs that I have seen on conventional tweeters (silk and metal domes) sensitivity is quite high from 93-96db usually. To align them to the sensitivity of the woofer one generally uses a “pad” or a resistor.
 
The whole thing about speaker sensitivity is ridiculous.
I agree and rest my case! But not quite. I leave with this:
It is akin to 2 bottles of wine. One cheap and the other expensive. Then, in comparing them saying that the expensive/cheap one tastes different and the difference is due to it's price.
 
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I am not sure if I am reading this correctly. From the specs that I have seen on conventional tweeters (silk and metal domes) sensitivity is quite high from 93-96db usually. To align them to the sensitivity of the woofer one generally uses a “pad” or a resistor.
for which frequency that's the question. Feed a 100 Hz tone to a tweeter, the tweeter will barely tweet. Feed a 16 kHz tone to a woofer, the woofer will barely bark or woof.
 
for which frequency that's the question. Feed a 100 Hz tone to a tweeter, the tweeter will barely tweet. Feed a 16 kHz tone to a woofer, the woofer will barely bark or woof.
Yes but why are we feeding a tweeter 100hz tone ? Or why should we feed a woofer 16khz? We use drivers for the freq range they are made for. Sorry but I am bit confused.

Anyways lets not get into this further.
 
Already ordered these puppies 😂
These are available on Amazon India, and with some deals they come in under 15k with 36v adapter.

Good thing is they can be returned.

Let us know what they sound like. Could be useful as monoblock power amps for HT pre outs. The connectivity in mono seems slighty confusing in the diagrams though.
 
Let us know what they sound like. Could be useful as monoblock power amps for HT pre outs. The connectivity in mono seems slighty confusing in the diagrams though.
I already have a fosi v3 lying around, for some reason I couldn't get used to the tonality of it.
I don't have any class AB amp too now, it's class A or tubes. Maybe my ears have gotten used to the presentation by these, and I find class D dry.

Let's see how it goes, i did speak with the Aiyima admin, he was prompt enough to reply me and send a video too.

Let's see how this goes🤞
 
I already have a fosi v3 lying around, for some reason I couldn't get used to the tonality of it.
I don't have any class AB amp too now, it's class A or tubes. Maybe my ears have gotten used to the presentation by these, and I find class D dry.

Let's see how it goes, i did speak with the Aiyima admin, he was prompt enough to reply me and send a video too.

Let's see how this goes🤞
I remember buying the Cirmech Power Amp from Aliexpress- home delivered for INR 2500 (with acrylic cover & fan). It was tested by Williston Audio on youtube and gave it a thumbs up for power. It was tested to give some 70watts at 8 ohms and 100 watts at 4 ohms.
Unless I do a A/B comparison with some other amp its difficult to notice what I am missing. The tonality is indeed different from my Rotel but I am hard pressed to say that the Cirmech is inferior to the Rotel. Surely a different type of sound but not necessarily inferior. I found the difference when using with Wharfedale 220, perhaps the KEF LS50 Meta will highlight more differences.

 
How do these class D amps Fosi and Aiyima compare to a Norge in the same price range of about 10k. In terms of sound quality alone.
Have any users compared or experienced both these amps ?
 
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