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New SMSL A300 BTL Class-d Power Amp

antcollinet

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What is the max. sampling rate if I decide to connect this unit via USB, 48kHz - 16bit?
Well according to this page it has "high res certification" - whatever that is. So I suspect it can do more than 48/16.

 

MNMLSM

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Well according to this page it has "high res certification" - whatever that is. So I suspect it can do more than 48/16.

I read 48kHz yesterday on a page, can't find it right now. Let me search it again.

EDIT: got it, it's on the official page.

202206021350543113.jpg
 

antcollinet

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Looks like it's between 3-5%

Sb065e3351eb343b6aba629ea5e1554b14.jpg
It looks more like 10% to me - it is a log scale (See chart below)

A more reasonable 1% distortion would result in a power rating of around 125W

1662622299580.png
 

ftiziatr

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You don't understand something. Most likely the gain of the A300 is lower than the Denon. If so, then it would need a higher input voltage to drive it to full power.

What is the source driving the amp?


EDIT - input sensitivity Denon is 110mv, compared with 280mV for the SMSL. So the denon will give full power (40W) at 110mV, whereas the SMSL will give it's 80W at 280mV (8dB higher) since the double power is +3dB, then at the same input voltage, the A300 will give -5dB power compared with the Denon, so about 1/3 the power at the same input voltage.

Also bear in mind that the A300 80W is specified at 10%THD, whereas the denon is at 0.07%THD - so to get that extra power it has to be driven far further into clipping - it is not a like for like comparison. At low distortion (no clipping) it is more like 40W
Thank you for the quick and detailed answer. I read on the Internet and I think that the reduction in input sensitivity is made specifically for the possibility of wider volume control. Perhaps it's even better to avoid noise and sound distortion. Tell me, if I buy a second one for BTL, should it increase the volume and playback control? I use smsl sanskrit for audio output. In any case, it's much cleaner than denon. And the acoustics control is much better. The sound from the speakers with smsl has become more free and open, with denon at a higher volume it is very muddy and some sounds stick to the speakers. With denon, I haven't heard 40 percent of what I hear in headphones (I have beyerdynamic and akg) a very muddy sound, although it is perceived more powerfully and envelops you. I'm thinking of buying a second smsl for btl, I'm still worried that the volume control is 50 percent, and sometimes 70. I have kef 150, aad 550 and heco 502 speakers
 

antcollinet

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Thank you for the quick and detailed answer. I read on the Internet and I think that the reduction in input sensitivity is made specifically for the possibility of wider volume control. Perhaps it's even better to avoid noise and sound distortion. Tell me, if I buy a second one for BTL, should it increase the volume and playback control? I use smsl sanskrit for audio output. In any case, it's much cleaner than denon. And the acoustics control is much better. The sound from the speakers with smsl has become more free and open, with denon at a higher volume it is very muddy and some sounds stick to the speakers. With denon, I haven't heard 40 percent of what I hear in headphones (I have beyerdynamic and akg) a very muddy sound, although it is perceived more powerfully and envelops you. I'm thinking of buying a second smsl for btl, I'm still worried that the volume control is 50 percent, and sometimes 70. I have kef 150, aad 550 and heco 502 speakers
Well the sanskrit can output 2.2V - so it is more than capable of driving the amp to full power. What are you inputting to the Dac? If it is from a PC - is your PC "turning down" the volume output to the Dac?
 

longma

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Have anyone listened with BT. My experience is not bad. I compare (1) Oppo 205 with CD as source, RCA output to SMSL300 RCA input; (2) Pixel 6 through SMSL BT. Both with direct mode.
What i found the BT is very surprisingly enjoyable. If Oppo 205 is 10, the Pixel 6 BT is at least 7.5 to 8. The soundstage and the image from BT are not as good as the other, the details are not all there, but not bad. Btw, I dont get the same result with LG G7. Note that we need to screw the BT antenna tightly to the amp. I did not screw up tightly at first, it sounded very bad. I forgot to mention that i used Musicolet app to play the music with Pixel 6. The music is "You and Your Friend" by Dire Strait, the solo guitar at the beginning of the song is my favorite song to test any audio equipments. The speakers are Infinity Primus 162 with JBL 550 sub with HF0. Even with HF0, i still feel the sound still goes the subwoofer.
 
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Toku

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What is the max. sampling rate if I decide to connect this unit via USB, 48kHz - 16bit?
Yes, that's right, 48kHz/16bit.
The reason is that the USB input uses the D/A conversion function of the BT module and converts it to an analog signal.
Unfortunately the sound is not very good. Well, in terms of sales strategy, it is better to sell with USB and BT functions.
 

ampguy

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Curious if anyone has compared this with the Topping PA5? I have the PA5 and am pleased with it, and am looking to move more amps to Class D for power savings over time in different rooms. I like that this model has the potential to bridge (although maybe a bit kludgy without a preamp?) I also like the tone controls, at least to try out. I won't be using the built-in DAC, or the BT.
 

hueslema

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I'm a little confused about the tone and volume control which seems to be digital
This AMP works without A/D and D/A conversion even if the sub out and / or the tone control is used ?
If not, a dedicated DAC would not make sence..right?
 

Kikon

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I'm a little confused about the tone and volume control which seems to be digital
This AMP works without A/D and D/A conversion even if the sub out and / or the tone control is used ?
If not, a dedicated DAC would not make sence..right?
The controls are digital, and I understand your doubts, but in my own experience, I have a smsl sanskrit mkii dac and it works really well , if I connect it directly to the streamer, the sound loses a tiny bit of defenition...
 

TonyJZX

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do a bit of research on how Class D works... there's heaps of PDFs already on this forum

but basically the 'digital' pcm in a dac is different from the 'digital' pwm (?) in a class D amp
 

longma

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Curious if anyone has compared this with the Topping PA5? I have the PA5 and am pleased with it, and am looking to move more amps to Class D for power savings over time in different rooms. I like that this model has the potential to bridge (although maybe a bit kludgy without a preamp?) I also like the tone controls, at least to try out. I won't be using the built-in DAC, or the BT.
iiWi Review on youtube did compare PA5 in his SMSLA300 review. He likes the A300 better. My guess A300 has more power, so it sounds fuller to him. For measurement, i think PA5 is better, but for listening, it is subjective.
 

longma

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Sound clip if anyone is interested:

The guitar at the beginning is so good. I always use the track to test any audio eequipment. Another track that i use to test the base is the Way Down Deep in Hunter by Jennifer Waynes. Thank for the sound clip.
 

Bleib

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iiWi Review on youtube did compare PA5 in his SMSLA300 review. He likes the A300 better. My guess A300 has more power, so it sounds fuller to him. For measurement, i think PA5 is better, but for listening, it is subjective.
This is why we should see measurements. We don't even know how much A300 outputs whilst being clean.
My own impression on desktop use is that PA5 has no problem defeating A300, but this could all be psychological, it's not easy to do A vs B quick enough or at the same output to really know.
 

longma

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This is why we should see measurements. We don't even know how much A300 outputs whilst being clean.
My own impression on desktop use is that PA5 has no problem defeating A300, but this could all be psychological, it's not easy to do A vs B quick enough or at the same output to really know.
The measurement does help, but i wonder, as mentioned many times in ASR, if our ears can detect the difference. What SINAD is good enough (80? 90? 100?)? If not, we are after or pay for something that are so food on paper, but give no practical benefits.

Listening is subjective as everyone knows. Most audiophiles like input direct, flat curves, but some people like a little Vshape ( in this threat, some one thinks the best setup for him is E1 with treble =2, bass=2).

I would like to see the measurement too, but it is not everything. I usually bought a device based on the reviews from some people here (e.g. Toku) or some reviews on internet that i follow, and give it a try in my modest system ( usually I buy from Amazon that has 30 day return policy if i dont like the product).

If you know what a good enough SINAD ( beyond that our ears can not detect) is, please let me know. Thanks.
 

TonyJZX

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well I mean sinad is pretty easy to answer... if your normal music is 16 bit then its 96dB... with high res music being more popular you may ask for a little more?

I do get that this is filtered thru your speakers but is it acceptable for 80dB in any modern equipment?

that's like well under 16 bit...
 

kaopad999

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iiWi Review on youtube did compare PA5 in his SMSLA300 review. He likes the A300 better. My guess A300 has more power, so it sounds fuller to him. For measurement, i think PA5 is better, but for listening, it is subjective.
Agree with that , but also it depends on which speakers you're using. Sytem matching/ synergy should never be ovelrooked.
Here's a great video on this topic.
 
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