VMV SMSL A2 - DAC CHIP INSIDE

[JoaoPedro]

Hi.

I would like to know what is the DAC chip used in the VMV SMSL A2 (class D) amp.

I see the amp has an UBS type B input, so I assume I could use it as as an external dac, connecting it directly to my PC with the XMOS driver.

I own the DAC SMSL SU-9. I am very happy with that DAC and I would like to know if the DAC on the A2 is superior to the SU-9, or if I should still go for a separate amp and dac.

I am looking forward for your contributions.

Joao

 

[abdo123]

I don’t think there is one, i think the amplifier does digital to PWM directly without an analog conversion in between.

it’s the reason why crosstalk is great and there are no frequency dependent THD+N %

 

[JohnYang1997]

I don’t think there is one, i think the amplifier does digital to PWM directly without an analog conversion in between.

it’s the reason why crosstalk is great and there are no frequency dependent THD+N %

It may be true for the crosstalk. No frequency dependent THD+N is actually just because the noise is too high masking everything else unfortunately.

 

[abdo123]

It may be true for the crosstalk. No frequency dependent THD+N is actually just because the noise is too high masking everything else unfortunately.

so Amir wanted to capture the harmonics of the high frequencies, but unfortunately that polluted the data because it measured ultrasonic noise that we would never hear?

Eitherway i think the design is innovative and competent, with just some rough edges here and there.

 

[JohnYang1997]

so Amir wanted to capture the harmonics of the high frequencies, but unfortunately that polluted the data because it measured ultrasonic noise that we would never hear?

Eitherway i think the design is innovative and competent, with just some rough edges here and there.

Basically that's what it is. However harmonics over 20khz is not important either. A better test would be using 19+20khz(or similar) twin tone and just using 20khz bandwidth. This way you are still measuring audio signal with distortion in the audio band.

Starting around 25:00

 

[JoaoPedro]

I don’t think there is one, i think the amplifier does digital to PWM directly without an analog conversion in between.

it’s the reason why crosstalk is great and there are no frequency dependent THD+N %

What are the implications of such architecture for the sound quality?

would I be better off with the VMV A1 (class A) connected to my SMSL-SU9 DAC?

If you had to pick the main rival/ benchmark in the market for the A2 which would be?

 

[abdo123]

What are the implications of such architecture for the sound quality?

there are no implications, except that whatever DAC upstream of the amplifier is kind of useless, as Analog inputs are digitized upon entry.

It's a very neat product for someone that has no Audio electronics at all and wants an 'all-in-one' box that does everything.

If you had to pick the main rival/ benchmark in the market for the A2 which would be?

Probably a Hypex based design, something based on the NC122MP, NC252MP, the NC400 or NC502MP.

would I be better off with the VMV A1 (class A) connected to my SMSL-SU9 DAC?

Unless someone measured it I can't really comment on it as i don't own it.

 

[JohnYang1997]

What are the implications of such architecture for the sound quality?

would I be better off with the VMV A1 (class A) connected to my SMSL-SU9 DAC?

If you had to pick the main rival/ benchmark in the market for the A2 which would be?

No other than the measurement itself. Measurements from A2 and some other sources indicates much lower distortion than some other implementation using the same output stage.
There are other good performing products using modules from NCore. For example
https://www.audiosciencereview.com/...d-measurements-of-iom-ncore-pro-pwr-amp.8979/
https://www.audiosciencereview.com/forum/index.php?threads/buckeye-6-channel-amplifier-review.18579/
In the price range you are good with amps with nc252mp or nc502mp.

 

[JohnYang1997]

Unless someone measured it I can't really comment on it as i don't own it.

https://www.l7audiolab.com/f/smsl-vmv-a1/

 

[JoaoPedro]

there are no implications, except that whatever DAC upstream of the amplifier is kind of useless, as Analog inputs are digitized upon entry.

It's a very neat product for someone that has no Audio electronics at all and wants an 'all-in-one' box that does everything.



Probably a Hypex based design, something based on the NC122MP, NC252MP, the NC400 or NC502MP.



Unless someone measured it I can't really comment on it as i don't own it.

Since the upstream DAC is useless in a Class D amp, do you know of any class D alternatives to the VMV A2, that have a USB Type B connection?

I don't see them on the Hypex kits.

I will use it only connected to my PC (Hi Res audio).

 

[JohnYang1997]

Since the upstream DAC is useless in a Class D amp, do you know of any class D alternatives to the VMV A2, that have a USB Type B connection?

I don't see them on the Hypex kits.

I will use it only connected to my PC (Hi Res audio).

Class D doesn't mean it's digital. It also doesn't mean it always has a DAC in it.
NCore just like majority of designs is pure analog. You can get a relatively cheap balanced dac with superb performance to pair with it.

 

[JoaoPedro]

Any suggestions for the DAC to use with the Ncore amp?

the source will be the PC (usb Type b) and the speakers some mid-range bookshelf model (e.g KEF LS50)

Mostly for near field listening.

thank you very much for your help.

 

[AnalogSteph]

You say you have an SU-9 - that's a first-rate DAC, just keep using it. For your application I might be looking around for a NC122MP based amplifier with XLR inputs, an honest 50 wpc should be sufficient in nearfield (but also consider NC252MP options if the price difference remains moderate, that's twice the maximum power after all).