SMSL M500 DAC and HP Amp Review

[USER]

Headphones tested (all around 50 ohm):
- Bose QC 35 II
- Sennheiser HD 599
- Sennheiser HD 558

A quick check of online measurements shows that the Sennheisers do not have much bass to begin with--they are roughly like the HD 600s in this way. The Bose QC 35 II does have bass and was reviewed here. I encourage you to take a look at it. Amir notes that impedance changes drastically when powered on and off. This could well affect your sound. See if turning it on and off changes things. Never rely on the single number the manufacturer gives you. It is often intentionally vague. Impedance can change throughout the frequency, especially with lower quality headphones. This is why the reviews here are useful. More, the Bose is less sensitive than you think.

Likely the cause is impedance and power mismatch. Since it is not great power-wise, Amir didn't really provide a thorough review of the M500 headphone section as he does with dedicated units so its hard to definitively see if an impedance mismatch could specifically affect the bass region. However, it was noted that the unit was underpowered. I'd just go with that. This idea of "tuning" a modern headphone amplifier to a specific sound just really isn't a thing. There's plenty of evidence in the reviews.

 

[foxxx0]

Which version of the M500 do you have (SW, HW, date) ? And how do you connect balanced headphones to 6,3mm headphone port on M500?

HW 1.2
SW 1.5

It's one of the earlier models and likely has the 3rd harmonic issue.
I've collected the flash tools, firmware files and what not, but I simply haven't found the time to open it, do some soldering and upgrade the firmware yet.

My HD660S are currently 6.3mm single ended and not balanced (yet).
I have some silicon wire, paracord and connectors here to make a custom balanced cable, but yet again - no free time yet, work has been crazy the last couple of weeks.

 

[SMSL-Mandy]

HW 1.2
SW 1.5

It's one of the earlier models and likely has the 3rd harmonic issue.
I've collected the flash tools, firmware files and what not, but I simply haven't found the time to open it, do some soldering and upgrade the firmware yet.

My HD660S are currently 6.3mm single ended and not balanced (yet).
I have some silicon wire, paracord and connectors here to make a custom balanced cable, but yet again - no free time yet, work has been crazy the last couple of weeks.

HW 1.2
It needs to send back to china for a HW upgrade to 1.3
not only can be choose by the firmware.
Where you bought it? send me the email of your address.
Thanks

 

[reddeath]

HW 1.2
It needs to send back to china for a HW upgrade to 1.3
not only can be choose by the firmware.
Where you bought it? send me the email of your address.
Thanks

Am I reading this correct? SMSL employee asks a random person on the forum, who mentioned he has M500 V1, to send it back for a replacement/upgrade to V2. This is essentially a "recall" request.
Since SMSL has all email addresses of the people who bought the products through their websites at least, why is the recall done selectively, by chance, instead of sending notification to all customers?

 

[SMSL-Mandy]

Am I reading this correct? SMSL employee asks a random person on the forum, who mentioned he has M500 V1, to send it back for a replacement/upgrade to V2. This is essentially a "recall" request.
Since SMSL has all email addresses of the people who bought the products through their websites at least, why is the recall done selectively, by chance, instead of sending notification to all customers?

This is not a recall request, I just find the customer have a upgrade requirement and want to help him for the solve the probelm.

Thanks

 

[reddeath]

This is not a recall request, I just find the customer have a upgrade requirement and want to help him for the solve the probelm.

Thanks

Could you please address my request few posts back regarding low frequencies lacking in the headphone amp on M500? Some forum users suggested hardware failure. How can this be verified, preferably without sending the unit anywhere?

 

[foxxx0]

HW 1.2
It needs to send back to china for a HW upgrade to 1.3
not only can be choose by the firmware.
Where you bought it? send me the email of your address.
Thanks

Hi Mandy, I've sent you a private message with the details. Thanks for reaching out!

 

[Veri]

Could you please address my request few posts back regarding low frequencies lacking in the headphone amp on M500?

I don't think SMSL can verify or help you without sending it in. Unless you can do measurements of your unit.

 

[reddeath]

I just saw this video:

He also mentions the "thin" sound of M500 V2 comparing to V1. Although he talks about XLR output.
He asked the question what is the difference exactly between V1 and V2.

 

[USER]

 

[amirm]

I just saw this video:

He also mentions the "thin" sound of M500 V2 comparing to V1. Although he talks about XLR output.
He asked the question what is the difference exactly between V1 and V2.

There is no such thing as "slow sound." Veil and such being there/removed is classical biased listening practices. He says the voltage output is different. He should buy a $20 meter and measure that and not speculate from listening tests. Audiophiles routinely report level differences with cables and such that are not there and can't possibly be there.

He is welcome to send me his new M500 and I will measure it.

 

[reddeath]

There is no such thing as "slow sound." Veil and such being there/removed is classical biased listening practices. He says the voltage output is different. He should buy a $20 meter and measure that and not speculate from listening tests. Audiophiles routinely report level differences with cables and such that are not there and can't possibly be there.

He is welcome to send me his new M500 and I will measure it.

Wow, nice. I just doubt he will hear about the offer. I just shared his youtube video here.

And on another matter, regarding your review, which of the tests listed measures the frequency response of the headphone amplifier in M500? I have an impression that my M500 V2 has a "thin" low frequency, comparing to other amps I have available and tested with the same headphones. I would like to dig deeper into this area and understand the test results.

 

[reddeath]

After having listened to many more sources (different songs on different streaming services and local files), I can tell that the base frequency of the integrated headphone amp is enough. I believe the term sometimes used in this situation is calling the sound "transparent". It would be nice to have an equalizer in the M500 like in the RME DACs.

 

[NorthGraves]

FYI, XMOS USB driver 5.30 is available, seems to be working fine, not that I had any issues with 5.12.

SMSL Audio Official -English

Foshan ShuangMuSanLin electronics Co., LTD. founded in 2009 which located in Shenzhen, China. And our branch company VMV Technology(HK) Company Limited registered in HK in 2013. Our company is specialized in the audio DAC, stereo headphone amplifier, power amplifier, and with own R&D...

www.smsl-audio.com

 

[NorthGraves]

XMOS USB driver 5.40 is available, installed, working fine.

https://www.smsl-audio.com/upload/portal/undefined/SMSLUSBAudioDriver.zip

 

[tlr125]

does anyone know which is the latest HW version of the device? HW 1.3 or something newer?

 

[Toku]

does anyone know which is the latest HW version of the device? HW 1.3 or something newer?

I think that 1.3 was the final HW version.

 

[Dmaumau]

Yes, it´s 1.3 HW and 1.7 SW.

Just notice that the 3rd harmonic patch do not change either one after beeing applied.

 

[NorthGraves]

XMOS USB sound driver v.5.50 is out, works fine:

https://www.smsl-audio.com/upload/portal/undefined/SMSLUSBAudioDriver.zip