Snowsky (FiiO) Retro Nano Bluetooth Reciever Measurements

[yeyeyey.ipa]

Hello everyone, my first review post here. Hope you'll like it.

This is detailed measurements of Snowsky Retro Nano bluetooth reciever that can also work as a USB DAC. It was sent to me by one of my friends.
It costs about $60 US dollars.

The battery is replaceable, which is awesome since this device is intended to use as a portable Bluetooth DAC+HP amp. It has a 450 mAh battery in a 10440 form-factor included. It is not as popular as others, but still, you can find it.

Measurement setup:

• E1DA Cosmos ADCiso Grade B set to MONO mode;
• a TrueRMS DMM;
• E1DA Cosmos Scaler used as a buffer to increase ADC input impedance;
• E1DA Cosmos Load Board.

All of my measurements were performed using USB connection.

FiiO provides us with these specs:

Let's begin with measurements!

This is Frequency response with no load applied at 96 kHz sample rate.

Nothing interesting here to comment, it is flat in audible range.

This is 1 kHz FFT @ 0 dBFS output using unbalanced jack. Since this device is limited to 16 bit, I've added 16 bit dither in generator. So, we are limited here to 16 bit in terms of noise.

The device has two gain stages. At high gain, max output is 2 Vrms @ 0 dBFS, and at low gain is 1 Vrms @ 0 dBFS.

Dynamic range is limited to 16 bit and is measured at 97.2 dB. I am sure that if there would be an option to use 32 bit output on USB, the result will be much better.

Multitone performance is good. We have about 18.3 bits of distortion free range.

This device has no choice for output filter. However, I don't see any issues with its work.

J-test shows scary distortion. My guess that it won't be audible and won't cause problems in most cases, but it's up to you to decide. I noticed that this is not unique issue to Retro Nano, Hiby W3 II also have it. I've found this article where jitter measurements of Hiby W3 II can be found. Clearly there is something to improve.

In terms of power, I measured 110 mW at high gain, and 31 mW at low gain using 32 ohm load. I only measured unbalanced output because I don't have a suitable 4.4mm - 2.5 mm adapter.

Edit:
Output impedance is measured at ~0.1 ohm. Nice!

At 300 ohm load, we have 13 mW at high gain, and 3.4 mW at low gain.

I also measured this device at 10.4 ohms load. We have 62 mW at high gain, and 2.1 mW at low gain.

Edit: I forgot to add a THD+N vs frequency measurement. Here it is.

"Cirrus hump" measurements.

@jkim noticed that devices based on CS431xx could have a "hump" visible at multitone measurements. I strongly recommend checking his post about it. So, let's test it.

FiiO added a DRE toggle in one of the recent firmware, so I checked the difference between DRE turned on and off.

In TDFD Bass vs level measurements, turning DRE off clearly shows improvement. Since this device is limited to 16 bits of range, I'm showing IMD vs level and not TD+N vs level.

In Multitone vs level measurements, it shows different distortion pattern than other CS431xx based devices. Still, DRE adds a lot of distortion.

PEQ test

I've added some filters in REW EQ section and generated a response from these filters. This became a reference.

Then I measured a frequency response with these filters uploaded to device.

And there is a mismatch! I am not sure why this is the case; hope you'll tell me.

Conclusion

I like this device a lot, it has lots of features for a small price. Performance is not the best, but decent overall. With 10 band PEQ (unfortunately not per channel) and Bluetooth capabilities I think there is little or no alternatives to it.

I hope you liked this review, and I wish you best day!

 

[nickylucker]

Thank you for this detailed review. Especially for that cheap and interesting device. Congratulations with your debut in measurements on asr!

 

[MAB]

And there is a mismatch! I am not sure why this is the case; hope you'll tell me.

It looks like the mismatch is entirely due to the shelving filters.

 

[yeyeyey.ipa]

It looks like the mismatch is entirely due to the shelving filters.

I am not sure if this is because FiiO uses different Q factor definition (like in Fabfilter Pro Q and other VST EQ plugins) or because of gain difference.

 

[MAB]

I am not sure if this is because FiiO uses different Q factor definition (like in Fabfilter Pro Q and other VST EQ plugins) or because of gain difference.

My wild guess is Q definition for the shelf filters is different. A shelf at 100Hz with Q=0.71 is very close but not quite variable slope shelf at 6dB/octave. I wildly speculate the Nano is using some form of variable slope, and you are comparing to REW's variable Q filter. You could test this out if you are really interested, otherwise, it still looks like 10 bands of useful filters!

 

[yeyeyey.ipa]

My wild guess is Q definition for the shelf filters is different. A shelf at 100Hz with Q=0.71 is very close but not quite variable slope shelf at 6dB/octave. I wildly speculate the Nano is using some form of variable slope, and you are comparing to REW's variable Q filter. You could test this out if you are really interested, otherwise, it still looks like 10 bands of useful filters!

I specifically made a 3000 Hz high shelf with Q=0.3 to test it. Looks like difference is present in gain and Q factor. I don't think that it is fatal mismatch, but still i had to point it.

 

[Bl00dWolf]

Excellent review!
I think it should be pinned on the review page

The device is really quite good.

 

[IsaacOscar]

PEQ test


I've added some filters in REW EQ section and generated a response from these filters. This became a reference.

View attachment 515930

Then I measured a frequency response with these filters uploaded to device.

View attachment 515931

And there is a mismatch! I am not sure why this is the case; hope you'll tell me.

This is a known issue with most of Fiio's devices, see:

FIIO KA15 Portable DAC & Headphone Amp Review

The volume control issue (buttons needed to be pushed twice to change volume) is now fixed with the new firmware V1.1.5,they responded quickly!Now works quite good!

www.audiosciencereview.com

TLDR: you need to multiply the Q values of shelf filters by √2.
Thanks for testing the PEQ though! Most people don't, and hence errors like this go unnoticed.

I hope you liked this review, and I wish you best day!

Wow great review! I was actually considering getting this but got the Melody instead, which seems to measure better. But if I actually had a use for bluetooth, I would have gotten the retro nano, luckily I didn't!

 

[yeyeyey.ipa]

TLDR: you need to multiply the Q values of shelf filters by √2.
Thanks for testing the PEQ though! Most people don't, and hence errors like this go unnoticed.

Thanks! So it looks like they use the definition for shelving filters like Fabfilter does, where a desired shelf filter with Q = 0.707 should have a Q ≈ 1. That makes sense.

 

[IsaacOscar]

Thanks! So it looks like they use the definition for shelving filters like Fabfilter does, where a desired shelf filter with Q = 0.707 should have a Q ≈ 1. That makes sense.

Hmm, so you're saying it might not be a bug, but is actually a reasonable behaviour?

 

[OHtaru]

Hmm, so you're saying it might not be a bug, but is actually a reasonable behaviour?

Q can have different definitions, but FIIO's actual response here is different from the curve on the PEQ web page, which is misleading.

 

[yeyeyey.ipa]

Hmm, so you're saying it might not be a bug, but is actually a reasonable behaviour?

I think it is, for example Falbfilter does the same.

 

[Jalan]

Wow great review! I was actually considering getting this but got the Melody instead, which seems to measure better. But if I actually had a use for bluetooth, I would have gotten the retro nano, luckily I didn't!

+1 for the review

So the question now : what have we that measure as good as the Melody if we need bluetooth ?

 

[confucius_zero]

Wow great review! I was actually considering getting this but got the Melody instead, which seems to measure better.

subjectivetly, the Melody also sounds much better than the Retro Nano... perhaps due to its ability to select Class AB and rolloff filters? I can't prove this though, hope some graphs can help us understand.

From what I can read on the Melody measurements. Running this board on "class H" worsens the sound.

So the question now : what have we that measure as good as the Melody if we need bluetooth ?

I prefer the BTR17 for that... hopefully, we can find some measurements of it.

 

[IsaacOscar]

perhaps due to its ability to select Class AB and rolloff filters? I can't prove this though, hope some graphs can help us understand.

I personally couldn't here a difference with any of these settings (or the DRE one).

The link I posted does contain such graphs for the Melody. But basically, Class AB is better (see the video in the Class H section); and I think the Linear Phase Fast-Rollof is slightly better (see the Frequency Response section); so those are the settings I use (I also have DRE off as I feel less distortion is more important than more dynamic range).

 

[IsaacOscar]

+1 for the review

So the question now : what have we that measure as good as the Melody if we need bluetooth ?

I don't know about measurements, but the FiiO BTR13 and BTR17 also have Bluetooth and PEQ, as does the Qudelix 5K. They're all more expensive than the Retro Nano though.

 

[fws]

That replaceable battery simply makes it the best out of portable BT DACs. Even with that Qualcomm chip limiting USB performance, I would still prefer the easy serviceability, than a bit more performance which is not as important to me for on the go use.

The question is - why can't they release Echo Mini/Echo with such?
Add BT input for system alerts (while playing from DAP's DAC/storage) from the phone (so just cheap SBC only chip to keep price low), and I would buy such a DAP off the bat.

 

[IsaacOscar]

Add BT input for system alerts (while playing from DAP's DAC/storage) from the phone (so just cheap SBC only chip to keep price low), and I would buy such a DAP off the bat.

You want to receive your phone'e notification on a DAP? Why not just use your phone then? (One of the reasons people like DAPs is that they don't like having notifications interrupting your music....)

 

[fws]

You want to receive your phone'e notification on a DAP? Why not just use your phone then? (One of the reasons people like DAPs is that they don't like having notifications interrupting your music....)

Lets make it so you can customize on your phone when and which notifications go through. I certainly wouldn't like to be spammed by everything, but I wouldn't like to miss an important call (and perhaps a text/message from family or a close friend).

One reason for a DAP would be storage, given how phones are phasing out flash cards. Other is the separate battery, ease of replacement of the battery if it would be like in Retro Nano, also smaller device is easier to take a glance on the screen, full physical controls and such - BT DACs like Retro Nano have those, but will trade off quality, and still constantly drain phone's battery due to BT transmitter constantly working. On the other hand USB DAC will be tethered to the phone - so I can't really keep the phone in a backpack, or in a bag, or on the table, while having DAC with screen and controls in my pocket.

Ideally such DAP would be everything box - work with battery removed, have build in mic for voice notes, support LDAC input for streaming, LDAC output for BT headphones, have WiFi (maybe even sim card slot?), Line Out mode with presets for 0.75/1/1.25/2Vrms, FM/AM, and play Doom But I prefer something priced like Echo Mini

Oh, and honestly, I would like it to run on 2-3x AA rather than 10440 as well
My "current" DAP runs on a single AAA, has mic, EQ, and FM/AM - would be cool to have modern all around upgrade after 20 years of use

 

[confucius_zero]

FiiO BTR13 and BTR17 also have Bluetooth and PEQ, as does the Qudelix 5K. They're all more expensive than the Retro Nano though.

There's also the TimeEar BTE-9, Hiby W4 (misleading ads saying you can disable DRE) etc... I figured BT audiophile devices that "measure + sound subjectively good" continue to be niche devices that cost the premium vs a Melody. The RetroNano is already better than the W3 I assume.

I enjoy the BTR17 enough to feel it's providing good value in the premiums I paid for it. However, there are no measurements of it yet aside from what we see on FiiO's "parameter" page.