SMSL SU-2: a dumb, wasted opportunity

[john61ct]

Thanks for clarifying, in many decades of audiophile reading and discussion I've never come across that "cinch" (or chinch) term for RCA plugs/jacks. I love learning new stuff, even trivia

Google says it's a mainland Europe term, Cinch was a USA company that popularised the RCA Corp 1930's invention there, from the 60's onwards.

 

[Frunse]

Is probably because i am German (born in Kirgistan ) LOL never used the Word RCA ..... But sure read about.

 

[john61ct]

That's why I try to help you. If you were born in the Kyrgyz Republic, you should know Kirgisistan is the German name, written normally as Kyrgyzstan in English.

Kudos to you for being multi-lingual though, great efforts!

 

[Frunse]

Frunse is the capital City, called now Bishkek and there i was born ...... I was 4 when i was moved to Germany so anyway.

But the way to China was much shorter than to Germany LOL, may be my Parents did it wrong LOOOOOL Kiding

 

[PGAMiami]

I received two SU-2 today. I get a slight pop when it powers up and when it transitions from standby to on. But it’s not anywhere near a level that would damage a speaker. This is with spdif in from a WiiM Pro Plus and XLR to VTV amps that use MP252 modules.

As I intend to always leave these on, I don’t see a problem. No pops turning off or unplugging the AC or the digital coax. If the power in the house goes out, the VTV amps will not turn back on before the SU-2s.

I don’t have gear to measure the SU-2s, but they sounds quite nice with no obvious flaws.

One thing I did notice is the LED that indicates when it’s locked to a signal tends to flash on and off while music plays. Don’t know what’s causing that but it’s not audible. Perhaps the output of the WiiM Pro Plus is doing something funny. Who knows. This does bother me nonetheless. Has anyone else observed this?

Both units I got behaved exactly the same.

 

[PGAMiami]

That means the audio you're playing is -30dB and below aka to quiet for the dac detection circuit.

Its the same as the SU-1 just with some ungodly wording. Hold the power button for a second it turns on/off(red led), single press changes the input. At first it will select the sampling rate with corresponding led then switches to the selected input and locked aka audio detection pin. The locked pin will start flashing if it doesn't detect audio or you're playing something quiet -30dB. The L/R audio sync led will only flash if the stuff you're listening is -15dB or higher.

Didn’t see the until now. Thank you for explaining what the locked, l and r leds do.

 

[Frunse]

That's strange, i had an realy loud Pop in the Speaker while my Amp was on and i removed the Powercord from one off my SU-2, forgot about AMP was still on, i used the AES IN.

May be i could do some measurings this day not sure i am still moving Stuff into my new Apatrtment or Clear out my big boxes.

May be it took me longer till i have Time for.

Still huge Mess in my new Apartment Not to much space for a lot of equippment LOOOOL



Also planing it this way for all my Lab Equipment:



Need to order Aluminium Profile 30x60mm for that.

Question are:

What happen on Outs if nothing is connected and you switch on or off the DAC
What happen on Outs if AES is connected with or without GND is connected (Slave Side) too from RME Card
What happen on Outs If SPDIF or Toslink is used to an Computer or an USB Interface like MOTU UL Mk5

Also the same when Music or signals are feed in While switching it off (Power Strip connected to the DAC switchin On or Off, Standby state on or off don't bother me).

May be i need to cut off the GND Pin (AMP Side) on my XLR Analogue Connections too.

On Pro equipment they have offten an Ground Lift switch If Ground loops or Problems occure.

Ordered 3 more SU-2s for 5.2 Speaker Setup for now, for 7.2 i need to build up my new Main Speaker but thats could took some time.

 

[Frunse]

Not for this price. Thats the thing, it is supposed to be the low cost balanced dac in the market, but then they ditched the most popular input.

Please show me the DACS you know with AES in XLR Out and without USB or Bluetooth specialy with such an SINAD 123,5 dB Value! For mee it need to be Clean as possible don't bother about the absolute Sounding Warm cold or what ever. That i can Change with Filtering and used AMP's on the OUT's

I have waiting for exactly this a long Time!
For aktive Speaker Setups where you need a lot off DAC's (Don't know cheep 16 Channeld DACS, only expensive Pro Audio Interfaces)

And i used MOTU UL mk 5 before for this but goes even Further with an RME HDSPe AES Card for CamillaDSP for future Freedom up too 32 Channels

 

[Ruediger]

I think the SU-2 is great. Below 100 € by leaving out the XU316 USB, volume and remote.

Top of the line ESS9039Q2M DAC. It doesn't get better than this below ESS9039PRO IMO.

If you only use digital inputs, which doesn't really matter when crossing over from a streamer etc, it's perfect.

Balanced output XLR fixed at 4.7vrms max. needs consideration for the following amp(s), but is pretty standard.

A nobrainer upgrade unit for many chains.

 

[Frunse]

USB IN is easey and cheep to include with an eternal Box USB to SPDIF or so not realy Expensive also for an Stereo only option or use an USB Streamer from MiniDSP with I2S to anything DIY Boards like this:

Also my PC has an Toslink Out so you realy need USB?

https://www.audiophonics.fr/en/inte...al-interface-32bit-384khz-dsd128-p-13627.html

Or Anamero USB Dongle or anything other.

https://www.amazon.de/Cubilux-Optis...oij0HdNOk&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1

 

[rcstevensonaz]

I think the SU-2 is great. Below 100 € by leaving out the XU316 USB, volume and remote.

Agreed. Some of us look very long and hard to find single-purpose balanced DACs that do not include volume, remote control, etc.

Units such as SU-2 and TOPPING's D10-B are now very rare. Meanwhile, there are a massive number of DACs that "do it all" — so just get one of those if you need your DAC to act as a switching device. And please quit complaining about those very few that don't.

 

[Frunse]

Topping D10-B didn't has AES in but USB like SU-1 so SU-2 is his own kind off an Device.

 

[rcstevensonaz]

Topping D10-B didn't has AES in but USB like SU-1 so SU-2 is his own kind off an Device.

Yep, which is why the SU-2 fills an important niche... so to me, it is far from being a dumb wasted opportunity (which was the same thing a lot of folks also said about the TOPPING D10-B):

• "dumb" DAC for USB to Balanced Audio = TOPPING D10-B
• "dumb" DAC for S/PDIF & AES to Balanced Audio = SMSL SU-2

My home office audio chain is: [ upstream music sources ]* -> stereo audio mixer -> RME ADI-2 Pro -> **[ downstream listening devices ]

* DAC for upstream music sources: I need to convert from digital audio to balanced audio to flow into the stereo mixer. Some of those music sources are USB (e.g., computers), but many of them are digital sources (CD / DVD, WiiM Pro, Waxwing, etc.).

** DAC to downstream listening devices: a DAC such as SMSL SU-2 can sit in the chain to take the AES and S/PDIF optical output from my ADI-2 Pro to feed powered speakers, subwoofers, balanced headphone amps, etc.

And for each dedicated DAC (upstream chain or downstream chain), I do not need or want them to anything except convert digital audio to balanced audio at line level. I will never "switch" input channels on those DACs. And I will never adjust volume on these dedicated DAC devices because any inter-device leveling is performed on the stereo mixer and all output volume control is handled by either the ADI-2 Pro or the far-end headphone amp.

Edit: added the adjective "dumb" DAC because, to a large degree, that is exactly what I want because of how I use them in my chain.

 

[Frunse]

Yeah, i own already 6 off them and need 2 more on the Future for full 7.2 Surround full aktive Setup, there isn't anything better i could use for an Price off 900€ for 8x SU-2 (16 Channels)

My Chain:
HDMI to 4x AES Extractor (or Surroundprocessor) --> RME HDSPe AES (CamillaDSP 16x16 up to 32x32) --> 8x SU-2 --> 16 CHannels Relais based Volumecontrol --> 7x HYPEX NC122 + 2x NC250 (Work in Progress)

I am thinkink about to move all the DACS and the Volumecontrol stuff in an Big Enclousures with one Big Volumeknop and may be RC5 Based Remote on an Arduino MC.

May be also changing the Power in to new Analogue Powersupplys for the DAC'S Also 9x DC 12 V Outputs for Remote switching the Hypex Amps On and Off with Time Delays between them.

Using twistedpairaudio kind off Volumecontrol with Relais (7 Bit, 128 Steps)

Volumecontrol with some Boards i had works already on an Arduino, need to design an big PCB for all that 16 Channels.

Before i was working on with the idea to integrate it in to the AMP enclosures but i guess the new way is the better way to handel it.

 

[MCH]

, there isn't anything better i could use for an Price off 900€ for 8x SU-2 (16 Channels)

Sorry I have not been following but I am curious, why not for instance a Motu ul mk5? Simpler smaller, cheaper, excellent performance and a few channels left in case.

 

[Frunse]

Sorry I have not been following but I am curious, why not for instance a Motu ul mk5? Simpler smaller, cheaper, excellent performance and a few channels left in case.

That was my first aproach and i have 2 Motu UL mk5 here used it already on an RPI5 with CamillaDSP, but thats USB and an RPI has some qirks with HDMI IN (Channel swap and so on not sure if it is fixed for now)

Also i found that nice RME Card and the cheep SU-2 DACS with an SINAD off 123,5dB !!!

So i switched my Direction to that much more flexible and easier also Future ready for full 16 Chanel ATMOS Channel in with 2 Cards and 32 Channel Out, who knows

Its was not that conviend to setup the Motus on an Windows PC before using it on Linux!

I have waited for a Year or more for an new designed AO24 Interface but they don't released it and now i switched to that new Journey

2x MOTU 1600€ around

RME Card 900€
8x SU-2 900€

Not that much more expensive!

Also still i can use my DYI HDMI to 4x AES Extractor directly in to the HDSPe Card.

One i need still to try is using that Card on an X1 PCIe Adapter (Owned it alredy) on an RPI5 thats would be very cool if it's run !!!

But i got an HTPC Enclousures with an big TFT Display on the Front and an Intel PC in it for up to 2 Cards.

Look here:

https://www.diyaudio.com/community/...ound-digital-aktive-setup.440807/post-8319556

 

[MCH]

Just my comments/curiosity, I am sure you already went through all this yourself, not trying to convince you nor do I think other options are better

That was my first aproach and i have 2 Motu UL mk5 here used it already on an RPI5 with CamillaDSP, but thats USB and an RPI has some qirks with HDMI IN (Channel swap and so on not sure if it is fixed for now)

The channel swap issue, if it is the same I reported, is for rpi HDMI multichannel audio output, not Input. Rpi engineers acknowledged the issue but didn't seem too worried about it, but in any case, this only affects HDMI output. To the best of my knowledge, raspberry pi doesn't have HDMI input. Besides that, I am not aware of any quirk of the rpi USB, at least not the modern ones.

Also i found that nice RME Card and the cheep SU-2 DACS with an SINAD off 123,5dB !!!

When I first listened to what comes out of surround channels, I convinced myself immediately that -100 dB or worse vs -120 dB is absolutely nothing to worry about. But this is my opinion.

So i switched my Direction to that much more flexible and easier also Future ready for full 16 Chanel ATMOS Channel in with 2 Cards and 32 Channel Out, who knows

Its was not that conviend to setup the Motus on an Windows PC before using it on Linux!

I have waited for a Year or more for an new designed AO24 Interface but they don't released it and now i switched to that new Journey

2x MOTU 1600€ around

RME Card 900€
8x SU-2 900€

But 8x su-2 give you 16 channels, while one single Motu gives you 22 channels, why do you need 2 Motu?

Not that much more expensive!

Also still i can use my DYI HDMI to 4x AES Extractor directly in to the HDSPe Card.

One i need still to try is using that Card on an X1 PCIe Adapter (Owned it alredy) on an RPI5 thats would be very cool if it's run !!!

But i got an HTPC Enclousures with an big TFT Display on the Front and an Intel PC in it for up to 2 Cards.

Look here:

https://www.diyaudio.com/community/...ound-digital-aktive-setup.440807/post-8319556

 

[Frunse]

How you will get 22 Channels Out? I guess with ADAT only, but than no 96kHz anymore possible on all Channels Out.

So i used the Second for additional 6 Chanel used the First one for 10 Channel TRS Outs and connected the second on SPDIF (2Channel 96kHz) and ADAT (4 Channels for 96kHz).
Thats makes 16 Channel @ 96kHz with usable Volumeknop on both Devices for TRS Outs (So i could change the Volume to an good Level let say -15dB and fineadjust on the Source, Streamer)

So a MOTU has 10 Analogue Outs TRS
8 Channels aviable at ADAT Out (48kHz only, 4 Channels 96kHz)

2 Channels on SPDIF Out

And i gues 2 more for Headphone Out on the Frontpannel.

So even without the second Motu you need DAC's with ADAT capabillity thats also cost Money and may be Sounds different so i used an second Motu for the same Quallity on analogue Outs with TRS

But you need to know even than you has to time align this Outs, on SPDIF and ADAT there is more Latancy to the second MOTU i need to add Delays on CamillaDSP for the first MOTU Than i had all 16 Channels timealigned without drifting.

Also don't forget HDMI isn't known for less Jita so an HDSPe Card has an supression -50dB on Jita at AES Inputs i like this option a lot.

But you could also use an Vanity Pro (1600€) as an Extractor with very good Jita values.

But will measure how it will go on my Setup any day also my HDMI to 4 AES is work in Progress

Used the HDMI to i2S Board before on an RPI5 4 Channel I2S input

So i am on that journey and can't tell to much now howw all will wen't, but Stereo only it sounds already very nice and i wan't to have all Chanels at the same quality!

All Amps the same HYPEX nc122, all Speaker the Same, no special Surround speaker or Center or what ever all are the same!!! And i hope i get any day an good 7.2 Settup never need to bother about the quality.

 

[MCH]

How you will get 22 Channels Out? I guess with ADAT only, but than no 96kHz anymore possible on all Channels Out.

So i used the Second for additional 6 Chanel used the First one for 10 Channel TRS Outs and connected the second on SPDIF (2Channel 96kHz) and ADAT (4 Channels for 96kHz).
Thats makes 16 Channel @ 96kHz with usable Volumeknop on both Devices for TRS Outs (So i could change the Volume to an good Level let say -15dB and fineadjust on the Source, Streamer)

So a MOTU has 10 Analogue Outs TRS
8 Channels aviable at ADAT Out (48kHz only, 4 Channels 96kHz)

2 Channels on SPDIF Out

And i gues 2 more for Headphone Out on the Frontpannel.

So even without the second Motu you need DAC's with ADAT capabillity thats also cost Money and may be Sounds different so i used an second Motu for the same Quallity on analogue Outs with TRS

But you need to know even than you has to time align this Outs, on SPDIF and ADAT there is more Latancy to the second MOTU i need to add Delays on CamillaDSP for the first MOTU Than i had all 16 Channels timealigned without drifting.

Also don't forget HDMI isn't known for less Jita so an HDSPe Card has an supression -50dB on Jita at AES Inputs i like this option a lot.

But will measure how it will go on my Setup any day also my HDMI to 4 AES is work in Progress

Used the HDMI to i2S Board before on an RPI5 4 Channel I2S input

Correct, the UK is 10+2+8+2, you need an ADAT DAC, but there are cheap options like Audient iD14 MKII for 200 eur and a few others

 

[Frunse]

Correct, the UK is 10+2+8+2, you need an ADAT DAC, but there are cheap options like Audient iD14 MKII for 200 eur and a few others

But they will sounds may be different thats i don't wan't to bother about but anyway i will sell them soon i could

I got my 3 new SU-2 and 2 of them are slitly different the Knop on the Front is different more exposed not that Flat anymore i will open them and make an Photo from PCB let see if there are something different Version number or so.

Serialnumber changed a lot in between.

4 pieces 31162501xxxx Flat Button on the Front
2 pieces 31162602xxxx around 1mm exposed Button on the Front