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SMSL SU-9 Balanced DAC Review

reddie.k

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i tried but the sound is still flat

Three little "experiments"

1) Maybe use the variable preamp mode on su9 and turn it down to zero. Then turn the da9 volume all the way up. Finally start turning up the volume on su9 until the desired level.

2) Can also try the opposite. Da9 to zero, preamp mode on su9 to 99, start turning up da9.

3) Fixed preamp mode on su9, adjust volume on da9.

Which speakers have you got btw?
 

mario_rouge

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Three little "experiments"

1) Maybe use the variable preamp mode on su9 and turn it down to zero. Then turn the da9 volume all the way up. Finally start turning up the volume on su9 until the desired level.

2) Can also try the opposite. Da9 to zero, preamp mode on su9 to 99, start turning up da9.

3) Fixed preamp mode on su9, adjust volume on da9.

Which speakers have you got btw?
Thank you!
I will try.
I have Elac dbr62
 

ceausuc

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i tried but the sound is still flat

SDB mode is a night and day difference on these amps. It's almost too 'vivid' for me at normal listening levels (with too much bass).
I'm only using it when listening at very low levels. I suppose it was created for this purpose.

If you don't like that dac send it back and get something else, I doubt that playing with its volume control will change anything.
 

mario_rouge

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SDB mode is a night and day difference on these amps. It's almost too 'vivid' for me at normal listening levels (with too much bass).
I'm only using it when listening at very low levels. I suppose it was created for this purpose.

If you don't like that dac send it back and get something else, I doubt that playing with its volume control will change anything.

Do you have the su9 with the da9? what kind of sound do you have?
 

ceausuc

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Do you have the su9 with the da9? what kind of sound do you have?

I have the little brother: SA300 feed by Khadas Tone Board powering Q Audio Concept 20.
The sound is imho too good for the price I paid.
I sometimes prefer listening to this setup even if a have a technically much better headphone setup...
This is my subjective opinion, with different speakers, so you may see thing differently. Your flat sound could be my 'good' sound :)
But since you have another dac that you like I would suppose that this dac is just not for you. What options do you have? Keep it and start changing amps, speakers?
 

reddie.k

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Thank you!
I will try.
I have Elac dbr62

The Elac DBR-62 are very nice speakers. However they are difficult to drive due to impedance dips. To really make them sing you need a powerful amplifier.

"However, note the area I have circled. Impedance is high at about 8 ohms but the phase angle is quite acute at nearly 50 degrees. This means the speaker will ask for current when the output voltage is very low. So you better have a beefy amplifier to drive this speaker."

From the review here:https://www.audiosciencereview.com/...-debut-reference-dbr-62-speaker-review.12232/
 

ceausuc

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The Elac DBR-62 are very nice speakers. However they are difficult to drive due to impedance dips. To really make them sing you need a powerful amplifier.

"However, note the area I have circled. Impedance is high at about 8 ohms but the phase angle is quite acute at nearly 50 degrees. This means the speaker will ask for current when the output voltage is very low. So you better have a beefy amplifier to drive this speaker."

From the review here:https://www.audiosciencereview.com/...-debut-reference-dbr-62-speaker-review.12232/

Elacs are notoriously difficult loads and those Merus amps aren't really powerful, true.
But how do you explain the fact that a dac that outputs 2V (dragonfly) is more dynamic than the SU9 with gives 4V from its balanced out? This is a BIG difference and any amp will sound significantly 'louder' (dynamic?) with 2 more V on input.
 

mario_rouge

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Elacs are notoriously difficult loads and those Merus amps aren't really powerful, true.
But how do you explain the fact that a dac that outputs 2V (dragonfly) is more dynamic than the SU9 with gives 4V from its balanced out? This is a BIG difference and any amp will sound significantly 'louder' (dynamic?) with 2 more V on input.
Maybe is a faulty unit...
 

reddie.k

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Elacs are notoriously difficult loads and those Merus amps aren't really powerful, true.
But how do you explain the fact that a dac that outputs 2V (dragonfly) is more dynamic than the SU9 with gives 4V from its balanced out? This is a BIG difference and any amp will sound significantly 'louder' (dynamic?) with 2 more V on input.

I don't have the dragonfly nor the da9 so I can't really answer if indeed the dragonfly sounds louder than the su9 (which it probably shouldn't). Maybe the dragonfly distorts bass and that is why is perceived as louder. Maybe su9 is faulty. In my setup the SU-9 is excellent in sound quality and very loud, comparable to the NP-S2000 Yamaha network player which is a beast and three times the price.

I am choosing to go with the very high possibility (if not certainty) that this amp can't give the current needed to drive the elacs correctly. An amp is needed to have high power output and to go as close as possible to doubling the watt output of 8 ohms at 4 ohms. That means it has sufficient power to drive difficult speakers.

An example:https://www.audiophonics.fr/en/powe...reo-amplifier-ncore-2x250w-4-ohm-p-14185.html This one has 2x150W at 8 ohm and 2x250 at 4 ohms.
 

Sanlitun

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I've had mine for about two weeks now. A fair bit of experimenting with different amplifiers and settings has brought me back to where I had intended to be with the THX 789. My goal was to build a second system using all new and hyped components to stand as a counterpoint to my main system. A couple things I have found along the way:

The sound quality falls off markedly if variable volume is engaged. This is to be expected but I notice it more on this DAC save for any other DAC except the Mytek Brooklyn. It's not really important but matching your system to use the XLR outs without attenuation will improve quality.

It uses the +5 volts from the computer USB connection. Their measurements will say this doesn't matter but there are those who will have concern. I had assumed all recent XMOS DACs that are not USB powered would probably have the USB isolated.

Maybe a tiny bit of harshness/grain in the midrange. Hard to say where this is coming from yet.

All in all I am happy with the unit. There is not really much to be gained unless one is willing to spend a few times the money.
 

Shoaibexpert

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Hi guys, just wanted to check if the SU-9 S/Nos starting with 3200 (I am assuming this is the new lot for the SU-9s) have been checked/inspected by someone to have the 3rd harmonic issue corrected before leaving the factory? Maybe there is any communication with the manufacturer/retailers. Thanks
 
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muslhead

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FYI
Thats not what mine started with and ShenzhenAudio told me mine was fixed before they shipped it.
 

Shoaibexpert

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FYI
Thats not what mine started with and ShenzhenAudio told me mine was fixed before they shipped it.
Thanks. Has there been any reported HW changes in the new lot then? SMSL is notorious in doing that as you may already know! I guess I just dont get why the S/N sequence change...
 

Shoaibexpert

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The sound quality falls off markedly if variable volume is engaged. This is to be expected but I notice it more on this DAC
Hi Are you saying that the 'Pre-amp' mode on the SU-9 sounds better than the Var volume mode?

Which makes me wonder how do DACs attenuate signals while keeping the signal bit perfect....
 
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muslhead

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Thanks. Has there been any reported HW changes in the new lot then? SMSL is notorious in doing that as you may already know! I guess I just dont get why the S/N sequence change...
Sorry, dont know the answer to that question. But since its SMSL there may or not be and they may or may not tell anyone. :rolleyes:
 

reddie.k

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If it helps someone:

I connected the su9 via optical to a samsung tv and the sound was intermittent. I started increasing the PLL value and when it reached to 10 the problem stopped.
 

JSmith

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Wonder if the 3rd harmonic issue appears also over SPDIF connection or it's only a USB thing?
Input type is irrelevant in this case... it is simply when playing any stereo signal, one channel has high 3rd harmonic distortion.
I started increasing the PLL value
How, are you using debugging tools?



JSmith
 
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