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DAC/Pre-amp for JBL 305m MKIIs

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SK123

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Measurements:
  1. Grace SDAC Balanced
  2. SMSL SU-8 (v2)
  3. SONCOZ LA-QXD1
I don't think you're going to have issues with any of these DACs from a transparency perspective. You might want to take a look at features, build quality, warranty, aesthetics, return policy, etc. and determine which is best suited for your situation.

Hi Rick,
Thanks for the above links. Now, M2 and Grace SDAC price difference is negligible for me in CDN. Between M2 and Grace SDAC, which one should I go for, given somebody rated Motu M2 above SMSL SU-8.
 

Robbo99999

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Hi guys,

Could you please recommend DAC/Pre-amps for the above said active speakers and in the appropriate price range? I prefer if it doesn't have an amp (unless all DACs have built in headphone amps). It's important they provide balanced connection for the monitors.

Once I have the means, I'll go for the more expensive stuff including speakers, headphones etc, so would go for more higher end amps and DACs then. Thanks!!

Also, any links to previous discussions relating to my inquiry would be great as well.
I read your posts, I think your current soundcard should be fine with those speakers. Your soundcard has RCA outputs that are not part of the headphone amp, so you don't have to worry about that, those RCA connections are designed for speakers, the headphone amp is just related to the 6.3mm port which is described as "Amplified 6.3mm headphone output" in the manual here....that's my understanding from scanning the manual: https://dlcdnets.asus.com/pub/ASUS/Audio_Card/Essence_STX_II/u12055_essence_stx_7_1_qsg_v3_print.pdf

So I think your soundcard should work fine with your JBL speakers. The hum you talk about, is that only when playing games or is that when listening to music too? (I'm trying to rule out a software or ground loop issue). If it's a ground loop issue then you can just make sure that everything is run off the same one power outlet (plug in the wall) - so for example you'd make sure your PC/monitor/printer/JBL speakers were all getting power from the same power outlet. Apparently using a balanced DAC with balanced cables can get rid of this problem too, but why buy another DAC if your current DAC can be fixed. I had the same problem with my JBL 308 speakers, the hum, it was being caused by a TV aerial (that is connected to my TV and my speakers are connected to the TV) and also by not running all the connected equipment off the same outlet....by me getting a ground loop isolator for the aerial (https://smile.amazon.co.uk/gp/product/B002MQET2A/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1 ), and running everything off the same outlet fixed the hum. They were two seperate hums, the aerial was causing the most obvious hum, and the ground loop from not running everything off the same outlet was causing a more subtle hum that only came about north of dial 5 on the volume control on the back of the speakers.
 
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TimW

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I read on this forum that Motu 2 performed better than SMSL SU8 and thats the only thing tempting me toward it.
https://www.audiosciencereview.com/...faces-headphone-amp-and-dac.13489/post-406905

That, and may be the volume control. I dont own any guitars etc yet so no recording at the moment.

It's mostly the DAC and balanced connections I'm interested in, and if M2 DAC is as good as the DACs mentioned above than will definitely go with the M2 since for the price range it's offering more.
All of the DAC's listed so far, including the Motu, should sound identical. Choosing audio electronics based on someone's sighted listening impressions is a great way to constantly waste your money on "upgrades."

Just pick which DAC based on features. If you want a volume knob and analog inputs then pick the Motu. The SDAC has a clean look and SPDIF inputs. The SU8 has SPDIF inputs, an internal power supply, a remote control, and "sound color settings."
 

RickSanchez

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Hi Rick,
Thanks for the above links. Now, M2 and Grace SDAC price difference is negligible for me in CDN. Between M2 and Grace SDAC, which one should I go for, given somebody rated Motu M2 above SMSL SU-8.

Well, I wouldn't take my word for anything as I'm just a random guy on the internet. But personally I would not buy the Motu M2 because it hasn't been measured on ASR yet. (The 624 looks OK but that does not mean the M2 is a good product.) That's a risk I'm not willing to take given that there are so many reasonably-priced DACs (with XLR outs) that have been measured on ASR.

So if you forced me to pick between those two I would opt for the Grace SDAC (Balanced) -- I'm assuming that's what you mean, not the Grace SDAC which only has RCA outputs -- because it measures fine to the point where it's audibly transparent.
 

AnalogSteph

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Now, M2 and Grace SDAC price difference is negligible for me in CDN. Between M2 and Grace SDAC, which one should I go for, given somebody rated Motu M2 above SMSL SU-8.
Should be pretty much a wash, performance wise. The measurements for the M2 I've seen so far (e.g. by Julian Krause) have been nothing short of very good to excellent in all respects, just QC has apparently been a problem for a few people. If you see any use for its (also very good) mic inputs at all (there are plenty of good sub-$100 condenser mics these days, some around $50 even, there's almost no reason not to have one), I would strongly consider the M2.
 
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Thank you so much guys for your continuous support.

Rob: There's little hum/distortion noise (which is not greatly bothersome and I don't really mind) and I dont even hear it when music is playing, but I just cannot launch/play any game. Its a huge BUZZ/ZINGG.. that's continuously there until you exit the game, and I have tried it on several games, and everytime it was the same issue. All my computer connections are from the same outlet as well.

Feels like it's some electronics inside of the PC causing this, or the soundcard itself. I really enjoy listening music through it, just dont understand why cant launch games without being blasted by that BUZZZZ sound.

Rick - Yes I meant the balanced version. Price wise Im stuck between M2 and Grace, but leaning more toward the M2 because all the extra features it provides.

Steph: Yes I am leaning toward it too, given it's as good a DAC as the Grace bal, and both nearly the same price in CDN.
 
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All of the DAC's listed so far, including the Motu, should sound identical. Choosing audio electronics based on someone's sighted listening impressions is a great way to constantly waste your money on "upgrades."

Just pick which DAC based on features. If you want a volume knob and analog inputs then pick the Motu. The SDAC has a clean look and SPDIF inputs. The SU8 has SPDIF inputs, an internal power supply, a remote control, and "sound color settings."

The SU 8 is about ~$100 more for me in CDN. The remote feature is good but not that important. The sound color setting, dont knwo if it would help me with the monitors.

Also very well said about constantly wasting money on "upgrades" :/. Considering I have a really tight budget, and cant continuously upgrade my gadgets, hopefully will get the ideal product out of all this discussion.
 

Robbo99999

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Thank you so much guys for your continuous support.

Rob: There's little hum/distortion noise (which is not greatly bothersome and I don't really mind) and I dont even hear it when music is playing, but I just cannot launch/play any game. Its a huge BUZZ/ZINGG.. that's continuously there until you exit the game, and I have tried it on several games, and everytime it was the same issue. All my computer connections are from the same outlet as well.

Feels like it's some electronics inside of the PC causing this, or the soundcard itself. I really enjoy listening music through it, just dont understand why cant launch games without being blasted by that BUZZZZ sound.
Ok, cool, sounds like it's mainly an issue associated with gaming. Another poster here I read they mentioned the graphics card as a potential reason for the hum/buzz....I've thought of a way you can test this that should isolate whether it's a hardware (associated with GPU) or software driver issue. My theory is that you need to try to run the GPU at 100% load but not in a game, and then you'll come out of whatever is creating your 100% GPU load (and leave that running in the background), then you'd fire up some music in ITunes or whatever player you use and then you'd see if your music plays without a hum/buzz.....this test will isolate if it's just the high GPU load that is causing the issue or not. If it passes this test without hum/buzz then it's probably a driver/software issue. In terms of what to use to create the GPU load start off with the GPUz render test:
Click here where you can see my mouse pointer:
GPUz Render Test.jpg

Then you can open up the Sensors Tab to check your graphics card is under a little stress:
GPUz Render Test (sensors).jpg


Now this is quite an easy test for the GPU so you might need to run a different GPU test that uses more Watts. If GPUz Render Test above doesn't create the buzzing sound you're talking about (as you're listening to music whilst running the GPUz Render Test at the same time), then use a GPU stress test that is harder on the GPU: try running Unigine Heaven benchmark on a loop but as a window (window mode not fullscreen), and make sure you turn off the sound effects in Unigine Heaven benchmark (think that's an option) so that you can make sure the GPU loading program is not asking your soundcard to produce any sound......then listen to music whilst that's running & see if you still get the buzzing sound. If you don't get the buzzing sound then it's some kind of software driver type issue rather than the hardware of your loaded GPU causing interference.
 
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Ok, cool, sounds like it's mainly an issue associated with gaming. Another poster here I read they mentioned the graphics card as a potential reason for the hum/buzz....I've thought of a way you can test this that should isolate whether it's a hardware (associated with GPU) or software driver issue. My theory is that you need to try to run the GPU at 100% load but not in a game, and then you'll come out of whatever is creating your 100% GPU load (and leave that running in the background), then you'd fire up some music in ITunes or whatever player you use and then you'd see if your music plays without a hum/buzz.....this test will isolate if it's just the high GPU load that is causing the issue or not. If it passes this test without hum/buzz then it's probably a driver/software issue. In terms of what to use to create the GPU load start off with the GPUz render test:
Click here where you can see my mouse pointer:
View attachment 74655
Then you can open up the Sensors Tab to check your graphics card is under a little stress:
View attachment 74656

Now this is quite an easy test for the GPU so you might need to run a different GPU test that uses more Watts. If GPUz Render Test above doesn't create the buzzing sound you're talking about (as you're listening to music whilst running the GPUz Render Test at the same time), then use a GPU stress test that is harder on the GPU: try running Unigine Heaven benchmark on a loop but as a window (window mode not fullscreen), and make sure you turn off the sound effects in Unigine Heaven benchmark (think that's an option) so that you can make sure the GPU loading program is not asking your soundcard to produce any sound......then listen to music whilst that's running & see if you still get the buzzing sound. If you don't get the buzzing sound then it's some kind of software driver type issue rather than the hardware of your loaded GPU causing interference.

Hi Rob,

Yes the noise started up right away as I ran the basic render test from the pic above. The noise was not as loud as running the actual game, but it was still strange loud noise. I played the music and their still was the buzz sound in the background.

I forgot to mention above that even when I move my pointer/mouse generally, it still creates light sound/buzz in my speakers.

Anyway I truly love Dolby Virtual Speaker feature with 8 channels and the 'music' button toggled on my soundcard. I hope theirs a fix to this without me getting additional DAC.
 
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Robbo99999

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Hi Rob,

Yes the noise started up right away as I ran the basic render test from the pic above. The noise was not as loud as running the actual game, but it was still strange loud noise. I played the music and their still was the buzz sound in the background.

I forgot to mention above that even when I move my pointer/mouse generally, it still creates light sound/buzz in my speakers.

Anyway I truly love Dolby Virtual Speaker feature with 8 channels and the 'music' button toggled on my soundcard. I hope theirs a fix to this without me getting additional DAC.
Right, ok, that's great in terms of diagnosing the problem. Because it's something to do with GPU load creating some kind of interference with your sound card rather than a software/driver issue. What CPU & GPU do you have and what power supply do you have in your PC (your PSU)? You could do the same test that you ran with GPUz, but this time run a CPU stress test whilst playing the music and then see if you still get the buzz/hum....this way we can narrow it down to is it just general high load in your PC causing the hum/buzz or is it the GPU specifically. You could run prime95 selecting it to run on half your total number of CPU cores (so the CPU doesn't get too hot), and then play music and see if you still have the same problem.

EDIT: didn't see your comment about the mouse pointer/mouse movement causing low level buzz too, strange because that doesn't load the PC up with Watts....it feels like there's some kind of weird interconnected hardware issues within your PC causing this interference. I'm a bit lost as to the cause of that particular point......but it would be interesting to see if you have the problem I mentioned in my previous paragraph re CPU test.
 
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AnalogSteph

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Yes the noise started up right away as I ran the basic render test from the pic above. The noise was not as loud as running the actual game, but it was still strange loud noise.

I forgot to mention above that even when I move my pointer/mouse generally, it still creates light sound/buzz in my speakers.
100% ground loop.

There are cheaper ways of fixing one (I am using a Behringer HD400 in a similar scenario - 1x 3.5 mm to 2x TS in, 1x TRS to XLR out), but getting a basically endgame level USB audio interface out of it has its perks, too. (You would not have to replace that unless either it fails or driver support is no longer cutting it at some point in the future.)
 

Robbo99999

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100% ground loop.
Definitely not a ground loop, that was a large part of the reason for that experiment...... he plays music fine from his PC through the speakers, but as soon as the GPU is loaded it creates the buzz/hum. It's a hardware issue of some sort in his PC causing interference between the components.

(He also has everything running that's connected off one outlet so I think that rules out ground loop)
 

AnalogSteph

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He's using RCA to XLR cables - I know of exactly one model of premade ones that are wired to actually take advantage of a balanced input, and they cost like 300 bucks, not 26.99 CDN. His chance of seeing ground loop issues is just about 100%, and the symptoms described are extremely typical. The power supply mains currents (reflecting PC usage) are capacitively coupled into the PE conductor, causing a signal voltage to be generated between PC ground and speaker ground, as both are tied to their respective PEs. Hence why there's quite the racket when loading the GPU (a 1070 is a nominal 150 W card).

There may be a chance of salvaging the cables if the back of the XLRs can be unscrewed and OP is sufficiently handy with a soldering iron. Signal ground is now presumably connected to both pins 1 and 3; it would have to be removed from pin 1 so that it only goes to 3 any more. That should result in 30-40 dB of usable CMRR at least.

People have reported differences related to motherboard quality (more upmarket boards with more PCB layers are likely to have lower ground return resistance etc.), but let's address the elephant in the room first.
 
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Robbo99999

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He's using RCA to XLR cables - I know of exactly one model of premade that are wired to actually take advantage of a balanced input, and they cost like 300 bucks, not 26.99 CDN. His chance of seeing ground loop issues is just about 100%, and the symptoms described are extremely typical. The power supply mains currents (reflecting PC usage) are capacitively coupled into the PE conductor, causing a signal voltage to be generated between PC ground and speaker ground.

There may be a chance of salvaging the cables if the back of the XLRs can be unscrewed and OP is sufficiently handy with a soldering iron. Signal ground is now presumably connected to both pins 1 and 3; it would have to be removed from pin 1 so that it only goes to 3 any more.
I fail to see how increased GPU load will suddenly cause a ground loop issue when he can play music through his PC to his heart's content with no symptoms, so far it's only when his GPU is loaded.....I fail to see how this can be a ground loop unless I'm missing some points in my understanding of how it's all fitting together. By the way I didn't understand your last sentence of your 1st paragraph, if that's the potential hole in my understanding of how GPU load can effect ground loops. (I'm suspecting instead that you didn't understand my experiment and are instead just describing what a ground loop is, which you can take from wiki or something).
 

gr-e

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Definitely not a ground loop, that was a large part of the reason for that experiment...... he plays music fine from his PC through the speakers, but as soon as the GPU is loaded it creates the buzz/hum. It's a hardware issue of some sort in his PC causing interference between the components.

(He also has everything running that's connected off one outlet so I think that rules out ground loop)
I don't think there are any issues with his PC. The ground loop picking up GPU interference, it's a very common situation. And the mouse movement is usually audible too for some reason, idk why :)
 
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Right, ok, that's great in terms of diagnosing the problem. Because it's something to do with GPU load creating some kind of interference with your sound card rather than a software/driver issue. What CPU & GPU do you have and what power supply do you have in your PC (your PSU)? You could do the same test that you ran with GPUz, but this time run a CPU stress test whilst playing the music and then see if you still get the buzz/hum....this way we can narrow it down to is it just general high load in your PC causing the hum/buzz or is it the GPU specifically. You could run prime95 selecting it to run on half your total number of CPU cores (so the CPU doesn't get too hot), and then play music and see if you still have the same problem.

EDIT: didn't see your comment about the mouse pointer/mouse movement causing low level buzz too, strange because that doesn't load the PC up with Watts....it feels like there's some kind of weird interconnected hardware issues within your PC causing this interference. I'm a bit lost as to the cause of that particular point......but it would be interesting to see if you have the problem I mentioned in my previous paragraph re CPU test.
So I ran the CPU test on two cores and their was no buzz this time.

I have i5-6500, Asus 1070 ROG, PSU 650w 80+ Gold
 

Robbo99999

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I don't think there are any issues with his PC. The ground loop picking up GPU interference, it's a very common situation. And the mouse movement is usually audible too for some reason, idk why :)
I don't know what a "ground loop picking up GPU interference" actually is, that sounds kinda vague. I still don't understand how high GPU load can cause or magnify a ground loop issue? To me it seems like my little experiment is instead showing somekind of interference coming from within his PC rather than one that is coming from outside of it.
 
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lol I didn't mention their is a mini fridge also connected to the same extension cord as my PC, may be that's causing extra buzz :facepalm:

the mouse noise is barely audible so that's not a big deal, it's just trying to run any games with normal audio is my concern.
 

Robbo99999

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So I ran the CPU test on two cores and their was no buzz this time.

I have i5-6500, Asus 1070 ROG, PSU 650w 80+ Gold
Could you try it again with all cores loaded up this time? Perhaps that wasn't enough load as it's only a 65W CPU. This is really just to see if the problem is coming from your GPU or if your PC is under general high load. But first, check that your CPU is not getting too hot when running Prime95 on all cores, because I don't want you to start thermal tripping/throttling your CPU.
 
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