DAC/Pre-amp for JBL 305m MKIIs

[Robbo99999]

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

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.

Well, maybe, try unplugging it! ha

 

[SK123]

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.

I have zero experience with soldering, or dealing with any electrical stuff

 

[SK123]

Ok so I unplugged the fridge.

I still hear no voice (or very little, barely noticeable hum) when running the CPU test, unlike the GPU that seems the culprit here.

 

[AnalogSteph]

I have zero experience with soldering, or dealing with any electrical stuff

Too bad, that would have been a near-free fix to try. Anything else you'd have to shell out at least 50 Canadian rubels for (whatever it is that a music store would charge you for 1x Behringer HD400, 2x RCA to 1/4" TS and 2x TRS to XLR cables). An RCA ground loop isolator may be a tad less but I have no idea whether you can get any decent ones (performance of these can be a bit lackluster). I know the HD400 is decent enough.

 

[gr-e]

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.

The issue with ground loops is that they act as an antenna and pick up all kinds of noises. The GPU does not cause a ground loop, it makes lots of noise that induces current in the loop.

Ok so I unplugged the fridge.

I still hear no voice (or very little, barely noticeable hum) when running the CPU test, unlike the GPU that seems the culprit here.

I fixed this issue with my 305s by using a power strip without a ground pin, not sure if it's a good advice haha

 

[Robbo99999]

Ok so I unplugged the fridge.

I still hear no voice (or very little, barely noticeable hum) when running the CPU test, unlike the GPU that seems the culprit here.

Did you try with unplugged fridge and GPU load at the same time whilst playing music? This might rule out some kind idea that fridge might be the source of the noise and then the GPU load is somehow magnifying that?? Might be worth a try.

 

[SK123]

Too bad, that would have been a near-free fix to try. Anything else you'd have to shell out at least 50 Canadian rubels for (whatever it is that a music store would charge you for 1x Behringer HD400, 2x RCA to 1/4" TS and 2x TRS to XLR cables). An RCA ground loop isolator may be a tad less but I have no idea whether you can get any decent ones (performance of these can be a bit lackluster). I know the HD400 is decent enough.

Ok thanks man. Yes, seems another purchase list but lets see..

 

[SK123]

Did you try with unplugged fridge and GPU load at the same time whilst playing music? This might rule out some kind idea that fridge might be the source of the noise and then the GPU load is somehow magnifying that?? Might be worth a try.

Yup I tried that, it still makes the same ole noise.

 

[AnalogSteph]

I fixed this issue with my 305s by using a power strip without a ground pin, not sure if it's a good advice haha

No, probably not - IEC Class I devices must generally be provided with PE to meet code. From the pictures seen here it looks like the JBLs may not be doing very much with PE to begin with (I would have expected some Y caps at least?), so as long it's just them and not the PC itself you'll probably be fine.

Ok thanks man. Yes, seems another purchase list but lets see..

I mean, you can always get the M2 or another interface instead and have some extra functionality. That's up to you.

 

[Robbo99999]

The issue with ground loops is that they act as an antenna and pick up all kinds of noises. The GPU does not cause a ground loop, it makes lots of noise that induces current in the loop.

Hmm, well maybe there's gaps in my understanding then, so maybe it is a ground loop, a lot of people still seem to think it is....I had thought that my little experiment was showing interference between components within the the PC rather than somehow magnifying an existing ground loop....especially as he can play music fine without any GPU load.

@SK123 , I might have been wrong in my conclusions from our little experiment, but I think either way if you do get another DAC it should be an external one, like USB DAC or something, because hopefully that won't be negatively influenced by the noise within your PC. As for ground loops, I don't know why you would be having them still if you have all your gear that is connected together only powered by one electrical outlet. I suppose a balanced DAC would give you another level of protection against ground loop concerns, but at this point I'm not totally convinced about ground loop in your case. I use the Topping E30 DAC which I would recommend as a non-gaming DAC, that's a USB DAC, but it's not a balanced DAC......it's possible you may just need to use an external USB DAC rather than a balanced DAC to solve your issues, because I'm not convinced you have ground loop issues, but like I said others think differently. I'm not sure how much more input I can give this thread, because that's all my thoughts encapsulated.

EDIT: or if it really is a ground loop you could try exploring fixing that issue with the help of people in this forum and then you can keep your existing DAC....instead of going down the route of balanced or un-balanced external USB DAC.

 

[SK123]

Agreed Steph and Rob. I can always return one product or another if it doesn't fix my problem. I really like the software aspect of my soundcard as it has hifi mode, as well as different dolby virtual speaker settings (which I love).

I dont know with an external DAC, I can still get a software that would provide me with dolby virtual speaker.

 

[Robbo99999]

@AnalogSteph , you edited your post after I quoted it (https://www.audiosciencereview.com/...-pre-amp-for-jbl-305m-mkiis.14819/post-463398), and given other people's reply here too I sense that you know what you're talking about and that you're probably right!

@SK123 , if you want virtual 7.1 surround sound for gaming then I think you have to use a gaming sound card unless some other people know of other options that would be compatible with games. I use SoundblasterX G6 (https://www.audiosciencereview.com/...w-and-measurements-of-sound-blasterx-g6.7016/ ), but it's buggy as hell so I really couldn't recommend it to you. It works fine and really well with my desktop, but all sorts of strange bugs when used with my laptop....the virtual 7.1 simulation in headphones is really great though.....that would be a risky purchase for you and it's not a balanced DAC, I'm unaware of any gaming balanced DACS, but I've not researched it. SoundblasterX AE5 which is a card that goes in your PC like your existing one (probably a bad idea given your experience!), has been reviewed here (https://www.audiosciencereview.com/...and-measurements-of-sound-blasterx-ae-5.9114/ ) and seems less buggy than SoundblasterX G6. I don't think you should go with either of those given your current issues & the buggy nature of the G6.....if you want to use virtual speakers in your headphones I'd stay with your current DAC and try to get the ground loop sorted out.

EDIT: you can use Dolby Atmos for headphones (https://developer.dolby.com/blog/dolby-atmos-for-headphones/ ) with any 2 channel DAC as a software solution or Windows Sonic (https://www.howtogeek.com/356481/how-windows-sonic-spatial-sound-works/ ). I've tried both and it didn't give me a proper sense of virtualised 3D positioning in games.....the only one I've tried that works is Soundblaster's cards that emulate 7.1 in headphones by using their proprietry hardware & software....Windows will see it as a 7.1 device too, whereas it didn't for me using Windows Sonic & Dolby Atmos.....so when it comes to virtualised speakers I can only recommend Soundblaster and all the problems that entails that we've talked about.....well also recommending your existing sound card as a solution once sorting ground loops still sounding like best plan.

 

[SK123]

Too bad, that would have been a near-free fix to try. Anything else you'd have to shell out at least 50 Canadian rubels for (whatever it is that a music store would charge you for 1x Behringer HD400, 2x RCA to 1/4" TS and 2x TRS to XLR cables). An RCA ground loop isolator may be a tad less but I have no idea whether you can get any decent ones (performance of these can be a bit lackluster). I know the HD400 is decent enough.

Hey Steph,

Could you kindly verify for me the connections. RCA to TS would connect the HD400 (input) to the soundcard, and TRS and XLR cables would connect monitors to the HD400 (output)? Thanks.

I also needed to know, if I compared Motu M2 DAC, to the one with Essence STX II soundcard, is the difference minimal, or could I improve the audio sound quality a good deal playing off M2 rather than the soundcard?

 

[AnalogSteph]

Could you kindly verify for me the connections. RCA to TS would connect the HD400 (input) to the soundcard, and TRS and XLR cables would connect monitors to the HD400 (output)? Thanks.

Si.

I also needed to know, if I compared Motu M2 DAC, to the one with Essence STX II soundcard, is the difference minimal, or could I improve the audio sound quality a good deal playing off M2 rather than the soundcard?

Both are capable of performance well in the "audibly transparent" zone, not to mention far exceeding the LSR305s. The STX arguably has the somewhat better DAC still, but without balanced I/O will struggle to get the performance "on the road". (Xonar cards with extra power connectors tend to be somewhat susceptible to internal ground loop issues as well.) The M2 does really well given its modest USB power budget.

Quite frankly, you've been able to buy soundcards and interfaces with "as good as you're ever going to need" DAC/ADC performance for about 15 years now - LynxTWO / L22, EMU 1212M and 0404 USB or Xonar D1 / D2, anyone? My bets on the top reasons for retirement in this class would be driver issues / support (let's just say I've wrestled with plenty of problematic cards over the years, from Terratec DMX to Xonar D1 and D2), interfaces going out of fashion (I have been looking for a modern motherboard with at least one PCI slot lately - can you say "slim pickings"?), and the odd defect.

 

[SK123]

Thanks for the info. I am happy to hear my soundcard would do better.
I ordered the following off Aliexpress: https://www.aliexpress.com/snapshot...erId=8017304674727592&productId=4000087053010

The Behringer HD400 for some reason is CAD $68 + $22 shipping at Amazon.ca, while I got the above for like $22. Just hope the performance is good. The cables oddly costed me like $40 at the amazon. Not that bad considering I dont have to continue to waste money on more upgrades.

 

[AnalogSteph]

If you're not sure whether your clone HD400 is up to par with the real deal, I could certainly crack mine open and take some pictures. The scale says 184 g for this 2014 specimen, still in silver at the time. Not sure why that would be so expensive in Canada - have you tried an actual music store? They're 23.40€ at Thomann over here, and not even available on Amazon at this point. Yep, found something, $31.59 CAD at L.A. Music. As convenient as marketplaces can be, sometimes you can't beat a specialized retailer.

 

[SK123]

lol Thanks man. Cant believe you went extra mile and checked my local prices. These people are charging $25 shipping charges ($60 in total incl tax) and their pick-up location is around 3+ hrs one way drive. The clone costs me around $23 shipped. Their are positive reviews with other sellers for the same product, so lets see.

 

[SK123]

Hi guys,
Just wanted to update, received my clone HD400 today, and all the hum and buzz (including games) is completely dead. And I cant thank all you guys enough for your suggestions and help with this.

But I do feel that wiring though the HD400, the richness of the speakers is quite reduced, and they sort of sound like when I got them first (like the burn-in time required). Also, the overall volume is reduced to like 1/4th which is not a big deal, but I do hope my speakers will back again begin to sound how they were sounding before wiring this product, hopefully within couple of hrs of playing.

Also, I dont know if this is normal with jbl 305s, but I can't hear footsteps of players or even myself in BF5 unless I crank up the volume super high (too high to enjoy the game/audio).

 

[Robbo99999]

Burn in with speakers isn't really a thing, it's a myth. I don't know enough about how the HD400 works to describe if it will reduce sound quality or not. The loss of volume is a bit disturbing, on the surface, but I don't know if that is expected or not.

 

[ng411s4]

I admit to not having read every post in this thread, but, just in case it may help:
What have you set the input sensitivity switch to on the 305p? For balanced inputs, it should be at +4dBu, but for single ended input (i.e. RCA to XLR) it should be at -10dBV.
If it is set incorrectly, (+4dBu with a single ended source) the output volume will very likely be lower than expected. Changing to the -10dBV setting might be a very straightforward fix for the "low volume" issue.