O2/Dac and Noise

[BoredErica]

A friend claims to be able to hear noise on my Mayflower o2/dac with volume knob at 30% and windows audio at 100% with a HD800. Do you think this is possible or is he BSing me? If he is able to hear noise at 30% volume, that's more than significant enough for him to hear the noise constantly when he's not playing audio on the computer. If this is true, would that be Mayflower's fault on the assembly, or NWavguy's O2 just not cutting it? BTW, he is not hitting the gain switch. Personally I hear none unless I hit the gain switch and up the volume knob to like 40, 50% and the sound of my fridge nearby is louder than whatever noise is present...

 

I told him to bring his earphones next time, and we'll do some blind tests on noise with both the Razer Moray he has and the HD800. His opinions on audio and claims about audio have been erm... questionable. So there's a decent chance he's BSing me, whether on purpose on accident.

[SSL]

The O2/ODAC is effectively silent when implemented properly. So...deduce.

[Cheesebaron]

Makes no sense as the HD800 are high impedance, compared to the output impedance on the O2, which is very low, this should mean the damping factor is very high and there should be no issues with hiss or anything like that.

 

Maybe he doesn't have the DAC and it is plugged directly into the computer he can hear noise from the PC. It is not uncommon to hear some high pitch noise, I.e. when moving the mouse, or when a HDD is reading or writing, especially from the front IO if it is not shielded well. If he is using front IO, using the connector on the back can in many cases help, otherwise if the noise persists he just has a rubbish sound card.

 

If you go with the O2/ODAC combo, you will not run into this issue.

[BoredErica]

Makes no sense as the HD800 are high impedance, compared to the output impedance on the O2, which is very low, this should mean the damping factor is very high and there should be no issues with hiss or anything like that.

 

Maybe he doesn't have the DAC and it is plugged directly into the computer he can hear noise from the PC. It is not uncommon to hear some high pitch noise, I.e. when moving the mouse, or when a HDD is reading or writing, especially from the front IO if it is not shielded well. If he is using front IO, using the connector on the back can in many cases help, otherwise if the noise persists he just has a rubbish sound card.

 

If you go with the O2/ODAC combo, you will not run into this issue.

No. The HD800s and O2/dac he is testing are mine. He's using my setup and saying he hears noise. My setup is definately an O2/dac combo, not just the amp and I am not using onboard audio. I think I'll know for sure whether he's BSing me once we start the blind test.

i dun hear deh noize tho.  :rolleyes:

 

Hard to imagine a guy with superhuman hearing is using Razer Morays on a 2005 sound card.  :unsure:

[Cheesebaron]

Sorry I just woke up when I wrote the above. With DAC in the second paragraph I obviously meant O2, but that doesn't change the fact that he was indeed using the ODAC.

 

There could be some noise on the USB connection, which interferes with the circuitry in the ODAC. Not sure how the ODAC filters that out. Get a third person to listen. If you don't hear it, then don't worry about it

[NannerBeans]

My o2/odac is silent no matter how loud I turn it so...

[BoredErica]

My o2/odac is silent no matter how loud I turn it so...

Even with gain switch toggled?

[NannerBeans]

Even with gain switch toggled?

Yeah I use it with the gain switch. 

 

I usually have it around 40-45% with the gain switch on but my windows volume is only at 50%

[BoredErica]

Yeah I use it with the gain switch. 

 

I usually have it around 40-45% with the gain switch on but my windows volume is only at 50%

Can you try: Max audio in Windows, gain switch on, and knob to max? I think I start to hear a hiss myself once knob is past 50% in this case.

Is it also possible, that the physical location of the Odac will affect hissing? If I have some major electronics next to the thing.

[NannerBeans]

Can you try: Max audio in Windows, gain switch on, and knob to max? I think I start to hear a hiss myself once knob is past 50% in this case.

Is it also possible, that the physical location of the Odac will affect hissing? If I have some major electronics next to the thing.

I'm on vacation and don't have it with me. And 50% on the o2 and 100% in windows is super loud. I don't have anything that is hard enough to drive to go anywhere near that. 

[BoredErica]

I'm on vacation and don't have it with me. And 50% on the o2 and 100% in windows is super loud. I don't have anything that is hard enough to drive to go anywhere near that. 

Yeah, that is loud. But that's where I can really notice the hiss. Short of both gain switch + volume up, I can't hear a hiss.

I'd say HE-6 would require that cranking of the volume, but at the same time it's probably not a good idea to match that with O2 anyways, so I can't really think of a case where I'd actually want to press the gain button no matter what headphone I have.  :blink:

[MayflowerElectronics]

You shouldn't hear noise no matter what the gain switch/volume is at.

 

Every situation is different, but it could be a bad USB cable or in-efficent shielding if he's using the front panel USB connections. Try a new USB cable and plugging the USB into the motherboard directly. Unfortunatly monoprices USB cables can be a bit crap some times.

[MayflowerElectronics]

Can you try: Max audio in Windows, gain switch on, and knob to max? I think I start to hear a hiss myself once knob is past 50% in this case.

Is it also possible, that the physical location of the Odac will affect hissing? If I have some major electronics next to the thing.

 

Also yes, if you have a cellphone or similar device sitting right on top of it you will pick up noise. (Sorry for double post didn't see this post).

 

Audio equipment shouldn't be very close to anything that gives off electrical noise (like a router).

[BoredErica]

You shouldn't hear noise no matter what the gain switch/volume is at.

 

Every situation is different, but it could be a bad USB cable or in-efficent shielding if he's using the front panel USB connections. Try a new USB cable and plugging the USB into the motherboard directly. Unfortunatly monoprices USB cables can be a bit crap some times.

The USB cable is plugged straight to the back of the computer on the back IO. USB 2? cable in a USB 3 slot for my MSI z87 G45. The Objective combo is sitting under my Catleap monitor, 3-4 inches away from my keyboard, 6 inches from speakers on both sides. (If that matters at all.) Guess the question asked here in a roundabout way is, is the location the amp/dac located physically important? Like say, I decide to put it directly on my computer case, or next to some other piece of electronic, etc.

 

Never thought I'd be asking this question, but what would be a "good" USB cable?

 

EDIT:

Your second post now just showed up - So maybe the Objective shouldn't be located right under the monitor? How far away do you reckon it should be from it or my speaker?

There is a modem for the internet for the entire house located 2-3 feet away.

[MayflowerElectronics]

The USB cable is plugged straight to the back of the computer on the back IO. USB 2? cable in a USB 3 slot for my MSI z87 G45. The Objective combo is sitting under my Catleap monitor, 3-4 inches away from my keyboard, 6 inches from speakers on both sides. (If that matters at all.) Guess the question asked here in a roundabout way is, is the location the amp/dac located physically important? Like say, I decide to put it directly on my computer case, or next to some other piece of electronic, etc.

 

Never thought I'd be asking this question, but what would be a "good" USB cable?

 

Ah okay, it sounded like you had the thing sitting next to a router or something. No those devices don't give off any strong interference but just to be safe move the O2 away from the monitor and see if that does anything as some monitors *that I can recall* can give off noise.

 

No such thing as a good USB cable, just one that works. It's a standard mini-B design so they're pretty common if you can find one to switch it out with. If you are still hearing noise you can send in the amp and I'll see if I can hear any noise and I'll most likley swap out the ODAC since that's the only thing that can introduce noise into the circuit.

[BoredErica]

Ah okay, it sounded like you had the thing sitting next to a router or something. No those devices don't give off any strong interference but just to be safe move the O2 away from the monitor and see if that does anything as some monitors *that I can recall* can give off noise.

 

No such thing as a good USB cable, just one that works. It's a standard mini-B design so they're pretty common if you can find one to switch it out with. If you are still hearing noise you can send in the amp and I'll see if I can hear any noise and I'll most likley swap out the ODAC since that's the only thing that can introduce noise into the circuit.

They say a picture is worth a thousand words - Probably not in this case but here are some picts:

Here is my normal setup:

 

Here is me trying to test the noise:

 

The PC case is covered by a blanket and a sleeping bag in attempts to prevent the sound of the fans of the computer from interfering with the test.

The volume knob has 7 dashes around it. 

 

When gain switch is hit, volume knob at the third dash and up, I can hear hiss. At max volume with gain switch on, the hiss is loud enough to distract a normal user.

When the gain switch is NOT hit, volume knob at 5th dash and up, I can hear hiss. I can now hear hissing without gain switch because I've covered up the PC with stuff and the fridge is being dead silent right now.

 

Funnily enough: when the USB cable is removed from the Odac/O2 and the gain switch is toggled on, the hissing is replaced by a buzzing sound. And when I put the USB cable back in, the buzz stops and is replaced by the normal hiss again.

The headphone used to test is the HD800. The cable/power cables are the ones that shipped with the Objective.

[MayflowerElectronics]

They say a picture is worth a thousand words - Probably not in this case but here are some picts:

Here is my normal setup:

 

Here is me trying to test the noise:

 

The PC case is covered by a blanket and a sleeping bag in attempts to prevent the sound of the fans of the computer from interfering with the test.

The volume knob has 7 dashes around it. 

 

When gain switch is hit, volume knob at the third dash and up, I can hear hiss. At max volume with gain switch on, the hiss is loud enough to distract a normal user.

When the gain switch is NOT hit, volume knob at 5th dash and up, I can hear hiss. I can now hear hissing without gain switch because I've covered up the PC with stuff and the fridge is being dead silent right now.

 

Funnily enough: when the USB cable is removed from the Odac/O2 and the gain switch is toggled on, the hissing is replaced by a buzzing sound. And when I put the USB cable back in, the buzz stops and is replaced by the normal hiss again.

The headphone used to test is the HD800. The cable/power cables are the ones that shipped with the Objective.

 

Doesn't seem right. Shoot us an email on our website so I can get you an RMA number. Also blankets won't stop electrical noise

[BoredErica]

 

Doesn't seem right. Shoot us an email on our website so I can get you an RMA number. Also blankets won't stop electrical noise 

 

The blanket is to prevent the noise of the fans. By noise I mean the sound of the fans spinning, not electrical noise. They are pretty loud, louder than the noise when gain is not toggled. I ought to replace them with Noctua fans one day. It's harder to hear quiet hissing when the fans are blaring at my ears. 

 

 

I just rewrote the situation on another forum while chatting about audio, so I'll copy and paste that here as that is far more intelligible than the mess I wrote here.

 

 

 

In a mostly unrelated note:

I just had a real trip with my Objective. This just happened.

 

Well ok. So my friend was the one complaining about hissing on my Objective. Hissing? Objective? If there's anything the Objective can do, making hissing inaudible ought to be it... He insists he can hear hissing with gain off and knob at 30% (Windows volume @ 100%). He went on to talk about how it's not placebo, he's as confident of it as his eyesight (wut?) and proceeds to tell me he can see leaves on a tree 7 miles away from him. (Again, wut?)

 

But I didn't want to dismiss his claim immediately so I did some testing. The problem is that my room is not dead quiet... far from it, with my PC's case fans being pretty loud. So, I put a blanket and then an entire sleeping bag, covering the entire case and significantly slashing the ambient noise of the room. If I want to hear quiet hissing I better make the room quiet. I noticed hissing with gain on and volume at max (something I already knew, not news). But more importantly:

A) Hissing with gain on start to be audible at the 3rd dash.

B) Hissing without gain start to be audible at the 5th dash. (For this test as I said, the computer is silenced by my blanket and sleeping bag. This is assuming my fridge is being dead silent and my PC is quieter than it actually will be in normal operation and nothing is playing on my computer. Realistically speaking, running HD800s on O2 at  A or B won't happen because it is so LOUD, my ears will burst. Same for my Rokits. So in reality: Even if the hissing is present and my fridge is dead silent, and my computer is silenced by two layers of warm coverings AND the computer is not playing anything, I STILL cannot hear hissing because there is no reason for the volume knob to be up that high.)
(What dash? There are dashs next to volume knob. Here is a picture)

But I was told by both Tyler from Mayflower and NWavguy's blog post that it ought to be silent... even at max... with gain on. So I did some more digging.

 

I was thinking maybe it's where the USB cable is plugged in. Nope, back IO port. Switching to front port did nothing. Changing USB cables did nothing. Using another wall outlet did nothing. Moving the Objective physically away from my monitor did nothing. I took the Objective and headphone upstairs to my netbook. It's a puny 2008 Atom netbook. This is where the oddity begins:

 

C) There is NO HISSING normally.

D) If I play a midi track on Windows Media Player and pause it to turn knob to max and gain on, I can hear a hiss. If I close Windows Media Player or I let the midi track finish and then I turn the knob to max and gain on, there is NO HISS. And this weirdness does not occur around MP3 (there were 3 sample tracks that came with Windows), neither did it occur with a wav clip I found on the netbook. I double checked, triple checked this because it makes no sense to me. I had the midi track paused, I hear hissing. I click "close" on the media player, and hissing disappears.

On the other hand, for the desktop, no matter what I was or wasn't playing, the hissing is audible with gain on and knob to max.

 

E) Later I found that going to Control Panel -> Audio Hardware -> Odac Properties -> Advanced and I changed the output mode from 16bit 44khz to 24bit 96khz, the hissing stops. This applies to both the netbook and the desktop. I can hear the hiss become less audible when I change from 16bit 44khz mode to 16bit 96khz mode.

 

Mind = Blown.

I don't understand why this happens.

But I am as certain as I can be in my sleep-deprived, mentally-compromised state that this is the fix.

[MayflowerElectronics]

Still shouldn't matter what bit rate and frequency it's set at you shouldn't normally hear noise, but as default I always set it to max bit/frequency.

[BoredErica]

Still shouldn't matter what bit rate and frequency it's set at you shouldn't normally hear noise, but as default I always set it to max bit/frequency.

That's what I was thinking too. The way the hissing manifests and the conditions for it to manifest on my desktop vs my netbook also completely confuses me. But I'm doing it over and over again: 16bit 44khz, hiss. 24bit, 96khz, no hiss. Don't understand why, it just is.  :blink: Am I dreaming?

 

If you refresh the page, I updated the post right above yours with a more coherent info. There I state that there is no reason even @ 44khz 16bit for me to ever hear the hiss because that assumes the PC is covered with blankets, the fridge is silent, nothing is playing on the computer, and the volume is up higher than I ever have it at. 3rd dash w/ gain is ouch, but 5th dash without gain is RIDICULOUSLY LOUD. But none of that matters now I guess, because playback is at 24bit 96khz. I suppose in theory a playback mode that is lower than that of the track will diminish quality - but I doubt in any way that is audible.

 

I'm thinking of not sending in the Objective for RMA. It's a hassle, it's gone with 24bit playback mode somehow, even at 16bit with hiss, I will never hear it under normal operation. Why bother both of us with something that's not really an issue, right?

[BoredErica]

If anybody would like to do a quick test... Set Objective volume knob to max, gain switch toggled on, Windows volume max, playback mode 16bit 44khz, tell me if you hear hiss. You probably won't, but always curious.