Newbie with noise issue

lacogada

New member
Another newbie with noise issue.

Roland FP7 keyboard.
Behringer 802 mixer.
Behringer UCA 222 usb interface.
Desktop Win 7 with Reaper.

Two 1/4" balanced ( ? two black rings ) from keyboard line outs to mixer line ins.
Keyboard volume at 1/4.
Mixer channel volume at 1/2.

RCA jack from mixer output to UCA 222 inputs.

UCA 222 to computer by usb.

Mixer main volume at 0, no noise.
Noise gets louder as mixer volume is turned up.

Recording attached ... volume at zero then turned up and back down.
 

Attachments

  • Mixer_UCA222_Noise.mp3
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Sounds like the EFI I hear in my car when using the Aux in!

It might not make a difference, but I'd guess the keyboard out is not balanced, so you're carrying an open line from the keyboard into the mixer, which is assuming it's getting a balanced signal. The first thing I'd try is an unbalanced (TS-TS) instrument/patch cable. Just use the MONO/L out if you don't have a pair of them.

You have any old light dimmers in the room circuit, CFL bulbs on the desk, etc? This could be coming in via a power supply as well, though there's folks here that really understand the little bumping around electrons do and might say what it is right away... I'm a guesser :)
 
Tried two unbalanced patch cables but made no difference.

I found an adapter that let me hook the RCA cables from UCA 22 to keyboard line out L/mono,
completely by passing the mixer, and that is quieter.
 
Good keyboard, crappy mixer .... Why are you even using the mixer in this chain?
Fair question, but he took the mixer out and the noise was less. My question to [MENTION=125767]lacogada[/MENTION] is whether the remaining noise is the same kind or different? If it's the same kind, I'd suspect it's in the AC/mains, so start looking at dimmers, lighting, other devices on the circuit. Try a battery driving keyboard, or isolated power supply, or recording device instead of PC, etc., and try to isolate where the noise is coming in.

Edit: P.S. That Behri is probably not the best A/D device you could use for this purpose!
 
Welcome to MY world Lacogada! I have both the mixer and the interface (well the 202) and that noise is the CLASSIC bootprint of a Berry 16 bit converter being recorded into Windows with far to much gain (in Win)

Unless the mixer is faulty in some way or you are doing something incredibly stupid with the gains, it is not at fault. Looking at the noise spectrum, all the spikes from 1kHz up BANG on the number are the 222. The 60&120Hz hum I don't know the source of yet but they are NOT the 222 and almost certainly not the 802.

So, go into Windows Sounds & Devices (start btm right r/clk the speaker icon) and set the 'USB CODEC' as the 222 is probably called, for a recording gain of 5% from the default 100% and turn off any boosts. That is not a typo! FIVE! Now, driving the 222 the LEDs on the mixer should never blink above about '0' vu.

This is a short and dirty attempt to set things up, you might fail but come back and I will go through it more slowly and post some pikkies!

On the quality of the UCA 222? Yes, they are poor by todays standards but at 16bits they can get close to CD quality (about -85dBFS) For tape/vinyl dubbing they are fine. Recording the output of a synth should be fine as well, set max velocity to -6dBFS. I doubt many synth have a better than -80dB noise floor? I would not be AT ALL surprised to find that hum comes from the keys!

Dave.
 

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  • Specmix222.png
    Specmix222.png
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Just Googed the Roland. Yes, I eat H.P. looks very good. If the OP's cables are in good order then the hum could be a mains power 'line lump' too close to the 222 or the audio cabling. Line lumps put out hideous amounts of 50/60 Hz or hash if they are of the SMPS design. Does the Roland have an outboard PSU?

Dave.
 
Have you listened to the noise?

Sounds like a typical USB whine to me. Nothing to do with the Roland or the Behringer. Probably a bad ground connection in the computer, or a bad computer PSU.

Could the OP try with another computer?
 
Have you listened to the noise?

Sounds like a typical USB whine to me. Nothing to do with the Roland or the Behringer. Probably a bad ground connection in the computer, or a bad computer PSU.

Could the OP try with another computer?


Oh, yeah, that's a Behr USB whine for sure. Exactly what I got when I bought a Behr USB mixer (and I returned it the next day).
 
Oh, yeah, that's a Behr USB whine for sure. Exactly what I got when I bought a Behr USB mixer (and I returned it the next day).

The mixers are worse than the UCAs for some reason but all 16 bit USB audio converters of this ilk produce this noise.

My early A&H zed 10 does it and the guys at A&H told me it was unfortunate but inherent and it was they that put me onto the Windows gain issue. Once I had reduced the internal gain the Z10 had a noise floor of better than -85dBFS but RMAnny still shows the artefacts! They are just buried in incoming noise is all!

For the purposes the 202 and the mixers are intended the 'pub' noise will dominate the noise floor by tens of dBs. Same goes for tape or vinyl. I have recently (today!) had
some information that an old Juno synth has a noise floor no better than -60dBFS and MUCH worse if you turned the chorus on! A Roland bass synth was an impressive -89dBFS which beats the 202/z10 'on paper' but I doubt is a bother in practice.

Dave.

What for instance is the 'self noise of your monitoring chain?
 
Wow ... thanks for al the replies people, appreciate it.

There is only one receptacle near keyboard and computer and pretty sure the one breaker feeds that room.
Checked recep with tester and it showed correct wiring.
One power strip to recep.
Keyboard to power strip.
Another power strip to first power strip that feed computer and monitor.
Have one incandescent lamp near keyboard.
Nothng else on in room.

Good keyboard, crappy mixer .... Why are you even using the mixer in this chain?

Cause I do not know what I am doing. :)

My question to [MENTION=125767]lacogada[/MENTION] is whether the remaining noise is the same kind or different?

I'll record another clip and post it, right now I do not recall. Thanks

So, go into Windows Sounds & Devices (start btm right r/clk the speaker icon) and set the 'USB CODEC' as the 222 is probably called, for a recording gain of 5% from the default 100% and turn off any boosts. That is not a typo! FIVE! Now, driving the 222 the LEDs on the mixer should never blink above about '0' vu.
Dave.

Thanks for your explanation, will look into your suggestions.

Just Googed the Roland. Yes, I eat H.P. looks very good. If the OP's cables are in good order then the hum could be a mains power 'line lump' too close to the 222 or the audio cabling. Line lumps put out hideous amounts of 50/60 Hz or hash if they are of the SMPS design. Does the Roland have an outboard PSU?
Dave.

Cables are new. I think the answer to "outboard PSU" wold be yes.


Have you listened to the noise?
Sounds like a typical USB whine to me. Nothing to do with the Roland or the Behringer. Probably a bad ground connection in the computer, or a bad computer PSU.
Could the OP try with another computer?

Have a laptop I could try ... thanks!

Oh, yeah, that's a Behr USB whine for sure. Exactly what I got when I bought a Behr USB mixer (and I returned it the next day).

:):):) ... thanks !
 
Yeah, the USB (16 bit) on my Mackie mixer makes the noise, too, but it only becomes loud enough to record when boosting up the USB volume control on the mixer.
 
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"Have a laptop I could try ... thanks!" Do, by all means. W7? Perhaps I can make the reason for the problem simpler? The noise is, AFAIK, a FU in the early 16 bit converters and is a 'constant'.
The USB 'input' in W7 has a 'gain' set by the Windows software, when set too high it brings up the whine. If you reduce the software gain but increase the analogue drive* the whine goes down into the noise floor. Still there but 'masked' by mixer analogue noise and MOSTLY external noise.

The 222 is a handy device but as soon as you can move onto a decent audio interface and run it at 24 bits. That puts 'digital' noise SO low in the system that it is way better than any analogue device can get near to. A fairly mediocre 24 bit AI will return a noise floor of -100dBFS and the top flight jobbies better than -120dBFS. NOT! That you need such quality for anything you are likely to record!

*In practice you don't increase the drive, much. Be aware that the 222 has relatively low headroom but with care you can make very decent recordings. Note too that 'proper' AIs that can run 24 and 16 bits do not suffer the noise but there is really little reason to ever run at 16 bits if you don't have to.

Dave.
 
Have you listened to the noise?

Sounds like a typical USB whine to me. Nothing to do with the Roland or the Behringer. Probably a bad ground connection in the computer, or a bad computer PSU.

Could the OP try with another computer?

It's not the Behri that's at fault, it's the computer...

That said, a better interface might filter out that noise. But then you have to look at the price point. Some combo's interface/computer just don't work. USB mics are the worst. But also USB-to-guitar cables and stuff like that.
 
It's not the Behri that's at fault, it's the computer...

That said, a better interface might filter out that noise. But then you have to look at the price point. Some combo's interface/computer just don't work. USB mics are the worst. But also USB-to-guitar cables and stuff like that.

If you mean "the way Windows IN computers handles certain 16 bit interfaces" Cy' I will agree with you.

It is certainly not a "fault" in hardware as I have had the problem with everyone of some 3 laptops and 3 desktops I have tried. I have not so far tried a 'crap' 16 bit AI on a W10 machine, might do that but because 24 bit AIs are now so common the problem is becoming less common. Of course, so long as the 202/222 interfaces and V cheap USB mixers are around they will suffer the issue but it IS fixable to a degree that make the kit OK for many purposes, e.g. cassette dubbing.

It is not a "filtering" issue but an inherent noise that needs the gain structure changing.

Dave.
 
It's a power issue.

The whine is the USB handshake getting into the audio because the 5V from the computer isn't filtered.

It shows with a lot of USB powered audio interfaces. The same gear, if powered externally, doesn't show the problem. Of course, the Behri isn't USB powered. In this case, it's a ground problem in the computer.

I've got a test cable for such cases. The 5V wire is interrupted and connected to the lab supply set at 5V. That way, you can always power a device externally, even if it doesn't have a power connector. Thta usually solves the problem immediately.

Some mics, like my AKG C451's, draw too much current and behave oddly on any USB powered interface, including my Sound Devices USB Pre. The internal converter that turns 5V into 48V phantom power can't cope. Sometimes, they motor boat, sometimes it takes a minute to power up, sometimes it silently fails.

5V, 500 mA is only 2,5W. A mic preamp needs about 0,5W, the headphone amp needs about one W. There's no "headroom" in the power department.

Of course, some computers can supply a lot more power. But most can't. And USB3 should be able to supply a lot more, but I've seen computers that can't even supply 2,5 W on USB3. If you add a real skinny USB cable, it might drop the 5V to 4V. Not enough juice for the digital parts.

And then, some computers have a bad ground somewhere in the case. Mostly desktops and it can be solved sometimes. I've seen cases where tightening the screw on the ground cable solved it.

The same kind of interference can happen with Wifi and Bluetooth. There was a run of Mac Mini's where a tiny self-adhesive shield was missing or not placed properly and those all had problems with audio interfaces. That was an easy fix, once we knew where to look.

The problem hardly ever shows on Firewire, because FW supplies 9 to 30V and should also supply more current. Macs typically supply 15V, 1A. That's 15W to work with. And FW has better filtering, in general. That said, I've seen PC FW cards that supplied 5V on the FW connector. These will still work with a HD with external power, cause the HD detects the 5V and starts the disk. But it won't work with a FW powered external disk, cause these need 12V too. And it won't work with FW bus powered devices, like an RME FF400, cause that one needs about 11V at least. The internal converter doesn't work below 10V and it only works with 10-11V if there's enough current. FW PC cards that supply 9V in general only supple 1A max. Usually less. Not enough to drive a FF400.

And in some cases, it's a sign of a slowly dying PSU in the computer. Usually due to overheating from dust...
 
To answer earlier question about noise sound with just the UCA222 in chain ...
sound is the same, highpitched whine but not as loud.

Reducing Win recording level to 5% did make the noise very low but recording from
piano very low also. That was with mixer and uc222 or with uc222 alone.

Someone mentioned tryinging different computer.
Laptop hooked up with mixer and uca222 and win recording level at 50%.
Noise was a little lower and it did not have the high pitch whine.
The piano notes seemed cleaner and waveform looked more normal (to my inexperienced eye)

NOTE: Laptop does not have battery, so it was plugged into same power strip all coming from same receptacle.
 
Oh, and Windows adds to the problem, trying to help.

But I don't use Windows...
Hmm? Well I cannot argue with your computer knowledge Cyrano and I no longer have access to a lab but I think your 'power' arithmetic is a little off!

2 Mic pres at 0.5W I will give you but a bit high IMHO.

Phantom power: IF any AI was capable of the actual spec of 10mA per input a 100% efficient converter would pull 0.2W for two channels so let's go 0.4W for jazz?
One watt for headphones? You deaf? The first AI I found a H/P spec for was the very popular 2i4. 24mW per channel. say 50mW all up (and it will be a class AB drive circuit)

With the digital converters that still leaves us way short of 2.5W and in fact I have just checked my NI KA6 and it pulls 0.4A at 4.98V say 2W? But THAT has 2 pres, 2 balanced line ins, 4 balanced line outs, S/PDIF in and out and fekkin' MIDI! But, MORE to the point the KA6 does not suffer ANY kind of noises no matter which of many desk and laptops it has been used with.

Then again, I have never read of anyone having this problem with a regular 24 bit AI. The noise is PECULIAR to 16 bit converters AS used in early mixers and such gear. I do not believe a good firm like Allen and Heath would have left the issue on their gen1 ZEDs IF it had been a simple matter of filtering? There is also the point that the Zeds are mains powered so IF it was USB supplies that caused the noise they could simply have grabbed a bit from the mixer's supply.

I do not know the PRECISE cause of the 'whine' but the evidence I see rules out 'dirty' supplies.

Since only early 16 bit devices have the problem and people like A&H and Soundcraft have now gone over to 24 bit converters we can now I think confine the whine to an historical cockup.

Dave.
 
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