Quiet(ish) studio monitors...

[NancyJohnson]

Hopefully someone will have a solution for this.

 

I use a Focusrite Scarlett 2i2 audio interface for recording and audio playback; this feeds a pair of M-Audio BX5 powered monitors. 

 

When I changed computers a couple of years ago, the audio became very noisy (electric static) but there wasn't any issue with the volume of the monitors, just the crackling.  There wasn't an issue with recordings when I used the interface, everything was clean.  (The signal path was simple, USB to the interface, 1/4" jacks from the interface direct into the monitors.  The interface is 1/4" jack output only.)  The monitors were set to about 50% and the interface output to about 20-25%; even at this it would get too loud at times.

 

To resolve the static issue, I bought a Palmer dual channel/stereo passive DI box, ran 1/4" jacks to that and then XLRs to the monitors.  The electrostatic crackling stopped (woop), but there's been a noticeable drop in volume from the monitors, so much so that I now run the monitors at 100% and the interface at about 50%.  There's no way to tweak the interface up and there's nothing on the Palmer aside from a 0/-30db button (I'm running the DI at 0db).  PC output is at 100%.

 

I know this is a first world problem; but I'm just trying to get to the bottom of why everything has gone a bit quiet.

 

 

[BigRedX]

IIRC I asked some questions about the set up when you originally posted this problem, and I don't think you ever answered.

 

As I said previously, to me this sounds like an earthing problem. How are all the devices in your signal chain powered? Built-in or external PSUs? Is the interface powered via USB?

 

Check the mains plugs on all the devices, I suspect that one or more of them will have a plastic earth prong which is where the problem lies. The Palmer DI box gets around the earth problem but at the expense of lowering the signal level and therefore is introducing a new problem while bypassing (rather than fixing) the old one.

 

What leads are you using the connect the outputs of the interface to your speakers? IIRC all the inputs and outputs on Focusrite interfaces are balanced. It may also be possible to fix the problem by using special leads to connect the speakers that have the +ve and -ve signal connections but not the earth (that's pins 2 and 3 on an XLR and TR but not S on a TRS jack).

 

HTH.

[NancyJohnson]

I honestly had no recollection of posting this previously!

 

To answer the questions, the interface is powered by a USB cable from the OC and the Palmer is passive/unpowered.  Cabling is (standard?) off the shelf stuff; everything has been used in other applications previously.  The power cables to the monitors are the same ones that were in the box when I bought them new.

 

I've tried all manner of problem solving, but just couldn't resolve the crackling/static issue.  

 

I reached the passive DI solution after turning up a video by a sound engineer on You Tube...it resolved the issue immediately, but introduced another in the guise of reduced speaker volume/output.

 

 

[BigRedX]

The problem may well be that your are using standard cables when your particular configuration will require custom ones, but we'll worry about that later if all the other solutions fail.

 

Is this the DI box you have? If not could you post a link to yours? If it is does it make any difference to absence/presence of the static noise if you change the ground lift settings?

 

Also what's your PC - a desktop or laptop?

[NancyJohnson]

That's the DI box, yes.  (It was the one in the video I mentioned earlier.)

 

Interestingly there's no difference to things tonally with the ground-lift button in or out.  PC is a desktop (HP).

 

The current XLR cables are these:
https://www.amazon.co.uk/gp/product/B01CUI6I0A

 

The 1/4" jack to jack cables are these:

https://www.amazon.co.uk/gp/product/B01CSVQ264

 

I was out to lunch with a mate of mine yesterday and he asked a very obvious question...wouldn't I be better off just buying a pair of jack-XLR cables?  I didn't have an answer.

[Jack]

Well it occurs to me that the jack cables you were using aren't balanced, so you might be able to replace the cable>di>cable rig with a trs to xlr cable, but I'm not sure what's causing the noise, so I'm not sure if that would fix it.

 

I'd be tempted to try hooking everything up to one power strip that is plugged in to one socket and see if that helps.

Edited December 19, 2022 by Jack

[BigRedX]

If the problem started when you switched computer I suspect it is the culprit regarding earthing. Can you post a link to the EXACT model. Many desktop PCs these days are essentially laptops in a desktop box with the PSU built in and this may well be causing your earthing issue.

 

I see that you are running TS jacks from the interface so you are not getting the benefits of the balanced connection between it and the speakers. It is also my experience with Focusrite interfaces (I've owned two different ones) that they work best when all the connections are balanced. 

 

I would start by taking your mate's (and @Jack's) suggestion and buying a pair of decent quality TRS jack to XLR leads to connect your interface direct to the speakers. Be prepared to have to cut the earth (screen) at one end of the cable if the static noise comes back.

 

If that doesn't work have a look at replacing the Palmer DI box with an ART DTI Box which does the same thing as the DI box but maintains same signal the level either side. However this is a very last resort solution.

[Chaddy]

The palmer will be sucking all the "energy" away due to the resistant changes and impedance. 

TRS cables give a noticeable difference, I use the BX-8's myself ( Jack to XLR ) - all your ports are Balanced. 
Have you tried powering your Audio interface by power socket and not USB? Does this clean up the signal at any point without the DI box? 

 

 

[mario_buoninfante]

It's not possible to power the 2i2 in any other way other than via USB (computer port). The device needs the enumeration part to properly boot.

Edited December 19, 2022 by mario_buoninfante

[mario_buoninfante]

I second what the other guys have been saying. If you can, try a different computer, and if you don't have one you could try with your phone/tablet too, the 2i2 is class-compliant.

Then, good if you can get better TRS cables too. Outputs on the device are balanced and I suspect (didn't check though) the input on your monitors is too.
Once you get the TRS cables, I'd recommend to try bypassing the DI box too.

[NancyJohnson]

OK, let's address things!  (In no particular order):

 

PC is an HP Pavilion D550 or D580FPA.  2.7ghz 64bit.  It's not feasible to try a different PC at this juncture.

 

The Scarlett doesn't allow for an additional power supply; it's USB from PC/laptop only:

 

 

I've tried powering the monitors from a different plug (I ran an extension from another room). I was still getting the static/crackle.

 

Question.  The monitors have "TSR" printed above the 1/4" jack socket - feasibly if I bought a pair of these, it might solve things?  I just took a look at the manual for the interface - this is saying balanced/TSR cables.  I don't mind throwing a little more swag at it:

 

https://www.amazon.co.uk/Professional-Instrument-AkoaDa-Interconnect-Equalizer/dp/B095WMLY1L/ref=sr_1_24?crid=5SEVCBYBATMN&keywords=trs%2Bcable%2B4m%2Bright%2Bangle&qid=1671447860&s=musical-instruments&sprefix=tsr%2Bcable%2B4m%2Bright%2Bangle%2Cmi%2C60&sr=1-24&th=1

 

What does seem the oddest is that the old PC (a very old Dell) ran the interface which then ran the monitors without any issues.  Standard jack cables, crackle free.

 

[Huge Hands]

Apologies if I am repeating what someone has already told you, bu the reason your DI box has made the volume drop is because your DI box effectively drops the the level input signal to mic level to allow long runs over XLR (the same as pressing a line pad button on a mixer input).

 

Are you using balanced (stereo) 1/4" jacks from the interface, or unbalanced (mono).   

 

The interface having TSR on it could be the same as TRS (tip ring sleeve) which would suggest to me they support balanced jacks.

 

If you are using balanced and are happy to mess around with your cables you could try wiring it back up as interface straight to speakers, then chopping off the ground connection at the XLR end (tape it up so it doesn't catch anything).  This should prove/rule out any ground loop theory.  Obviously this won't work if you are using unbalanced jacks.   

 

Happy to PM if you want any more info.

Edited December 19, 2022 by Huge Hands

[BigRedX]

One other suggestion: have you tried ALL the USB ports on your computer? 

 

They will not be all the same and different ports may well be on different buses internally and sharing the bus with various other "hidden" USB peripherals such as the wifi and bluetooth as well as the more obvious ones like your keyboard and mouse. Also depending on where they are on the casing the earthing may be different.

 

So reconnect your speakers direct to the interface and then try each USB socket on the computer in turn to see if it makes any difference to the noises.

 

Edit: I've just looked at the computer in question on the HP web site and there appear to be 6 USB ports and since 4 of the them are UCB3 and 2 are USB2 there should be at least 2 separate USB busses, but try them all anyway. Does anyone know if there is a Windows equivalent for the System Profiler on Mac OSX? This is a very handy tool as it will let you see exactly what devices are on each USB bus and which physical ports are connected to which bus.

 

The other thing you could try after this is if you have a POWERED USB hub to see if running the interface from this makes any difference.

 

USB can be quite "eccentric". I fixed a USB problem with my Novation controller keyboard not working reliably simply by using a different USB socket on the computer.

Edited December 19, 2022 by BigRedX

[NancyJohnson]

Yep, tried all the USB outs.  I have a powered hub, so I'll give that a punt.

 

I've ordered some TSR cables.  Let's see what happens there.  Delivery Wednesday.

[Huge Hands]

1 minute ago, NancyJohnson said:

Yep, tried all the USB outs.  I have a powered hub, so I'll give that a punt.

 

I've ordered some TSR cables.  Let's see what happens there.  Delivery Wednesday.

Try them first without chopping any connections off - you may be pleasantly surprised!

 

[mario_buoninfante]

I know this might be tricky, but if you could share a recording of this crackle (even made with a phone), it might reveal a bit more about the issue

[NancyJohnson]

32 minutes ago, mario_buoninfante said:

I know this might be tricky, but if you could share a recording of this crackle (even made with a phone), it might reveal a bit more about the issue

 

To be honest, to restore/unplug everything to get the static/crackle back is going to be more hassle than it's worth right now!  I'll wait for the new cables to arrive before I pull everything out (again).  If these don't work, I'll throw the original cables back in and do you a recording.

[tauzero]

The TRS ought to help - one other factor is where the cables run, in moving computers you may have put the cables somewhere where there is a large electromagnetic field.

 

My own experience with a 2i2is that it's connected up to a Behringer mixer using straight TS jack-jack cables and I don't get any crackles. Although this has started me thinking, and as the inputs on the mixer are TRS, I'm going to upgrade.

[Chaddy]

20 hours ago, NancyJohnson said:

Yep, tried all the USB outs.  I have a powered hub, so I'll give that a punt.

 

I've ordered some TSR cables.  Let's see what happens there.  Delivery Wednesday.

I "think" you can power from non USB PC port and still hear your guitar from the input's, will just simply boost the connection in. Not sure if that will give any difference or if that make it clean ( Active monitoring on? ) 

Which is what I was referring to, but I didn't explain that in my original post. My bad. 

 

[mario_buoninfante]

1 hour ago, Chaddy said:

I "think" you can power from non USB PC port and still hear your guitar from the input's, will just simply boost the connection in. Not sure if that will give any difference or if that make it clean ( Active monitoring on? ) 

Which is what I was referring to, but I didn't explain that in my original post. My bad. 

 

that wouldn't work. Scarlett 2i2 needs to enumerate via USB  (aka being connected to a computer/phone/tablet) in order to fully boot.
 

Edited December 20, 2022 by mario_buoninfante

[NancyJohnson]

*Just got an Amazon notification that the cables will be here before 4.30pm.  All will be revealed!

[NancyJohnson]

Cables have arrived and all sorted.  Loudness has returned.

 

Thanks t'all!

[mario_buoninfante]

did you try bypassing the DI?
I would avoid having a DI between audio device and monitors.

[SH73]

I had the same issue with my Sony VAIO laptop, I replaced HD with SSD, I bought a new power cable, noise isolator (after watching YouTube and reading Amazon reviews, utterly useless, went back for refund), shielded guitars, new guitar cable and nothing. two years ago I bought a new gaming PC just for music playing, recording , and all problems disappeared. Problem solved. All I hear is my tinnitus now.

[NancyJohnson]

It is all a bit odd how a different PC can just wreck things.  Thinking back, I also had an issue disabling some B&O software on it that was processing audio as well.

 

I'm not on the market for another desktop, but I won't buy another off the shelf/one-size-fits-all PC again.