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DC power vs AC power

It's a balanced XLR interconnect system not just a cable.

balanced output stage >> interconnect cable >> balanced input stage.
 
Might be the time to stop here (to not blast the DC-driven whateveritwas again ;):facepalm:)
No I didn't blow anything up, I never do anything without learning the ins and outs of something
 
Those will not generally break a ground loop.


I talked to a retired electrical engineer, he said that he connected an online UPS to the system for the noise problem coming from the speaker and it worked.

I don't know if the noise was due to ground loop or if there was another reason.

so I thought maybe that was one of the reasons why studios used it
 
No I didn't blow anything up, I never do anything without learning the ins and outs of something
That blast item was not directed to You personally but me :rolleyes: (Moderators will know).
 
I connected the guitar to a EQ pedal with a jack, then I connected EQ pedal with xlr cable to the interface. It got much worse. Maybe a jack-xlr cable would work.
OK - we are talking about XLR being used for balanced line level analogue interconnect between audio reproduction gear. What is the interface between EQ pedal and audio interface? Because this is far outside the topic of conversation regarding ground loops in audio reproduction gear.
 
OK - we are talking about XLR being used for balanced line level analogue interconnect between audio reproduction gear. What is the interface between EQ pedal and audio interface? Because this is far outside the topic of conversation regarding ground loops in audio reproduction gear.
System is guitar-eq pedal - interface
 
I connected the guitar to a EQ pedal with a jack,
Not necessarily a "ground loop problem" but guitars are a special problem. They are high-impedance unbalanced which makes them prone to noise-pickup. Plus, the pickup is a coil intended to pickup electromagnetic signals and it's just as good at picking up electromagnetic noise. As I'm sure you know, buzz and hum are common. Any amplification or compression will boost the noise.

Most pedals are battery powered and active. The fact that they are active means that the pedal output usually has much lower impedance so from that point on your signal chain is more noise-resistant.

A common solution to guitar buzz/hum is a noise gate. A noise gate kills the audio completely when the volume drops below a threshold. Ideally, it kicks-in when there is no signal and only noise. But in the real world it will cut-off the last bit of your sustain. Usually nobody will notice if you are mixing the guitar with the whole band. There are noise gate pedals but it's often a plug-in the DAW.
 
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My hypothesis (I don't know if you know better or if it has already been proven) is the sound quality better with DC power than with AC power? Because DC does not need ground as much as AC. I want to run the system with only DC power.

I want to run my system completely DC power is it wrong?
? !!!!! ?!? ? ! Or, to be brief, yes, you are wrong on all counts. There can be an argument for running very low level high gain preamps such as MC preamps on batteries, but that IMHO is just to avoid the effort of designing a good PSU - or perhaps for prototyping. AC power is used for distribution and rarely used directly, it is converted to DC. And we have 100 years ++ experience of how to do so very well.
 
I talked to a retired electrical engineer, he said that he connected an online UPS to the system for the noise problem coming from the speaker and it worked.

I don't know if the noise was due to ground loop or if there was another reason.

so I thought maybe that was one of the reasons why studios used it
Yah, well, I am a retired EE, not that it matters.

Studios use them (UPS) for the same reason I do at home and we had many of them (including a huge building-level backup) at work, to protect the equipment during brief outages, keep things running to prevent data loss, and provide time for orderly shutdown if needed.

Putting anything in the power line, UPS, power conditioner, or just an extension cord, changes the ground impedance so it may help -- or hurt.
 
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You'd be surprised how many synthesizers and FX devices don't have balanced in/outputs. Infact, the majority doesn't.
Absolutely, which is why there are cupboards full of DI boxes etc. A good installation can cope with the occasional SE device, but it leads to unpredictability. If a band is rich and has weeks in the studio, or build their own studio, it's up to them what they do. But for a lot of recordings, time is tight and the whole thing needs de-rigging, then rigging every couple of days. So, chasing down the device causing the problem is musician time and producer time wasted.
 
Absolutely, which is why there are cupboards full of DI boxes etc. A good installation can cope with the occasional SE device, but it leads to unpredictability. If a band is rich and has weeks in the studio, or build their own studio, it's up to them what they do. But for a lot of recordings, time is tight and the whole thing needs de-rigging, then rigging every couple of days. So, chasing down the device causing the problem is musician time and producer time wasted.
Exactly. Go into a studio for a session and you'll find DI boxes scattered all over the floor for the guitars and sometimes keyboards to plug in to so they can avoid wasting valuable (and expensive) time debugging a ground loop.
 
Yah, well, I am a retired EE, not that it matters.

Studios use them (UPS) for the same reason I do at home and we had many of them (including a huge building-level backup), to protect the equipment during brief outages, keep things running to prevent data loss, and provide time for orderly shutdown if needed.

Putting anything in the power line, UPS, power conditioner, or just an extension cord, changes the ground impedance so it may help -- or hurt.
Ok I completely understand it. Thank you all. Great forum! Oh my god
 
Not necessarily a "ground loop problem" but guitars are a special problem. They are high-impedance unbalanced which makes them prone to noise-pickup. Plus, the pickup is a coil intended to pickup electromagnetic signals and it's just as good at picking up electromagnetic noise. As I'm sure you know, buzz and hum are common. Any amplification or compression will boost the noise.

Most pedals are battery powered and active. The fact that they are active means that the pedal output usually has much lower impedance so from that point on your signal chain is more noise-resistant.

A common solution to guitar buzz/hum is a noise gate. A noise gate kills the audio completely when the volume drops below a threshold. Ideally, it kicks-in when there is no signal and only noise. But in the real world it will cut-off the last bit of your sustain. Usually nobody will notice if you are mixing the guitar with the whole band. There are noise gate pedals but it's often a plug-in the DAW.


The noise gate kills the tone that I want ( bass guitar bite- low bass , high treble)unfortunately. My goal is to increase the signal/noise ratio, but if that's not possible, there's nothing to do.
 
Please can edit your first post. Please add a paragraph explaining that your focus is reducing noise in your electric guitar, pedals and interface set-up. I assumed (and I suspect others did as well) that you were talking about domestic HiFi.

You would have received direct and helpful advice much sooner if you had been clearer!

Have you considered experimenting with a DI box?
 
My hypothesis (I don't know if you know better or if it has already been proven) is the sound quality better with DC power than with AC power? Because DC does not need ground as much as AC. I want to run the system with only DC power.

I want to run my system completely DC power is it wrong?
Most of the single-line replies you've received have been 100% unhelpful. I'm afraid this is often a feature of this particular forum.

However let's first ask why you are thinking of using DC and where you will get this DC from?

Vinnie Rossi's Red Wine Audio used to use batteries to power their highly regarded kit (including power amps) about 20 years ago, but they have now moved away from batteries, I believe. There is very little gear (apart from automotive) at any price level that uses DC via batteries. I often wonder why, but explanations about capacitance or whatever else, may be part of the reason. AC just seems a lot easier provided your kit has excellent power supplies and good ways of rejecting RFI, etc. There should be no need for costly "mains conditioners", "regenerators", etc but I understand the quality of AC in the US is often pretty poor and this encourages dealers to flog the notion that these are essential for good music in the home - and of course ridiculously costly power cables! None should be necessary with well-designed kit.

DC cannot easily be changed from one voltage to another and the battery voltage will vary quite a bit between fully-charged and in need of recharge. Good AC power supplies will maintain a steady DC output over a very wide variation in AC supply.

I did own a Red Wine Signature 30 Mk II amp, but I never got along with it powering my Avantgarde horn speakers, despite mods by RW to match the amp's gain for my speakers and install a new type of battery. I sold it after a couple of years and have been AC since then.
 
Please can edit your first post. Please add a paragraph explaining that your focus is reducing noise in your electric guitar, pedals and interface set-up. I assumed (and I suspect others did as well) that you were talking about domestic HiFi.

You would have received direct and helpful advice much sooner if you had been clearer!

Have you considered experimenting with a DI box?
ground lift di box was of little use, it would have been better if it wasn't

I don't know the forum jargon, I'm new, but this post is about bass guitar setup.
 
DC cannot easily be changed from one voltage to another and the battery voltage will vary quite a bit between fully-charged and in need of recharge. Good AC power supplies will maintain a steady DC output over a very wide variation in AC supply.
DC voltage can easily be converted to a lower regulated Voltage.
DC voltage can be converted to a higher DC voltage using a Switch Mode Power Supply, but there may be other issues.
 
Friends that's true?
 

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