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XLR output to RCA input done properly?

solderdude

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Without studio knowledge, I won't match DAC XLR to any RCA input.

You won't, I have no issues with it and unless a ground loop occurs that cannot be fixed with other means or the DAC in question has a transformer in its output I would not use a DI box.

Again... a guitar is not remotely similar to a DAC.
 

kongwee

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You won't, I have no issues with it and unless a ground loop occurs that cannot be fixed with other means or the DAC in question has a transformer in its output I would not use a DI box.

Again... a guitar is not remotely similar to a DAC.
DI has differential circuit too. The key word is differential.
 

solderdude

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Of course. That's why it exists.
NOT needed for connecting a balanced DAC to an RCA input amp but it could be used for that. That doesn't mean you need a DI box to do so. All DI boxes will add distortion and limit FR. Show me one that doesn't. A cable won't and will work well in home audio situations.
 

kongwee

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All DI boxes will add distortion and limit FR. Show me one that doesn't. A cable won't and will work well in home audio situations.
Nope, a well design differential DI boxes retain as much signal integrity as possible. This is why you want balanced XLR. Differential signal end to end. DI box received the differential signal and convert it to RCA. Some even have gain matching. ART have one such product. That is a huge plus better than passively done. Nowadays studio is in your home. I just suggest another alternative to preserve signal integrity. Having a passive adapter for the worst scenario is high hiss noise. I won't bet on it.
 

tonycollinet

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Technically should get DI boxes to correctly convert differential signal to single end. That another piece of component. Those XLR to RCA you can use that too. For me there is different doing it activity and passively . Someone will scream no different.
Are you sure they are going to scream it? Perhaps they will just write it? :cool:
 

tonycollinet

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Assuming by removing pin 3 with a voltage drop will not affect the signal. In real world no. signal still affected. It is just like cover your ear with a cloth. You can alway tell your mind, there is no different.

If introduce distortion, the sound engineer will not handle you their DI boxes whether your pedal board has the same function or not.
There is no perfect electronics. All electronics introduce distortion, in a way that simple wires do not. Sure - a converter cable might give you ground loop pickup if you have a ground loop - but it is cheap and easy to check.
 

Ricardus

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The correct answer is to use the THAT balancing chips as I mentioned in my previous post.
 

tonycollinet

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The correct answer is to use the THAT balancing chips as I mentioned in my previous post.
But for that you need a PCB, Box, dual rail power supply etc etc. Quite a pain in the proverbial.

On the other hand you can use a simple cable, connect one output channel of the balanced to the input of the RCA - job done, and probably less impact on noise/distortion than an electronic solution - as long as you don't have ground loop noise.
 

Ricardus

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I have PCBs that would share for a very small price and the cost of freight. But yeah, the bi-polar PSU is a slight complication. But hey. It's worth it. I'll be using a filtered Meanwell SMPS. Or maybe I'll build a small linear. Haven't decided yet.
 

sergeauckland

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But for that you need a PCB, Box, dual rail power supply etc etc. Quite a pain in the proverbial.

On the other hand you can use a simple cable, connect one output channel of the balanced to the input of the RCA - job done, and probably less impact on noise/distortion than an electronic solution - as long as you don't have ground loop noise.
Exactly this. A cable correctly wired is the simplest and usually the best way of handling balanced to unbalanced and vice-versa connections.
In the case of a ground loop causing hum, then use transformers, or even electronic balancing but at a cost.
As to which is better, electronics or transformers, either will do a decent enough job. Transformers automatically provide galvanic isolation, although there is a small increase in distortion at LF. Electronics doesn't have the small increase in LF distortion, but don't provide full galvanic isolation and add a small amount of noise. Take your pick.

S.
 

SoundOfMind

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Exactly this. A cable correctly wired is the simplest and usually the best way of handling balanced to unbalanced and vice-versa connections.
In the case of a ground loop causing hum, then use transformers, or even electronic balancing but at a cost.
As to which is better, electronics or transformers, either will do a decent enough job. Transformers automatically provide galvanic isolation, although there is a small increase in distortion at LF. Electronics doesn't have the small increase in LF distortion, but don't provide full galvanic isolation and add a small amount of noise. Take your pick.

S.
If the cables are short and there isn't any hum, then using "half" of the balanced output to an unbalanced input is the best solution. I am planning a home theater with four subwoofers, using four outputs from the sound processor. The previous generation SVS PB-2000 is on sale and will do nicely, but it has an unbalanced input. I like the common mode noise reduction a balanced wire provides over a longer distance, so balanced cables will be pulled. First, I will test by using one side of the balanced cable to verify that there is no undesirable noise. If there is noise, then a raw Jensen transformer will cost about $75 per sub. Seeing as an engineer from Jensen participated in the design of the chip in the Sparkfun THAT 1206 kit, it could provide similar results to the Jensen transformer and would be cheaper. Power for the boards could be provided by using two JAMECO RELIAPRO DDU050100M2270 to supply positive and negative 5 VDC for all four boards. All told, that's about the cost of one transformer. There is no perfect and it seems that moderate distortion from either transformers or added electronics is easier to tolerate in a sub than in full range speakers.
 

Ricardus

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I don't know how much gain will be passed through the circuit, but having more than 5 volts might be wise just so you don't hit the rails. When I build my THAT box, I'll be using +15/-15 just to have the headroom.
 

Chrispy

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Some definite crazy around here. So basic to make such a cable if needed rather than buy silly sh*t....
 

Chrispy

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There are DI boxes that is differential that compatible with differential incoming signal. Differential ops am in these DI. It is just like adding differential input for your amp that don't include one.
At what cost particularly?

(to the signal not $$ cost)
 

kongwee

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At what cost particularly?

(to the signal not $$ cost)
It is correct circuit to implement. You use balanced XLR because of differential signal as a medium to pass signal. Both end must have differential circuit in them. After the signal pass through these differential circuit then you have the correct analog signal for those amplifying circuit or other process. DI is adding a differential circuit if you need to. Of course the DI box must be differential.
 

tonycollinet

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If the cables are short and there isn't any hum, then using "half" of the balanced output to an unbalanced input is the best solution. I am planning a home theater with four subwoofers, using four outputs from the sound processor. The previous generation SVS PB-2000 is on sale and will do nicely, but it has an unbalanced input. I like the common mode noise reduction a balanced wire provides over a longer distance, so balanced cables will be pulled. First, I will test by using one side of the balanced cable to verify that there is no undesirable noise. If there is noise, then a raw Jensen transformer will cost about $75 per sub. Seeing as an engineer from Jensen participated in the design of the chip in the Sparkfun THAT 1206 kit, it could provide similar results to the Jensen transformer and would be cheaper. Power for the boards could be provided by using two JAMECO RELIAPRO DDU050100M2270 to supply positive and negative 5 VDC for all four boards. All told, that's about the cost of one transformer. There is no perfect and it seems that moderate distortion from either transformers or added electronics is easier to tolerate in a sub than in full range speakers.
Exactly the approach I'd take.

And despite the comments about distortion in electronics (including mine) in decent chips (such as those used in the sparkfun modules) it will be inaudible - Sub or not.
 
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