Balanced vs Unbalanced Interconnects

[vivek.batra]

(in no particular order)

SONCOZ SGD1
ADI-2 DAC
SU-8
Benchmark DAC3
Aune S6
DX7S
D70
DAC magic Plus (Cambridge)
UD501

there is plenty around.

Luxman is the easiest one for me to buy locally. I didn't find anything about Luxman DA 250 dac. Would you put this on the list that you shared?

 

[solderdude]

It's not tested here but the specs and measurements that are out there say it is a good device.
The DA200 is another option

 

[PenguinMusic]

Hi,

Your budget for the DAC is 3 000 dollars ?

Woah... You can take whatever you want. More or less.
If that is the case, I'd suggest to take the one that has a look that matches your amp

 

[vivek.batra]

Hi,

Your budget for the DAC is 3 000 dollars ?

Woah... You can take whatever you want. More or less.
If that is the case, I'd suggest to take the one that has a look that matches your amp

Yes that's right USD 3k. Looks wise Luxman Da 250 matches the best with Luxman 590 AX II. I am lusting for that but not much out there to read and reviews. Don't know why Luxman has no name in dacs.

 

[Speedskater]

Will it be right to say, if a dac has XLR outputs and rca outputs as well, then it has fully balanced circuit?

A balanced output circuit stage, yes.
* * * * * * * * *
some power amplifiers have a balanced input stage, then all internal circuits are balanced and a balanced power output.

 

[Speedskater]

DACs and amps sporting XLR connectors (usually combined with RCA) are bound to be more expensive than gear with just RCA.

With the exception of the connector, the manufacturing cost difference should be under 5 dollars.

 

[vitalii427]

(in no particular order)

SONCOZ SGD1
ADI-2 DAC
SU-8
Benchmark DAC3
Aune S6
DX7S
D70
DAC magic Plus (Cambridge)
UD501

there is plenty around.

You forgot D90 ))

 

[solderdude]

and so many others ...

 

[knobtwiddler]

Electronically balanced inputs have more hiss than unbalanced - fact. Transformers have virtually no hiss, but increase THD - fact
Unless you need the CMR afforded by balanced operation, there is little reason to adopt it (I.e. light dimmers etc. RFI/ hum fields into cables).
Fully balanced from I/P to O/P is the absolute best, with no noise penalty (in fact it can be quieter). But every time you interface balanced with unbalanced you pay either a noise (active) or THD (transformer) penalty. Only use balanced where you need, if ultimate noise figures are your goal.

 

[vivek.batra]

Electronically balanced inputs have more hiss than unbalanced - fact. Transformers have virtually no hiss, but increase THD - fact
Unless you need the CMR afforded by balanced operation, there is little reason to adopt it (I.e. light dimmers etc. RFI/ hum fields into cables).
Fully balanced from I/P to O/P is the absolute best, with no noise penalty (in fact it can be quieter). But every time you interface balanced with unbalanced you pay either a noise (active) or THD (transformer) penalty. Only use balanced where you need, if ultimate noise figures are your goal.

Good to know this.

 

[MediumRare]

Wow, there's a lot of BS in this thread. The main reasons to use balanced are two:

- Eliminate ground loops
- Raise the signal level to improve SNR

Also:

Better common-mode noise rejection is another reason, especially for long mic runs.

That's why all pro setups use balanced interconnects exclusively.

Some amps have better signal balanced chains, so you can pick up a few more dB there as well.

In addition, SOME DACs have better signal quality (SINAD) from their balanced outputs than RCA, but not all. So check the measurements published here. There is zero reason to spend more than $1,000 on a DAC, many people here would say $100 is plenty. Check out the Topping D90 (DAC only) and DX7 Pro (DAC plus headphone amp) and you can have SOTA balanced out for $600 or less. There are audibly equivalent ones for under $300.

Net across the whole signal chain you might come out as much as 20 dB better. Is it audible? Hmmmm, can't say. But why not. (And don't spend for than $25 on any cable, BTW.)

Edited to include @DonH56's valuable comment.

 

[vivek.batra]

Wow, there's a lot of BS in this thread. The main reasons to use balanced are two:

- Eliminate ground loops
- Raise the signal level to improve SNR

That's why all pro setups use balanced interconnects exclusively.

Some amps have better signal balanced chains, so you can pick up a few more dB there as well.

In addition, SOME DACs have better signal quality (SINAD) from their balanced outputs than RCA, but not all. So check the measurements published here. There is zero reason to spend more than $1,000 on a DAC, many people here would say $100 is plenty. Check out the Topping D90 (DAC only) and DX7 Pro (DAC plus headphone amp) and you can have SOTA balanced out for $600 or less. There are audibly equivalent ones for under $300.

Net across the whole signal chain you might come out as much as 20 dB better. Is it audible? Hmmmm, can't say. But why not. (And don't spend for than $25 on any cable, BTW.)

Hi

Thanks for you valuable advice. I will definitely keep this in mind.

 

[DonH56]

Wow, there's a lot of BS in this thread. The main reasons to use balanced are two:

- Eliminate ground loops
- Raise the signal level to improve SNR

That's why all pro setups use balanced interconnects exclusively.

Some amps have better signal balanced chains, so you can pick up a few more dB there as well.

In addition, SOME DACs have better signal quality (SINAD) from their balanced outputs than RCA, but not all. So check the measurements published here. There is zero reason to spend more than $1,000 on a DAC, many people here would say $100 is plenty. Check out the Topping D90 (DAC only) and DX7 Pro (DAC plus headphone amp) and you can have SOTA balanced out for $600 or less. There are audibly equivalent ones for under $300.

Net across the whole signal chain you might come out as much as 20 dB better. Is it audible? Hmmmm, can't say. But why not. (And don't spend for than $25 on any cable, BTW.)

Better common-mode noise rejection is another reason, especially for long mic runs.

 

[knobtwiddler]

Better common-mode noise rejection is another reason, especially for long mic runs.

Indeed. But it is also worth noting that a balanced input (unless item is fully balanced from in to out) comes at a cost, be it hiss (active) or THD (tformer). If an unbalanced op has extremely low Z, terminated to an unbalanced IP, it may well give better noise performance. Self has written about this, and anyone who has spent time designing with a noise analyser will know for themselves. GML mic preamps have a balanced IP but unbalanced OP for this reason.

Interestingly, although I am a big fan of balancing tonearms, most MC carts have incredibly low Z. This means that, in measurements, I have noticed virtually no difference in noise of the same cart to SUT whether unbalanced or balanced. Were there significant EMI / RFI sources in my room I suppose it could be a different story.

 

[Speedskater]

Electronically balanced inputs have more hiss than unbalanced - fact.

With modern circuit design the added 1.4 dB of hiss remains inaudible. But an unbalanced RCA interconnect system may have 10 to 20 dB's of added Common Impedance Coupling hum & noise.

 

[knobtwiddler]

With modern circuit design the added 1.4 dB of hiss remains inaudible. But an unbalanced RCA interconnect system may have 10 to 20 dB's of added Common Impedance Coupling hum & noise.

Speaking as someone with audio analysers (R+S, AP, Prism etc.) I've yet to measure this hum and noise you're speaking of. Neither has George Massenburg (hence his use of RCA o/ps - on pro equipment, designed for studios). If the output Z is low, in most domestic situations, you will have overal lower 20-20KHz Noise with unbalanced.

 

[DonH56]

Indeed. But it is also worth noting that a balanced input (unless item is fully balanced from in to out) comes at a cost, be it hiss (active) or THD (tformer). If an unbalanced op has extremely low Z, terminated to an unbalanced IP, it may well give better noise performance. Self has written about this, and anyone who has spent time designing with a noise analyser will know for themselves. GML mic preamps have a balanced IP but unbalanced OP for this reason.

Interestingly, although I am a big fan of balancing tonearms, most MC carts have incredibly low Z. This means that, in measurements, I have noticed virtually no difference in noise of the same cart to SUT whether unbalanced or balanced. Were there significant EMI / RFI sources in my room I suppose it could be a different story.

Hiss is relative to the signal levels and gain structure, natch. I think there are two things going on here. Differential circuits by nature improves SNR by 3 dB (signals double, uncorrelated noise RSS's, so signal goes up 6 dB and noise only 3 dB), so comparing an active single-ended circuit to an active differential circuit, the differential (balanced, I realize not always the same thing) circuit will have better SNR. However, comparing an active differential circuit to a single-ended or quasi-balanced circuit where the higher signal level is not used, the single-ended circuit will win.

I suspect what @Speedskater is referencing is the benefit of common-mode rejection that differential circuits provide, that can provide 20 dB or more of common-mode noise rejection and potentially reduce hum by breaking a ground loop. All that is very implementation-dependent (at the circuit level).

I no longer have a TT set up. When I did, I found the same thing as you -- MC cartridges, while may pick up motor hum in a poor design, by and large were less sensitive to noise than the high-Z MM cartridge input stages. Hiss at the speaker varied, however, since the MC carts tended to have lower output and thus required an additional gain stage. Usually any added noise was buried in the noise floor of the recording itself so not noticeable.

IME/IMO - Don

 

[MediumRare]

Better common-mode noise rejection is another reason, especially for long mic runs.

Thanks for reminding me - I've added your quote to my post. Much obliged!

 

[Not Insane]

Hi Guys

This is my first post on this forum. I am just starting my journey in to buying hifi equipment. I tried to search for similar topics already posted in this forum buy couldn't find any so started this one.

I am looking for a DAC to feed in to Luxman 590 AXii. On the basis of my readings on the internet, I am of the view that XLR interconnects have benefits over RCA. I won't be running the interconnects for more than 1 meter. I am holding my decision to buy a DAC only because of output choice from the dac.

If the consensus is that XLR outputs have clear cut performance advantage and clearly noticeable, I would definitely go for a dac with XLR outputs, if not, than I am happy with RCA as well.

Kindly share your opinion on this.

Thanks
Vivek

Having been in a few bands, I deal with XLR a lot. One day I finally decided to get to the bottom of why XLR is used in pro audio so much. I was quite surprised by what I found out.

To whit, XLR is better for long cable runs (common in pro audio). For short runs it is irrelevant.

 

[Speedskater]

Speaking as someone with audio analysers (R+S, AP, Prism etc.) I've yet to measure this hum and noise you're speaking of.

If we look at different audio/hi-fi forums, we can find hundreds of threads about hum, noise and 'ground loop' problems. Experts like Jim Brown, Neil Muncy (RIP), Henry Ott & Bill Whitlock have often written about the problems of unbalanced interconnect systems.
* * * * * * * * * * * *
In the Stereophile magazine, measurement side-bars there are sometimes comments about hum & noise problems in their tests.