Single Ended DAC vs Dual Differential XLR DAC

short answer is 'not always', or 'it depends'

in a theoretical world all other things other than the variable you highlight (dual opposed dac chips vs single) are equal

in the real world they are never equal

GIven twice the number of DAC chips in the dual differential DAC then the likelihood is it will sound better because the signal-to-noise ratio (SNR) will be higher than with a single DAC per channel. How much better though is dependent on the implementation details.

Basically what ^^^^ they said.

I don't know if you're talking about single ended (RCA) or XLR or a dual mono dac as opposed to a shared signal path and transformer.

RCA vs XLR is never certain XLR on paper should sound better but that is not always the case. Very cable dependent too.

Dual mono is usually but not always superior it's always better to listen and decide for yourself.

Thanks for your replies!

@lordmelton , I'm not referring to dual mono. The Single Ended RCA DAC I'm considering is the MHDT Pagoda ( http://www.mhdtlab.com/Pagoda.htm ) and the dual differential XLR DAC is its brother MHDT Balanced Pagoda ( http://www.mhdtlab.com/Pagoda%20balanced.htm ).

The Balanced Pagoda simply has 2x PCM1704 DAC's per channel in order to obtain the negative and positive portions of the XLR signal while the unbalanced Pagoda simply has 1x PCM1704 per channel for just the positive signal.

Now that I'm playing with an open hand...do you think the Balanced Pagoda to be superior to the Pagoda? Or the dual DAC for the negative and positive portions of the XLR signal could decrease signal accuracy? I think about tolerances that make a chip never identical to another leading to a slightly "smeared" signal.

It's the old story of single ended RCA considered simpler and someway better than XLR by someone while others say exactly the opposite.

Eventually, I own an RCA Pagoda, should I take a Balanced Pagoda with no chance to test it before buying?

Thank you for your help!

Gianluca

Member Teajay did a review of the balanced Pagoda for Stereo Times that would provide some valuable insights for you.  Best of luck. 

@gkg2k Hi Gianluca I feel your pain not being able to demo gear, however as I see it the single ended dac is $1.5k and the balanced $2.5k. I would definitely go for the single ended and spend the extra $1k on good cables but DEMO the cables first, don't just buy them because they are expensive.

Otherwise loads of Chinese R2R DACs available around $2-3k.

Hope this helps. 

Great choice,  here's some info to help you decide which you need.

Pagoda Top Dac

audiosciencereview.com is full of retards that can barely scrape 50 bucks together for a headphone amp. Total wankers that just measure the resistance of cables. I've said enough.

@soix Thank you very much for directing me to the Teajay review of the Balanced Pagoda that's the heart of my mental devices these days! He claims the Balanced Pagoda is magic precisely because it's balanced that way and the RCA outputs don't sound equally well. The RCA outputs of the Balanced Pagoda should be comparable to an unbalanced Pagoda. It's a great indication, thank you!

@lordmelton I've listened to the Sonnet Morpheus MK2 R2R DAC that's one of the best regarded XLR DAC's today and I think it has monster resolution but it largely misses the magic (again!) of the BurrBrown PCM1704 + buffer output tube of the MHDT Pagoda. I've just listened to the unbalanced Pagoda. You're perfectly right about good cables!

At present I'm moving towards the Balanced Pagoda thanks to Teajay's rave review...

Gianluca

@lordmelton 

audiosciencereview.com is full of retards that can barely scrape 50 bucks together for a headphone amp. Total wankers that just measure the resistance of cables. I've said enough.

haha, +100 

could not have said it any better...

I often like a lot what Amirm of audiosciencereview.com REJECTS in his tests 😄 It's happening again in spectacular fashion for the Pagoda! He'd throw it in the trash (and I'll buy it)

Gianluca

This hobby would suck if I didn’t trust my ears enough and to the point where I had to rely on measurements to tell me what’s good or not.  Sad.  Truly sad.  I look at measurements too, but Jeez. 

I don't see what beef people have with ASR or Amir. I think he's doing a great service for the community measuring all this gear.

If you like gear with crappy measurements, so be it. The conclusions / recommendations are his opinion so you're free to reject it.

Personally, I like to buy products that are well engineered *and* sound good. Usually if you have the former, then you've got a good chance for the latter.

I've had my Pagoda for about 3 years and out of curiosity I read the "review" and subsequent posts on ASR. What's fascinates me about Amir and ASR in general is the lack of actual listening to the product he's measuring. I know Amir took a hit for this a couple of years ago but it seems not much has changed in that regard. 13 pages of bashing a DAC none of them have heard nor will ever hear because of SINAD (it's the worst in ASR history!). OK, bad measurements according to Amir, but how does is sound? Apparently it doesn't matter and the acolytes are all over the forums trying to save us from ourselves yet again. Joy.

What's fascinates me about Amir and ASR in general is the lack of actual listening to the product he's measuring. 

BINGO!!!  In his world, measurements trump listening.  He can’t trust his own ears and let’s measurements dictate what must sound good.  Measurements are important, but they’re not everything.  

@yage

I don’t see what beef people have with ASR or Amir. I think he’s doing a great service for the community measuring all this gear.

For me it’s the off balance approach. I much prefer a review process which includes measurements and listening. Stereophile’s review of the Border Patrol DAC comes to mind:

https://www.stereophile.com/content/borderpatrol-digital-analogue-converter-se

It seems Amir’s/ASR’s take-down attitude has become sport. I just don’t understand why. What’s the point of the vitriol regularly spewed over there? We’re all aware a bad review can hurt a small manufacturer in a very big way. Is the goal to put them out of business? I can’t imagine doing this to anyone.

If a product peaks my interest, I want to hear it for myself regardless of measurements. If I don’t like it I send it back. I don’t have a problem saying something wasn’t for me but I’m certainly not going to talk trash all over the internet. But what do I know? I’m just a delusional old fool.

@gkg2k .. apologies for veering off course. If you decide to take a chance on the balanced version I hope you'll share your impressions (warts and all). 

A couple of years ago there was a long and heated discussion in DIYaudio about this topic (maybe it's still going on). Generally speaking higher SNR  means in the digital domain more bits which would translate into more resolution. The position from the developer (Soekris) was that the Soekris DAC would deliver 26bits of resolution (calculating it from the number of used resistors per channel in the R2R) while the other party insisted that the SNR numbers simply wouldn't verify this claim.

So whatever is true we can say at least that XLR has higher SNR compared to SE DAC.

My personal experience is that it also depends a lot on how one connects the DAC to the rest of the system and what source files (bit depth) are being used. Especially considering digital vs. analog volume control or a mix of both (like what I am doing). Because if one uses a 16bit signal and digital volume control one will listen in the end to  maybe 12bits of resolution only. Can still sound satisfying with the rest of the system and room acoustics and one wouldn't even notice. With 24 bit signal depth and a 26 bit DAC (like the Soekris claims) it works as long as the input sensitivity of the power amp and the sensitivity of the speakers are in range with the necessary digital volume settings for comfortable listening.

A combination of digital and analog volume control  make it easier to fine tune without losing resolution and allows better adjustment to the rest of the system in my experience.

The biggest flaw of analog volume control  is that it takes some part of the signal and connects it to ground (voltage divider principle) and a lot of transients and subtle elements of the signal get lost first. The lower the settings the more is dumped to ground. A combo of digital and analog allows the best compromise between bit depth and transients. It's clearly audible, at least in my system.

So XLR or SE considering  SNR, bit depth, and volume control  is the chain that would need to be looked at in order to find the correct answer.

@melvinjames ,

Measurements, done correctly, do not lie. Perhaps if manufacturers took their own measurements and published them, as opposed to others doing it, then sites like ASR would not even exist. As a consumer, I feel like manufacturers are taking advantage of us. When I started into audio in my teens in the 80's, ever speaker vendors with few exceptions posted response curves. Today that would be the exception. There is not desire on the part of manufacturers to educate their customers in general or even on their own products. We are expected to believe everything in their marketing blurbs. While I tend to find Amir's tone often arrogant, bordering on offensive, I do appreciate the work and other similar efforts as it levels the playing field between consumers and manufacturers.

I believe that most audio purchases are made with relatively little prior listening, and are based on reading reviews. Many of those reviews are highly suspect and involve little in the way of critical listening or critical comparison. Based on those reviews perhaps you buy this product, and you like it, but the noise background seems a bit high, and it sounds "good" but perhaps not quite right. So you come to a site like this, and people tell you, well you need to:

• buy this or that expensive interconnect
• buy a $500 power cord to make it really shine
• buy a $1000 reclocker if you want better performance

Now, another $2,000 in, not knowing any better, you still think it sounds "off".

It sounds "off" because it IS off. And none of those glowing review sites told you that, and no one here told you that, they told you to spend more painting the pig.

Measurements, done correctly, do not lie.

Nor do they the whole story.

I believe that most audio purchases are made with relatively little prior listening, and are based on reading reviews. Many of those reviews are highly suspect and involve little in the way of critical listening or critical comparison.

Agree with this big time and is a HUGE pet peeve of mine. TAS is a main offender of not doing any relevant comparisons or even disclosing what equipment is in the review system and I’d never rely on one of their “reviews” to form an opinion on a product. However, there are some good, rigorous reviewers out there who I find very helpful, so it’s important to find the more reputable reviewers out there and just ignore the trash.

You will get a better s/n ratio and a cleaner, clearer signal with a fully balanced unit.  That being said, if you do not have a fully balanced system, it is unlikely that you will get the full benefit of this.  This is largely due to the fact that at some point, the balanced signal will be converted to a single ended signal when it hits the unbalanced component.  Common mode noise rejection is lost and the quality of that transformer will have a BIG impact on sound.  

That transformer is often why, single ended devices sound better when using RCAs rather than XLRs with a transformed signal.  It is also why balanced devices XLRs almost always sound better than the RCAs that typically accompany the units.

If your system is fully balanced, you should get a fully balanced DAC.  SE will never sound as good.  If your system is single ended, a fully balanced unit will sound as good as a single ended unit at best.  Pay a lot of attention to the quality of the output of the RCAs if you get a fully balanced DAC.  Brands like Bricasti and Weiss have virtually no difference in performance between XLRs and and RCAs in practical terms but those are more the exception than the rule.  Many others see signal degradation in that XLR to RCA transformer.  

The reason the circuit is duplicated, (4 chips vs. 2 chips, etc...) is driven by the need to produce the inverse for common mode noise rejection.  That extra chip does not increase resolution, etc...

@verdantaudio ,

The reason the circuit is duplicated, (4 chips vs. 2 chips, etc...) is driven by the need to produce the inverse for common mode noise rejection.  That extra chip does not increase resolution, etc...

While that may be true in this device, where the noise is so high that nothing will fix it, using two DACs in a balanced configuration will often result in an improvement in THD+N/SNR as non-linearity is averaged between the two chips.

I think you need to explain more about the transformer you mention. I assume you mean an external transformer based single ended to balanced converter?

Unfortunately, there is no guarantee that balanced will sound better. It all comes down to the implementation as you have noted, and it takes more components and it is harder to do properly than a single ended connection. You are pretty much always guaranteed to get better noise/emi rejection, but I would be cautious about that blanket statement w.r.t. distortion.

You are right...being sloppy. If all you are doing to convert an SE signal to XLR is adding an "inverting amplifier" you will not get all the benefits of a device being "balanced" and depending on the quality of that section of the amp/premap/DAC, etc... you may get degradation in quality. This is where you can get the phenomenon of RCAs sounding better than XLRs in non-balanced equipment.

If the entire circuit is fully balanced, then it will be cleaner sounding but if the components that balanced signal is being sent to are not balanced then all that excellence is lost.

In practice, this shows up in DACs. Take the Rockna Wavedream SE vs. XLR. In a fully balanced system, the XLR DAC will outperform the SE. In an SE system, the XLR and SE will sound the same.

@verdantaudio ,

I think you are interchanging balanced and differential but perhaps do not mean to. "Balanced" would refer only to the connection. Differential would refer to the circuitry.

The single most important reply is by abraxalito.