dCS Vivaldi DAC — Buffer ON or OFF? Does It Affect Sound Quality?

Audio Systems
1

Hi everyone,

I’d like to ask the dCS owners here about the Buffer setting on the Vivaldi DAC — ON or OFF.

I’m still learning about the Vivaldi, and I would really appreciate hearing from anyone who has experience with this setting, particularly whether it has any meaningful effect on sound quality.

Here is what happened when I first received my Vivaldi.

My system was connected as follows:

Zidoo UHD 8000 → Trinnov Altitude 32 → AES/EBU → dCS Vivaldi DAC → Boulder 1160 → B&W 801 D4 (Front Left & Right)

The moment I connected the Vivaldi into my system, I had a major lip-sync problem. The picture was significantly ahead of the sound.

I spent most of the day trying to find the cause. I checked the player, the Trinnov and the Vivaldi, but I simply couldn’t figure out what was happening.

Eventually, I contacted my Trinnov dealer. The next morning, he came back to me with a suggestion that had apparently come from James Cook at dCS.

He suggested that I try switching the Vivaldi Buffer OFF, effectively putting it into a more direct signal path.

And suddenly — everything was perfect.

The lip-sync problem disappeared completely.

What was even more interesting was that I had absolutely no desire to remove the Vivaldi from my system. The improvement in sound quality was so significant that I simply couldn’t go back.

I’m roughly 50% music and 50% movies, so that evening I ended up watching several films just to experience what the Vivaldi was doing to the front channels.

For example, Top Gun: Maverick sounded absolutely incredible. The fighter jets, missiles and explosions had an incredibly realistic sense of scale and impact.

And then I watched The Greatest Showman, a film I have seen many times before. I suddenly noticed things I had never really appreciated in the same way — the vocals, the musical detail, and even the sound of the dancers’ shoes hitting the floor sounded incredibly real.

It was one of those moments where you realise that a piece of equipment has genuinely changed the way you experience something you thought you already knew very well.

But here is where my confusion starts.

When I listen to music through Qobuz, I need to turn the Buffer ON.

When I use the system for AV / movies, I need to turn the Buffer OFF in order to maintain correct lip-sync.

So I now have two different settings depending on what I am doing.

My questions for the dCS owners:

1. What exactly does the Vivaldi Buffer do?

2. How significant is the difference between Buffer ON and OFF from a sound-quality perspective?

3. Does the Buffer actually change the sound, or is its main purpose related to timing, buffering and digital processing?

4. If you have compared Buffer ON and OFF critically, what differences did you hear?

For example, does one setting affect:

  • Soundstage
  • Timing and rhythm
  • Vocal focus
  • Tonal richness
  • Detail and transparency
  • Bass weight
  • Musicality
  • Naturalness or smoothness

I’m particularly interested because I seem to need Buffer ON for Qobuz music and Buffer OFF for AV, and I would really like to understand what is actually happening inside the Vivaldi.

I’d also be very interested to hear from anyone who has used a Vivaldi + Upsampler / Upsampler Plus, as I’m currently looking for a second-hand Upsampler Plus and hope to add one to my system soon.

Thanks in advance to everyone who can shed some light on this. I’m still learning about the dCS architecture, so please forgive me if I have misunderstood something obvious!

I’d really appreciate hearing from experienced dCS owners about their experience with Buffer ON vs OFF.

2

Martin, the dCS manuals generally have a wealth of information in them, so I’d definitely recommend starting with that.

Specifically on the Buffer setting, it’s part of the digital data flow pipeline and does not affect the sound quality,

dCS Vivaldi Buffer
dCS Vivaldi Buffer1318×409 76 KB

1 Like
3

Thank you very much for your advice, I really appreciate it.

I completely understand what you mean. It’s just that, knowing the factory default setting is ON, I still feel a little uneasy about leaving it switched OFF permanently. Maybe it’s just me being a little too cautious! :grinning_face_with_smiling_eyes:

I’m not suggesting that the Buffer setting necessarily changes the sound quality. I’m simply curious as to why dCS has it ON as the default, and whether there is any particular reason or benefit to leaving it that way.

That’s really why I wanted to ask the more experienced dCS owners here. I’d love to hear how others normally use the setting and whether they have any experience with ON versus OFF.

Thanks again for taking the time to share your thoughts — it’s very helpful for someone relatively new to dCS like me.

4

With the Buffer Off, any bit-rate change in the incoming synchronous data stream could cause audible glitches.

5

I understand it much better now — thank you!

It seems that dCS had already made this quite clear from the beginning: Buffer OFF for watching movies and Buffer ON for listening to music.

I think my only problem was that I was being a little lazy! :grinning_face_with_smiling_eyes: I was hoping I could just leave it on one setting and forget about switching it back and forth.

But now that I understand the reason behind it, it all makes much more sense. I really appreciate you taking the time to explain it and share your experience with me. It’s been very helpful!

1 Like
6

Hi Martin, in my setup - Vivaldi Upsampler and Dac I too enjoy about 50% visual. In my case via a Sky box connected via Toslink / optical. The Sky source is quite low quality and it’s clear they have focussed very much on the HDMI interface, Toslink being a secondary output. As such I get ‘timing’ errors if I watch anything live on Sky, these go if I record and playback. Although you have a different source I would also point out that with Sky at least, transitions from programme to advert or channel switching can produce some extremely distressing clicks and pops as well as very different volume levels. My buffer is on, the Vivaldi dac handles well most of the issues. I know these occur though as I have a different dac connected to the same Sky box for TV use and there is no buffering on this as far as I know. Only once have I had serious lip sync issues and that was fixed by a complete Sky reboot.

7

Hi Marty

First of all, thank you very much for sharing your experience, Your feedback is really helpful.

Those clicks and pops can be absolutely terrifying! I’m only just beginning to realise how serious they can sound — sometimes I even feel like the driver is going to jump out of the speaker! :joy:

In my case, I actually have the Buffer OFF when watching movies, and then I turn it ON when listening to music. I noticed quite clearly that when I switched the Buffer, those little pops and clicks appeared, which honestly gave me a bit of a fright at first!

Since then, every time I finish listening to music or watching a movie, I tend to switch the system off completely. When I turn everything back on again, I have to go through the Buffer ON/OFF setting again depending on whether I’m watching a movie or listening to music.

It’s a little bit of a hassle, but after hearing your experience, I’m starting to understand why dCS designed the Buffer function this way.

8

I unfortunately have had two sets of speakers destroyed by electrical malfunctions. The first a set of Khama with ceramic drivers. I owned a Krell amp, borrowed a s/h matching pre and decided to try the proprietary Cast connection. I decided to move one of the cables slightly of the floor at ‘bam’ followed by a tinkling sound of glass. That was the ceramic drivers in bits. Secondly a set of wonderful Magico Q1 coupled with a contemporary hi end amp of repute . A regular crackle sound was evident- it got worse, and without much more than a small volume increase both drivers were gone. The UK distributor did help but it still cost, they took the amp back and suffice to say I’d never go back to this ‘esteemed’ brand. It’s a point that’s most of us have separate components from multiple mnfcs - this blame is always some other part of your system. So far for the past 10 years mine has been safely stable - dCS, Pass, and the replacement power amp from Accuphase. I always turn volume down or mute now before source or programme change. With respect to dCS and Roon, ive never experienced an issue of pops or otherwise- I note the Scarlatti predecessor to Vivaldi wasn’t as good at ironing out such issues.

1 Like
9

I doubt that changing the buffer setting will cause pops and clicks. It may appear to you that is what is happening but it is in fact a coincidence. I am guessing that you are connecting the dCS unit to different sources when listening to music or video . Can I guess that your video source is connected optically e.g. Tosllink with your music source using some other interface? if so then this is a well known issue with Toslink but is not caused by the dCS unit. Let me know and I will explain further and what you need to do to stop it.

10

Hi Pete

Thank you very much for your explanation.

Just to clarify my system connection, my video source is not connected to the Vivaldi via Toslink.

My current signal chain is:

Zidoo UHD 8000 → HDMI → Trinnov Altitude 32 → AES/EBU → dCS Vivaldi DAC → Nordost Odin 2 XLR → Boulder 1160 → B&W 801 D4.

So both my movie and video audio are processed through the Trinnov, and then sent to the Vivaldi via AES/EBU.

Regarding the pops/clicks, I actually only experienced this once.

When I first got the unit back, it was playing music at the time, and I switched the Buffer from OFF to ON. I heard one click/pop at that moment. Since then, I realised that it is probably better to change the Buffer setting when there is no active audio source or playback, and I have been doing it that way. I have not experienced the click/pop again.

So I may have initially assumed that changing the Buffer setting was causing the problem simply because the two events happened at exactly the same time.

There is also something else I would really like to understand. If I simply leave the Vivaldi Buffer permanently OFF, for both movies and music, would I actually lose anything in terms of sound quality, performance, or any other function when listening to music?

I know the recommended approach seems to be Buffer OFF for video and ON for music, but I am wondering whether leaving it OFF all the time would have any meaningful disadvantage.

Thank you again for taking the time to help me. I really appreciate your advice and would like to understand exactly how the Buffer works in my particular setup.

11

Hi Marty

Yes, absolutely. Thank you very much for the reminder and for sharing your experience with me.

I have to admit that sometimes I can be quite impulsive and careless, especially when I get excited about changing or trying different things in my system.

For example, when changing speaker cables or signal cables, there have been times when I completely forgot to switch the system off first, and I ended up hearing those little pops and cracks from the speakers. Thankfully, nothing was damaged.

This time I was careless again. Normally, I am actually quite careful about following the correct power-up and power-down sequence for my system, and I do make an effort to follow it properly.

Your experience is a very good reminder for me that, with a system at this level, it is always better to slow down, mute or turn the volume down, and make sure everything is safe before changing any connection or setting.

Thank you again for sharing your experience. I really appreciate the advice from someone who has been through these situations before.

12

If I’m not mistaken, both your Zidoo and the Trinnov have global Lip-Sync adjustment capabilities for precisely these sorts of issues. Why not leave your dCS Buffer ON permanently, while compensating for the lip-sync issue on your Source or Processor instead?

As already explained, having the Buffer ON or OFF has no inherent sonic penalty within the dCS itself. However, the impact of having the buffer ON is as outlined in the dCS Manual, and consequentially what might happen if it’s OFF;

The delay gives the DAC time to detect changes in sample rate or clock frequency and mute before the change causes audible clicks or other noises.

13

Hi Anupc

Thank you very much for the detailed explanation. I think I finally understand it completely now.

It also makes much more sense to me why the Buffer setting matters differently for movies and music.

For the Zidoo UHD 8000, I can try adjusting the video timing to bring the picture back in line with the sound, but to be honest, I feel that doing it this way is almost like trying to compensate for the problem rather than properly solving it.

As for the Trinnov, I think I will need to wait until I have my next full calibration done. I would rather have the whole system properly measured and calibrated again, including the timing and delays, rather than keep trying to adjust things myself.

For that, I will definitely need a professional calibrator who really understands Trinnov.

Thank you again for your patience and for explaining this so clearly. I have learned a lot from this discussion.

14

Actually, to be pedantic, the Buffer setting only matters when there’s expected variations in the synchronous input source bit-rate or clock-frequency. In which case having the Buffer OFF could result in audible clicks or other noises.

It has nothing to do with Movies vs. Music.

Even when listening to music, through any synchronous input (like S/PDIF or TOSLink), if listening to say a playlist of various bit-rates or frequency, with the Buffer Off, there could be audible clicks or noises.