I bought a Creek OBH-12 which are (understandably given the simplicity) by all accounts super transparent, with the idea that you run the DAC at max volume, use the Creek to turn the volume down to your maximum normal listening level, and just leave it alone from there and use the DAC controls.
Does anyone have experience with the WestminsterLab Quest preamp and would a preamp, assuming itâs as neutral as possible, make a difference for listening at low volume?
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At the risk of exposing my ignorance, digital volume control inside the dCS DAC means choosing between 0.2V, 0.6V, 2V, and 6V output?
No (although of course changing the gain setting will affect the volume level). James is referring to the digital volume control that is built into all our DACs, controlled by the rotary knob (B/R/V) or the shortcut buttons that are enabled if you unlock the volume control (in Device Settings) on a LINA 2.0, or for all units via Mosaic or an IR remote.
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Hi @AndrewS, just confirming: third party apps like Roon are also directly accessing the DACâs digital volume control, correct?
I know that Roon does. I donât want to write a blank cheque but I suspect that others like Spotify and Tidal work in a similar way. @James?
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To add to Andrewâs comments, most of the Streaming software apps have a volume ânormalisationâ feature which aims to level the volume between different tracks/albums. You must disable that if youâre wishing to get bit-perfect transport from these Apps and use dCSâ native volume control.
Additionally, Roon and a number of others (like Audirvana) have Digital Signal Processing capability to either up/down sample or apply speaker/room correction as well, which also needs to be disabled if you want bit-transparency.
Itâs not uncommon for one or more settings to be left enabled by default which generally causes people to perceive sonic differences between Apps, when if totally bit-transparent, there should be no difference other than personal subjective biases having an impact 
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Thanks for this reminder @Anupc.
I have all of the DSP functions in Roon turned off, for obvious reasons, except one: auto down-sampling of DSD256 to DSD128 so that the Rossini can play these files (thank you again @Bauer).
I will recheck my Roon volume settingsâŚ
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DSP processing is necessay, not evil, and you have no way to avoid it no matter how âpureâ you want to play your music. Nearly all published music had gone through some sort matering process which consists of many specific steps of processing.
Only few people listen to ârawâ or âpureâ music/sound recorded by your phone/mike untouched but that is hardly publishable.
Hi.
Weâre talking about the DSP within the signal processing chain, post production. Let me clarify my comment:
To me, it makes zero sense to purchase a $30,000 DAC like the dCS Rossini and then use the DSP of a $2,000 software program like Roon to do the processing, unless one is absolutely forced to, as dCS users currently are with all DSD formats greater than 128.
Cheers,
R
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Not so. Although older dCS units cannot process DSD files with sampling rates in excess of DSD128 you can now buy Varese which will do the job .
No doubt more units in the future will feature updated streamer boards too.
: )
Pete, you are correct. I somehow forgot about that $200,000+ option⌠; )
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Since I cannot post to the âdCS Lina DAC in a 2-channel systemâ thread (have three posts in a row) here are the plans for this weekend to explore some of the discussion points mentioned here and in a couple of other threads (my interest is the Lina with these active speakers).
The audition will be the Lina DAC directly connected to the ZERO iTRON speakers and the Lina DAC via the WestminsterLab Quest preamp to the speakers. The XLR cables will be 0.5m and 2m Cardas Clear Beyond in order to keep the interconnects variable constant. The dealer also has a Rossini APAX demo unit that we will hopefully try.
It will be interesting to hear whether 6V output from the Lina with volume control from the preamp makes a difference for listening at low volume with these speakers rather than going direct with digital volume control from the Lina and, IF the preamp makes for a subjectively (psychoacousticly) more pleasing listening experience, how will going from the Rossini APAX directly to these speakers differ.
The ideal situation for me financially and aesthetically (I prefer a minimalistic setup) would be that the Lina connected directly to the ZERO iTRON speakers with the Cardas Clear Beyond cables will be so good at low volume that neither the preamp nor the Rossini APEX make a significant difference. At higher volume and in an acoustically optimized room (which I donât have) there will likely be a discernible difference with the Rossini APAX but thatâs not what I will be looking for.
Look forward to hearing your findings, Donald.
Just one point to bear in mind. I have been travelling this week and have visited a number of our dealers. Many of them have our equipment set up in their âhigh endâ room and many of those have vinyl and digital sources so use preamps. Of course all of them should also be happy to hook up a dCS DAC directly to a power amp on request for a âhot rodâ digital-only system.
As I have written on several occasions 6V out is my clear preference all else being equal. The difference in signal level between 0.2/0.6/2/6V is 9.54dB for every hop, so given that the noise is more-or-less constant there is nearly 40dB of SNR improvement from lowest to highest. That is HUGE.
But everything is not always equal! What I am finding in the field (entirely anecdotally) is that 6V is much more likely to overload the input stage on a preamp than on a power amp (possibly makes sense given that the majority of preamps contain an additional active gain stage). So an apples-to-apples comparison becomes a bit problematic. At 2V The SNR will be lower and the system will sound a bit duller and less vital but at 6V the preamp may be overdriven potentially ruling out this option.
My recommendation is therefore to try 6V into the pre and see if it works but donât be surprised if you have to back down to 2V (in rare cases lower). But almost certainly use 6V for direct-to-power. This means you will have to level-match with an SPL meter to ensure that you are actually comparing at the same volume level.
My point is that when comparing with/without pre it probably makes more sense to compare apples-to-pears (the highest output level into pre and power respectively even if they are different) than the seemingly âfairerâ apples-to-apples approach of running the same output level into both. The former shows both options at their respective best whereas the latter will likely be compromised in one or the other configuration.
I believe most of the preamps through which I have heard dCS gear this week are excellent, highly resolving and largely transparent devices and have realised that when I have felt they make the system sound worse it is almost certainly because they have forced me to drop to 2V, and not because of any deficiency in the preamp itself.
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Thanks for the Advice, Andrew. Weâll go 6V from the Lina directly to the speakers. I have installed an SPL meter app on my phone. My hope is that the XLR cables weâll use in combination with this iTRON technology of the speakers will make the preamp totally unnecessary.
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To clarify your reply, when connecting dCS directly to the power amp which setup sounds best?
- 0.6V out w/-10db
- 2V out w/-20db
- 6V out w/-30db
Iâd like to add one question, what is the difference technically between lowering the gain vs. lowering the volume digitally?
What I am saying is use the highest output level that doesnât over-drive your amp. You donât have to worry about a bit of attenuation, the dCS volume control is implemented after oversampling so doesnât start âthrowing away bitsâ until about -40dB.
BTW, for most power amp/speaker combos I am guessing 0.2/0.6V wonât even be an option. In practice those setting will only make sense for active pre-amps.
Well, I have two sets of monoblock poweramps;
One is Rossini apex ->PassX600.8 â YG Sonja 2.2i where 0.6V out gives me -8db atteniation and 2V out -18db.
Which is better? And how can I know if the amp is over driven? (Which output voltage drives the amp more?)
The other is Bartok apex->Mastersound 845 (50W/channel) ->YG Vantage 3 where I use 2V out with -12db. Here again on the point of the noise level and properly driving the amp, would you recommend using higher or lower voltage?