To preamp or not to preamp

[August (August H)]

I would use 6V and more attenuation on the volume control. Too much gain is not good and will cause distortion in the next gainstage. By going direct this is not very likely because there are less gainstages in your amplification chain.

[Simon2]

But I read from this forum that the recommemded dCS attenuation level is from 0~-30db due to the digital/ analogue signal to noise ratio?

[August (August H)]

@AndrewS

You don’t have to worry about a bit of attenuation, the dCS volume control is implemented after oversampling so doesn’t start ”throwing away bits” until about -40dB.

Please see what volume setting you need on average by using 6V output.If it is -40dB or higher, it should be fine.

[AndrewS (Andrew)]

Sorry, I misremembered, it should be -30dB, not -40dB.

[Donald_D]

I think I can answer my own question. Output gain is controlled at the analog stage before the signal reaches the output whereas digital volume control happens at the digital stage immediately before the signal is sent to the Ring DAC.

[AndrewS (Andrew)]

@Simon2

Which is better? And how can I know if the amp is over driven? (Which output voltage drives the amp more??

• The one that sounds better to your ears is the one that’s better. My previous post was a proposed workflow not a prescription.
• You know that the input is being overdriven when it stops sounding good and suddenly starts sounding strange/bad. Almost all electronic components/circuits have a point at which their performance becomes non-linear. Usually the effects are not subtle.
• In my very personal opinion the gradual reduction in bit depth (DR) associated with exceeding -30dB in attenuation is inconsequential compared with the 9.54dB gain in SNR from moving up one increment in output voltage. I would urge you to trust your ears and not look at the level of digital attenuation.

[Urbanluthier]

I run my Bartok 6V direct into a Benchmark AHB2 and listen -20 to -6dB depending on the recording. Very dynamic sounding!

[Donald_D]

That’s the most encouraging post in the whole thread. I’m starting to be optimistic that the preamp can be avoided.

[RobW (Rob)]

Depending on desired noise level (always staying well below -30) I simply switch between 2V and 6V to run my Audio Research Ref. 160S direct. I even sold my AR Ref6 SE

[Urbanluthier]

@Urbanluthier

I run my Bartok 6V direct into a Benchmark AHB2 and listen -20 to -6dB depending on the recording. Very dynamic sounding!

I should have also added that, I listen midfield at moderate levels with 86dB efficient speakers. I have the AHB2 set to the lowest gain so even 6V will not drive the amp to its 100w rated power. I simply don’t need a lot of power in my room with my speakers. I’m almost alwasy at the top end of the volume. With really hot recordings I’ll do what @RobW noted and drop down to 2V.

I used a highly-regarded ‘Class A’ reviewed pre amp previously. I had no idea how much the pre was adding, until I took it out.

[Simon2]

@AndrewS

In my very personal opinion the gradual reduction in bit depth (DR) associated with exceeding -30dB in attenuation is inconsequential compared with the 9.54dB gain in SNR from moving up one increment in output voltage. I would urge you to trust your ears and not look at the level of digital attenuation

After all, in your opinion 6V out with -35db is preferable to 2V out with -25db theoratically. Is it correct? (Subject to my listening evaluation coming first)
Alse 6V out drives the amp less than 2V out even the listening volume is the same? (Subject to the both not producing a distorted sound)

[AndrewS (Andrew)]

@Simon2

After all, in your opinion 6V out with -35db is preferable to 2V out with -25db theoratically. Is it correct? (Subject to my listening evaluation coming first)

Exactly, subject to that working with you particular amp/speaker combo you will have a lot more signal and a lot less noise.

Alse 6V out drives the amp less than 2V out even the listening volume is the same? (Subject to the both not producing a distorted sound)

No, 6V drives the amp more than twice as hard as 2V, that is why system matching is an important caveat. But again, subject to it working with your amp and speakers, I predict it will give you a better sound than 2V, even though 2V allows you to run with 9.5dB less attenuation.

Apologies if this is still not clear Simon, I feel I have simply run out of ways to say it.

[Simon2]

Now everything is crystal clear about the output voltage and attenuation of dCS dac.
As I am using dCS also as a preamp connecting directly to poweramps, I will be safe in the system matching if the preamp of the poweramp brand has a more output volage than 6 volts of dCS
In balance connection, before the cilpping
-Mastersound preamps have the output voltage of 10~15 volts,

• In case of Pass xp-22 preamp, it is 32 volts.

Therefore I will be properly driving poweramps of two brands with 6 volt output of dCS

Thank you Andrew

[Simon2]

I also now set the output voltages of two dCS at 6 volts.
Passx600.8 is rated at 600w and the other Mastersound 845 is at 50w.
A bit concerned with 845, but with its 2 huge transformers it will be fine. I will see…

[Donald_D]

I want to share the insights we gained from today’s audition. First, the ZERO iTRON active speakers that can be seen in black (the horns belong to the Avantgarde Acoustic Duo speakers behind them) are a lot more compact than what they appear in some pictures and they are really not that expensive at 23,560 € for the pair considering that one doesn’t need a power amp. The Lina can drive them and they sound good at low volume but they didn’t wow me. Both, Andrew and James in another thread, are right, there is no need to get a preamp for volume control. 6V out and digital volume control on the dCS DAC works perfectly fine. The Rossini APEX, however, drives the ZERO iTRON speakers more effortlessly, a lot more effortlessly, and there is definitely a wow effect with the Rossini at low volume. If one is looking for amazing low volume listening with these speakers, it’s at least the Rossini, I’d say. The dealer has had his Rossini APEX demo unit on offer for 19,900 € even before I had requested the audition and he will sell me the Rossini demo clock at basically the price of a new Lina clock which makes going for the Rossini over the Lina easy. I’m super happy because the Rossini APEX elevates these speakers for listening at low volume to another level.

Now to the preamp and the bitter pill (financially). As I mentioned before, we used the WestministerLab Quest and when we plugged it in, the dealer and I immediately heard better delineation of the instruments and a deeper sound stage while the dCS sound was preserved. There was no coloration of the music whatsoever. This effect works particularly well for low volume listening with these speakers. With more high-end speakers this preamp may not be necessary but in this combination it’s a must, I’d say. The WestminsterLab Quest adds exactly what Angie Lisi describes starting at around 13:04 in this video. I’ve gained a lot of respect for her after today’s listening session.

We also used Roon to stream music BTW because my MacBook stopped working with either of the dCS DACs at some point for some strange reason. It works perfectly fine now with my Lina at home.

One more point on the bass of the speakers, it can basically be shut off by the volume buttons on the back so it won’t be an issue.

The most important component in your HIFI system? Angie, 40 years of experience reveals the secret!

[AndrewS (Andrew)]

Thanks for the feedback Donald! IMO you have asked all the right questions, solicited everyone’s opinions, got the best advice (including my own), listened, and reached a conclusion that is right for you.

Hat off to you . This is a lesson for everyone who buys blind on the basis of online reviews or forums. You know you have made the right choice. I wish you many hours of happy listening!

Regards….andrew

[Merlot52 (David)]

Hi Andrew

I was on the phone today to Phil H. Haven’t spoken to him since 2011, during his Salisbury days.

I have read 99% of this thread and found it really interesting, and found roughly 50/50 using, not using a pre. Some, quite rightly suggesting that the choice is a personal one, and depends what your set up is.

I am a novice and got a bit lost reading the last dozen or so posts, regarding voltage, volume and gain.
I have a full Naim set up.
NDX 2, XPS DR, NAC 282 (pre amp) Supercap DR, NAP 300 DR + 300 PSU.
My plan is to replace the Naim NDX 2 and XPS DR with the Bartók Apex, (non headphone amp).
Phil indicated that the Bartók would be more than happy without the Naim 282 pre.

At the end of the day, all our ears are different and it is for me to demo in my home and listen to the A-B comparison.
Regards
David

[AndrewS (Andrew)]

Hi David,

There are a whole bunch of folks here who have owned Naim gear and I am sure they will be happy to share their experiences. But as you say all our systems are different and all our ears are different.

Here is a thread that may provide some food for thought, or help lead you to other forum members who may be able to offer advice or answer questions.

Naim Convert to dCS

So I may be taking the plunge into a Bartok or Rossini. I currently have a Naim system (552/recent DR upgrade on the PS), 300 DR. I got into streaming this summer with an ND5XS2 with an ndac fed by a 555PS. I thought I’d eventually get to an ND555 which was perhaps my move now but have been reading a lot about dCS. I’ll do more reading but given the trades I have, perhaps the Rossini could be the better fit. I don’t have the extra funds for the clock at the moment but like the idea of a futu…

Good luck!

Regards….andrew

[Phil (Phil Harris)]

@Merlot52

@Merlot52

I was on the phone today to Phil H. Haven’t spoken to him since 2011, during his Salisbury days.

It was a lovely chat too … it was nice to catch up with you again!

Phil

[JPSPOCK]

Nice discussion. I had a Puccini, than the Rossini and finally version apex. I tried them all directly to my Pass Xa, and compared with different preamp like Pass xp20, arc ref5se, and my actual passive preamp Bespoke audio. Each time, I had to come back to my preamp. Preamp create the scene, plan are different and deeper, give more presence… it’s not tomorrow I will not use anymore a preamp. Would have been interesting, so I should have gone to the Vivaldi.