Totaldac D1-Driver, the (pre)amplifier driver

I am not in the habit of starting threads unless I feel a product is of significant enough importance to do so. The Totaldac D1-Driver is such a product. The official product description states D1-Driver, the amplifier driver. I have deliberately added (pre) in the thread title.

The Totaldac website description reads:

The d1-driver is an analog driver. It is usually connected to the output of the DAC.
It is an answer to the endless question "is it better with or without preamp?".
The strength of preamps is there active stage more than their volume control. The active stage helps driving the power amp.

It was designed for directly driving a power (or integrated amplifier!) using the built in Totaldac digital volume control:

Its drive capability allows the d1-driver to improve the sound of a DAC, improving bass control, articulation, presence, soundstage and life. It has been tested when connected between a DAC and a power amplifier (transistor or tube), but also between a DAC and an integrated amplifier. The d1-driver has no volume control because it relies on the DAC volume control.

Around 6 weeks ago we travelled to Slovenia to deliver a SGM Extreme server to Matej Isak for a review. I ended up leaving being deeply impressed by the liveliness and dynamic range of Matej's reference system. Upon asking Matej told me something about the importance of proper gain matching. I did not give it much further thought until we visited forum member Mike Lavigne a few weeks later where he played a few tape cuts with a similarly shocking display of brute force dynamic range. Every since returning I have been searching for explanations for this particular phenomenon. Until I received a pair of Totaldac D1 drivers from Vincent last Friday.

I need to add a bit of history context to this now as I was not unfamiliar with the D1-driver. I have tested an older version before, the current D1-driver is in its second generation now. At that time I was impressed by its dynamic range and transparency, but found it lacking in refinement and micro detail rendering compared to my AudioNet Stern (Euro 35.000) preamplifier. If I remember correctly my commentary to Vincent was "a diamond in the rough". It also did not manage to match the Stern's sound staging abilities, upon which Vincent commented I would probably need a pair to get there. I shipped it back and did not give it much further thought, therefor the penny did not drop until Vincent told me he had a MK2 version of which he was confident it would solve my "issues" and if I would be interested in trying a pair of them. This turned out to be a totally different ballgame. Not only does it manage to match the Stern's sound staging abilities, refinement and micro detailing, it has also improved upon its previous strengths with even better dynamics, and an "Iron grip" control over the lower registers which sounds like it has doubled the already high damping factor of my AudioNet Heisenberg power amplifiers. It has incredible control and slam, at first I thought it was lacking low end extension, but after some back and forth switching it is just much better defined and controlled turning a mass of "1 tone bass" into a variation of cues and pitches. It does give me the eagerly desired dynamic range I found my system lacking of after hearing Matej's digital and Mike's tape. Therefor I consider it to be a substantial product worthy of its own thread.

Using both the Stern and D1 drivers in a DAC - Driver - Preamp configuration does preserve most of these qualities with just a slight decrease in overall transparency, clarity and a loss of ultimate "control". Inserting the Stern creates a slightly more distant, slightly more laid back perspective, where just the drivers give you a closer more direct perspective.

Matej Isak has reviewed the D1-direct and D1 driver here, worth a close read:

https://www.monoandstereo.com/2019/09/totaldac-d1-direct-d1-seven-d1-driver.html

I will copy a few relevant snippets:








To summarize, this is a product to seriously consider, not just to combine with a Totaldac DAC, and not only to replace a preamplifier. But consider trying it with any brand DAC and/or any Pre-amplifier.

 

David
i am in the UK and use a D1-direct, reclocker and two mono D1 -Drivers.
Mine are RCA unbalanced between the D1-direct and Drivers, but with a balanced out.
Like others I use a passive pre (new Townshend Allegri Reference)
I love the Drivers. It is very natural and musical.
not as Euphoric as my active valve pre and sometimes i still put that in just to have a ‘fun’ moment, but extensive relaxing listening is with the passive.
The Difference the drivers made was that rather than the music being ‘in, or between’ the speakers, with the drivers i could not hear the speakers. The music was more alive and natural.
Vincent helpfully allowed me to listen to a stereo version and dual mono versions. I stuck with the dual mono.

 

Hello,
I use d1-twelve-mk2 -> RCA interconnects -> d1-drivers monoblocs -> Amp-1 amplifier
The gain of the full system is just as needed so I can set the volume to 0dB when playing very loud a very dynamic track.
For music I use the d1-twelve-mk2 DAC volume control.
For cinema and concerts (in the next room) I set the DAC volume to 0dB (max) and I use the video preamp volume control. This preamp is a Marantz in which I have integrated a Totaldac reclocker, so the volume and AES-EBU output is managed by the Totaldac reclocker exclusively.
Details are here http://www.totaldac.com/home-theater-eng.htm

Maybe all this would not be so easy if I used an extra passive preamp I think.

 

thanks for the replies - very helpful.
for those running a passive preamp after the D1-Drivers - what improvements are you hearing from this approach?

anyone choosing not to use d1-drivers with a D1-Direct?

 

Applied two tweaks onto my two xlr version D1-Drivers.

I dont have sufficient rack space at home and have to stack them up.



Run out of CMS CS2 footers too.
Luckily I still have 2 sets of ASI Top Line footers.
https://feature.u-audio.com.tw/featuredetail.asp?featureid=540
I pair them with Yamamoto Pb-10 ebony spike plates.



The whole soundstage now has the veil removed.
Haha

 

Originally the Drivers were given Cerious Tech Graphene Extreme powercords.

This week they are replaced by two Vertere HB powercords.
https://www.vertereacoustics.com/hb-power-cable




Vertere Audio is founded by Mr Touraj Moghaddan who is basically a vinyl/analogue-man.


The cables of Vertere are famous for their musicality, naturalness, continuousness and microdynamics.
They are best paired with low level signal or low current components.
And I am not disappointed this time!

 

Thank you CKKeung,
You left the protection on the font panel window!

 

Thank you CKKeung,
You left the protection on the font panel window!

Hong Kong style!

 

Hong Kong style!

 

Around 6 weeks ago we travelled to Slovenia to deliver a SGM Extreme server to Matej Isak for a review. I ended up leaving being deeply impressed by the liveliness and dynamic range of Matej's reference system. Upon asking Matej told me something about the importance of proper gain matching.

Just for everyone's information, this is not gain matching. It may be level related in a few cases, but it mostly about the impedance and current capability of the driver of the DAC as well as the sensitivity of the amplifier. Current sensitivity, not the typical voltage sensitivity. The lower the impedance of the DAC driver, the better dynamics you will get with many amplifiers. Some tube amps that are very high impedance don't need much current drive from the DAC, but many do.

Most DAC's have about 20-50 ohms output impedance, and some are even higher. Compare this to the typical active preamp, which can be 1 ohm or even fractions of an ohm. If a low impedance is sustained at all frequencies and dynamics, then most amplifiers will be happy and deliver great dynamics. Even though the steady-state impedance of the amp may be 50K ohms, the actual di/dt current required by the amp may be higher in order to accurately reproduce dynamic phrases in the music.

These dynamics can be further impeded if there is a resistive attenuator or a TVC used between the DAC and the amps. The TVC is usually less of an issue than the resistive attenuator.

This creates the need for a buffer between the DAC and the amps that shows a high-impedance to the DAC and delivers a low-impedance with unimpeded dynamic current capability to the amps.

 

@Empirical Audio, indeed, the D1-driver has a gain of 1 (you can get it with higher gain on request).

 

Indeed it is not only the matter of system voltage gain since the d1-driver has a gain of 1.

It is clearly not as simple as the output impedance improvement because adding the d1-driver to a DAC equipped with a discret class A transistor output improves the sound, even if the output impedance is similar for the DAC and the d1-driver. The test has been made with a d1-six for example.

So even in the case where the d1-driver changes neither the signal voltage nor the signal impedance it improves the sound.

 

Indeed it is not only the matter of system voltage gain since the d1-driver has a gain of 1.

It is clearly not as simple as the output impedance improvement because adding the d1-driver to a DAC equipped with a discret class A transistor output improves the sound, even if the output impedance is similar for the DAC and the d1-driver. The test has been made with a d1-six for example.

So even in the case where the d1-driver changes neither the signal voltage nor the signal impedance it improves the sound.

So, how do you dynamically measure the output impedance of these two components across the frequency range?

 

So, how do you dynamically measure the output impedance of these two components across the frequency range?

I have a lab equipment able to measure that, showing the impedance curve for the 20Hz-20KHz range.

 

Running multiple preamps in a chain is standard practice in recording studios. After a while certain combinations gain a reputation for being 'the setup'. The whole 'less is more' perspective is more prevalent in audiophile circles than recording circles...

 

Running multiple preamps in a chain is standard practice in recording studios. After a while certain combinations gain a reputation for being 'the setup'. The whole 'less is more' perspective is more prevalent in audiophile circles than recording circles...

Last month a studio in the USA tried a Totaldac reclocker for his analog mastering, and confirmed that less is more can sometimes be wrong for digital as well. He bought two of these reclockers, for two systems and said he drastically improved his work.

 

Running multiple preamps in a chain is standard practice in recording studios. After a while certain combinations gain a reputation for being 'the setup'. The whole 'less is more' perspective is more prevalent in audiophile circles than recording circles...

That explains why the really good recordings are few and far between.

They generally don't believe in good cables either I have found.

Most of the damage comes from mixing with inferior software, too many analog stages causing compression and sometimes too much jitter. This is why I like the sound of Bluecoast recordings. They mix with analog tape and then digitize. No compression.

 

Re: cables that is true. My former Neumann mastering desk was partially rewired at Columbia with Belden...

Didn't stop London Calling from being a pretty great LP though (not my work...but similar gear)

Even the so called 'holy grail' studio preamps of yesteryear were not technically unusual. Perhaps parts were well graded...

 

..too many analog stages causing compression and sometimes too much jitter...

What is this analog jitter?

 

BTW I observe that Vertere Audio cables are rather underrated in N Am although there are dealers in US & Canada (Rutherford Audio).

What a pity!
They are as good as Vertere's top tonearms and turntables.
Their supreme naturalness & musicality suit not only analogue components but even more so for digital and CAS systems.

Other than the HB powercords, I am using their HB xlr ic, HB ethernet cable & USB cable too.

 

Vertere are absolutely amazing cables. They commanded my respect early on and are expensive. They are on the same level as Steve Nugent's reference cable. I use to purchase them out of the UK without any issue.

I recommend Vertere without reservation.