Digital volume control, WADIA style


Some of the highest ranked CD players and digitall processors let you control playback volume level in digital domain. This feature lets you drive the power amp directly, without the preamplfier connected in the audio chain.
One pair of interconnect cables becomes obsolate as well, which is good - we shurly can all agree here.
What you gain overall is a much shorter and simpler signal path. Good achivment, indeed.

But all this comes at a cost. Do we loose anything?

Yes, we do, and it is due to little recognized manipulations conducted upon the digital data stream. We are begining to play with the digital bits representing our musical signal now. Much like genetics, isn't it?
To what effect? Well, this is the question of this tread.

Some well respected manufacturers, Wadia and dCS to name two most noble of them, encourage their customers to take this digital manipulation road as being clearly superior and less audiable than even the best preamplification (=analog manipulation, let me call it by it's name).

Some others, Theta and Mark Levinson comes to my mind at the time, steer away from digital manipulation.
For those who really need some means to control the volume from within their processors or players they incorporate analog volume control circuitry in some models.

What is your personal expirience?

Is digital volume control much audiable?
Is it better than top class preamplfication?
In which case artifacts introduced to the music are easier to detect and more irritate you?
mrgigi
I have experimented with my Wadia 850 running direct (adjusting the internal switches so that digital attenuation is minimal), and also through a number of preamps including Pass X1, Levinson 380S, ARC LS25, BelCanto Pre1, Art Audio, and others. Frequently the preamp would "modify" the sound in a pleasing direction, e.g., focusing vocals, improving bass definition and macrodynamics (the SS preamps), smoothing out the treble (the tube preamps), and so on. However, every time I came back to the direct Wadia, I was impressed with the "palpability" and realism of the sound, especially on difficult music reproduction like piano. So in the end I've just gone with direct. (The extra interconnect cable required for the preamp no doubt adds some flavor as well.)
Remember that Wadia artificially increases the bits to 21 in the DSP (I can't claim to really understand this), and that every 6dB of reduction on the display corresponds to a loss of one bit. Thus dropping to 70 still leaves you at 16 bits, and thus no net "loss" of information. Of course it is better to stay closer to 100.
When comparing Wadia to other CDPs with analog volume control, such as Res. Audio CD55, Levinson 390S, and Audio Aero Capitol 24/192 (all which I've heard in my system), the differences I hear are IMO largely due to other features of the design besides the output gain control. By the way, these are all great sounding CDP's, but they span the full range of the "organic to technical" spectrum of personal preference. For me, I like the immediacy and harmonic-correctness of the Wadia midrange, even if Wadia can be bettered in other aspects by some players. (I should mention that my 850 was modified by Great Northern Sound; this gives a nice improvement over the stock unit.)
WADIA direct/volume controlled IS better than via a pre in my opinion.
I compared the sound of my WADIA through the pre's of BURMESTER and AR SP14. The effect was different of course, but in both cases the directly connected WADIA kicked - as long as you stay well over 70 in the display reading. I do not know the exact output voltage in this setting but the WADIA is at a comfortable volume around 80 to 85 with all sorts of sources in my system. A friend of mine had the same results with a LAMM pre.....
Good luck!
I believe there is a preferable sonic difference, when the most realistic situation is called for, between even the best passive preamp and the Wadia 8xx or such straight in, in favor of the Wadia to amp connection. The factor arbiting is balanced all the way with fine cables. IMHO.
Does anyone have any experience in using either a placette passive line stage or their stand alone volume control. It seems that with these products, losings bits is a (moot)? point.
I've used an Accuphase DP-75 both straight into power amps, which calls for using at most 12 db of attenuation, usually 6-8 db, and through a very high quality passive preamp, one that's a lot more detailed and transparent than my old CAT SL1 III. There was little in the passive to degrade the signal, but to some extent it did. Anyone could have heard the superiority of the "straight in" approach using the DP-75's digital volume control. Wadia adds a refinement: you can set a level of nondigital attenuation that allows you to use as little as possible of the digital, about 12 db for my CD collection, and I'd bet that's typical. So I agree with the others that digital and no preamp is the way to go.
I've used an Accuphase DP-75 both straight into power amps, which calls for using at most 12 db of attenuation, usually 6-8 db, and through a very high quality passive preamp, one that's a lot more detailed and transparent than my old CAT SL1 III. There was little in the passive and its associated interconnect to degrade the signal, but to some extent it did. Anyone could have heard the superiority of the "straight in" approach using the DP-75's digital volume control. Wadia adds a refinement: you can set a level of nondigital attenuation that allows you to use as little as possible of the digital, about 12 db for my CD collection, and I'd bet that's typical. So I agree with the others that digital and no preamp is the way to go.
I use the dCs Elgar direct into my power amps. I also have the Z-Systems digital preamp in front of an MSB Platinum straight in. I also can use a very high quality Vishay resistor shunt to ground stepped attenuator that I put into my poweramps. With this setup I don't have the variation in sound due to the preamp and extra cables when I do the comparison between digital and analog attenuation to impact the comparison. I've listened carefully to all three and there is no sonic difference due to attenuation in the digital domain with these specific units. Cutting out the preamp and the cables gets you closer to the music with these units no matter how expensive your preamp is. Caveat, this is not generalizable to all units and poweramps.
The nice thing about the Wadia's digital volume control is that you can increase the player's base level output internally so that you never have to go below 70 on the control and lose any bits.
I am using a Wadia 860x directly into my Krell fpb300 via Kimber 1111 balanced. I would have it no other way. when i first hooked up the wadia in my system I was using a krell KRC 3 pre and kimber kctg. from the Wadia to the Pre. I listened to it for a few days before i went direct to the amp with the kctg's and was not expecting the improvement that I got.

I never went back and I am very pleased with the results. I have read quite a few articles saying that you should use a pre and that the bits are dropped if the volume control is below 70. I am sorry but in my case i donot believe any of it. what my ears hear is an improvement without the extra circitry. If you have aneed for additional components ie. tuners tape decks etc. than you do need a pre. If you want the best sound from your primary source go straight in and enjoy the music.
mrgigi: my experience comes from the direct connection of accuphase dp-75 and dp-75v cdp’s. both of these units have high-quality digital attenuators based on the designs of the accuphase all-digital preamps, the dc-300 (which uses the same dac as the dp-75) and the dc-330 (which employs the dac in the dp-75v). both of the one-box cdp's from accuphase sound better in my experience run directly than through a preamp, even one of accuphase's analog models (e.g., the c-290v). there is NO degradation of sound with these digital attenuators; they do NOT "drop bits" or otherwise manipulate the d>a processing. not all cdp's with volume controls can match the accuphases' performance. some do, indeed, drop bits and thus degrade their sonic output. -cfb