Wadia S7i direct to amp

11-27-10: Egidius
@paperw8 have you tried what you are explaining?
It's just, the statement by krellfan might not be wholly unexptected, if the pre substitutes something otherwise missing.

if your question is: have i driven a wadia directly into a power amplifier? the answer is yes.

if your question is: have i driven a wadia s7i directly into a power amplifier? the answer is no, because i have a wadia 381 [i will leave it to the reader to determine how much difference that should make].

if your question is: have i modified the output voltage delivered by the wadia by flipping internal DIP switches? the answer is no because when i drive the wadia directly into the power amplifier i almost never set the output level of the wadia at 100%. generally i set the output level in the 65% to 85% range depending on the recording level of the source material.

to be more specific, i drive the balanced outputs directly into the power amplifier and i drive the single-ended inputs to a preamplifier. i primarily tend to drive the wadia through a preamplifier when i want to listen late at night. i live in a residential area, so i can't blast music late at night. when i use a preamplifier i set the output level of the wadia at 100% and vary the output volume at the preamplifier. the reason why i do this is because the sound tends to become thin when you turn the digital output level at the wadia too low (as i described earlier).

but as i stated, ultimately all of this stuff is a matter of preference. if it sounds better to you when you drive the wadia into a preamplifier, then you should drive the preamplifier from the output of the wadia. but what i am telling you is that when you do that, you aren't getting greater "transparancy"; instead, what you are getting is the sound produced by the wadia after it has been colored by the electronics in the preamplifier: that is the "something otherwise missing" to which you are referring.

I own a Wadia S7i, and I have ekspermitteret with preamps with my S7i.

The conclusion was very clear. There is a HUGE difference between preamps, and there is also no doubt about, that a good preamp does it _much_ better than the digital preamp built into the Wadia S7i. For those who may doubt my conclusion, try using a Classé Omega MK III, Tidel Preos or Viola Cadenza.

The cost for a good preamp is definitely worth the price, compared to the improvement of the sound.

11-28-10: Chris10an
I own a Wadia S7i, and I have ekspermitteret with preamps with my S7i.

The conclusion was very clear. There is a HUGE difference between preamps, and there is also no doubt about, that a good preamp does it _much_ better than the digital preamp built into the Wadia S7i. For those who may doubt my conclusion, try using a Classé Omega MK III, Tidel Preos or Viola Cadenza.

i don't question that the wadia s7i sounds better to you when going through a preamplifier. but to make this point clear, you *always* go through the digital preamplifier with a wadia; there is no digital preamp bypass. in your case, the output of the wadia digital preamplifer drives the input of your preamplifier; and then your preamplifier drives your power amplifier.

..thanks for your clarification! Good to know there is background behind a statement ;-)
I cannot judge 381 vs s7i, they will have similar problems.
Interesting point about the Digital pre - but:
isn't it always the case with a DAC giving out the full power (i.e. 100%),
or you mean to say, they could make a purist version without attenuation sounding - pure?
My technical background is too small to judge this..

11-28-10: Egidius
..thanks for your clarification! Good to know there is background behind a statement ;-)
I cannot judge 381 vs s7i, they will have similar problems.
Interesting point about the Digital pre - but:
isn't it always the case with a DAC giving out the full power (i.e. 100%),
or you mean to say, they could make a purist version without attenuation sounding - pure?

i think your question is could wadia make a cd player that had both fixed outputs and variable outputs. while you do see that feature in some cd players with integrated preamplifiers, it is unnecessary for wadia to offer such a feature. the reason is that the wadia preamplifier operates in the digital domain.

the way that the wadia preamplifier operates, it attenuates signal volume digitally when the output level is less than 100 but does not attenuate the signal when the output level is 100. it is only after the digital signal level is determined that the a/d is performed and an analog voltage delivered on the analog outputs. so if you don't want signal attenuation, set the output level to 100 on the wadia. this unattenuated signal is equivalent to a "fixed" output that you might see on some other units. when you send the output from the wadia to the preamplifier, you should set the wadia output level at 100 and then control the volume level (in the analog domain) at the preamplifier.

of course this unattentuated signal is not actually a "fixed" signal because you can vary the output. but since the varying is done in the digital domain you don't have the situation that you would have if the attenuation were done in the analog domain. in that case, you would perform the a/d conversion first to generate an unattenuated signal. this analog signal would be in the analog domain. one copy of the unattenuated signal would go to "fixed" output terminals. another copy of the unattenuated signal would go to preamplifier circuitry that would allow you to control the attenuated signal level, also in the analog domain. the signal output from the preamplifier circuitry would go to variable output terminals.

the point that i am trying to get across is that since wadia does preamplification in the digital domain, you don't need 2 sets of outputs. since the wadia does preamplification in the digital domain, if you set the digital preamplifier level to 100, then you are sending an unattenuated signal to the a/d circuit. thus, analog output from the a/d circuit is like the "fixed" output. however, if you set the digital preamplifier level to less than 100, then the wadia attenuates the signal in the digital domain. it is the attenuated digital signal that is sent to the same a/d circuit. the a/d circuit then outputs an attenuated analog output signal. but to the a/d circuit, there is no difference, it just receives a digital signal and converts it. the a/d circuit does not have to know whether it has or has not been attenuated in the digital domain.

however, where it can make a difference is that you can lose resolution through the process or digital attenuation. the source material from a redbook cd has 16 bits of digital resolution. the wadia operates with 21 bits of digital resolution. you lose about 0.5dB of volume with each step in the digital preamplifier control. thus, you can drop the digital preamplifier output level to about 65 (from 100) before you are prone to begin losing resolution in your digital signal. as you start losing resolution the signal can start to sound "thin".

where it can also make a difference is when the signal output from the wadia is not loud enough. in that case you can adjust the maximum output signal level. the maximum output signal level from the wadia is over 4vrms. a 4vrms signal level may not drive a power amplifier into clipping, but it is pretty close, so you are probably not going to have any need to supply a voltage higher than that to a power amplifier even if you use a preamplifier.

based on the discussion i have read here, even if you set the digital preamplifier output level to 100 (i.e. output an unattenuated signal from the wadia) there are some for whom the signal sounds better if it is passed through a preamplifier before it is sent to the power amplifier. if that is your experience as well, then you should send the output signal from the wadia into a preamplifier. that happens to not be my experience, so i prefer to drive the power amplifier directly from the wadia. i go through a preamplifier only if i want to play music at low volumes (where i am concerned about loss of signal resolution) or in cases where i need to use the preamplifier to get additional signal gain (beyond that which i can realize by driving the wadia directly into the power amplifier).

if anyone is interested in learning more about the principles of wadia operation there are several white papers on the wadia website.