Two Volume Controls…

Jamp7

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I am attempting to use the bass management of the Ultra but use the Ultra’s optical out to feed my own DAC. My DAC outputs to my preamp. I believe I am getting what I want except…. My preamp and the Ultra each have a volume control. Unfortunately, with this setup the speakers are being managed by my preamp and the subwoofer is being managed by the Ultra. And of course, The two volume controls adjust the volume at different rates. Should I hook my system up differently to use my DAC with bass management coming from the Ultra? Suggestions? Thank you.
 
I took my preamp out of the mix. I am using my DAC and sending its output directly to my power amp. This is the way I would like it to work. It sounds pretty good, but my preamp does improve the overall sound. Hopefully I can make some adjustements to the sound, because the bass management does work to eliminate resonating bass coming from my speakers. Again I like this simpler connection along with having only one volume control, the one on the streamer.
 
Did you try the Ultra's built-in DAC as well?

Regarding the pre-amp I wonder how it can improve the sound if it's intended to sound neutral and transparent. Is the DAC's output stage powerful enough to cope with the power amp's input impedance? RCA cables?
 
My DAC is a Schiit Modius and my amp is a Schiit VIdar 2. Not well versed in this but I am told it is ok to connect the DAC directly to the amp.
 
You do have the option of leaving the Modius's volume knob at a fixed position and then controlling playback volume with the Ultra's knob. That would leave the Modius in the circuit for whatever improvement in sound quality you're getting. (You'd want to mark or note the position of the Modius' knob in case someone comes along and turns it and you need to reset it to the correct spot.)
 
You do have the option of leaving the Modius's volume knob at a fixed position and then controlling playback volume with the Ultra's knob. That would leave the Modius in the circuit for whatever improvement in sound quality you're getting. (You'd want to mark or note the position of the Modius' knob in case someone comes along and turns it and you need to reset it to the correct spot.)
I understand it's the unnamed separate pre-amp connected after the Shiit Modius that results in better overall sound. The Modius doesn't appear to have a volume knob.

My DAC is a Schiit Modius and my amp is a Schiit VIdar 2. Not well versed in this but I am told it is ok to connect the DAC directly to the amp.
Shiit's website doesn't list a product named Vidar 2, just Vidar or Aegir 2. Probably doesn't make a difference since it's all the same Shiit. If they say it works this way ...

No matter how you put it, if you want to use it's sub out, the you must use the Ultra's volume control and only the Ultra's volume control. Any other devices down the chair must be set to fixed volume prior to setting the correct subwoofer level.
 
I have been all over the place on this trying different configurations. So far, I believe, the best overall sound for me is to use optical out from the Ultra to my own DAC. My DAC outputs to my preamp and to my headphone amp. I set the Ultra volume control at about 75% and control the volume with my preamp or my headphone amp.
 
I have been all over the place on this trying different configurations. So far, I believe, the best overall sound for me is to use optical out from the Ultra to my own DAC. My DAC outputs to my preamp and to my headphone amp. I set the Ultra volume control at about 75% and control the volume with my preamp or my headphone amp.
If you are not going to use the Ultra's volume control anyway, setting a fixed output volume (100%) is the theoretical optimum.

If you feel the usable range of your pre-amps pot is limited, you could reduce the Ultra's output volume.
 
If you feel the usable range of your pre-amps pot is limited, you could reduce the Ultra's output volume.
In the app you have options to set the line level output to 2 volts, 1 volt, 800 mV, 500 mV or 200 mV. When using the fixed output level choose the one that is the best match for your setup. IMO, that would be the output level that allows the volume control on your preamp or integrated amp to be at around half to three-quarters up when listening to your music at your preferred maximum volume. Analog volume controls track between channels most accurately in the upper half of their range. And, the settings just recommended leave you a little more room to boost the volume if you come across a recording that was made at a softer level.
 
Analog volume controls track between channels most accurately in the upper half of their range. And, the settings just recommended leave you a little more room to boost the volume if you come across a recording that was made at a softer level.
It depends a lot on the quality of your pre-amp, of course. E.g. my trustworthy old Quad 34 shows pretty much no channel imbalance at all down to maximum attenuation.

In any case, bass management cannot be used when the volume is not controlled by the Ultra. I would really double check what benefits the overall sound quality more.
 
I’m kinda surprise how well passive volume work but it’s inconvenient that I have to get up to adjust volume depending how dynamic the music. There’s many possible combination you can do on ultra. From what seeing here if you want to use sub you need to set external dac to fix and ultra does the adjustment and works both optical and coax.
 
For my latest, I am still using optical out from the Ultra into my DAC. My DAC outputs directly to my power amp and directly to my headphone amp. My DAC does not have volume control so when I am listening through speakers, I only have one volume control, the Ultra. When I listen through headphones, I have two volume controls so I set the Ultra volume control at about %80 and use the headphone amp volume control to control volume. This setup eliminates the preamp from the system which is kind of sad, but the sound is the best so far.
 
I also have mine setup for fixed output and connected to my Anthem I225 Integrated, Sub Out connected directly to my JL Audio powered sub.

What we all really need is a preamp with 3 inputs: Left Channel, Right Channel, and Subwoofer IN, and then Subwoofer Output ( without bass management as that is already done by the WiiM Ultra ).

So the preamp then controls the volume for the L+R+S.

Unfortunately, no such preamp exists that I can find, so request to Wiim to create such a preamp (or add-on? ) with analog pot ( Alps? ) that's remote enabled, and maybe a tubed version to boot? :-)

They owe us since they created this dilemna ha ha ha ha

Would also solve where you want to use outboard DAC. The DAC L+R would go into the preamp, Wiim Sub Out goes into the preamp Sub In. Presto, preamp controls the volume of the DAC and the Subwoofer.
 
Imagine an interesting new product: Two sets of analog inputs (when I say sets, I mean each set has single-ended and also balanced), one volume attenuator that controls output synchronously BY WAY OF TWO SETS OF SYNCHRONIZED RESISTOR LADDERS (analog-domain attenuation, not digital) between the two sets of inputs, and then matched sets of outputs (again, both, single-ended and balanced). The entire device should be active, so that if you use single-ended input, it can still output a balanced, differential signal after the volume control, and on the output end there should be an option to combine L/R signals into a single signal (like an LFE output).

And even better yet, we should allow adjustable high-pass filter on the first set of in/outputs and an adjustable low-pass filter on the second set of in/outputs. Slope and frequency should both be adjustable. And of course both filters can be bypassed.

The unit should also have a single 12V trigger input and three 12V trigger outputs, and it should have a remote control that can control volume, filter slopes and filter frequencies.

We can call this...Ed's System Matrix.

-Ed
 
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All volume controls worsens the sound. The one in WiiM ultra is one of the better sounding ones, with no SRC .

For the WiiM ultra , using the digital volumecontrol from digital out to a dac, the sound is best when the volume is between 30 - 100.
If the volume is higher than 30, its impossible to hear any worsening of the sound from the digital volumecontrol in the WiiM ultra.

A separate analog preamp is not a better sounding option than driving the poweramp directly from your dac, controlled by the WiiM ultra ( if the output impedance from the dac are below 400 Ohms and the power amps input impedance is higher than 20 K. )

If you have a power amp with to much gain, you may have to use the digital volumecontrol at 15-30 at most time. It will still sound good, but is not ideal.

The solution is to lower the gain of the power amp . You can do this in a number of ways.

1. If you know something about electronics, you can desolder the gain resistor near the input opamp inside the power amp, so it will become unity gain. Lowering the gain from the very common 27 dB in total, to maybe 15 dB can be audible better. With this trick the digital volume control in the Ultra can be set at a higher level , above 30 . Many Hypex ncore can do this mod, I did it for my ncore and the sound became better.
This is the best way to lower the gain, soundvice.

2. You can use inline RCA attenuators. Those are however never transparent to the sound.

3. You can solder a voltage divider for each L/R channel using good resistors inside the amplifier , directly at the RCA input. This sounds better than any switched attenuator or passive volumecontrol.

A good value is : 10K for each channels in series at + input, after that two resistors at 2K from + from each channel to the common ground for the two channels.

I used 4 dale resistors to do this in my tpa 3255 amplifier building, and the sound was clearly better with more detail than using my former Monacor inline RCA attenuator. The Monacor uses the same resistor values but are of worse quality than dale and not soldered. You can hear this.
 
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