I have a question about properly matching my DAC with my amplifier. The setup is as follows:
DAC: dCS Bartók APEX, with selectable output levels 2V or 6V via XLR.
Amplifier: Vitus Audio SIA-030, which allows input sensitivity to be set to 2V, 4V, or 8V for full output.
What would be the optimal combination of DAC output level and amp input sensitivity in this case?
My idea:
6V DAC output → 8V input sensitivity on the Vitus SIA-030
Why this seems like a good match:
It uses the full dynamic range of the DAC, offering more headroom and less chance of digital distortion.
The amplifier won’t be overdriven, avoiding clipping.
The DAC operates in its optimal voltage range, which typically results in lower distortion and noise.
Result: lower noise floor, better resolution, and maximum transparency.
Question: Does this logic hold up? Or are there situations where using a lower DAC output (like 2V), or setting the amplifier sensitivity to 2V or 4V, might be preferable for example, regarding gain structure, usable volume range, or system synergy?
How do you currently control the volume of your system day to day? Do you use the volume control on the Bartók, or do you use the volume control on the SIA-010?
Where do you usually keep this volume control when you are using 6V out of the Bartók and 8V sensitivity on the SIA-010?
At the moment, I’m using a 2V output from the Bartók and a 4V input sensitivity setting on the SIA-030.
The Bartók is set to full output (0dB), but I find that I have to turn the SIA-030 up quite high around -20dB to get a satisfying listening level. While there’s still plenty of headroom, I’m wondering if switching to 6V > 8V might be a better match in terms of gain structure and overall performance.
That indeed is the right question. The SIA-030 has a relay controlled fixed resistor network volume control, so I would use that, and the Bartók on 6V out/ 0.0 dB fixed out, and the Vitus on 8V input sensitivity.
Thanks for your reply. Fixed output on 6V was exactly what I was thinking as well. And yes, the volume control of the SIA-030 uses a relay-controlled fixed resistor network, which is definitely superior.
There’s no technical reason to go one way or another, given the variable output and input voltages of both products - you should try 6V out 8V sensitivity and see how it sounds, and if you prefer it to 2V / 4V. The Bartók has separate circuitry for generating 2V and 6V output levels so one isn’t superior to the other. It may be that the SIA-030 sounds a bit better one way or the other, and it may be that it is happier being driven with 6V. A bit of listening is the best way here, and trust what your ear tells you.
One thing I would also try is listening to whichever voltage option with the SIA-030 at 0dB volume and the Bartók volume control at -20dB (or whatever you find the correct level to be). Digital volume controls are completely free of distortion if you do them correctly (if you have enough control and bits to use, which the Bartók does), and both the Bartók and the Vitus have fixed noise floors hat turning down the volume control lowers the SNR against. 20dB down is 20dB down whichever product you’re using That isn’t intended to spark any analogue vs digital debate by the way, just give you another option to try, as again your ear will be the best judge here.
Thanks for your response. I’ll take some time to listen carefully to both setups and see if I can actually hear a difference and ultimately, which one sounds better to me.
Hi
I have the same vitus sia030 integrated.
The easy answer is dac 6 volts out, vitus 8 volts in, dac set to 0.0.
I have tried a few different ways over the years but, this is the best way.
It’s very dynamic, has a fantastic sound stage, plus the bass control is superb.
The sia030 really is a fantastic bit of kit, enjoy.
Thanks for your response. I’ve now set it up this way, and it will stay like this for the next 200 hours until it’s fully broken in. I received the SIA-030 yesterday after a four-month wait.
I’m already incredibly excited and it can only get better from here. The dynamics and control are truly impressive.
I’ll also try 2V > 4V at some point down the line.
Also you can run the vitus in bypass mode, i haven’t ever got this to work, for some reason.
But it basically bypasses the pre amp in this mode, so it’s kind of like running direct. So maybe something else to try at some point.
But the sia030 is a beast and can easily keep up with most separates.