[running wild]

I have a Lavardin integrated, with 10Kohm input impedance. Normally these impedance issues are only sensible between preamp and amp, not between source and preamp/integrated, because you are always in the KOhm area. Maybe hearing via headphones amplify the issue ?
Nevertheless I have tried to find what is the output impedance of the DAC1 ref: Nowhere to be found....
Can you perhaps ask them ?
EDIT: The "usual" relation is to have at least a factor 10 between output and imput impedance. This would mean that the Lab12 has an output impedance of >1KOhm to be a problem for a 10KOhm imput impedance amplifier ?. This is rather unusual for a DAC to have such impedance....= To be checked

My SPL has 20k and the Flux has 10k input impedance.
I will ask them.

 

[running wild]

@Lucus
My seller has a Leben tube amp which has 50k input impedance. With this he has had no problems.

 

[Lucus]

What surprise me is that an impedance mismatch shows normally in the bandwidth ( less bass) rather than distortion

 

[running wild]

I asked Lab12 about the output impedance but have no reply yet.

 

[Lucus]

I have received an answer from Lab12: Output impedance is between 1 and 1.5 KOhm
It is high, but should not be a problem for a 10Kohm input impedance I think...

 

[running wild]

@Lucus
I got also a reply from Lab12

„Regarding your question we would like to inform you that the output impedance of DAC1 Reference is about 1Kohm. Both outputs are parallel since DAC1 Reference tube output stage is designed single-ended topology.“

Strange that I have these issues with it.
I will try my last amp tomorrow and if there is the same problem i will try to sell it or send for inspection to the Distributor in Germany.

 

[Lucus]

I will receive mine next week, so I can report if it is working fine with a 10KOhm amplifier
Are you using both output (RCA+XLR) of the Dac at the same time on 2 different amplifier ?

 

[running wild]

Are you using both output (RCA+XLR) of the Dac at the same time on 2 different amplifier ?

I have connected it only with XLR. I used this with the Gustard.
Then i tried RCA only with the same results.
I have only one Amp connected and switched to the Flux Labs instead of the SPL.

I will receive mine next week, so I can report if it is working fine with a 10KOhm amplifier

Yes, please.
This will be very helpfull.
Thank you.

 

[running wild]

I´ve done my last tests for the moment.
Connecting the DAC1 to my SAC Pre and the SAC La Forzas and my Markaudio 10 speakers.
As source the Auralic Aries G2.1
I got the same problems with the distortions. Not that strong noticable as with the SPL and HP, but there.

The next step was connectin the DAC1 to the Questyle CMA 15 in my working room.
As source i take my Macbook Pro with Audirvana Origin running the same library as the Aries.
The CMA 15 was my HPA to the Rognir - same problematic distortion as with the SPL or Flux.
I don´t know how much is the input impedance of the CMA 15.
What........

 

[Lucus]

Can you try to describe the "distortion" sound ? As said, the problem in impedance matching reflects normally in limited bandwith, esp. in limited (very) lows and (very) highs....not in "distortion". It is like having a high pass and low pass filters
I fear there is a problem with your DAC

 

[running wild]

Can you try to describe the "distortion" sound ? As said, the problem in impedance matching reflects normally in limited bandwith, esp. in limited (very) lows and (very) highs....not in "distortion". It is like having a high pass and low pass filters
I fear there is a problem with your DAC

You make me curious about that.
I found an article where this is described as you said with the limitation of the bandwith.
I think that is what i call "distortion".
It sounds "unclean" - not as expected.
Like you increase the volume of an amp to the maximum and the speaker can not work with that ......

I hope your DAC will come soon so we have a comparison

 

[running wild]

The Gustard X26 Pro has an output impedance of 100 Ohm.
The Ferrum Wandla has 22 ohm unbalanced or 44 Ohm balanced.

Let´s see how the DAC1 works with your amp.

 

[Lucus]

After 48hrs stabilization/warm up, hearing cession since morning: So far so good, the DAC is not the most neutral I've heard, but the slight medium/highs overtone is not disturbing. Nice soundstage, airy and deep, fine details: Good basis for future improvements (NOS tubes, cables, fuse...)
Sofar no distortion nor problems....

 

[running wild]

Hi,
nice to hear your DAC has arrieved and you are happy with it at the moment.
So it seems that mine is defective
What music do you listen to?
What source do you use?

 

[Swann36]

After 48hrs stabilization/warm up, hearing cession since morning: So far so good, the DAC is not the most neutral I've heard, but the slight medium/highs overtone is not disturbing. Nice soundstage, airy and deep, fine details: Good basis for future improvements (NOS tubes, cables, fuse...)
Sofar no distortion or problems....

Hoping you’ll give some updates as it’s burns in