About tube DACs?

[cotdt]

Originally Posted by Julf

As I wrote, adding harmonics is simply done with a non-linear transform. No fancy processing needed, any DSP can do it. The guitar fuzz/distortion pedal is the simplest example. The effect of output impedance is mostly a simple frequency deviation, but depending on your speaker, the effect of a lower damping factor can be analyzed and replicated - again, the DSP part is not demanding.

Sure, I can program that. But what product on the market can the OP buy that does this? Are you going with the example of the guitar pedal because no such product actually exists for hifi?

The effect of output impedance does more than just alter the frequency response, there is a time component too. However, it is a bit complicated to analyze exactly what the effect is.

[Gyuri]

For me, this is the Tube Dac still now:
http://www.quadesl.com/dac.html

[Julf]

Originally Posted by cotdt

But what product on the market can the OP buy that does this?

And here I was thinking this was DIYaudio.com...

Are you going with the example of the guitar pedal because no such product actually exists for hifi?

There are of course a bunch of units for studio use, but these days most people would use the DSP capabilities in their music player software...

[Gyuri]

I do not believe this, already more, than ten of his years.

[cotdt]

Originally Posted by Gyuri

For me, this is the Tube Dac still now:
http://www.quadesl.com/dac.html

6DJ8 SRPP after passive I/V seems the most common and I agree it sounds good.

[AlliumPorrum]

Originally Posted by cotdt

My point is, if the people here would rather argue about the OP's desire to use tubes in the DAC, then they should propose a better solution. They propose DSP instead of tubes. If that's viable solution, then good. If not, then why question the OP's desire to have tubes in his DAC? Just to feel superior because they themselves prefer opamps that measure better?

This is also a bit off-topic, but I personally really don't have anything against DSP's, just the opposite. DEQX is coming to town quite soon :=) And once again, one important point for this is to minimize the amount of transistors and other analog components from signal path. No analog pre-amp, no analog volume control, no analog crossovers -> less distortion and coloration. On my opinion, every analog component will more or less add coloration to the signal, and everything that happens in digital domain is a better choice (when done correctly, naturally).

But I just can't understand what DSP has to do with DAC & tubes?? My idea surely is not to ADD some coloration or harmonics or anything to the signal. My goal is exactly the opposite; to remove all possible points where the signal is changed or colored somehow. And to my ears, tube based components often mess up the sound way less than solid state ones. I don't know why, and I don't even care a bit. This is just my experience during the 20 years of audio hobby, and dozens of tested devices.

I also understand well if someone thinks just the opposite; well built solid state devices can be really good, but they just are not for my taste. In fact, I also think that person's music taste has a big effect on this. When listening pop/rock or any other electronic music, it is quite hard to say which system is "good" or "better than the other", since I don't know how it "should" sound. When does it sound "natural"??

But when listening acoustic music with saxophones and pianos and (familiar) female voices, it is quite easy to say if those instruments sound realistic or not. Assuming of course, that you have been able to hear those instruments enough on a live situation, so you have something to compare with. In my opinion, female voice is one of the most difficult "instruments" to present live-like from a hifi setup. One of my favorite test CD's is from my friend´s a cappella group, and since I have heard it many many times on a stage (without any amplifiers, of course), I have quite a good "image" of the live sound in my mind. And this is where most of the solid state devices fail; presenting a cappella group so that it really feels live-like.

[DougL]

I have a recommendation:
The K&K Audio RAKK DAC.
I have the Version 1 with the Passive (Transformer) output and love it.

They also have a tube output that looks interesting.

http://www.kandkaudio.com/digitalaudio.html

On a technical note, any tube DAC that use a 12AX7 as a cathode follower uses it to color the sound. I think that tubes can be used that way, but are also very linear if used correctly. I am a big fan of tubes when used correctly. Tubes are one solution. Certainly not the only solution.

Doug

[AlliumPorrum]

Originally Posted by DougL

I have a recommendation:
The K&K Audio RAKK DAC.
I have the Version 1 with the Passive (Transformer) output and love it.

They also have a tube output that looks interesting.

K & K Audio - Lundahl Transformers, audio DIY kits and more

Thanks for the suggestion Doug, I'll surely take a closer look on this!

[cotdt]

I know... but you must forgive us because we like to discuss and argue things.

[Julf]

Originally Posted by AlliumPorrum

This is also a bit off-topic, but I personally really don't have anything against DSP's, just the opposite. DEQX is coming to town quite soon :=) And once again, one important point for this is to minimize the amount of transistors and other analog components from signal path. No analog pre-amp, no analog volume control, no analog crossovers -> less distortion and coloration. On my opinion, every analog component will more or less add coloration to the signal, and everything that happens in digital domain is a better choice (when done correctly, naturally).

I agree.

But I just can't understand what DSP has to do with DAC & tubes??

I also understand well if someone thinks just the opposite; well built solid state devices can be really good, but they just are not for my taste.

I am sure you also can see how somebody who thinks the opposite to you, and thinks your taste is for the colouring most tube stages tend to introduce (and unless you do both proper measurements and true double-blind ABX there is no way to know), would think that DSP is a good way to introduce that colouring in a controllable way...