Tube DACs


For some time I've assumed that tube DACS are meant for direct output to power amps -- in other words, no reason to use a tube DAC if you are running through a tube preamp (unless all components are by same mfr and designed for synergy).

But lately I have seen posts implying some run Brand A tube DAC through brand B tube preamp -- say, Primal Luna 100 to Rogue RP-9. Can't find any prior threads addressing this topic directly.

So, question: am I wrong to suppose that pairing random tube DAC A with random tube preamp B is a bad, or at least a silly idea, absent a known synergy?
 


S

 

hickamore

I recently upgraded to a Nagra Tube Dac and Power Supply and have that running into my ARC Ref6se and ARC Ref160S.  Spent about 1 year searching and demoing different both SS and tube and this is where I landed. Ironically, I switched from a Roon Nucleus + to a NUC and have am using a  Lumin as a stream in between my NUC and my Nagra.  The Lumin adds better sound quality , in my opinion, than streaming with the Nucleus +.

Let us know how you make out.

 

 


I have been using my Ayon Stealth Xs DAC for just over two years now. The sound still blows me away every time I listen to it. It uses 4 6N6P output tubes and 4 tubes in the voltage regulator section. I have their CD II Transport which is also fantastic but now I mostly stream. This DAC showed me redbook CD has a lot more to offer than I ever thought possible. I used to mostly play vinyl but now I mostly listen to digital. This DAC wrings detail and resolution out of CDs that I had no idea was even there- that this level of detail down in the lowest quietest passages just did not exist on CDs. I had a Ref CD player before and I thought it sounded natural but I still would only listen to one CD typically before switching to vinyl. Now I listen to digital for hours.

The Ayon DAC can be used direct to Amp. It has switches on the back that change the output gain hi/lo and a direct amp setting that insures the volume will be near minimum when the DAC is powered on. In non preamp mode the volume control is bypassed. I use bal connectors and I route the music through an ARC Ref 5SE to a pair of Pass Labs monos. I prefer using a preamp between the DAC and amps. I have tried the DAC connected directly to the amp. The sound is different. I found I preferred the sound better going through my preamp. It might be a coloration and most likely it’s just because that is the sound I am used to. It is also for convenience since I listen to vinyl too. The only downside to direct to amp is that the noise floor is slightly elevated. Through the preamp everything is dead quiet- even standing by the speakers. But when connected direct I could just hear a bit of tube noise from my listening chair. Not a big deal but it is there. The Ayon manual addresses it. The manual states that when using the DAC direct some tube noise is apparent because the DAC has no negative feedback and uses large, low resistance capacitors in the output stage. They added that the DAC can be modified to reduce the tube noise but at the cost of a slight performance reduction. The manual states that the tubes should last 8000 hours, as I recall.  I put about 1300 hours/year on it based on my preamp hour meter.

I have a picture of the DAC’s innards on my system page. It is beautifully made as can be seen in the picture. Their next DAC model up uses 6H30 output tubes. I have not heard that version. The 6N6P version however is definitely a winner.

As pointed out already, there’s not much random in your counselling others, and experimenting, to find a combination that allows you to hear deep into your music. I echo the finding of Ayon eqpt. noted in post above.

If you have a tube transport / DAC AND power amp capability / sound character that you value highly, you might try eliminating the relative complication and noise of a pre-amp in favour of a transformer volume control (TVC) or similar device: if you like your upstream components, your music could be revealed much more transparently and richly, depending, of course, upon a positive mating of your components. Enjoy your search.

I don’t think there’s anything wrong with running a tube dac through a tube pre, unless the point is there’s no need to do that, because you you already get tube sound through the pre.  I agree that there’s synergy in coupling tube components together. In my case, in my vintage system I run a jolida tube dac thru a McIntosh MX110z, mated with 2 McIntosh MC30s. 

@smoorenc - yeah, I have an older Line Magnetic, LM502ca - really a wonderful piece and once you get the Chinese tubes out of it and toss in some "better" 12au7 or 5814A (Telefunken, Amperex, RCA clear tops, etc.) it really becomes shockingly good. I run tubes in my Linestage & Power Amp and sometimes it's a bit less dynamic than I'd prefer but for 99% of my listening its a glorious DAC & setup. All modest components compared to many on this site but, synergy between the gear in my main rack is fabulous.