tubes and analog


I just "upgraded" from a Mac SS integrated to a Prima luna dialogue 2 tube amp. The reason that I changed amps was that i assumed that the tube amp would be a better match for my Zu Druid speakers. The amp change was a big improvment for listening through my CDP....but not so when listening to my Rega P9. I had to switch to my spare SS phono stage (Graham slee) to get it to sound right. I was using a tube phono (AES) with my Mac. In Short, my tube amp with SS phono stage is not really an upgrade from my Mac with Tube phono stage. My question is.....should i consider a further upgrade to a better tube phono pre or is it simply that a change from SS to Tube amp is more "pronounced" in digital playback?
csmithbarc
The big advantage tubes have over solid state is that they are *far* more linear. Their gain characteristic is many times better than a transistor or integrated circuit. They also overload in a much more sonically benign fashion, tending towards compression rather than clipping.

Most solid state amplification employs feedback (and lots of it) to cure the nonlinear gain ills. The closest you can get to a tube is by using JFETs open loop. They're pretty good, but still not in the same league as tubes.

On the other hand, most tube circuits require coupling caps. There is, as several of you have pointed out, no perfect design, and they all exhibit artful compromise.

But as Atmasphere points out, the micro details and very small signal information is better recovered via tubes. This is not just opinion, but a technical limitation of topology. The exception would be an open-loop class A gain stage using a reasonably linear active device such as a JFET.

jh
Dear Atmasphere: I apologize for my earlier comment which an American friend explained to me was worded incorrectly. When I said, “I know very well your units but I would not exhibit any of your products”

what I really meant was that I know your units very well, and are not mentioning them (or any other products) as an example to debate. My view is that we can’t generalize that ALL tubes or ALL ss sound a certain way, and that the individual design of the component makes all the differences.

Regards and enjoy the music.
Raul.
Csmithbarc, nothing is off topic, its your thread!! I will say this, there is no definate answer to your recording consistency problem.. However I will give you this, I have had worse sounding recordings on LP back with less serious Phono stage and Cartridge just not compete well with better recordings.. In all honesty Yes once I made a move to a good MC cart and Tube phono stage many of the differences dissapeared and became shockingly excellent sounding original recordings..

But as with everthing, other issues changed along with this, such as putting an expensive cart on the table needed much more attention to setup, and loading with the Phono amp etc.. Which were just more flexable than using a Straight MM cart… Also the excellent recordings are Still just as good and actually far better as well, but all the lesser recordings with a sweet stylus digging deeper are much more detailed and smooth.. So you could be very happy, but it costs more money and more time to get familure with setting up and tweaking your system to your sound, you just need the tools to do it…

And really just ask yourself is all this worth it to me? Or am I pretty happy with CD and not ready to worry about it in the long run? Also for these recordings your not finding too stellar, if you have not invested in a serious LP cleaner and solutions that would be a huge start to find more out of your collection.. Again I am not an expert, but an enthusiast and I have just found in my experience these levels do exist and can be obtained, even without spending a Ton of money but it will cost some cash with no doubt.     
Hi Opus111, of course I do have a 'vested' interest, but I also stand behind what I say, IOW I try to practice what I preach FWIW. I hope that's OK :)

Rauliruegas, thanks for your explanation! No worries :)

I think Hagtech stated the matter better than I could. And I agree with him that if you are going to make a solid state phono section that does detail retrieval correctly, it will have to be some sort of zero feedback topology using FET style transistors. They are the only devices (I know of) that have linearity like that of triodes.

I for one would love to not have to work with tubes. High voltages, filament circuits, the production of tubes and the like all make transistors desirable. But so far I have yet in the 45 some odd years since they really started to appear to see them actually bring home the bacon. If they did, there would not be more tube equipment manufacturers here in the US then there was 50 years ago! The market has spoken very clearly to that.
Dear Hagtech: First my apology to Csmithbarc for this post but IMHO it is extremely important to speak about:

+++++ " The big advantage tubes have over solid state is that they are *far* more linear. " +++++

Yes, I agree with that in normal designs: in our design we develop a totally new mathematics theorem to make the transistor full linear, so that advantage dissapear.

+++++ " They also overload in a much more sonically benign fashion, tending towards compression rather than clipping. " +++++

I agree too in normal designs and in the past SS ones ( even on those times M.Levinson and Mcinthos introduce in their electronics designs a " soft clipping " stage. ). Today almost all SS designs take care about designing with very high overload levels so the clipping subject it is not an issue.

+++++ " Most solid state amplification employs feedback ... " +++++

No, more and more SS designs come with NON feedback design, as a fact the non-feedback design is the SS rule today.

+++++ " But as Atmasphere points out, the micro details and very small signal information is better recovered via tubes. This is not just opinion, but a technical limitation of topology. The exception would be an open-loop class A gain stage " +++++

It is untrue that there is a technical limitation topology, it is not: what could exist is a not so good design but there are a lot of right SS designs out there.
As a fact you state that there is an exeption: " The exception would be an open-loop class A gain stage ... " well this is one of the exeptions.

As you can see there is no single advantage from the tubes against SS, what exist is different designs ( good and bad ) in both technology sides.

You already know all the tube technology limitations, like you say almost all work with coupling caps or coupled transformers, the tubes are harmonic generators and the problem is that that harmonics does not exist in the original signal, the impedance problems are bigger too when a tube amp try to handle the " electrical speaker impedance ": almost all the tube electronics are high output impedance that when is connected to cables, audio devices or speakers change the frequency response: I can go on speaking about the tube limitations but this is not the subject. I believe that exist very good designs ( within its own technology limitations ) on both sides and we the customers have the choice.

Regards and enjoy the music.
Raul.