PrimaLuna Dialogue Preamp = emotionless?


After years of running a PS Audio Direcstream dac directly into ATC active floorstanders, I decided to take everyone’s advice and add a preamp into the mix. I picked up a used PrimaLuna Dialogue with highly regarded Mullard CV4003’s and Phillips 5R4GYS’s, the tubes purchased by the original owner five years ago from Upscale Audio, a terrific source. My correspondents were correct about adding a good preamp: it transforms everything in a very big way. That’s the good news -- and bad. The latter is the reason for posting.

Before the preamp, this was a modestly warm system, for which the Directstream is known. It was one in which it was not hard to find myself drawn into the music and performance. Since adding the PrimaLuna however, I find myself watching -- or listening to -- emotion but not feeling a thing. That is, beyond marveling at the other characteristics of the presentation. After that, I’m left perfectly cold - 100%. This is not at all what I expected -- or desire.

So what to do... Is there anything I should look at with the preamp? What about other preamps, preferably tube ones? The skinny these days is that tube gear developers are trying to imitate the "neutrality" of solid state, the so-called modern tube sound some call it. With the PrimaLuna, I was expecting to find a point in between the classic tube sound and the common solid state one, but what I’m hearing is more than a little distant from that.

(Other than adding the PrimaLuna and not having Ultimate beeswax fuses in the DS and PL currently for other reasons, nothing else in my system has changed: modified Oppo 203 w/ digital output only, PS Audio P15 Regenerator and AC-12 power cords, and MG Audio Design AG2 ICs,)
highstream
@helomech - I don't understand your suggestion. As indicated in the OP, I ran from the Directstream to the speakers directly before adding the preamp. Hence the comment on how much of an improvement the latter was in all ways but one.

I got a reply from PL NA today that says the Mullards should be warm, and suggested changing the input tubes and, failing improvement there, take a photo of the bottom insides to see if any modification had been made.

The first pair of Brimar CV4003's, inserted in the center slots (6 in total, 3 each side), are having the same effects I've seen many times with a new cable. That is, the sound is warmer but lacks clarity and dynamics and is a bit recessed spatially. Have to see what develops with burn in. 
Of course, maybe it's the Philips rectifiers that have seen their day. They should be warm too. I had a similar problem with the stock rectifier that came with my Lampi Atlantic TRP dac (currently being repaired). After trying a few others, I found an Osram U50 that gave the dac more warmth and a whole lot more. 
highstream...If what you mean by ’emotionless’... the music not pulling you into the performance...I would have to disagree with your findings. My PL is a music making machine that brings out the best that the the DS dac has to offer. I have tried many different tube types...and for my likes... the Amperex NOS 7316 is a great tube for revealing the best of what the the PL has to offer. For the recifiers, I like the Brimar NOS 5R4GY. They are a bit more musically involving than the Phillips,which can sound a bit to dry for my liking.

Also..the 7316 foil d getter [1958] is a killer tube that I use in the center slots. It brings/adds a touch more humanity to the table... 8)
The published 256 ohm output impedance is most probably measured at 1KHz and can be (and most likely is) much higher as the frequency response varies during actual music playback. A 10K input impedance is lower than average for a solid state amplifier and is probably a better match when paired with the (solid state) PS Audio component.      
less is more in the idea of electronics in the audio chain.

If one had a very satisfying sound quality with active speakers, before a preamp was added in..and then had ’perceptively’ worse sound quality after a preamp was added in, then..get rid of the preamp, and go back to being without a preamp.

I’ve had my hands inside of and torn down and modified some good 50 preamplifiers of all brands and quality levels, besides rebuilds of preamps for others. mostly done with single cause analysis in the chain of modification(s) done in each unit.

The conclusion is that if the load of the source as compared to the input of the amplifying device..if this pair is well matched..then.. the addition of an active preamp will likely be degrading. Ok, will inescapably be degrading.

Even a single piece of wire is degrading to sound quality. So a box of active and passive components, that the internal and overall distorting and signal changing/damaging interactions count into the hundreds...

..where this 100+ interactions device, is called a preamp..that if this device is added in, then the simple logic is that --- it degrades.

It’s supposed one single advantage is that it is supposed to better match impedance between source and input/load, and if that part is taken care of already..then the preamp is a clear cut degradation to the given optimized system.

in 35 years of playing with audio gear re my hands inside of it and making rebuilding, doing it all as single cause analysis down to single resistor changes and the like...this... informs me that preamps are almost always a degradation to the sound quality of an audio system. that their advantages are limited.

Where logically, by all possible methods of analysis..that a complex device like a preamplifier is 100% a source of signal degradation, and one must try and decide if that degradation is outweighed by the single benefit of better signal impedance matching (cables must be added into this calculation) to the input circuit of the amplifying device.

I know it would be best for me to encourage you to buy more cables as we make and sell cables, but in audio ’less is more’, and that --- is inescapable. It is due to how signal itself interacts with conductive materials, dielectrics, transistors, and so on.

Re the subject of fundamental single cause analysis..when one goes completely to ground in the most fundamental way possible, at the primary divide.. in the realm of electricity being the carrier for/of signal at the molecular interactive...We designed and built and sell the liquid metal cables and they are utterly unique in the realm of signal conductors of all kinds (in the world), being fully liquid at room temperature, and requiring the application of complex math surrounding Quantum Electrodynamics (QED) and higher level math electrokinetics to analyze.... and this math and science is unsolved at this time.

Basically put, people get a chance to hear what wire sounds like for the first time in their lives (collectively and individually), like a fish that experiences the difference of ’other’ (outside of water) for the first time ever.

This is difficult or impossible to do in audio, due to the generally hundreds of interactions in an entire system, that are all conflated - inside chains or series of black boxes. So we presented to all... for the first time in audio, period, the essential single fundamental -- as a difference. It is actually a really big deal, for those who think it through.

There is a lot of detail and points I’m leaving out of my argument (preamps and the idea of fundamental single cause analysis in the complex chain of audio), re things people will hold up to question, but think of them as being there, but unspoken.... as I’m not going to write a thesis or book chapter on it..