Anyone try KT150 in Primaluna Dialogue Premium HP

I noticed the same about the KT-120 tubes in a Rogue Cronus Magnum.  Switching to Svetlana EL34 tubes brought all the magic  without the etch and grain.

My KT-120s have no glare in triode mode...

I can soundly recommend the move to 150s in the HP...I went from 88s to 120s and noticed the same changes.  I didn't get so much of the fatigue but did hear the harshness / glare at higher volumes.  Great sound but it was there...but not enough to go back to the 88s or 34s.

Then I wanted "more" and after much good advice and reading, popped the $800 or so for 8 150s.  Everything I could find concern with on the 120s were removed...from the second I popped them in.  With burn-in they got even smoother.  Quite simply...I would never go back...I really love this amp with 150s.

The power has always been overkill for my Zu speakers, but they respond so well to high-energy passages that I think it improves the already impressive dynamics even further.

I have the integrated and it's superb, but I didn't realize how phenomenal this amp was until I put a few really good pre-amps in front, and the further improvements were astounding.  Running through the home theater bypass inputs, you still get the phenomenal headphone amp too.  I own a First Watt SIT-2, which is also a phenomenal amp, but the HP with 150s is just slightly better or at least as good in almost every way.  I could only give the slightest nod to micro dynamics to the SIT-2...but this is slight at best.  The HP (with 150s) has even more punch and feels even more like live music...which I know is insanely high praise given how good the SIT-2 is.  However, the HP is only that good with 150s, in my opinion.

There are two downsides to 150s in this amp...the cage doesn't fit on any longer (if that matters), and on a personal level, I do not think they are a sexy-looking tube, so you have to look at them even more with the cage off.  But sound wins over vanity!

I haven't read a post where someone regretted the upgrade for any amp that can take them.  I doubt you will prefer the 120 or 88 sound over them.

Thanks for the insightful post!  Since the OP, I have learned a thing or two, and the most important thing is that this HP Integrated is revealing of anything upstream!  

I started thinking that I may want to replace my heavily modified Jolida JD9 phono preamp.  So, I got three to audition - Project Phono RS, Channel Islands PEQ1, and Musical Surroundings Nova II.  All 3 cost about $1k (MS is open box).  GF and I compared all three to the Jolida JD9.  First thing we both agreed is that the Jolida is outclassed by all three of the others.  Nothing against the JD9, but I think it's too much tube in the mix.  The others are cleaner and clearer across the board, and the Primaluna HP was really making that obvious.  After several hours of comparison, we decided to buy the Musical Surroundings Nova II.  It has the quietest background, best dynamics, and smoothest overall sound.  The other two sounded a bit on the bright side, especially with my 803N speakers.

So, after substituting the Musical Surroundings Nova into the system for a while, I went back to the KT120s, and the glare I noticed before is 95% gone.  I think the Jolida has just a touch of tube "rush" that was being amplified by the HP.  With a quality SS phono preamp, it's much better, and I think the SS preamp just works better in the chain.  I was happy with the JD9 for a long time, but now I realize that it was boosting the highs just a bit too much for my system, and was adding a bit of fuzziness to the upper midrange.  Things are much smoother now, from top to bottom, and the glare I noticed wasn't from the KT120s.

Now, I'm still wondering about the KT150s.  Reading SQLSaviors post makes me want to go for it.  Maybe next month.  There is a guy on ebay (wpc1896) who sells KT150 quads for $275.  So, the set of 8 would be $550.  I recently got other tubes from him.  When one died after two weeks, he sent me a replacement immediately without question.  Highly recommended, and I'll probably end up buying a set from him soon.

Lastly, I have a friend who has a machine shop.  I'm going to ask him if he can make a "lift" for the tube cage so the KT150s fit under the cage.  I'm thinking of a short bar for each side with holes on top and spikes on the bottom.  Or, just a spike with a matching hole on top.  If I can get him to make something like that, should I get extras for others?  Would there be enough interest?  SQLSavior, would 1 inch of extra height be enough?

Yes!  I HIGHLY recommend the KT150s in the Primaluna.  I have the Dialogue HP integrated, and I really liked it with both the stock EL34s and some Tung Sol EL34Bs.  However, my speakers are only 86db sensitivity (Harbeth C7s), so I decided to spring for the KT150s and some NOS Mullards in the preamp section.  The difference was startling. The added power and bass depth was the first thing I noticed, but it's also a surprisingly refined tube.  The midrange is detailed but not harsh at all.  There's a real coherence to the sound from top to bottom.  Of course, the KT150 and Mullard 12au7s are about $1500, so it was a significant investment.  However, as someone else said on a different post about the HP, the KT150s are almost a requirement to get the best out of the amp.

Enjoy!
Scott