KT88 Tube Sound Listeners: The KT88 tubes present a more transparent sound than the EL34 tubes. I actually felt the KT88 tubes were terrific match with the Dialogue One. This would be a great for those people who love the KT88 sound. And for those who already have the KT88 tubes available I would skip the Dialogue Two and purchase the Dialogue One, then replace the EL34 tubes with KT88 tubes.

Yet with either type of tube I found the sound was less open and airy, the midrange not as forward, compared to the Prologue Two. And with the EL34 tubes the Dialogue One sounded slightly veiled and missing the clarity compared to my Prologue Two with EL34 tubes installed.

Since I love the EL34 tube sound with the Prologue Two I started testing with different configurations to isolate the problem with the Dialogue One. One the first things I noticed was too much bass, so I changed the taps for the Energy RC-30 speakers from 4 ohm to 8 ohm, which worked out very well. I swapped the Primaluna EL34 tubes to Siemens EL34 tubes. But I noticed no difference in the sound (good sign for the Primaluna EL34 tube design characteristics). Tried the Triode/Ultralinear switch. It does modify the sound and at times one setting or the other sounds better with a particular cd. But I was getting inconsistent results compared with Prologue Two, which sounds excellent with a number of cd’s. Swapped speakers from Energy RC-30 to RC-10/subwoofer without success.

After unsuccessfully isolating the problem I checked specs for both models:

The Prologue Two has the upgraded solen capacitors and fast recovery diodes.

The Dialogue One does not.

I started to suspect the clarity of the EL34 sound I enjoyed with the Prologue Two was dependent on the upgraded solen capacitors and fast recovery diodes. I concluded I needed to exchange the Dialogue One for the Dialogue Two, which has the upgraded solen capacitors and fast recovery diodes.

EL34 Tube Sound Listeners: I highly recommend you audition the EL34 Dialogue One and KT88 Dialogue Two with EL34 tubes installed before making a purchase.

Part 1: Comparison: Primaluna Dialogue One to Primaluna Prologue Two

My previous experience with Primaluna is the Prologue Two. I have been very happy with it after swapping the Primaluna KT88’s for Siemens EL34’s. Since my preference was the EL34 tube sound (mostly for jazz, with vibes, keyboard, vocals), I purchased the Dialogue One, an EL34 based amp. Current speakers: Energy RC-10 w/Polk Audio PSW-111 subwoofer and Energy RC-30 speakers.

Prologue Two: Whether using the EL34 or KT88 tubes the presentation is very open, airy and intimate. Like being at a live performance with the performers 10 feet away. You’re drawn into the music. Less detail captured. Bass is not as defined, with the midrange and highs emphasized. Good soundstage.

Dialogue One: A more accurate interpretation of the recorded music. Able to capture more detail within a recording. Better bass control with more impact. Performers are easy to identify their location within the soundstage. The presentation is more laid back with either EL34 or KT88 tubes, like the performers are 20 feet from you.

Customer Service

Part 2: My experience working with Upscale Audio on the purchase and exchange

I contacted Kevin Deal of Upscale Audio to address questions and concerns I had regarding the Dialogue One and the type of sound I was trying to achieve. After Kevin answered all my questions I decided to purchase the Dialogue One without hearing it. I picked up the amp at his location after an informative tour of the facility, which I enjoyed very much.

I spoke to Kevin Deal a few days later requesting an exchange to the Dialogue Two, providing details of my troubleshooting and my conclusions regarding the upgraded solen capacitors and fast recovery diodes. I also advised him I was aware of the restocking fee (10%).

Kevin agreed to the exchange and he reduced the restocking fee to an amount I felt was more than fair. Overall a pleasant experience.

Similar Products Used:

I currently have the Dialogue Two and will post a review at audioreview.com soon.

everything and more ..
now crappy cd's and the such sound grewat again..

highly recommended

?

wow ,,
my opinion on this amp just having owned it in less then a week,

wow
having owned the primaluna one driving my maggies 1.6 ,,I heard about this amp from herman first himself.. i emailed him before it was released in north america ..
probvably the first ownber in toreonto..
and this may be my first journewy into high enfdd sound //
I am alspo using a veryt heavy cary audio dvd player for 2 channel

and wow ,,the weight,detail,,
I gcan gpo on and on,,
but I really don't think I would upgrade from here ,,
unless I win the lottery.
enjoy

Similar Products Used:

primaluna one
nad
krell.
bryston.