Unison Research S6 vs S9 vs Sinfonia

Hi, we may not get DHT sound, but have you tried any KT150 amps. Also EL34 amps like Unison Research S6, Airtight ATM1. 

Hi mattam, I have tried both kt120 and kt150 but on push-pull designs. Among single ended designs which use non-DHT tubes, I have heard amps with EL84, Kt88 and 6550 tubes. To my ears it was very clear that Single ended designs clearly have a different presentation than push-pull amps (no matter whether tubes used were DHT or not). And that is where the fundamental preference comes in. I would like to have a single ended amp any day over a push-pull amp if I could get an amp that delivers adequate power to the speaker. So, if you are also considering single ended amps then look around for all the options (regardless of DHT or non-DHT tubes). Your Tannoys will love it.

Hello Pani,

I love my preludio.  I purchased all telefunken tubes and it sounds better than anything I’ve heard in a long time.  I know it is a 14 watt single ended but it drives my sonus faber Guarneri,s just fine.  I mostly listen to soft jazz.  My best recent addition was a bobs devices sky30 step up transformer with an audionote moving magnet phono and a project signature 10 table with cadenza black cartridge.  Kimber ks1030 interconnects. Audioquest redwood speaker cables. 

Just a spectacular musical experience for the money.  The telefunkens re-create the most realistic highs I’ve ever heard through the Guarneri,s.   The preludio was next to my devialet 1000pro for a while.   The 1000 pro retails at 40,000$.  
As much as I wished that the devialet would sound better , the preludio single ended won.  It’s simple realistic presentation of music is just more appealing.  The Devialet with its krell like slam is doing a good job in my home theater system. 

Single ended is much nicer sounding than any push pull. 

I have not not heard the sinfonia or performance.  I’m sure they sound nice. 

I am worried that the bigger models like the Sinfonia and Performance have much higher level of negative feedback and that could take the magic away, that's the reason I wanted to know if anyone has heard preludio and the higher models. I listen to a lot of big band and classical music so dynamics at reasonably loud volumes is very important to me. 

Dear Pani,

We have the S6 on display and it is a fantastic amp, given the right speakers it is just magical. The S6 will work woinders on your speakers and will not run out of steam. The S6 drives most of our display speakers which are 86-90db surpisingly well.

The soundstage transparency and clarity and musicallity of these amps is top notch.

Dave owner
Audio Doctor NJ