Have Passive Preamps Finally Come of Age?


Back in the late 90s (eons ago) I tried a variety of passive preamps (PPs). The most musical was an autoformer, but back then my system was not balanced. For the last decade I have been using active preamps, both tube and solid state, but finding a quality balanced preamp under $4K is damn near impossible. Enter the Parasound P5 (2.1), which in addition to having balanced I/Os, it has a separate bass management circuit (MSRP $1095), and I was hoping it would provide better control over the built in class D plates incorporated into my 2 SVS powered subs, whose volume controls are STUPIDLY sensitive: when barely cracked from zero they overwhelm. Alas, no bueno. 

Recently i watched a PS Audio YT video that was emphatic about NOT connecting powered subs with interconnects; instead he recommends speaker cables piggybacked off the main systems amp/s. I had a spare set of DIY flat copper cables, and was shocked how much better they sounded, but doing so did not change the  volume control problem and unfortunately this id not bypass the SVS amps whose class D chips are now ancient. Thinking there could be an impedance problem led me to revisit PPs.

I sold my P5 and was using the XLR outs from my Oppo 105 (upgraded power supply and IEC/wiring to the power supply) direct to my Emerald Physics 100.2SEs (class D). The noise floor dropped tremendously, allowing me a much better view into the music. My Core Power Technologies 1800 PLC had more than a little to do with this, but...  

Days of PP research later, I came across LDRs, which seem like the ultimate PP option, but XLR versions are ~ $2K and up, with the Tortuga coming in at $2700, seems like a true SOTA bargain, just not in my current budget. Scouring the' for sale' sites I came across a Hattor XLR (MSRP $995) which was in my price range. Hattor's www had links to 2 reviews both were extremely positive: one used it in combination with a class D amp. Bingo! I snapped it up.

It arrived late yesterday, although Hattor's www pictures look awesome, they do not compare to seeing and touching it. The metal carrying case was an indication of the designer's dedication. This is an etremely well made piece of kit, but how does it sound? Alas it came with no manual and Hattor's site does not have a PDF. How hard can it be to hook up? Well, after a couple scary minutes, I discovered that it would not light up until I connected the 105. 

Stone cold, the first thing that shocked me was a further reduction in noise floor and an incredibly wide and deep sound stage, but as can be expected, it was dry. Fingers crossed, in about a half hour I began to be rewarded with texture as well. Tis only got better as the night wore on

I hope somebody chimes in with their Tortuga experience, or any other high quality PP information.that goes under the reporting radar. 
tweak1
well this could b a case of the specs don't tell the whole story, because it's probably the most authentic sound I've ever experienced in my home
tweak1 OP
 well this could b a case of the specs don't tell the whole story, because it's probably the most authentic sound I've ever experienced in my home

I believe you, as I said to you two posts back, " Tweak1 It may sound good".
  
But your not hearing the best from it, with that kind of 17kohm input impedance of this amp. An active pre in this case would probably sound better.

Cheers George 
Ralph, I always wanted to try your amps but they were always out of my price range. I love the industrial design

Keep me in mind if you are looking for claas D beta tester
george, while these are both good suggestions 

"You have two options to get the best with what you have
.
1:Send your Hattor back and get them to install the optional OPA2134 output buffer in into it, this will allow it then to drive the very low input impedance of the AA or the EP if you still have it.
2: Send the AA back and get a poweramp that has got higher input impedance 33kohm or higher"

I live in Florida so sending the Hattor back is not gonna happen (no telling how long before he turned it around), plus, having seen the insides, I don't think it is upgradeable.

I bought the AA used, so no sending it back either

Fortunately, the combination sounds damned good, certainly good enough to wait it out to get either the AA DCA/PRE (which must be a match) or the Tortuga, assuming it is compatible.   
Fortunately, the combination sounds damned good

Later then you could if you want, try from the reports a very good external tube buffer that has a low 150ohm output impedance, that is the new iFi Micro iTube2 tube buffer. I look at at this and see a serious bit of kit, if you like tube sound.
And it has it’s own passive volume control should you wish to use it instead, selectable in or out and selectable 0db or 6db gain settings, all done with the dip switches on the bottom.
https://ifi-audio.com/portfolio-view/micro-itube2/

Cheers George