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
George, your info would be spot on IF the AA did not have 2 gain options (I was unaware how valuable that is). I didn't try the base gain until late last night: where did the music go? I quickly reengaged the + 6dB and viola. Im a very happy camper again. And I am not abe to use (and not missing) my 2 SVS Ultra powered subs, which is more evidence of the EP/Hattor mismatch

Eventually the Hattor will go to a new home, to be replaced by either an AA DDP-1 (but I don't need either the dac or the headphone circuit) and if the dac is better than in my Oppo 105 I'm guessing I would need to switch it in/out when listening to non SACD format:and if so, no bueno, but I think I can get one with power supply in the $1500 range. If so, I probably will. So far the Tortuga LDRxB is at the top of my wish list, but it's $2700. I could stretch to half that amount, but don't see that happening :(.

I decided against the Nord for several reasons

* it would take 3-4 weeks and I was music-less
* it had tons more power than my 94dB KCIIs need to jump out of the speakers, and my new speakers are 96db
*  the AA was almost half of the Nord price

Thanks again, though
@georgehifi I agree with your assessment of impedance mismatch between the Hattor passive (unbuffered) preamp and the choices of amplifiers that tweak1 selected. 

@tweak1 You initiated this thread discussing passive preamps, yet you have nearly changed everything downstream to accommodate it (that is, the Hattor passive unbuffered preamp). This includes a new amp, a different set of speakers and ditching your powered subs. I respectfully disagree with your assessment that a simple gain switch will rectify the impedance mismatch George referred to. Just for kicks, why not obtain his suggested amp to audition? You’ve changed so much already; one more audition won’t be much work. And don’t be afraid to liberate yourself from the need of a class D amp, unless you are worried about electric bills. There are a lot of good design topologies that will likely bring smiles to your face when mated into your system.

Trying is the pudding of life. And I know you at least enjoy trying new gear!  

Just my two cents!! Enjoy the music!!  
Your assumption that I am doing all this just for the Hattor is incorrect. And 'respectfully disagreeing' doesn't change the reality

The changes were already in motion as I had sold my Parasound P5 preamp and had been using my 105 direct to the EPs for a couple months while I investigated preamps. Having owned the EPs for several years, it was time in class D years/advancements to upgrade

My plan to get the Nord ended when I realized it has way too much power for 94 dB speakers, which are even more amazing with the DPA-1s ability to provide an impedance match with the push of a button. The Nord is made and shipped from the EU, auditioning is out of the question. The speaker upgrade was unexpected when a unique opportunity presented itself

Of course I want to use the subs, BUT, AA owners manual specifically says not to piggyback off the DPA-1.. I am awaiting a reply as to why,. BUT.... the 3 D venue reproduction is so vast and the bass so strong with the AA that I don't miss the subs

Anything else you want to be wrong about? 
@tweak1  Wow. I’m sorry you took offense to my post. Remind me not to suggest anything again on one of your threads. You seem fairly confident in shooting down everyone’s suggestions with some defensive or snide remark. 
ROFLMAO. Had you ASKED questions instead of assuming, I would not have added the last sentence