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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
georgehifi's avatar
georgehifi
4,966 posts
 
The PPs suck dry musical dynamics, timing and related details.

That could be true if you weren’t impedance matched.
An active preamp can’t "make" these out of thin air, compared to a "impedance matched" passive preamp, it's already there in the music that comes from the source.  
Remember what Nelson Pass says about passive preamps

Remember what Nelson Pass says about passive preamps

"What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection.

And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp."


Cheers George

tweak1 OP
870 posts
 
eric,

you may be confused as to which Parasound is the worst. My first was the P 3: the P5 was clearly way above it, but nothing like the Hattor. From there, the only 2 channel upgrade would be  the JC 2 @ $4K well out of my budget, even used

We tend to expect one thnew thing to make our systems sing, when seldom will it work that way

As to dryness, etc I find the opposite of bpoletti's comments. at least with the Hattor, which puts everything into fine focus with great speed, and timing. What IT is doing is ruthlessly exposing everything else, including the recordings. On many CDs, some songs are well recorded while  others are downright awful.

Jadedavid: The lack of soul was likely elsewhere (see my opening comment)

When I initially connected the H, I used a $100 Cullen PC, and PS Audio XLRs. The next afternoon, I replaced the Cullen with a $300  WireWorld PC and Surf Cables XLRs (absolute bargain) , the sound immediately warmed up (instruments and voices much fuller bodied, and the music now has 'more' texture.

I believe my  lowest common denominators now are 

1. My Emerald Physics 100.2 SEs (probably 2-3 generations old class D) 
2. My Oppo 105

The amps will be the first to be replaced with a Nord stereo amp

I considered the $2K++ W4S STP SE, but IMO it's butt ugly, with a tiny view screen. Very poor design, especially for the money
tweak1 OP
870 posts
 
Another thing I did after IC and PC swap was to raise both the H and its power supply up on Machina Dynamica springs. Anther positive step that was instantly heard. These inexpensive iso/vib control devices are the real deal
bpoletti
1,004 posts
 
@georgehifi The PP can certainly filter out signal.  And yes, it's due to an impedance mismatch.  
erik_squires
5,268 posts
 
@tweak1

You misspelled my name, but I'm guessing you are talking about me. :)

Sorry, I meant "current production Parasound pre's."  Never heard the P3.

Best,
Erik

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