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Quality passive preamp?

Hmm one of the benefits of a passive pre is the lack of complexity, adding a remote, a display, and load of bells and whistles to a switch and resistor seems, um, a little mad?

EDIT: I can see I am in a minority, as you were, I guess I stand up to change sides/CDs and adjust the volume while I am up if necessary, no need for a remote for me, happy to be a content minority with no bells or whistles
 
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Although I own the Diy DC B1 I am still curious as to how a Townshend Allegri, a Hornshoppe "The Truth", a Wavac ATT-S or LDR passive pre would compare.

I also read that the Tom Evans the Vibe should sound very neutral but still bring out details in a similar way to the DIY DC B1.
 
Are you sure the Townshend Allegri is using resistors?
It uses autoformers.
Just thought I'd put in a word for the maligned potentiometer. For my homemade passive I use a TKD potentiometer, about $75. Over the years it has bested Slagle autoformers, resistors, digital attenuation in my Mdac (and I forgot -a Bryston active). I keep coming back to it.
 
I have the original Allegri which has a plastic case with some bits of thin metal stuck on.
It also does not have any resistors in it.

It is a pain having to get up to change the volume, so the remote control is a nice feature on the new £6.6k unit.
 
What's so wrong with autoformers?

Same thing that's wrong with any and all transformers in the audio path... colouration, ringing, distortion and reduced bandwidth. Many love them. I would never use them. A normal passive consisting of nothing but resistors and switch contacts measures vastly better.

If you must have low impedance drive to the next stage then use a buffer or an active pre as it's less intrusive.
 
Same thing that's wrong with any and all transformers in the audio path... colouration, ringing, distortion and reduced bandwidth. Many love them. I would never use them. A normal passive consisting of nothing but resistors and switch contacts measures vastly better.

If you must have low impedance drive to the next stage then use a buffer or an active pre as it's less intrusive.

And this is pretty much where what seem to be the benefits of passives run into the real world.

They often present significant impedance mismatches to the sources that drive them. IME, this can be a particular problem for phono stages. If what you want is something between a line source (at 2V) and, say a Quad power amp, it's great.

If not, then, possibly not.
 
And this is pretty much where what seem to be the benefits of passives run into the real world.

They often present significant impedance mismatches to the source drives them. IME, this can be a particular problem for phono stages. If what you want is something between a line source (at 2V) and, say a Quad power amp, it's great.

If not, then, possibly not.

Nope there is no "impedance mismatch". An impedance matched environment is usually used in RF work where 50 Ohms is the norm. There was once a 600 Ohm standard in telephony usage but that's not relevant to this.

A phono stage has the same output impedance as an active pre or the output of a CD player or DAC, any big differences usually due to no output follower (buffer) being used in a very few valved phono stages... oh and a very few pre amps such some Audionote ones. All the above generally range from around 10 Ohms to 1000 Ohms output impedance and can drive the usual 20K or 50K passive no problem. In fact many pre amps consist of a passive of often 50K at the input which is then followed by a X 2-3 gain amplifier section or a buffer (no gain) and so often you are in fact driving a 50K passive! Also many integrated amps are a passive connected to a power amp, all in one box with a source selector.
 
Thanks for the replies.

You won’t close this thread so easily :)

Arkless knows the proper stuff but all I know is passive was a revelation for me. The Khozmo trounced the Michell Orca that I loved and that trounced the Naim 52 that trounced the 82 with umpteen psus. The only active pre that’s really impressed was a top of the range Dynavector and the Khozmo trounces that. (I think).
 
You won’t close this thread so easily :)

Arkless knows the proper stuff but all I know is passive was a revelation for me. The Khozmo trounced the Michell Orca that I loved and that trounced the Naim 52 that trounced the 82 with umpteen psus. The only active pre that’s really impressed was a top of the range Dynavector and the Khozmo trounces that. (I think).
Yep, passive and the allegri have been a revelation for me too .. outperform some well liked active pre ... so not sure about that dude armless knowing much about anything ...
 
Khozmo user here...bought one used off the Wam, it's previous owner moving up to a custom Hattor unit with remote switchable inputs.

Mines got a remote for volume, standby and display brightness. The build quality is fantastic and it sounds excellent, beating my Naim pre and the Tisbury. The Tisbury was a revelation but the lack of remote drove me nuts, more because I generally listen to streamed music and the variation in volume requires constant fiddling.

Feeding into a Quad QSP I get no issues re impedance matching.
 
Khozmo user here...bought one used off the Wam, it's previous owner moving up to a custom Hattor unit with remote switchable inputs.

I tried a Hattor in my system, borrowed from a friend and a nicely put together bit of kit. We are both using the Allegri (old style) in preference. Doesn't mean one is automatically better, just that in our systems the Townshend was the winner.

I have an Oppo 105D and in my system I would rank its pre function and the Hattor equally.

Systems:
dCS NB > AN 4.1 > <Pre> > Pass or Naim 250DR > AN speakers; or
Linn Klimax DS > <Pre> > EAR534 or Naim CB250 or Avondaled CB250 > Focal 1008be II or Naim SBL
 


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