Phono Stage - Passive Pre- Amp: Results??


Has anyone used a passive pre between their phono stage and amplifier with good results? If so, could you share the specifics regarding hardware? thanx much in advance.
pawlowski6132
I use the Mod Squad Duet, which is a Phono Section and a Passive Pre. I love the thing. I got it from another Audiogoner here a few months ago. It works wonderfully. I have no problems with lack of gain and it is incredibly transparent. Check out my system for more comments on how it works.
Pawlowski6132, cable capacitance does play a role, but a more complex one than generally meets the eye. In addition to high frequency rolloff caused by the high output impedance of the passive control and the cable capacitance, the interconnect also has something called Characteristic Impedance (which cable capacitance plays a role in).

Characteristic Impedance is the property of the cable such that it will have no reflections when terminated at its characteristic impedance. IOW, a cable with a 150 ohm Characteristic Impedance will exhibit reflections unless a 150 resistance is placed across the cable.

The reflections in an unterminated cable are quite audible and is one of the differences you hear in cables, as nearly all of them have different CI. The lower the output impedance of the output that drives the cable, the less audible the reflections become.
Benz Lukaschek PP1 v9 into either a Bent TAP or a Placette Passive, then into a Gamut D100 or Nuforce Reference 9SE. 1M interconnects. Success with all combinations.
More so an issue with resistor based passives that transformer basaed, but still worth while to look into.
If you are running passive between the phono preamp output and the power amp, you will find that keeping the interconnect cables as short as possible will be very beneficial.
I use a Ortofon Jubilee at .35 through a Loesch phono pre (70db gain?) with stepped attenuators, cartridge/fet-tube-tube-tube-volume/amp/speakers. It drives my Berning EA-230 and Quad ESL's (84-86db effecient?) just fine (medium to small room) and very transparent and dynamic. I rarely go past 1 o'clock for volume. IMHO you should pay close attention to the output impedance of the pre and input impedance of the amp.

Carl
I have an Ayre P-5xe running balanced into a Diy Dact balanced attenuator to a Rowland Model 2 with perfect results.
I use a Benz Lukaschek PP1 v9 for my Benz Silver Ref MC cartridge, which goes into a specially modded QED passive, which goes into my Eagle 4 amp. No problems, great sound as far as I can hear. Interconnects are Cardas Golden Cross and Ensemble.
Monolithic Sound phonostage + Channel Islands passive.

Your mileage may vary.

I use a Modwright modded Marchand X9 Deluxe electronic x-over, which makes things even beter. I figured that's the ticket, having the best of both approaches.

***
I have probably one of the worst scenatios. LP12/Cirkus/Ekos/Lingo with 0.15mV Troika into an Aqvox 2CI MkII phono stage (72db gain) into Reference Line Preeminence 1B, Sonic Frontiers Power 2 1.25V RMS for 110 Watts into Totem Mani-2s 85db/W/m. This is all run balanced. The cartridge has very low output and the speakers have very low sensitivity. But it all works.
Same as Ozzy62, except my K&K phonostage and K&K TVC with S&B transformers are a two box set-up. My phonostage has 64db of gain for MC and I've used it with cartridges ranging from .3mV to .8mV. The input sensitivity of my amp is .8V and has an input impedance of 67k ohms. Speaker sensitivity is 88db. Works great for me.
My preamp is a custom piece consisting of a K&K Audio phono stage and S&B TX-102 trannies. The phono gain is 70db and the input sens. of my amp is .75v. Cartridge output is 0.4 mv. Most speakers I use have varied from 89-92 db sens. and this worked great with all of them. I even had success using Magnepan 3.5s in this setup.

Oz