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Joule Electra LA150 MkII or Lamm LL2 Deluxe?

Hi all, I am looking at a new tube preamp in the $2,500 to $4,000 used range, and I could use your help. I have tried many over the past couple of years, and my current short list includes the Joule and the Lamm. I have a wanted ad posted for the Lamm but no response yet. I have read all the stuff on both, and I am not asking for anyone to tell me what to buy, but I am interested in hearing from users about the characteristics of these two preamps, and certainly from any who have compared them directly or owned both. What to you stands out either in a positive or negative way about either of these units and, if you owned one previously, what made you switch to something else. Important to me are quietness, clarity, dynamics, midrange warmth (at least some), and bass depth, texture, and accuracy. Also, regarding the Joule, are the tubes used in that unit available anywhere else other than from Joule, and are they known for being rugged and quiet? My virtual system is accurately posted, except I am using a Zoe preamp and Cary 500MB monos, instead of the Vibe&Pulse and DNA500 shown. Thanks - Tim
mitch2
rsrex
45 posts
 
Mitch, I don't know if I'd get too concerned about the Alps pot in the Joule. From what I remember, the pot varies the resistance to ground, so it doesn't directly see the signal. I'd have to look at my La100 manual, but I seem to remember that Jud too great pains to keep the signal path pure.
pubul57
3,712 posts
 
You might want to try a Pot-in-a-Box by Music Reference/RAM Labs. It is a $135 passive using a high quality Noble pot (the same one used in by Audio Research in the old days)and it will suprise you how darn good it is compared with some of the active pres out there; I say that having owned some of the finest. You should try it and compare it with your active preamp experiments. Assuming the right sesitivity and input impedance on your amp...well, let's just say you'll think it is a really, really good deal.
mitch2 OP
3,915 posts
 
Thanks Rsrex, if I remember from building some voltage dividers a year or so ago, the shunt implementation sends the signal through a single resistor with variable resistance to ground resulting in variable attenuation. Sure enough, I looked it up and found,

Def. Shunt Attenuator - "A device made up of one fixed resistor and many shunting resistors soldered to ground and the means of selecting one shunting resistor at a time."

However, in the case of the Joule, which creates the variable shunt to ground through a pot instead of "many shunting resistors," I am not clear on whether sending the positive signal through that one resistor, and the pot side to ground, actually takes the pot out of play sonically.

What I also don't understand is why the designers don't simply use a stepped attenuator on preamps in the price range of the Joule or Lamm, since the stepped attenuator is generally considered a higher sonic quality device, and especially since Goldpoint or DACT surface mount device (SMD) stepped attenuators are generally quite inexpensive. Oh well, probably a good thing I don't design preamps, I would probably go broke trying to build one I liked. BTW, I cannot believe 67 people have viewed my wanted posting for the LL2, with no offers to sell - what are these folks reading?
Post removed 
mitch2 OP
3,915 posts
 
A little further poking around led me to the Welborne Labs site, who offer a remote controlled shunt volume control, and they say,
"Extensive listening tests here at the Labs has convinced us that the 'material composition' of the shunt resistance is not nearly as critical as that of the series resistor in the signal path...What IS important, is the shunt resistance must be low noise and linear over a very wide bandwidth to insure an accurate voltage division."
I guess that more or less answers my question.
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