Thanks Pubul57. I appreciate the comments. I plan to stay with the Cary monos so I will be running SS amps with whatever preamp I end up with. After owning two preamps without remotes, the Atma-Sphere MP3 then the Tom Evans Vibe/Pulse, I have found I am generally satisfied to set a volume level for whatever CD I am listening to, so remote is not really necessary. I am curious how Joule implements the remote? Do they simply use something like the Alps motorized potentiometer? If so, do you know whether Joule offers an alternative such as a stepped attenuator? Maybe I should call Joule directly for an answer to that one. |
Thanks again everyone, it seems I have zeroed in on two excellent preamps in the middle-upper price range, each with loyal followers. After owning a fully decked out Atma-Sphere MP3 and the Vibe/Pulse, I must say I am partial to stepped attenuators instead of potentiometers like the Alps used in the Joule. In fact that is my main sticking point about trying the Joule - that the Alps blue will limit performance to nothing better than the Zoe I am using now. I plan to contact Jud Barber today to see if he uses another type of volume control, or if he would retrofit a stepped attenuator into a LA150-2. I do see a LA100 MkII for sale here that appears to have some type of stepped attenuator and was apparantly modified by a former Joule technician, and I also seem to remember something about them having a different volume control option if remote is not needed, so maybe there is a chance.
The LL2 uses two Alps "Black Beauty" potentiometers, but I cannot find anything out there about that particular model, except maybe it is discontinued. I read in one review article that it is a stepped attenuator, but have not seen that anywhere else and my recollection is that it is simply their top-of-the-line potentiometer. My concern is that in the case of the Lamm, steps were somehow added, but it is still simply a potentiometer.
The only other preamp on my radar at this time is the Herron. I like what I hear about the new VTSP-3, being a more fleshed-out version of the VTSP-2, and I would be willing to try out the VTSP-2 since Herron offers an upgrade to the VTSP-3 for only the difference in price between the two - very cool for a company to do.
Again, thanks guys. I don't know why the preamp position has been so hard for me to fill in my system. I plan to try one of the ones listed above, although if I cannot find anything much better, I will simply stay with the Zoe, which is making a remarkably good show of itself. |
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? |
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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To update this thread, I have purchased the Joule Electra LA150 MkII and I am currently giving that a run in my system. My unit is an upgraded MkI, and Jud Barber says there is no difference between that and an original MkII. My first impression is of exceptional clarity and dynamics. This preamp absolutely does not run out of steam at any level. It never breaks up, and never sounds shrill, grainy or lean. However, it does seem a bit more in the neutral camp than I expected. However, this is compared to my former TEAD Vibe/Pulse and my other current preamp the Lector Zoe, both of which are known for having a rich presentation, and perhaps being a bit "dark." The Joule is not dark. It plays what is there, but somehow without a "warts and all" presentation. You get detail and dynamics, without highlighting flaws on lesser recordings. It is very musical. Although I do not have much experience with this preamp yet, I believe its strength may be in the more than ample power reserves and the linearity of the tubes used. It does not candy-coat the music, but it does sound beautiful.
I understand one of the upgrades (or changes) from MkI to MkII involved changing out the internal Purist wire for Cardas wire. It seems the silver wire may have been too much of a good thing, and may have limited the full rich sound that many found desirable in the LA100 preamp. Following that trend, I removed some Purist interconnects that contained silver from the Joule to my amp, and replaced them with pure copper interconnects I had around here (Sonoran). To me, the pure copper wire sounds best with this preamp. I may consider going back to Cardas interconnects or another copper cable that would be a step up from the Sonoran. Any suggestions?
Finally, I still have my wanted ad posted for the Lamm LL2, and plan to purchase one if I find one generally within the A'gon blue book price range. I suspect, from what I have read, that the Lamm may deviate from tonal neutrality (especially compared to the Joule) by being more full and robust in the bass and mid-bass, but I am not a stickler for those things and generally go with what sounds best to me. |
Hi Jamnesta, I have had the LA150 MkII up and running for about 5 days now. The only thing I can think of is the preamp simply needed a bit of warm-up to sound its best. The bass is killer, just as described by HP in TAS. I am running from the plate direct output instead of from the Mu follower circuit (this is a simple jumper switch) as recommended by Jud Barber, and I am also running the higher 8dB of gain instead of the typical 4dB, also a jumper adjustment. The preamp is supported on its own feet then on a Zoethecus Z-slab sitting on 4 vibrapods then on an air bladder suspension system. I have a HiFi tuning fuse in it and I am using a 9awg PC with special resonance shielding. After more listening, I put the Zoe back in the system to better note the differences and the Joule definitely digs deeper in the bass. The Zoe has good bass and is dynamic, but in comparison the Joule has bass you feel in your chest. For fun, I put on Morph the Cat and was just about blown out of my chair! Midrange clarity is very good also and soundstaging is wide and deep. I am not sure why I thought the copper IC's were necessary to warm up the presentation, but I put my Purist (Gold,Copper,Silver) IC's back in and it sounds even better - with improved bass definition and sonic improvements across the board, although not too surprising since the Purist cables are much better than the Sonoran's. This is a very good preamp, and very nice looking also. I really like the Standby feature, which keeps things warm but saves tube life. Jud Barber says the tubes in this preamp will last 5 to 10 years with normal use. It is also quiet for a tube preamp. I will provide a further update after I play it some more (maybe I should write a review) and I will also report comparisons to the LL2, if one ever becomes available for sale. |
To Pubul57, I believe that the plate direct output is the default setting, and according to Jud it is the most direct and best sounding. However, the output impedance from the plate direct is 1,200 ohms, which could be too high for amps with low input impedance like my former McCormack DNA 500 (10K ohms). Taken from the Mu follower circuit, the output impedance is only 100 ohms, so would match with just about any amp. Yes these are jumpers inside the preamp that can be owner-adjusted, and it is explained in the owner's manual. There are 4 jumpers in the LA150 MkII, two (one for each channel) to set the output (Mu follower or plate direct) and two to set gain (4dB or 8dB). If you are interested in discussing further, I can send some pictures and would be glad to go over it with you on the phone.
To Tvad and others, its just one of those things along my mythical search for "just the right" preamp. I have had some very good preamps through here, and the Joule is a very nice one and desirable to many, but ultimately not exactly what I am looking for. I will be trying something else in the near future and will post further thoughts. - Tim |
Cruz123, From the website, The LL2.1 features the following upgrades and modifications as compared to the LL2:
-addition of a built-in remote on/off for LAMM amplifiers
-introduction of the attenuation for gain reduction by 15 dB
-some new parts
-new knobs
-slight changes in schematic diagram I see only items 3 and 5 possibly changing things sonically, and I doubt the changes are dramatic, or they would have listed them in more detail. The caps appear the same. I would liked to have seen stepped attenuators. The more significant changes appear to be the remote on/off for Lamm amps, and the 15db attenuation switch. They were recently very helpful in helping me set up a remote on/off for my M1.1 amps. Lamm uses a high quality relay for that purpose and the remote does not even have to be hooked to a power supply, it must simply complete a circuit when the back power switch is in the "remote" position - it was very easy. They have reviews of the new LL2.1 coming up in Stereophile, The Absolute Sound and Soundstage, so we will be hearing a lot about it. |
Hi Jim, I really do have to update my system page. I sold the Cary Monos (good sounding amps but noisy). My amps are now Lamm M1.1 and the preamp I settled on is the Lamm LL2 Deluxe. That combination to me provides the richest presentation I have heard, with excellent tone, texture, and dimensionality, and very good dynamics. It just sounds more like music I would hear somewhere than the gear I have previously owned. For some reason, the Joule preamp just didn't integrate well with the system I had at the time, but the Lamm OTOH has sounded good with whatever I use it with. |
