Information for Joule Electra LA100 Mark III


Hello,
if someone has an owner's manual for this preamp and can email a copy to me,or just mail it I would really appreciate that.Also what is your opinion on LA200 and LA150 preamps,how would you compare these 3 to each other?Thanks a lot.
rohlim
I have the manual and the instructions for biasing the tubes. Email with your address.

I bought an LA-200 (based on the serial number the first unit made) about a year ago from the person who originally reviewed the preamp in PF (the review is on the Joule website). I sent the preamp to Jud and he upgraded it to an LA-100 MkIII. Other than cosmetics, the LA-200 and LA-100 were pretty similar. The LA-200 was top of the line until the signal path circuitry was changed and the LA-100 MkIII was released (6350 Mu follower replaced the 5751). The main differences were in the output impedance, where the LA-200 was not recommended for use with amps under 100k ohm input impedance, and gain where the LA-200 had slightly more gain than the LA-100 (although on both preamps this was adjustable, the LA-200 uses 4 rocker switches in 2db increments and the LA-100 has jumpers for 2 settings).

The only other difference was the power supply tubes where the 10EM7 tubes found in the LA-200 became obsolete and instead the 6EM7 was used in the LA-100 MkIII (I believe earlier versions as well but not sure). Both preamps were offered with the Purist Audio wiring option (versus stock Cardas) and remote option. The LA-200 was stereo only and the LA-100 featured a Stereo/Mono switch. Also, I believe you could stipulate dual volume controls or volume/gain controls for each unit, although mine is dual volume and Jud recommended I keep it that way.

Both these preamps are warmer and more musical than the LA-150 which uses the Russian tubes. I think the LA-150 is a great preamp, but there are many more preamps like it, some like the Herron that outperform it. For the money, the LA-200 or LA-100 MkIII is tough to beat in its price range, especially used.
The MKII version of the LA-150 has a richer more musical sound than the earlier versions. The gain stage uses all 6350's (no more Rusian tubes)but otherwise is identical in topology to the original 150.

Jud Barber - Joule Electra
Wow... it is good to see Jud posting here.

I have an original LA-100 Mk III with Purist wire and Remote options (not an upgraded unit) and I absolutely LOVE IT!

I even sent it to Jud last fall to add an additional 3db's of gain (new jumper added).

Amazing preamp.