I guess this thread is the reason why I have been getting several recent phone calls about Joule-Electra gear! :-)
Some general notes/thoughts....
6C33 Tube Sockets - Ralph (Atmaphere) knows way more than I do about the variations and types of these. What I can report is that as long as the tubes are not often messed with (bent around in their tube sockets), they generally hold up fairly well. I have not had to replace many. I do carefully give them a visual inspection whenever a amp comes in... looking for signs of carbon caused form poor contact tension (sometimes arcing). Sometimes they need a little tweaking (tensioning) to make sure the contacts are fitting right on the pins. Given the layout of the board and how the sockets are mounted in the amp, making other sockets (with different mounting points) is not something I have tried just because it did not look practical, cost effective, or possible to do.
The amps can be a bit fussy (to operate) and Variacs can be a problems on the early versions, but in general they a quite reliable and make great music.
The phono preamps susceptibility to RFI (quite literally radio station signal creeping in) is limited to MC operation in my experience. Later versions (MKIV/V) seem to be better in regards to this and the problem tends to rear its head with folks who live close to radio station transmitting facilities.
As to tubes use and cost.... the preamps and amp are not hard on tubes. The 6350 used in the amps, and preamps though not currently made, is not a hard tube to find NOS samples of... and a get set of 6350's in a LA-150MKII for example, will last around 4 years or more depending on use. Jud, generally used good NOS tubes in his gear so that I generally what I like to stick with (except for the 6922/6DJ8 used in the phono preamp and OTLs). The older preamps use OA2 for voltage reg, later on Jud switched to a Zener diode to replace them. There are also 6EM7's in the power supply and those hold up quite well (lasting about twice as long or longer as the line stage tubes IMO) and they are not expensive or not hard to find NOS examples. So, it could cost $300 to completely retube a preamp, but the thing is, that is generally never necessary. When a old preamp comes in for a check, I may generally replace a couple of the line stage tubes as the ones in the power supply usually tube test and measure in the preamp fine, then tweek the line stage bias adjustments and then send along its way.... they are great preamps and generally very reliable. I'll never sell my LA-300ME.
As you can tell, I'm pretty found of Joule gear... will continue to do what I can to continue supporting it to see that it lives on in use for its owners and fans.
Rich Brkich
Signature Sound
Some general notes/thoughts....
6C33 Tube Sockets - Ralph (Atmaphere) knows way more than I do about the variations and types of these. What I can report is that as long as the tubes are not often messed with (bent around in their tube sockets), they generally hold up fairly well. I have not had to replace many. I do carefully give them a visual inspection whenever a amp comes in... looking for signs of carbon caused form poor contact tension (sometimes arcing). Sometimes they need a little tweaking (tensioning) to make sure the contacts are fitting right on the pins. Given the layout of the board and how the sockets are mounted in the amp, making other sockets (with different mounting points) is not something I have tried just because it did not look practical, cost effective, or possible to do.
The amps can be a bit fussy (to operate) and Variacs can be a problems on the early versions, but in general they a quite reliable and make great music.
The phono preamps susceptibility to RFI (quite literally radio station signal creeping in) is limited to MC operation in my experience. Later versions (MKIV/V) seem to be better in regards to this and the problem tends to rear its head with folks who live close to radio station transmitting facilities.
As to tubes use and cost.... the preamps and amp are not hard on tubes. The 6350 used in the amps, and preamps though not currently made, is not a hard tube to find NOS samples of... and a get set of 6350's in a LA-150MKII for example, will last around 4 years or more depending on use. Jud, generally used good NOS tubes in his gear so that I generally what I like to stick with (except for the 6922/6DJ8 used in the phono preamp and OTLs). The older preamps use OA2 for voltage reg, later on Jud switched to a Zener diode to replace them. There are also 6EM7's in the power supply and those hold up quite well (lasting about twice as long or longer as the line stage tubes IMO) and they are not expensive or not hard to find NOS examples. So, it could cost $300 to completely retube a preamp, but the thing is, that is generally never necessary. When a old preamp comes in for a check, I may generally replace a couple of the line stage tubes as the ones in the power supply usually tube test and measure in the preamp fine, then tweek the line stage bias adjustments and then send along its way.... they are great preamps and generally very reliable. I'll never sell my LA-300ME.
As you can tell, I'm pretty found of Joule gear... will continue to do what I can to continue supporting it to see that it lives on in use for its owners and fans.
Rich Brkich
Signature Sound