Adjustable Bias Mod Kit First Impressions

[Jared Purdy]

Anyone try this on a LSS? And, does that bias mod kit work on the LSS?? Thanks.

Apparently the LSS is cathode biased (kind of self adjusting), so the bias mod, which is meant for fixed bias amps does not apply. I am no expert so any one knows different......................

Ive been told by my amp tech the best thing to do for my LSS is just give it to him and he'll find a set of tubes (he has plenty) that run a little hotter than stock. And then if I like them just stick with those tubes from now on.

It takes a little trial and error but it gives the same effect without having to rebias the amp.

Thanks, so what tubes are you running in yours? Mine is quite new, so I'm not sure what I want to do about the tubes, as the amp sounds pretty good. I blew 3 5Y3's in 7 weeks, and that problem was supposed to have been fixed by Mesa sometime ago. The serial number on mine is 005300~, which puts it considerablely past the serial number range where they supposedly fixed it (clipped a couple of resistors). I was also told that the current Mesa 5Y3's out there are crap. I put in a Sovtek on Friday, and have been intentionally playing it, putting it on standby, playing, etc. as much as possible sine then and so far no problems. Still though, curious to hear what tubes you're using.

 

[Vogelsong]

Ive been told by my amp tech the best thing to do for my LSS is just give it to him and he'll find a set of tubes (he has plenty) that run a little hotter than stock. And then if I like them just stick with those tubes from now on.

It takes a little trial and error but it gives the same effect without having to rebias the amp.

Thanks, so what tubes are you running in yours? Mine is quite new, so I'm not sure what I want to do about the tubes, as the amp sounds pretty good. I blew 3 5Y3's in 7 weeks, and that problem was supposed to have been fixed by Mesa sometime ago. The serial number on mine is 005300~, which puts it considerablely past the serial number range where they supposedly fixed it (clipped a couple of resistors). I was also told that the current Mesa 5Y3's out there are crap. I put in a Sovtek on Friday, and have been intentionally playing it, putting it on standby, playing, etc. as much as possible sine then and so far no problems. Still though, curious to hear what tubes you're using.

As far as power tubes go Im still running the stock Mesa's. It's not that Im in love with them its more the fact that I havn't had time to take it to the tech to do the trial and error. And 2...lets just say Im broke.

As far as the rec tubes go. Go online and find a reliable source for a 5v4 rec tube. Preferrably an NOS. That will take care of Rec tube failures. Mesa says it will void your warranty, but it is a 2amp tube just like the 5y3 so they can kiss my ass.

 

[Jared Purdy]

Ive been told by my amp tech the best thing to do for my LSS is just give it to him and he'll find a set of tubes (he has plenty) that run a little hotter than stock. And then if I like them just stick with those tubes from now on.

It takes a little trial and error but it gives the same effect without having to rebias the amp.

Thanks, so what tubes are you running in yours? Mine is quite new, so I'm not sure what I want to do about the tubes, as the amp sounds pretty good. I blew 3 5Y3's in 7 weeks, and that problem was supposed to have been fixed by Mesa sometime ago. The serial number on mine is 005300~, which puts it considerablely past the serial number range where they supposedly fixed it (clipped a couple of resistors). I was also told that the current Mesa 5Y3's out there are crap. I put in a Sovtek on Friday, and have been intentionally playing it, putting it on standby, playing, etc. as much as possible sine then and so far no problems. Still though, curious to hear what tubes you're using.

As far as power tubes go Im still running the stock Mesa's. It's not that Im in love with them its more the fact that I havn't had time to take it to the tech to do the trial and error. And 2...lets just say Im broke.

As far as the rec tubes go. Go online and find a reliable source for a 5v4 rec tube. Preferrably an NOS. That will take care of Rec tube failures. Mesa says it will void your warranty, but it is a 2amp tube just like the 5y3 so they can kiss my ass.

That has become my thinking too! In fact the manager of the store that I bought the amp from said that Mesa is full of **** for saying that! I am currently running a Sovetk 5Y3, and I have had the amp on ALL day! I met a audio repair person this weekend who has a pile of NOS tubes, all kinds, that he is more than happy to sell me. So while I am there buying tubes for the Messa, I will also be buying some tubes for the 65 BFDR that I'm picking up on Tuesday!!