Lonestar vs Blue Angel

[larbiere]

Apparently there exists a mod to avoid HUM with the Blue Angel. It consists in bypassing the MOJO Module. Does anybody have further information on this mod? Does it exist in a paper form or are there any informatioun on the net.

Jean-Paul

 

[voxworld]

I've never heard of bypassing the mojo box, but John Phillips has done some pretty indepth reseach on preamp tube substitution which really does work to reduce hum dramatically.
I ran mine as per his suggestions but ended up back with all 12Ax7'S.
The hum doesn't really bother me on mine.

 

[voxworld]

If you do a search on The Gear Page for John Phillips or Mesa Blue Angel you can find all this info.http://www.thegearpage.net/board/showthread.php?t=316863&highlight=blue+angel

 

[Alivefor5]

larbiere, I spoke to Rich at the Mesa factory repair facility about the really loud hum and high noise floor in my Blue Angel. His explaination was that the earlier amps had a noisey effects loop problem that was corrected in a later version (no serial number cutoff was mentioned). He said there were two ways to correct the problem. First is an expensive and complex mod to the effects loop that they could do on site or send the schematics to an authorized repair tech. Second was to replace the whole circuit board which was cheaper but at the time he didn't know if they had a board left in stock.

Later, after I was informed that they indeed had a board in stock, I sent my Blue Angel (serial number 005) chassis in for the board. The result is impressive. I've lost about 80% of the hum and noise that kept me from really enjoying the amp. Price for the board was $100 not including labor, shipping and some tubes I got.

Highly recommended mod if you've got a low serial number and a high noise floor in your Blue Angel.

 

[Chrissmoth]

As I mentioned a way back in this thread the Blue Angel has an (almost) identical pre-amp circuit to the Subway Blues.

So it might be worth trying out this mod - which only involves changing one capacitror

http://forum.grailtone.com/viewtopic.php?f=4&t=14425

As I've yet to encounter a Blue Angel I don't know if it's in the same place on the circuit board tho?

 

[larbiere]

Thanks for all the advices!
The serial number of my Blue Angel is BA-00504. Seems do be an early model too. I will first try it with new tubes such as sujested by John on the gearpage. I made an email to mesa boogie too. I will wait and see what they will answer. I tryied the 0.01 Cap to .69 Cap exchange trick too. No changes on the hum and hiss level.
Then I resoled all the bits on the board which looked not so good and cleaned all the tube contacts. This reduced the noise level a little bit, but not to the expected amount. I'm waiting on the new tubes now....

Jean-Paul

 

[Murphy Slaw]

Mine is in the 1800's and is quiet as a church mouse.

I never knew what people were talking about them hissing, being noisey, ect.

Put a NOS Mullard GZ34 in it a few weeks ago and re tubed all the power tubes with Boogies and am good to go.

Best to ya.

Murph.

 

[larbiere]

Many many many thanks

My Blue Angel's behave like a totaly new amp!!! I got the new tubes as proposed by John Phillips on the Gear Page Forum (many thanks again to give me the advise to have a look there). I changed all the tubes except the power tubes as said there, and .... the hiss is totaly gone. What a difference. Hey guys, I'm so happy now with this Amp. It was my first Mesa Boogie I ever had. And must agree, that the tone was splendid even with the terrible hiss in the background, but I was a little bid disappointed because of that level of unwanted noise it did. But now .... wow!!!! what an Amp!! Great! Extraordinary! Many many thanks to you guys again. I'm so lucky that I found this page on the net!

Jean-Paul, most happiest Mesa player this evening