Boogie SOB 100 watt

[es336td]

Ok... I've been able to play with my SOB 100 head for a while now. I use the limit knob when I have to play at lower volumes... yeah it sucks, but not that bad. However, I've seen various reviews where techs have removed the Limit and added a Presence knob. I had a Presence knob on my old Marshall Major and used it to give me a little more bite and edge. What are the pros and cons? Are there plans/demos of this mod out there on the web? Just curious. I have a good tech in the area and if the recommendations are pretty good, I may have to change it. Another thing that would be nice would be an effects loop. Not critical, just nice. Anybody had any experience with mods to this amp? Thanx!

L

 

[es336td]

Not that anyone cares, but my love hate relationship with my SOB 100 watt head is now love. After a cap job, new tubes, and some mods, it is a monster that reminds me a lot of a Marshall. My tech added a pentode/triode switch, so I can now cut the power even more when needed, plus if I need a 50 watt or 100 watt, I still have that. I also had him modify the useless Limit knob to a Post Phase Inverter Master Volume. I now have an amazingly versatile amp and love it. Prior to the mods, I had used the two channels with a Morley AB switch to get clean and dirty. After the mods, my tech told me not to do that any more that it wasn't designed to do that. I know the Mark I came with an AB switch so shouldn't this do the same? When I used the AB, it wasn't that different, but usable. Now, I use a volume pedal prior to the amp so I can cut it back to clean. Just wondering why he said it wasn't designed to be used with an AB.

 

[user 21540]

Cool -- would love to get my hands on an SOB one day. Built like a tank, simple and loud. As far as I know they actually shipped with an A/B box but they're not really channel switchers and there is a volume disparity between the two inputs but like the MK I reissue with some guitar volume knob riding it can be done.

 

[DavidMenke]

It's not one of the most revered. It's basically a MK I reissue from 1984-1985. The MK I manual is as close as you can get to the operations. The 100 watt is the least common and there are only two with graphic EQ's that were made for Vivian Campbell.

Back in 85' I went to Petaluma to get an Amp, I tried the one going out to Vivian Campbell, and fell in love with the sound. It had Simul Class power. I ordered one exactly, minus the graphic EQ. I had reverb later installed, due to purchasing a head. Also added effects loop. This is when I had Mesa put the chassis into a 1x12 long Cabinet. Still have that amp, as pictured in my icon.

 

[woodbutcher65]

I have a 60 watt straight SOB. I found that it had a harshness to it that I didn't like, which went away when I removed a certain .003 uF capacitor from it. It sounds good but doesn't have enough gain. The limiter circuit was taken out and it got a PPIMV in its place.

It's an amp I want to put back on the bench when I have the time. Needs more gain and I want to revoice it somewhat. I have dreams of getting the boards and turning it into a Mark IIC+.

 

[mark1406]

The SOB amp’s don’t have the pull brightness switch on the second gain stage or the tone stack lift on the first gain switch.
I remember the first time I played one I couldn’t get over how different it was from my Mark 1 amp. It wasn’t as versatile either.

They aren’t a terrible amp, but they aren’t the same as the original Mark 1 amps. The transformer numbers line up with Mark 2 amps. I don’t know if that makes a difference though. The Mark 2 amps have tone shaping in the power amp feedback loop. I wonder if the SOB needs these changes?

Regards

Mark