Stock '72 Superbass 100w - Recommendations?

[jcmusic]

So I have, I believe, a stock '72 100w Superbass. Long story short, an ebay find around 10 yrs ago that went into storage before I took off for a couple tours in Iraq. I just dropped it off at a reputable tech but am looking for any recommendations on what should be done. It looked original inside (clean) with an old nasty non-grounded power cord attached. Guessing its completely stock, but not sure.

I'm mostly interested in fairly cleanish plexi tone, big warm punchy tube sound & will drive/boost it with od pedals. Want to avoid any ice-picky gnarliness. Will be using a maple neck 80's Strat w/ single coils (SD SSL-1s).

Any recommended minor mods I should be aware of? Guidance from the experienced would be greatly appreciated.

thx!

 

[jack daniels]

You could install a Trainwreck influenced PPIMV as AMS (ampmadscientist) here on the MF recommends them over the Lar/Mar PPIMV, AND possibly a Metro Amps effects loop (reversible) BUT this would leave you with only one cabinet jack as the other three cabinet jacks would typically be used for the PPIMV pot and the effects loop send and return leaving one cabinet jack. The PPIMV would make the amp more controllable when turning up, and the effects loop would be more effective for all of your time based delay pedals (or rackmount time delay units) that would muddy up your signal by running them directly before the amp's input or input(s) if jumpering channels. Other than the aforementioned recommendations, the Super Bass Marshall heads take to effects pedals very well. There are many greats who have used the 100W Super Bass or its 50W variant (the Model 1986). Gary Moore's favorite and most used head was a 72' 100W Super Bass (nuff said).

Check out these two videos by a MF member that used to frequent this forum (don't know if he's here anymore or not)...

 

[pleximaster]

I would recommend keeping it stock, no mod at all, as it would hold its value, get a good attenuator to bring volumes down.

If you don´t like it with an attenuator you are better off to sell it, buy another similar already modded one (you´ll save money for not having to do the mod) and you will have cash in your pocket for something else.

Best regards plexi

 

[neikeel]

If it is that original after 44 years I suggest you keep it that way. I modded my son's 71 Superbass but it was a car crash when I got it. I actually restored the main board virtually stock but added an extra preamp tube (in the empty, blanked off socket) and used the existing holes in the chassis to mount an extra board where the trem board would go, this was wired up split cathode with 2k7/0.68uF and 8k2 cathodes and 120k plate resistors, shielded wires to a 1M pot in the unused channel II high input wired it as a cascaded 2203. Experimented but ended with 1,800pF bypass on the 470k peaker. Input to that channel is Channel II low input.
I used the channel II volume pot as pre-PI MV (like usual Marshall MV).
Only mod to channel I was 1k5/22uF cathode and 100pF on the volume pot.
So now you plug into channel 1 you get a nice crisp SB (he mainly plays bass) using winged C 6550s.
Plug into channel 2 you get lovely 2203 tones (slightly hot-rodded but still true to tone type) and you can AB-Y between the two. Of course I could have gone further with footswitches and effects loops (the Metro/SDM is excellent and fits in the spacing of the spare US 4-output amps (you do not need it switched and drill the hole in the back panel for the microswitch- it is that transparent).
I did not drill this SB chassis/panel as it is a UK one.
So it is possible if you want (I used stock Marshall type parts (Iskras and Pihers and Lemco doggones) and it is all reversible.

 

[jack daniels]

Some things are reversible.

 

[ampmadscientist]

So I have, I believe, a stock '72 100w Superbass. Long story short, an ebay find around 10 yrs ago that went into storage before I took off for a couple tours in Iraq. I just dropped it off at a reputable tech but am looking for any recommendations on what should be done. It looked original inside (clean) with an old nasty non-grounded power cord attached. Guessing its completely stock, but not sure.

I'm mostly interested in fairly cleanish plexi tone, big warm punchy tube sound & will drive/boost it with od pedals. Want to avoid any ice-picky gnarliness. Will be using a maple neck 80's Strat w/ single coils (SD SSL-1s).

Any recommended minor mods I should be aware of? Guidance from the experienced would be greatly appreciated.

thx!

PPIMV won't do a lot of good until you modify the preamp for more gain. The thing to do with this amp is change preamp to 2204.
Putting PPIMV in this stock amp is a disappointment, it's not going to do what you expect.
But if you do install PPIMV, the trainwreck design is better sounding.

Amp is really clean until it is cranked wide open, then it works with an attenuator best. Wide open is really where this amp starts to work like you would expect.
Otherwise it just sounds like a Fender amp if you keep the volume turned down.

OD pedal is second best or third best, you won't get the Marshall tone from a pedal.

What most people don't realize is that this era of amp is a very clean amp.
Volume 7-10 / high gain preamp tubes is the only way to make it sound like anything.
But then if you do play it wide open, it's got a really great sound all by itself. (yes really)

Collectable
if it's never been touched, of course it's worth more as a collectable.
It depends on if you intend to play it, or collect it. That's 2 opposite sides for sure.

Modifications
If modified, anything should be fully reversible.
The amp should not be damaged, or gooped with glue on the circuit board.
No holes drilled in the chassis please.
All of these hacks are unnecessary and pretty pointless. It just wrecks a perfectly good amplifier.
It could be modded without making a big slop mess, hacks which are essentially unprofessional.
Overall, Marshall users should frown on these hack practices.

If the tech who mods it put glue all over the inside, drills holes all over it, they have lost my respect.
You could make it sound better, without trashing it.

 

[neikeel]

I don't think AMS actually read my post as he seemed to repeat nearly all of it

 

[mickeydg5]

Any modifications would depend on what the owner may want.

But if thinking you can get what is wanted out of it in stock form then start from there.

 

[Kladen]

Keep it stock.
Buy some good tubes.
Get it serviced.
Buy a good attenuator.
Rock on

I have my 76' super lead running on only two output tubes an a slight mod to lower the voltage on the output tubes a bit.
Nos preamp tubes and groovetubes output tubes. New caps because the old ones were bad. Other than that we changed a few components to original specs as marshall in 76' May have had a shortage on proper components.

Now my baby just sounds killer without any holes drilled

 

[GIBSON67]

Get some vintage Mullards for your V1 - V3. Bias the power tubes and crank that fuxker to your hearts content! And most of all...HAVE FUN and ENJOY!

 

[jack daniels]

Even though I proposed mods that can be reversed per the OP's request, my advice would follow the purist approach by NOT modding ALTHOUGH don't use an attenuator either unless you're ready to pay a premier transformer winder's rates for rewinding your stock OT.

 

[thegaindeli]

For the love of all that is righteous and true... DO NOT modify that amp! If you want a MV amp, buy a Marshall kit build. The right combination of pedals with a '72 Super Bass 100 may be the best Marshall tone I've personally ever heard. I've owned several stock '72 SB amps, and there's not a day that goes by that I don't regret selling them.

 

[Kris Ford]

Haven't peaked under the hood of my '74 Super Bass, but it has the one wire mod for sure, and I get a rougher, gainier, chewier and just plain DIRTIER grind than I do from my '78 2203 when BOOSTED...
So the one wire mod is minimally invasive, and brings tons of gain to lower volumes..
Though I'm not sure what else is going on yet, but it's running GT 12AX7Rs which are just rebranded Sovteks, which seem to work best, I tried rolling in some JJs, and they were TOO much..
But NO extra holes, and was done before I got it.

 

[spinal]

I have a 69 or 70 Super Bass head.

I did both Larmar master and metroamp FX loop.
-> The Larmar volume is great to make the head more usable, but don't expect to achieve "bedroom" volume or even play small gig with it.
It is just great to tame the volume a bit but it will still be a loud amp. I never set the master at less than 6 then I feel like the tone is being afected.
-> effect loop, forget it, on this circuit it is not working well because usually you want an FX loop for crunch tones not clean tones.
But on Super Bass when you the head is crunching, the power section has already reached saturation which means that the FX loop will crunch too.

 

[yladrd61]

Grounded power cord, Electrolytic Caps Pre PI MV... keep the Super Bass Pre Amp Circuit sounds great with a Single Coil Strat....

 

[JeffH]

Thank you for your service and welcome (home)!

I guess I'm a purist, but I would leave it stock other than routine maintenance. There's a reason it's a classic.