Jumpering Your Bassmen

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MrShake
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Jumpering Your Bassmen

Post by MrShake » Thu Mar 22, 2018 7:18 am

Hey everybody.

So, last November, my Bassman Ten crapped out. Started making a crackling sound and humming at band practice. Fortunately, it was two days AFTER our big show. Anyway, the amp sat in the rehearsal space for months, I finally went over to pick it up and bring it home to store until I can save up some cash to get it fixed. Thought it might be a blown tube or something (the sockets could be tighter, maybe one slipped?), but it hasn't been in the shop since '08, so it's probably overdue for a tune-up anyway.

In the interim I've been playing on my ADA-based rack setup. It's fantastic, and I've been having fun learning to play with that Marshall-y sound. But today, I plugged in the B10, made sure the tubes were well-socketed, and flipped it on. There was a noticeable hum and little volume, but after a while, the hum dissipated and everything sounds... pretty normal. So, victory for me -- I don't necessarily have to take my amp to go get fixed! Add an offset and a pedalboard and Rig #1 (punky garage-gaze) is back in business!

Anyway, it's been so long since I played it (and not really much in the months before it stopped working), that I'd almost forgotten to jumper the channels. Then it occurred to me that I have no real idea if there are different configurations of jumpering that might yield different results. Anyone have any suggestions, or is it just a matter of making sure to get some signal into each channel? I know some use a Y-cable...

Anyone have any personal configuration recommendations for jumpering the channels on a silverface Bassman, Ten or otherwise?

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oid
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Re: Jumpering Your Bassmen

Post by oid » Sat Mar 24, 2018 1:47 pm

No comments on the jumper question, possible answer to your previous issues.

The timing of your issues suggest a likely cause, November tends to be humid, the amp returned to normal after sitting through the dry winter heating season. The vulcanized fiberboard Fender used in their amps sometimes absorb moisture and become conductive enough to cause problems. Dust build up in the amp can do much the same in humid situations, the old Fender chassis is fairly good at keeping the dust out though. You just need to watch the amp, if the issue returns after a good humid spell there is a good chance something in the amp is doing a sponge imitation.

These boards are abit of a headache and either the affects of time are not so good to some of them or the quality control on the boards was not always the best, some do indeed seem barely vulcanized. The copious amounts of flux Fender tends to leaves on the boards probably does not help the situation either.
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46346
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Re: Jumpering Your Bassmen

Post by 46346 » Mon Apr 02, 2018 11:11 pm

re: jumpering, i don't do it a lot - i have really tubed and tweaked my normal channel to my liking. but when i do jumper, it tends to be:

• Guitar> Normal input 1
• Short jumper from Normal input 2>Bass input 1
• Normal volume adjusted first (with Bass volume down)
• Bass volume adjusted after Normal is set.

this is on my '61 and '66 Bassman heads. i did have a Bassman Ten but it was so long ago that i don't remember if i ever jumpered it.
pretty cool amp, though, kinda wish i kept it longer. problem was, i was actually playing bass!
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Re: Jumpering Your Bassmen

Post by s_mcsleazy » Wed Apr 04, 2018 12:29 pm

ive been guilty of jumpering my bassman on both guitar and bass. i dunno about your solution but it sounds pretty ok
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Re: Jumpering Your Bassmen

Post by MrShake » Sat Apr 07, 2018 6:41 am

oid wrote:
Sat Mar 24, 2018 1:47 pm
The vulcanized fiberboard Fender used in their amps sometimes absorb moisture and become conductive enough to cause problems.
That's great advice, I'd actually never heard that! I'll keep my eye on it during humidity swings to see if it's recurring.
46346 wrote:
Mon Apr 02, 2018 11:11 pm
...when i do jumper, it tends to be:

• Guitar> Normal input 1
• Short jumper from Normal input 2>Bass input 1
• Normal volume adjusted first (with Bass volume down)
• Bass volume adjusted after Normal is set.
Mmmmm... tasty! Thanks! I think even re-evaluating my perspective on how/when to adjust each volume, and experiment in a more detailed way with that has led to some well-balanced tweaking.
46346 wrote:
Mon Apr 02, 2018 11:11 pm
i did have a Bassman Ten but it was so long ago that i don't remember if i ever jumpered it.
pretty cool amp, though, kinda wish i kept it longer. problem was, i was actually playing bass!
It is. I knew it was no prize-winner when I bought it, but I knew it was big, clean, Fender, and super-solid Silverface construction. But I've really bonded with it. Playing other peoples' Twins and the like always seems so clangy and trebly when compared with my JM, flatwounds and B10. It's serviceable on bass for the couple of small gigs I've used it for, sounds great on guitar with a ton of clean headroom... and of all the amps I've played one through, it's my favorite Bass VI(-style) amp. Punchy 10"ers, closed back, dark oomph. Warm and tubey, but let the pedals do the talking. I'd never try to claim it's the best amp in the world, but it hits that sweet spot for me even over other "nicer" amps I've tried since.

s_mcsleazy wrote:
Wed Apr 04, 2018 12:29 pm
ive been guilty of jumpering my bassman on both guitar and bass. i dunno about your solution but it sounds pretty ok
What's your bass board looking like these days? I'd like to figure out some new ways to approach bass on this amp. And you're probably the best known Silverface Bassman bassman around these parts. Anything you use with it that sounds especially good?

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Re: Jumpering Your Bassmen

Post by s_mcsleazy » Sun Apr 08, 2018 6:44 am

my bass board nowadays is kinda scattered to the winds because right now, im not playing much bass. but at last look it was all the dirt pedals going to the bassman and jumpering the channels with a y cable so i could also send that signal into the pa head i use as a slave and the clean signal going into another channel on the pa head.
offset guitars resident bass player.
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Re: Jumpering Your Bassmen

Post by 46346 » Sun Apr 15, 2018 5:16 pm

yeah - i always thought the B10 might have been designed for the Bass VI. except that they started like 10 years apart. or maybe they took ten years to get around to doing it.
that's a great little situation there that combo!
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Re: Jumpering Your Bassmen

Post by Chip Korea » Fri May 18, 2018 11:46 am

Maybe a random place to ask, but I was thinking something because I read about building your own cabs and rust being caused by the wood drying out. Does anyone put bags of those little moisture absorbing pellets in their amps or cabs? Does it make sense as an idea if you know or fear moist air or timber?

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