Mods to a bassman 100 head?

[Cruz Azul]

Hey Guys,

Got a bassman 100 head coming soon and just wondering what sorta mods people have done to them before? Have been reading a little about them and a little confused to be honest!

[ROKY]

Why do you want to mod it ?

[Cruz Azul]

Why do you want to mod it ?

I don't necessarily have to as I dig its tone already but just thought i'd see what others had done....

Nick

[CthonicEwes]

Er, leave it stock, especially if you're using it as a bass amp. I have no idea how it sounds with guitar.

[CthonicEwes]

Those mods are for a Bassman head. This thread is about a Bassman 100 head. It's a different beast, as far as I know, although there may be similarities.

[Cruz Azul]

Yeh this is a bassman 100 head which I like but was wondering what the differences were between it and a silverface bassman? Hence modding it to those sorta specs etc?

[CthonicEwes]

Um, off the top of my head, the Bassman 100 has 4 6l6's, whereas the Bassman only had 2 6L6s. So, probably the transformers are different, too. The preamp sections might be similar. Others with more technical knowledge will no doubt chime in.

The thing is--from my point of view, there are many, many SF bassman (bassmen?) out there. They sound great for guitar, and there are well known mods for them to make them sound even better. But I'm not sure how many Bassman 100s are out there. Not that many, I think. And they really do sound great with bass. So, I figure, leave this one for the bassists to relish it's lovely deep sound. But of course it's your Bassman 100 and you're free to do anything you want with it. Are you using it for guitar or bass?

[Cruz Azul]

Cheers mate!

Yeh i'm gonna use it for guitar and hear what you're saying about keeping it stock etc...

Was just curious as to whether anyone had modded them..

[paulg]

I think it was a Bassman 135 that I had. It had an ultralinear output, which I disconnected. It was basically a Twin without Reverb or Trem. So unless your going to mod it up with a lot of gain and a master its a clean platform. I'd recommend getting a good distortion pedal (Fulltone OCD) and enjoy the easy life!

[saltydogg]

My amp guy modded my '67/68 Fender Bassman (50W) head to these specs:

Normal Channel: Typical Fender Bassman circuit. Mad Headroom.

Bass Channel: "Trainwreck-type" circuit with Master V on rear panel. Zero headroom.

Using an A/B switch I can toggle the channels if necessary.

Just a thought. Good luck.

[RedRock]

A couple of years ago, I removed all of the Bassman 100 circuitry
and rebuilt it as a Tone Master. They both have 2 pre amp tubes, 1 phase inverter
tube and 4 6L6s. I added a small .6 amp 6.3 volt auxilllary transformer as a
power supply for relay channel-switching power. It worked fine.
I removed the Bassman 100 face plate and installed a Twin Reverb reissiue
face plate. I drilled additional holes in the Bassman front to accommodate
the number of holes required for the Tone Master controls-clean channel
4: Vol. Treble, Middle and Bass, and Distortion channel 6: Gain, Treble, Middle
Bass and Volume, and an added Hi-Cut control.
The Bassman 100 chassis will fit into a Twin Reverb cabinet. That is how
I have mine set up. The stock Bassman transformers worked great.
I added a Vox AC30 cross-line tone control with a .0047 mfd cap and a 1 meg
control as a Hi-Cut on the distortion channel. It is switched in with a relay
so it is in the circuit only when the distortion channel is selected. This tames
the well-known brightness of the Tone Master dirt channel.

[GtrWiz]

My amp guy modded my '67/68 Fender Bassman (50W) head to these specs:

Normal Channel: Typical Fender Bassman circuit. Mad Headroom.

Bass Channel: "Trainwreck-type" circuit with Master V on rear panel. Zero headroom.

Using an A/B switch I can toggle the channels if necessary.

Just a thought. Good luck.

Any more info on the Trainwreck circuit? Or info on the guy that did the mod?

[ROKY]

I think it was a Bassman 135 that I had. It had an ultralinear output, which I disconnected. It was basically a Twin without Reverb or Trem. So unless your going to mod it up with a lot of gain and a master its a clean platform. I'd recommend getting a good distortion pedal (Fulltone OCD) and enjoy the easy life!

:agree
I'm in the market for a Bassman 135 in the near future, and I'm going
to leave it stock and use it as a clean platform .

I have other amps that do other things well and I think people should
leave these amps the way they are - there are gazillions of great pedals
to use at this stage in the game, ya know ?!?!

[RedRock]

Any more info on the Trainwreck circuit? Or info on the guy that did the mod?


You can find the Trainwreck circuit at Schematic Heaven
and Blue Guitar. It's fairly simple, but is sensitive to layout
and must be carefully tweaked. Any good tech can do it.