Hoffman Amplifiers
> Tube Amp Building - Tweaks - Repairs
> new amp!
<< Prev Topic | Next Topic >>
Author Comment
idiotequed
Hey get your own solder
Posts: 224
(3/16/04 1:59 am)
new amp!
--------------------------------------------------------------------------------
one of the guitarists i tech for just bought an orange ad30 combo, so he wanted to sell his old amp...that means i walked away with a 1965-66 (i'll have to check numbers to see for sure) blackface bassman with match cabinet. the amp looks beautiful, it's in great condition. i'm going to swap the board out with a turret of the same circuit in the near future to lower the noise levels and all that. i'll get some pics in the near future!
HStraub
Senior tube assistant
Posts: 222
(3/16/04 7:47 am)
Re: new amp!
--------------------------------------------------------------------------------
Great amp, great catch..........but......why swap out the board? If it is in great shape, those are classics and worth some $$$ why not keep it stock and tinker with it to quiet it down? And keep your investment growing.....
ganzonimx
Hey get your own solder
Posts: 432
(3/16/04 11:29 am)
Re: new amp!
--------------------------------------------------------------------------------
I second Harry's statement.
Converting to a bus ground is not difficult in these amps, I separated in my BF Bassman the grounds of the filter caps and lifted the 100 ohm resistor from the PI tail the the preamp ground and connected it to the PT bolt ground. After that the amp was really quiet.
Cris
Funkalicousgroove
Junior tube assistant
Posts: 24
(3/16/04 5:57 pm)
Re: new amp!
--------------------------------------------------------------------------------
Please don't gut a classic!!! I'll Buy it from you if you don't like it the way it is
idiotequed
Hey get your own solder
Posts: 225
(3/16/04 9:40 pm)
re:
--------------------------------------------------------------------------------
goodness, the feedback! let me explain myself:
the former owner of the amp was having some decently severe issues with the noise floor of the amp when recording; it's pretty noisy and i've had to open it up more than once to try to get this mysterious crackling taken care of. the old board is horribly warped and all the caps are pushing 40 years, so i thought that i'd just swap the board cleanly; i wasn't even planning to change the circuit.
now i haven't had a whole lot of playing time on the amp so maybe i won't do a thing to it after i get used to it. but i reiterate that the main reason the amp was even sold was because it was too noisy!
6G6
Junior tube assistant
Posts: 128
(3/16/04 9:58 pm)
Re: re:
--------------------------------------------------------------------------------
I'd start with a complete recap.
It's not like it isn't due by now.
HotBluePlates
I only work on Fender's
Posts: 706
(3/17/04 6:53 pm)
Bassman Problems
--------------------------------------------------------------------------------
The warped board is probably normal. I've never seen an old Fender with a board that wasn't curved or warped (and I've owned TONS of them).
The crackling noises are most likely due to the 100k plate resistors getting old and noisy. Especially if the crackling comes and goes.
Other possibilitiesinclude arcing switch contacts, dirty pots or tube sockets contacts, etc.
Drilling holes in old amps always seems to reduce the value, and blackface amps are getting rediculously expensive (and I thought I had paid a lot when I bought a BF Princeton Reverb for $450 and a BF Super Reverb for $800. They're selling for double that now).
idiotequed
Hey get your own solder
Posts: 226
(3/17/04 9:22 pm)
re:
--------------------------------------------------------------------------------
so how much would a fender bassman (1966 i think) with matching cabinet fetch?
if i do ever end up making a turret board for the old amp, i was going to use the existing holes in the chassis, not drill new ones.
as for the crackling, it would happen randomly due to vibration when playing; if you hit the top of the amp with your fist, it would be really loud, as though something was shorting to ground. after we put some paper below the board it seemed to help a little, but at the very least i'm going to have to remove the board and clean house, install new caps, and try to find any perticular component making the crackling.
<< Prev Topic | Next Topic >>
Topic Commands
Click to receive email notification of replies
jump to: Tube Amp Building - Tweaks - Repairs (New)New Product Suggestions (New)Praises - Complaints - Suggestions (New)Buy - Sell- Trade (New)Archives (New)
- Hoffman Amplifiers - Tube Amp Building - Tweaks - Repairs - Hoffman Amplifiers -
Powered By ezboard® Ver. 7.32
Copyright ©1999-2005 ezboard, Inc.
Topic: new amp! (Read 3064 times)