Welcome To the Hoffman Amplifiers Forum

September 07, 2025, 05:26:29 am
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Next on the list with my build..  (Read 2386 times)

0 Members and 1 Guest are viewing this topic.

Offline hesamadman

  • Level 3
  • ***
  • Posts: 732
Hoffman Amps Forum image
Next on the list with my build..
« on: August 20, 2013, 06:29:54 pm »
Well. Ive built my first amp. One thing id like to do with it is clean up a bit of the wiring. Since I technically built this twice, I learned a lot from the first to the second time. Things that I should have done different and things that I did in the wrong order.

I would really like to make some changes to this circuit. I am going to add a switch to change different value cathode bypass caps and see what that does. Id also be interested in adding a gain stage perhaps? The only reason I say this (not because I have any evidence of this being a good mod) but Ive heard that the Naylor Super Drive 60 is similar to the 800 with an added gain stage. I really like the tone Nick Perri gets with his.

What do you guys think? Waste of time? ANy other suggestions?

Offline John

  • Level 3
  • ***
  • Posts: 1895
Hoffman Amps Forum image
Re: Next on the list with my build..
« Reply #1 on: August 20, 2013, 07:17:54 pm »
Quote
I am going to add a switch to change different value cathode bypass caps

Before doing that, clip in the different values you think you'd like to see the difference. That way, after installing the switch you'll know what values of cap to choose between. Save you some soldering. If you think you'll keep messing with this hobby/addiction, decade boxes are a wonderful tool to have for both caps and resistors. I pick them up when they're cheap, and if I have to install new caps or Rs, so what? The box and rotary switch is worth the $20 IMO.

Glad you like the amp, and congrats on a nice first/second build! Each time I do one I see something I should have done differently. :smiley:
Tapping into the inner tube.

Offline hesamadman

  • Level 3
  • ***
  • Posts: 732
Hoffman Amps Forum image
Re: Next on the list with my build..
« Reply #2 on: August 20, 2013, 07:30:18 pm »
Quote
I am going to add a switch to change different value cathode bypass caps

Before doing that, clip in the different values you think you'd like to see the difference. That way, after installing the switch you'll know what values of cap to choose between. Save you some soldering. If you think you'll keep messing with this hobby/addiction, decade boxes are a wonderful tool to have for both caps and resistors. I pick them up when they're cheap, and if I have to install new caps or Rs, so what? The box and rotary switch is worth the $20 IMO.

Glad you like the amp, and congrats on a nice first/second build! Each time I do one I see something I should have done differently. :smiley:

Thanks for the info John. Would you mind explaing what decade boxes are and what they do?

Offline SILVERGUN

  • Level 4
  • *****
  • Posts: 3507
Hoffman Amps Forum image
Re: Next on the list with my build..
« Reply #3 on: August 20, 2013, 07:44:17 pm »
I was typing while john was responding,,,so I'll just leave it

Well Hamm,,,I can relate....
There are a ton of mods that you can do to this circuit.....it's a great platform for experimentation
You have come to the right place.....
You will get a lot of different responses when it comes to this question......some guys say "whatta ya need more gain for?"  :icon_biggrin:
Some will say "all I would do is this".....and others won't get involved because you're the 1 millionth guy who has thought that he can improve upon this amp,,,,just after building your first amp  :wink: (me included  :icon_biggrin:)
And a couple others know all the best stuff and won't give it up for free  :undecided:

You can get more gain out of the pre-amp as-is, without adding another tube (another stage).....adding gain adds noise, so you'll have to be careful with your lead dress and component placement

You probably don't need a switch to try different bypass caps......we use tools called decade boxes that clip in place of your caps and allow you to try different values....for now we can just give you different values to try and clip in one at a time....once you get above a certain value you won't hear much difference between 2.2uf, 4.7uf, 10uf,,, and you won't really need to install a permanent switch,,,unless you want to have a bypass cap "boost" switch that will just add or subtract the cap of your choice

BE CAREFUL!!!!! guys get shocked and we don't want you to experience it,,,,so some guys will shy away just because they don't want to give you instructions on how to kill yourself..........being an electrician,,,I'm going to assume that you understand electrical safety

I'm listening to Nick Perry, but I have a feeling I know what you're looking for.....I recently modded a 4212 for a guy who is extremely happy with it now.....the trick is to not go too far
« Last Edit: August 20, 2013, 10:15:14 pm by SILVERGUN »

Offline SILVERGUN

  • Level 4
  • *****
  • Posts: 3507
Hoffman Amps Forum image
Re: Next on the list with my build..
« Reply #4 on: August 20, 2013, 08:07:38 pm »
Here's a very easy mod that will make a big difference.....it will also alter your low input sound, so be careful

Try that and tell us what you like and/or don't like.....others will come along and clean up my mess  :icon_biggrin: (or maybe actually agree with me),,,I wish I had more time for you, but that's it for now

Your tele is going to squeal even more with this in there,,,,so be careful with your preamp vol. when you first turn the amp back on

Offline John

  • Level 3
  • ***
  • Posts: 1895
Hoffman Amps Forum image
Re: Next on the list with my build..
« Reply #5 on: August 20, 2013, 08:10:26 pm »
Quote
I am going to add a switch to change different value cathode bypass caps

Before doing that, clip in the different values you think you'd like to see the difference. That way, after installing the switch you'll know what values of cap to choose between. Save you some soldering. If you think you'll keep messing with this hobby/addiction, decade boxes are a wonderful tool to have for both caps and resistors. I pick them up when they're cheap, and if I have to install new caps or Rs, so what? The box and rotary switch is worth the $20 IMO.

Glad you like the amp, and congrats on a nice first/second build! Each time I do one I see something I should have done differently. :smiley:

Thanks for the info John. Would you mind explaing what decade boxes are and what they do?

http://www.ebay.com/itm/181183223553?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

There's a sample. Shop a lot before you buy. There are ridiculous prices on some of 'em. Pretty easy to swap in different caps or resistors if you want. I buy old ones and fix em up because that's more fun to me than buying something new that already works.  :laugh:
Tapping into the inner tube.

 


Choose a link from the
Hoffman Amplifiers parts catalog
Mobile Device
Catalog Link
Yard Sale
Discontinued
Misc. Hardware
What's New Board Building
 Parts
Amp trim
Handles
Lamps
Diodes
Hoffman Turret
 Boards
Channel
Switching
Resistors Fender Eyelet
 Boards
Screws/Nuts
Washers
Jacks/Plugs
Connectors
Misc Eyelet
Boards
Tools
Capacitors Custom Boards
Tubes
Valves
Pots
Knobs
Fuses/Cords Chassis
Tube
Sockets
Switches Wire
Cable


Handy Links
Tube Amp Library
Tube Amp
Schematics library
Design a custom Eyelet or
Turret Board
DIY Layout Creator
File analyzer program
DIY Layout Creator
File library
Transformer Wiring
Diagrams
Hoffmanamps
Facebook page
Hoffman Amplifiers
Discount Program


password