#1
I currently have the Fender Vibro Champ XD which has great tone and is all I need for me, but it just is a few decibels short of being perfect at gigs (like gymnasium sized rooms). My First idea and principal one is to make it into a cab and a head, and make the cab loaded with 2 10" speakers, but I realize it would barely add any volume (right?)

It is (currently) a 5 watt amp, with a 6V6 power tube and a 12AX7 pre-amp tube. It says that the speaker needs a 4Ω minimum rating, So I assume I can use an amp with 8Ω, or more?
Financially, I can't just go buy another amp for gigs, but I could save up for a speaker or two and get birch plywood to make the casings for the cab and head.
Heres a google pic of it:


TL;DR What summer project can I do with my combo to make it pump out more sound?
Just call me Julius, J, etc.
Taking an Internet break for a while, will come on when I can.
#2
A better set of tubes like JJ/Tesla will give u a little more volume. a better(more efficient) 12 inch speaker or two would help. Dont get more 10 inch speakers.

A better output transformer would give u more volume too.

I run my Epi valve jr and VHT Special 6 through my home built 2X12 cab, there 5 and 6 watts.

There are plenty of mods for fender champs out there, u just have to search for them
More than likley the champ has a low input and that can be changed to a high input by a simple resistor swap
Last edited by mcamp1230 at Mar 31, 2011,
#4
The only problem with trying to add more volume to a tube amp, is you're limited by the output power of the tubes. If the tubes are already producing full power, no mod will allow you to get more power - it's simply not possible. Your best bet is to install higher efficiency speakers.
#5
Quote by adambauman31
can you mic it through a PA system? if so, that'd be the easiest and cheapest

This. Gigs that size should always have the guitar amps miced up.
#6
Quote by mcamp1230
A better set of tubes like JJ/Tesla will give u a little more volume. a better(more efficient) 12 inch speaker or two would help. Dont get more 10 inch speakers.

A better output transformer would give u more volume too.

I run my Epi valve jr and VHT Special 6 through my home built 2X12 cab, there 5 and 6 watts.

There are plenty of mods for fender champs out there, u just have to search for them
More than likley the champ has a low input and that can be changed to a high input by a simple resistor swap

I thought that going from 8" to 12" would help, but I just wasn't sure. I'll look into the mods, there might be something that could help. I still want to build a cab though.

Quote by KG6_Steven
The only problem with trying to add more volume to a tube amp, is you're limited by the output power of the tubes. If the tubes are already producing full power, no mod will allow you to get more power - it's simply not possible. Your best bet is to install higher efficiency speakers.

If I swapped tubes, then could I mod the output transistor (is that the proper term?)

Quote by adambauman31
can you mic it through a PA system? if so, that'd be the easiest and cheapest

No I can't at my school, there just isnt one (most of my outdoor playing is at school things)
Just call me Julius, J, etc.
Taking an Internet break for a while, will come on when I can.
#7
Nope, output transformer

Just make sure you get good speakers or you may not get much of a volume boost, not like it will be a huge difference anyway, but very worth it...
#8
Quote by mcamp1230
Nope, output transformer

Just make sure you get good speakers or you may not get much of a volume boost, not like it will be a huge difference anyway, but very worth it...

I have no clue when it comes to speakers....I guess I'll just youtube the crap out of any one I find.
Just call me Julius, J, etc.
Taking an Internet break for a while, will come on when I can.
#9
I'm debating now between an Eminence Swamp Thang, or the Celestrion Greenback or Vintage 30's.
Just call me Julius, J, etc.
Taking an Internet break for a while, will come on when I can.
#10
those are all good speakers...vintage 30 probablly the loudest.
look at the speaker decible rating, i beleive that vintage 30's are 100 decibles

http://www.colomar.com/Shavano/2x12wiring.html, check this out youll need to know what ohm speakers to order and this shows different wiring options for 2X12 cabs. Only worry about the top 2 diagrams, and dont worry about any of the outs on the diagrams either...
Last edited by mcamp1230 at Mar 31, 2011,
#11
your champ haas a 4 ohm speaker output so you would want 2 8 ohm speakers wired in parallel to get a 4 ohm load.
Last edited by mcamp1230 at Mar 31, 2011,
#12
Speaker's efficiency is rated by how many db (decibels) the speaker will put out with 1 watt input, measured at 1 meter.

So a speaker that is rated 103 db 1w1m is better (more efficient....louder) than one rated 95 db 1w1m.
Loudness doubles every 3db

Go to a place on line that sells speakers and you will see this rating.
Parts Express is a good place to window shop
Last edited by Greg_M at Mar 31, 2011,