how to convert your Fender Champion 600 to a 5f1 Tweed Champ
In this video we’ll hack up the champion 600’s PCB and convert it to 5F1 Tweed Champ specs! After this mod, which involves removing a lot of parts, the amp sounds so much better! Makes you wonder why Fender doesn’t let you have this amp in that configuration without buying your expensive ticket into the boutique club.
Reissue?
The Champion 600 (reissue) was a reasonably priced, read low budget amp. Looks like the one from the 40’s but technically it houses a blackface or silverface champ circuitry, but with inferior components. However, it’s design allows it to perform like a Tweed style amplifier with fairly simple work on the circuitry
A small practise amp that has the overdrive , harmonic richness and dynamics of the amp it was supposed to reissue was all we wanted anyway, so let’s go.
warning! working on electrical gear involves high voltages! make sure you are qualified and experienced in doing this kind of work. if not, leave it to someone who is! I'm not, i'm just desperate.
neccesities overview
Obviously we need a soldering iron. But we also need a bit of jumperwire a pair of plyers and a multimeter. It’s wise to have a drain cable or another safe way to drain the filter capacitors.
Component wise we only need: 22k@2W, 22k@1w, 1,5k@1w and a 0,022uF Tone cap. Optional some 2w resistor values ranging from 470 ohm to 1k to finetune the bias if needed.
modification steps overview
– Removal of R18, R19, R20, R21, R22.
– Removal of C1, C8 and C9
– Connect bottom of C1 to bottom of R21 with HQ Tone Capacitor. (Mallory or Orange Drop etc.)
– Jumper the connections over R3, R14, R17, R25 and R26
– Replace R7 with 22k@1W
– Remove C10. And C3 for less preamp gain. Before 5F1 the first cathode didn’t have this cap.1
– Replace R12 with the 22K@2W resistor, used the removed resistor in R11
– Replace R23 with the 1,5K resistor
– Calculate the output tube bias. Check the video how to. This amp can have the output tube running at 100%. However, due to the SS rectifier and net voltage from the wall it may even exceed the rating. When you want to use your nice NOS vintage tubes, beware of a too hot bias value. Cooling the amp down a tad will be better.
conclusion
So. The sounds that The Fender Champion 600 amp can deliver in this configuration, even with it’s PCB design and otherwise stock components is good. It makes you wonder why no low-budget tweed version wasn’t available in the first place. Especially when we see we mainly need to cut parts out and simplify the thing. I do would like to state that the stock amp sounds good on it’s own and I might do a proper A-B comparison between both. Therefore keeping a stock one is also an idea, or make the tone stack mod switchable. But, I do imagine most recording and touring guitarists would go for the more desirable tone, harmonics and responsiveness of a tweed amp, no?
Questions or amp-modding requests? Leave a comment or contact me here!
Regards, A
Well just for reference what specific type of music do you like to play and what kind of tone are you looking for (raunchy, sweet blues, twangy cleans?)? I have played Champion 600 s and I wasn t too impressed. Right now, Guitar Center has the Fender Ramparte amp on sale for about $210 after their big sale. It s a 9 watt tube amp with two channels, one thats meant for cleaner tame tones, and a hotter channel for a little crunch. It has a 12 speaker and can get pretty loud but personally I like the larger speakers for clean tone, and I practice in my bedroom with a 3 watt danelectro tube amp from the 50 s with a 8 inch speaker, and a 12 watt Fender Excelsior with a very loud 15 , and both are great for their own respective things. Look up the demos on the Ramparte, they re a big upgrade in quality and features in my opinion compared to the champ 600. Edited: Changes in content
Hi man,
I like a lot of different music styles, but when it comes to nasty rock and roll sounds small fender combo’s are the works for me. The Champion 600 is a super low budget amp, yet with the work as mentioned in the video and a speaker upgrade, you can make it sound like a Tweed 5F1 at a fraction of the cost. Micing up the small speaker can give big sounds. The 3w Danelectro will probably share a lot of the circuit with tweed fenders. Gr,
I just wanted to take a minute to thank you. Just did this mod on my Champion 600. Have had the amp for a few years, replaced the grill cloth to get rid of the “wet blanket” effect of the old cloth. Kept the stock speaker (gets better with break-in). Never was too excited about the tone, though. That is, until I ordered the parts I didn’t have, got the soldering iron out, and implemented your changes. It gave the amp what it was missing. Does it sound like a vintage champ. Not exactly, but it is close enough, and has a whole new personality. BTW, the video is perfect. Great work. Thanks again!
Cheers! Thanks for the kind comment and glad that it worked out! Regards, and Rock and Roll
Aldo would you show us a bias pot mod? Too include the band type and size of pot.
Ciao Ron,
Thanks for the message! Here’s the thing though, the Champ is a cathode biassed amp, so it biasses itself trough the signal from playing. Making an adjustable bias system probably won’t work well in such an amp. A single ended (single tubed) class A amp just runs at an about 100% of the tube’s capacity at all times. When too much over limit, you could cool that down a hair with a different fixed value bias resistor, or a rectifier tube that compensates for the modern outlet voltage. The one in the video has a SS rectifier so that’s not an option. The princeton reverb is already different story, where the fixed bias with the modern voltage values changes the amps overdrive charactistics, so an adjustable one is needed. Hopefully this is workable info. Kind Regards,
Aldo, Thanks. Ron
What does changing the OT to an 8 on and 12″ speaker do to the dynamics of this amp?
Ciao Ron,
Late reply but here it goes. It’s a good plan I think! The dynamics of the amp itself isn’t affected I think. It only increases flexibility and 5w will work ok on a 12 inch as long as the speaker is a low wattage one. 1×12 greenback (marshall voice), jensen p12r (fender tweed voice) or something will be fantastic. Recently I hooked up a 8 Ohm loadbox to make it a kind of plexi and using speaker IR’s. Sounded cool! Check it out if you like:
Ideal situation would be to keep the tiny C600 box and having a speaker output jack to place it at a larger speaker cabinet when needed. And also have a 1×10 or 1×12 cabinet where the amp fits in as well to be able to bring it as a larger single combo.
Cheers!
How important are the materials of the resistors (carbon film vs metal oxide )
And is there another name or part number to look up for the tone cap I can’t seem to find it
In all honesty the material doesn’t matter that much. The wattage does. Legend has it that carbon resistors have mojo as they tend to drift out of value which cause ‘issues’ that can sound musical as well. Tonecap just look for a 0.022uF (Microfarad) valued audio cap and good to go. Regards,