Fender Champ and Volume

Derrick Mau · From: Honolulu, Hawaii, USA

I have a 70's tube Fender Champ (silver face), original speaker.

The volume is pretty low compared to my other amps of the same size even when cranked to 10.

What could be the problem?

I changed two of the tubes except for the 5Y3 rectifier which was out of stock here.

Larry Clark · From: Herndon, VA.

I don't know what other amps you own that you are comparing it to but a 70's silverface champ is rated at 6 watts. Not a lot when compared to some of the little "powerhouses" that are available today.

Brad Sarno · From: St. Louis, MO USA

Yea Derrick, that little amp is a wonderful tone machine, but at 5 watts max, they're pretty quiet. They make for great studio or practice amps and also do well when playing with acoustic instruments. There are lots of other amps that size that will be 20 or more watts, so don't let the the size fool you. 5 watts is 5 watts.

Brad

Ken Fox · From: Nashville GA USA

I have yet to find a bad rectifier tube. If the amp is working,t he rectifier is likely OK. I have a ton of 5Y3 rectifiers, if you really want one!

The amp may have a bad bypass cap(s) on the preamp tubes, an open one will cause low volume. There are a host of other things that could be a problem or maybe not a problem at all, considering the low wattage of the amp.

Joseph Meditz · From: Sierra Vista, AZ

FWIW, I second what Ken Fox said. I think a likely suspect is the bypass capacitor on the cathode of the 6V6. The heat in that area can cause it to fail, especially the heat from the bias resistor.

Get a chopstick and gently tap or push the bypass caps and resistors and listen for any noises which indicates a loose or bad component.

If you suspect an open bypass cap, you can temporarily put another one in parallel with it without solder to see if that helps.

Joe

Ken Fox · From: Nashville GA USA

Good point, I forgot it was a cathode biased 6V6! The cathode bypass caps on the preamp tube can be problem as well.

Dave Mudgett · From: Central Pennsylvania and Gallatin, Tennessee

I dunno - my 68 Vibrochamp is pretty loud for a little 5-6 watt amp. But I put the original speaker in storage and use a somewhat more efficient, upgraded 4-Ohm 8" speaker. Perhaps it's bypass caps and resisors as mentioned, or perhaps even the power supply capacitors. But before that, I would suspect the speaker. Is the speaker 4 Ohms like the original, or has it been replaced with an 8 Ohm speaker. That makes a large difference - a Champ with the stock output transformer works best with a 4 Ohm speaker. I agree on the 5Y3 rectifier - if it lights up and the amp makes sound, it's almost certainly OK.

Of course, everyone has a different idea of what is "loud", and there is no comparison to a Twin Reverb or even a Deluxe Reverb.

One final thing - in my experience, a guitar with a weak pickup sometimes sounds weaker through a BF/SF Champ than, let's say, a Tweed Champ or something comparable from that era like a Supro/Bronson/Oahu amp. The preamps on many of those earlier amps were crude and distorted like crazy, while the BF/SF designs were more refined and linear. The upshot is that if the input signal to the earlier amps is smaller, they're still loud but distort less, while the BF/SF versions get quieter. Leastways, that's something I have noticed.

Jim Sliff · From: Lawndale California, USA

Derrick - what do you mean when you say "compared to my amps of the same size"? What amps? "Size" and "volume" are unrelated. It could be there's no problem at all, and you're comparing apples and pizza.

But one piece of advice - tak the speaker out of that amp, store it carefully in case you sell the amp, and put an inexpensive Weber Signature series 4-ohm ceramic magnet speaker in it. Those amps (I have 5) love those particular speakers, and your volume will jump noticably. Stock 70's Champ speakers are, as a rule, horribly inefficient and strangled sounding. It's also overdue for a cap job if it hasn't had one - and that should be mandatory if you're going to play it, before you blow up some rather expensive parts.

However - as I first said, let's define your comparison before gong too far in volume analysis.

Derrick Mau · From: Honolulu, Hawaii, USA

Hi Jim,

I was comparing the Fender Champ to my Fender Sidekick 20, Peavey Transtube 258EFX, and my Roland Microcube 30 which is respectfully at 20, 25, & 30 watts.

Though all close in size, I guess it was unfair to compare these to a 6 watt amp so,
I connected my steel this morning to my new Vox DA-5 which has an adjustable 1.5 to 5 watt setting. At the 5 watt setting, the Vox was still louder than my Champ. I then hooked up to my 2 watt portable Roland Microcube and the volume levels was very close even though the Champ is 4 watts more.

The 5Y3 tube in the rear lights up and looks okay. No problems that I can hear of with the tone, in fact, there's no breakup even at volume level 10.

I got this Silver faced Champ from someone of of E-bay so I think it may be a good idea like you all said to have a complete cap job done since I don't know when the last time the amp was ever used or serviced.

I'll certainly look into getting a Weber replacement too.

David Doggett · Posted 28 Mar 2006 9:45 pm

Derrick, I just got a Vox DA5. I think it is very conservatively rated. It is very loud for a 5 watt amp. It sounds to me like your Champ is doing about what it is supposed to do. Maybe a better speaker and new caps would boost it a little.

Jim Sliff · From: Lawndale California, USA

i agree. You're comparing apples and...artichhokes. Not only wattage, but totally different types of amps.

My guess is your Champ is fine volume wise...but I'd STILL replace the speaker and absolutely the filter caps!

Derrick Mau · From: Honolulu, Hawaii, USA

Thanks everyone for your input. Surely appreciated.

What happens if this original 4 ohms speaker is replaced with an 8 ohms speaker?
Do you risk damaging anything?

Also, do you need to adjust the bias on the new tubes, or does this amp have a fixed bias?

Jim Sliff · From: Lawndale California, USA

"fixed bias" means it's adjustable. Totally reverse-wording. But your amp is cathode-biased, which means you don't normally need to adjust it.

An 8 ohm speaker will sound really bad, lose a bit of power, and subject the amp to something called "flyback", which can damage the output stage. Most BF/SF Fender amps can take a 100% mismatch safely...not a Champ.

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