Vibro-Champ Help

[Rick1114]

I just purchased a 1966 BF Vibro-Champ off ebay for $400. It was advertised as working condition and original. I received it today and the power light does not turn on and generally there is no sound, but if I bring the volume up to 10, I can hear a little bit of sound but it's all distorted and the volume pot sounds all scratchy as well. I tried swapping tubes (except for the SY3, I didn't have on of those), but it's the same, no power light, barely any sound. I'm just hoping it's not the transformer, because that will affect the value too much. I've already e-mailed the seller requesting refund if there is a real problem here.

Any ideas?

Thanks,

Rick

[52 Bill]

I think that the two problems are related only in the fact that they both could have been caused by rough handling in shipment.

the power light does not turn on

Remove the red lens and try wiggling the bulb to see if it is making contact in the socket. If that doesn't work, remove the bulb and check it with an ohm meter. If you get an ohm reading, then you'll have to check for the 6 vac filament voltage in the amp. Do the power and pre-amp tube filaments light up? If they do, then the 6 vac winding on the transformer is working, but not getting to the pilot lamp. Sometimes a dirty/oxidized socket connection will cause this.

there is no sound, but if I bring the volume up to 10, I can hear a little bit of sound but it's all distorted

Did you check the speaker and speaker wires?

You need to check and see if the rectifier is working or not. You also will need to check to see if anything came loose during shipping. Open up the amp and visually inspect for any broken solder joints, loose parts, wires, etc. Get a copy of the schematic and start by checking the power supply voltages.

[stokes]

"I can hear a little bit of sound but it's all distorted and the volume pot sounds all scratchy as well."
Check for DC voltage on the volume pot.

[Rick1114]

The light came on with a little wiggling. Amp still not working though - nothing till you hit 8 on the volume and it just a little distorted sound. I poked around with a chopstick and no dice. The connections seem solid for the most part. I'm starting to feel a little in over my head. I have a multi-meter and can startchecking voltages tomorrow. Never done it before though - where do i start?

[Rick1114]

52 Bill -

You were right on both counts! A connection went loose in the speaker that I didn't notice until I took it apart. Amp sounds great. The volume pots a bit scratchy, and it needs a good cleaning, but other than that it's a real nice amp. Looks to be 100% original, even came with RCA 6V6/SY3 and Mullard
12AX7's! Here's a pic of the inside:



Thanks for your help

Rick

[Jaybird]

You can now relate to how Edison must have felt when his telephone worked!! "Watson I need you!!." LOL Have fun with your new toy.

[Rob Mercure]

Rick,

Can't remember whether Fender sourced their 6V6s from RCA but the original 12AX7s would have been RCA sourced - 6L6s were usually RCA. While the amp looks nice inside it's also obvious that it's hasn't had a "cap job" - that is, replacing the electrolytic capacitors that eventually dry up (I remember somewhere getting the information that the factory service life of these parts was 15 years - but we've all seen 50 year old units that perform). I'm basing this on the white cathode bypass caps - there should be large aluminum can and if it doesn't have evidence of change (or a few large tubular capacitors added around it's base) then you're going to have to change this guy at some point. Just normal maintanence like changing tires on a car and until these parts are functioning optimally you won't get full performance from the VC.

These are fun little beasts and using an better/larger external speaker really opens up their sound. Oh, 'nother FYI, some of the speakers (can't remember which mfg. right now) are bad for having the foam surround disintegrate - if this happens look at it as an opportunity to put in a higher quality speaker.

Rob

[Rick1114]

Thanks for the info Rob....

Suprisingly this amp sounds great - it has that "broken in" sound, and the mojo is there 100% (my wife even loves it, if that tells you anything). I thought I would miss reverb, but not at all. The nice vibrato and the 3D soundstage sound better than a splash of reverb w/reissue amp . To perform optimally it will need some work for sure. It also has some stains on the cabinet/tolex that have to figure out how to remove (like it's been sitting in the garage for a looong while).

I'm not sure what to do with it yet - fix it up as a project amp or "keep it original".

[Jaybird]

The amp looks great. I have always had success cleaning my amps with 409 and a soft white cloth. As far as the reverb goes, if you were to try a Boss DD-3 pedal, the amp would blossom.

[52 Bill]

52 Bill -

You were right on both counts! A connection went loose in the speaker that I didn't notice until I took it apart.

Great to hear that it's working again. Sometimes it's just the simple things that get overlooked.

Great looking amp, it's a keeper!

[Rick1114]

What speaker do you guys like in this amp? I'm looking at Weber or jenson, not sure if anything else is offered. Something that will deliver more lows would be nice, but keep the same fender sound intact....

Any suggestions would be appreciated!

Thanks,

Rick

[Chuck H]

IIRC I don't think it's possible to remove the baffle on that cabinet. But I do know that a 10" speaker will fit if you cut the hole in the right place. Going up to a 10 will greatly improve your low end AND speaker choices. It's your call on whether or not to "damage" the amp by doing this though.

If you choose to stick with the 8" speaker there arent many choices. Jensen sells a "reissue" of the original. If it's anything like the other Jensen speakers it won't sound as good as an original. Other than that the Tone Tubby gets praise. Weber offers special options, but I don't know if that applies to the 8". The EH is a "budget alternative" by advertising descriptions. And thats all I know about it. So your choices would pretty much be a Tone Tubby or a Weber. I havent heard either.

Chuck

[Rick1114]

I ordered a Weber GA100. Seems like the best replacement available for my needs. 15W, described as warm and crunchy - Any opinions on these?

[Chuck H]

Did you mean the 8A100? Those get high marks. I haven't heard one. Described as "warm tone" and "early breakup" in more than one review. When it first came out it was considered THE go to speaker for Champ replacement.

[Rick1114]

Meant 8A100 that for the correction. Hopefully the real thing sounds like the description!

Rick