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Vintage threads from the first ten years

modifying a champ for direct recording

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6/7/1998 12:13 PM
Claude Morrow	modifying a champ for direct recording I own a Fender Champ and would like to add a direct recording output, how would I do this and is it very difficult for a novice? Thanks

6/8/1998 7:32 AM

Hi Claude,

This procedure is detailed in Gerald Weber's first book, and is really easy.. I believe it consists of two resistors, which form a voltage divider, and I'd put it in some kind of metal box to sheild it.. I built one and had good results, but I used mine to drive a large SS power amp. It should work well for direct recording. I'm at work right now but will try to get the directions emailed to you tonight.

regards,

Steve

6/8/1998 9:00 AM
Benjamin Fargen	You might try to copy the design that the matchless spitfire uses for it's direct line out. I don't know if it would work or if this is the sound you are looking for. It's worth a look. Good Luck. Benjamin.

6/21/1998 10:36 PM
mike thompson	look at my book published by Bold Strummer Books "Great Tube Amp and Guitar Mods". It answers your question in detail.

6/8/1998 6:56 PM
Steve A.	Claude: You will probably want to equalize or process the signal from a simple two-resistor line output jack since the speaker itself filters out some of the high-freq garbage and shapes the sound. For best results recording most people end up miking the speaker. Steve Ahola

6/8/1998 9:38 PM

Claude,

I checked Weber's book, and the line out was for a tweed deluxe, which should work okay but you'll have to put this in parallel with the existing speaker so the output transformer has the correct load.

Basically solder a 100 ohm resistor (1/2 watt) across both the + & - terminals, then solder a 2.2K ohm resistor in series with the + terminal and a bare wire in series with the - terminal.

Steve A. is right, this will probably not sound as good as a miked speaker, but YMMV.

regards,

Steve M.

6/9/1998 3:57 PM

Probably good to ask just *where* you want to record from, and what it is you want to capture, since that determines the nature of the output.

Do you simply want to use the pre-amp stage from the Champ, or the power amp stage?

There was a post-output direct-out mod in GP many years back that is similar to the Weber one described in Steve's post, although I seem to recall a high voltage capacitor in series. I'm pressed for time right now, but when I have a chance I'll dig up the article.

While I've got you, please note that in many Champs, you can pop out the 6V6 tubes and replace them with 6L6 tubes, though you can NOT do the reverse substitute (not unless you like watching tubes go poof for fun). The 6L6's distort a little differently, and tend to have a little more bite in the class A configuration used in many earlier 3-tube Champs. If you can correctly identify the negative feedback resistor from the output transformer, you can also try lifting that to get even more bite. I did the mod to my 59 Princeton....ouch, that's some serious treble.

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